No. 454 

Technical Report Series 

NATIONAL TOXICOLOGY PROGRAM 

(CAS NO. 10101-97-0) 

STUDIES OF NICKEL SULFATE HEXAHYDRATE 

TOXICOLOGY AND CARCINOGENESIS 

IN F344/N RATS AND B6C3F, MICE 

(INHALATION STUDIES) 

National Institutes of Eealth 

Public Health Service 

U.S. DEPARTMENT OF HEALTH AND HUMAN SERVICES 
FOREWORD 

applied research and to biological assay development and validation. 

relevant programs, staff, and resources from these Public Health Service agencies relating to basic and 

Carcinogenesis Bioassay Testing Program, NCI, was transferred to the NIEHS. The NTP coordinates the 

Institute for Occupational Safety and Health (NIOSH), Centers for Disease Control. In July 1981, the 

National Center for Toxicological Research (NCTR), Food and Drug Administration; and the National 

the National Institute of Environmental Health Sciences (MEHS), National Institutes of Health; the 

Health and Human Services (DHHS): the National Cancer Institute (NCI), National Institutes of Health; 

The National Toxicology Program (NTP) is made up of four charter agencies of the U.S. Department of 

primary prevention of disease. 

hazardous chemicals. This knowledge is used for protecting the health of the American people and for the 

The NTP develops, evaluates, and disseminates scientific information about potentially toxic and 

assurance audits before being presented for public review. 

Practice Regulations, and all aspects of the chronic studies were subjected to retrospective quality 

studies were conducted in compliance with Food and Drug Administration (FDA) Good Laboratory 

with the Public Health Service Policy on Humane Care and Use of Animals. The prechronic and chronic 

applicable federal, state, and local health and safety regulations. Animal care and use were in accordance 

conducted in compliance with NTP laboratory health and safety requirements and must meet or exceed all 

The studies described in this Technical Report were performed under the direction of the NIEHS and were 

studies. Selection per se is not an indicator of a chemical’s carcinogenic potential. 

other species and quantitative risk analyses for humans require wider analyses beyond the purview of these 

this Technical Report are based only on the results of these NTP studies. Extrapolation of these results to 

human exposure, level of production, and chemical structure. The interpretive conclusions presented in 

Chemicals selected for NTP toxicology and carcinogenesis studies are chosen primarily on the bases of 

carcinogenic activity, of selected chemicals in laboratory animals (usually two species, rats and mice). 

These studies are designed and conducted to characterize and evaluate the toxicologic potential, including 

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Management. The Abstracts and other study information for 2-year studies are also available at the NTP’s 

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TOXICOLOGY AND CARCINOGENESIS 

ON THE 

NTP TECHNICAL REPORT 

STUDIES OF NICKEL SULFATE HEXAHYDRATE 

(CAS NO. 10101-97-0) 

IN F344lN RATS AND B6C3Fl MICE 

(INHALATION STUDIES) 

July 1996 

NTP TR 454 

NIH Publication No. 96-3370 

National Institutes of Health 

IPublic Health Service 

U.S. DEPARTMENT OF HEALTH AND HUMAN SERVICES 
2 Nickel Sulfate Hexahydrate, NTP TR 454 

CONTRIBUTORS 

National Toxicology Program 

Evaluated and interpreted results and reported findings 

K.L. Witt, M.S., Oak Ridge Associated Universities 

D.B. Walters, Ph.D. 

G.S. Travlos, D.V.M. 

G.N. Rao, D.V.M., Ph.D. 

A. Radovsky, D.V.M., Ph.D. 

J.K. Haseman, Ph.D. 

J.R. Hailey, D.V.M. 

T.J. Goehl, Ph.D. 

M.R. Elwell, D.V.M., Ph.D. 

M.P. Dieter, Ph.D. 

R.E. Chapin, Ph.D. 

J.R. Bucher, Ph.D. 

D.A. Bridge, B.S. 

J.K. Dunnick, Ph.D., Study Scientist 

Experimental Pathology Laboratories, Inc. 

Provided pathology quality assurance 

E.T. Gaillard, D.V.M., Ph.D. 

S. Botts, D.V.M., Ph.D. 

J.F. Hardisty, D.V.M., Principal Investigator 

Dynamac Corporation 

S. Brecher, Ph.D., Principal Investigator 

Prepared quality assurance audits 

Research Institute 

Lovelace Inhalation Toxicology 

Conducted 16-day studies, evaluated pathology findings 

J.A. Pickrell, D.V.M., Ph.D. 

P.J. Haley, D.V.M. 

F.F. Hahn, D.V.M., Ph.D. 

R.L. Carpenter, Ph.D. 

D.G. Burt, D.V.M. 

J.M. Benson, Ph.D., Study Director 

C.H. Hobbs, D.V.M., Principal Investigator 

R.O. McClellan, D.V.M., Director 

Conducted 13-week studies, evaluated pathology findings 

G.M. Shopp, Jr., Ph.D. 

J.A. Pickrell, D.V.M., Ph.D. 

F.F. Hahn, D.V.M., Ph.D. 

Y.S. Cheng, Ph.D. 

D.G. Burt, D.V.M. 

D.E. Bice, Ph.D. 

J.M. Benson, Ph.D., Study Director 

C.H. Hobbs, D.V.M., Principal Investigator 

R.O. McClellan, D.V.M., Director 

Conducted 2-year studies, evaluated pathology Bndings 

K.J. Nikula, D.V.M., Ph.D. 

K.R. Maples, Ph.D, 

P.J. Haley, D.V.M., Ph.D. 

F.F. Hahn, D.V.M., Ph.D. 

G.L. Finch, Ph.D. 

Y.S. Cheng, Ph.D. 

D.G. Burt, D.V.M. 

E.B. Barr, M.S. 

J.M. Benson, Ph.D., Study Director 

C.H. Hobbs, D.V.M., Principal Investigator 
Nickel Sulfate Hexahydrate, NTP TR 454 3 

NTP Pathology Working Group 

(2 June 1994) 

Evaluated slides, prepared pathology report on rats 

J .R. Hailey , D .V .M. 

Experimental Pathology Laboratories, Inc. 

E.T. Gaillard, D.V.M., Ph.D. 

National Toxicology Program 

D. Dixon, D.V.M., Ph.D. 

NiPERA, Inc. 

J. Cullen, V.M.D., Ph.D., Observer 

Pathology Associates, Inc. 

M.P. Jokinen, D.V.M., Chair 

National Toxicology Program 

R.A. Herbert, D.V.M., Ph.D. 

National Toxicology Program 

National Toxicology Program 

A. Radovsky, D.V.M., Ph.D. 

Chemical Industry Institute of Toxicology 

K.T. Morgan, B.V.Sc., Ph.D. 

Analytical Sciences, Inc. 

Provided statistical analyses 

S. Rosenblum, M.S. 

N.G. Mintz, B.S. 

R.W. Morris, M.S., Principal Investigator 

(4 Month 1993) 

Evaluated slides, prepared pathology report on mice 

Experimental Pathology Laboratories, Inc. 

S. Botts, D.V.M., Ph.D. 

National Toxicology Program 

R.A. Herbert, D.V.M., Ph.D., Chair 

National Toxicology Program 

S.L. Eustis, D.V.M., Ph.D. 

National Toxicology Program 

D. Dixon, D.V.M., Ph.D. 

National Toxicology Program 

K. Takahashi, D.V.M., M.Sc., Ph.D. 

NiPERA, Inc. 

J. Swenberg, D.V.M., Ph.D., Observer 

National Toxicology Program 

J.R. Hailey, D.V.M. 

Chemical Industry Institute of Toxicology 

J. Everitt, D.V.M. 

Biotechnical Services, Inc. 

Prepared Technical Report 

S.M. Swift. B.S. 

T.A. King-Hunter, B.S. 

S.R. Gunnels, M.A. 

J.R. Carlton, B.A. 

C.M. Bailey, B.S. Pharrn. 

D .D . Lambright, Ph.D . , Principal Investigator 
4 

CONTENTS 

EXPLANATION OF LEVELS OF EVIDENCE OF CARCINOGENIC ACTIVITY 

ABSTRACT ......................................................... 

10 

5 

........... 

MATERIALSANDMETHODS 

INTRODUCTION 

SUMMARY OF TECHNICAL REPORTS REVIEW SUBCOMMITTEE COMMENTS 

TECHNICAL REPORTS REVIEW SUBCOMMITTEE 

37 

15 

12 

............................. 11 

......... 

..................................................... 

............................................ 

REFERENCES 

DISCUSSION AND CONCLUSIONS 

RESULTS .......................................................... 

105 

87 

49 

......................................... 

....................................................... 

APPENDIX A Summary of Lesions in Male Rats in the 2-Year Inhalation Study 

of Nickel Sulfate Hexahydrate ................................... 121 

APPENDIX B 

APPENDIX C 

APPENDIX D 

APPENDIX L 

APPENDIX K 

APPENDIX J 

APPENDIX I

APPENDIX H 

APPENDIX G 

APPENDIX F 

APPENDIX E

APPENDIX M 

of Nickel Sulfate Hexahydrate 

Summary of Lesions in Female Rats in the 2-Year Inhalation Study 

................................... 167 

of Nickel Sulfate Hexahydrate 

Summary of Lesions in Male Mice in the 2-Year Inhalation Study 

................................... 207 

of Nickel Sulfate Hexahydrate 

Summary of Lesions in Female Mice in the 2-Year Inhalation Study 

................................... 251 

Genetic Toxicology .......................................... 311 

Organ Weights and Organ-Weight-to-Body-Weight Ratios ................ 315 

Hematology Results ......................................... 327 

Tissue Burden in Rats ........................................ 335 

Tissue Burden in Mice ....................................... 341 

Reproductive Tissue Evaluations and Estrous Cycle Characterization ......... 347 

Chemical Characterization and Generation of Chamber Concentrations ....... 351 

in NIH-07 Rat and Mouse Ration 

Ingredients. Nutrient Composition. and Contaminant Levels 

................................ 369 

Sentinel Animal Program ..................................... 373 
5 

ABSTRACT 

NiSO,. 6H20 

NICKEL SULFATE HEXAHYDRATE 

CAS NO. 10101-97-0 

Chemical Formula: NiS04. 6H20 Molecular Weight: 262.86 

Synonyms: Blue salt; hexahydrate, nickel (2+) salt; nickel monosulfate hexahydrate; nickel (2+) sulfate hexahydrate; nickel (11) sulfate 

sulfuric acid 

hexahydrate; nickel sulphate hexahydrate; nickelous sulfate hexahydrate; nickelous sulphate hexahydrate; single nickel salt, 

were conducted in L5178Y mouse lymphoma cells. 

13 weeks, or 2 years. Genetic toxicology studies 

(greater than 98% pure) by inhalation for 16 days, 

mice were exposed to nickel sulfate hexahydrate 

exposure. Male and female F344/N rats and B6C3F, 

the toxic and carcinogenic effects of inhalation 

compounds for which there was little information on 

Institute to the NTP as part of a class study of nickel 

hexahydrate was nominated by the National Cancer 

manufacture of organic nickel salts. Nickel sulfate 

blackening agent for zinc and brass, and in the 

as a mordant in dyeing and printing textiles, as a 

Nickel sulfate hexahydrate is used in nickel plating, 

Final mean body weights of all exposed groups of 

60 mg/m3 females died before the end of the study. 

two 60 mg/m3 males, one 30 mg/m3 female, and all 

tissue burden studies. In the core study, 

3.5, 15, or 30 mg nickel sulfate hexahydrate/m3 for 

five male and female F344/N rats were exposed to 0, 

during a 16-day period. Additional groups of four or 

on weekdays only, for a total of 12 exposure days 

3.1, 6.1, or 12.2 mg nickel/m3). Rats were exposed 

sulfate hexahydrate/m3 (equivalent to 0, 0.7, 1.4, 

were exposed to 0, 3.5, 7, 15, 30, or 60 mg nickel 

Groups of five male and five female F344/N rats 

16-DAY STUDY IN RATS 

and females was greater than in control animals. 

nickel in the lungs of all exposed groups of males 

60 mg/m3 males and females. The concentration of 

lymph nodes was observed in 30 mg/m3 males and in 

Lymphoid hyperplasia in the bronchial or mediastinal 

60 mg/m3) and in 15, 30, and 60 mg/m3 females. 

passages of all exposed groups of males (except 

the olfactory epithelium occurred in the nasal 

all exposed groups of males and females. Atrophy of 

the bronchiolar epithelium) occurred in the lungs of 

Inflammation (including degeneration and necrosis of 

weights of all exposed groups of males and females. 

than those of the controls, as were the relative lung 

exposed groups of females were significantly greater 

Absolute lung weights of 60 mg/m3 males and of all 

exposure groups, except those exposed to 3.5 mg/m3. 

of respiration and reduced activity levels in rats in all 

male rats. Clinical findings included increased rates 

of the controls, as were mean body weight gains of 

males and females were significantly lower than those 

during a 16-day period. Additional groups of 

weekdays only, for a total of 12 exposure days 

sulfate hexahydrate/m3. Mice were exposed on 

were exposed to 0, 3.5, 7, 15, 30, or 60 mg nickel 

Groups of five male and five female B6C3F, mice 

16-DAY STUDY IN MICE 
6 Nickel Sulfate Hexahydrate, NTP TR 454 

3.5 mg/m3 were greater than those in the controls. 

concentrations in the lungs of mice exposed to 

observed in 3.5 mg/m3 males and females. Nickel 

the olfactory epithelium of the nasal passages was 

7 mg/m3 males and females. In addition, atrophy of 

epithelium was a component of the inflammation in 

females; necrosis of the alveolar and bronchiolar 

occurred in the lungs of 3.5 and 7 mg/m3 males and 

were examined histopathologically. Inflammation 

tissues from mice exposed to 0, 3.5, or 7 mg/m3 

significantly greater than those of the controls. Only 

female mice exposed to 7 mg/m3 or greater were 

Absolute and relative lung weights of male and 

ed emaciation, lethargy, and rapid respiration rates. 

controls, and clinical findings in these groups includfemales were significantly less than those of the 

weight gains of 7, 15, 30, and 60 mg/m3 males and 

end of the study. Final mean body weights and 

study; all control and 3.5 mg/m3 mice survived to the 

to 7 mg/m3 or greater died before the end of the 

tissue burden studies. All core study mice exposed 

to 0 or 3.5 mg nickel sulfate hexahydrate/m3 for 

five male and five female B6C3F, mice were exposed 

significantly greater than those of the controls. 

lung weights of all exposed groups were generally 

exception of 0.12 mg/m3 rats, absolute and relative 

were most pronounced in female rats. With the 

in neutrophil and lymphocyte numbers occurred and 

noted during the study. Exposure-related increases 

controls. There were no significant clinical findings 

all exposed groups were similar to those of the 

Final mean body weights and body weight gains of 

and all females survived until the end of the study. 

rat died before the end of the study; all other males 

burden studies. In the core study, one 2 mg/m3 male 

or 2 mg nickel sulfate hexahydrate/m3 for tissue 

six female F344/N rats were exposed to 0, 0.12,0.5, 

for 13 weeks. Additional groups of six male and 

0.11, 0.22, or 0.44 mg nickel/m3), 5 days per week 

sulfate hexahydrate (equivalent to 0, 0.03, 0.06, 

exposed to 0, 0.12, 0.25, 0.5, 1, or 2 mg nickel 

Groups of ten male and ten female F344/N rats were 

13-WEEK STUDY IN RATS 

13 weeks for males and at 13 weeks for females. 

that in the lungs of control animals at 4, 9, and 

the lungs of 0.5 and 2 mg/m3 rats was greater than 

0.25 mg/m3 females. The concentration of nickel in 

females exposed to 0.5, 1, and 2 mg/m3 and in 

of the olfactory epithelium occurred in males and 

in males exposed to 0.5 mg/m3 or greater. Atrophy 

bronchial and/or mediastinal lymph nodes occurred 

males and females. Lymphoid hyperplasia of the 

tion) occurred in the lungs of all exposed groups of 

phages, chronic inflammation, and interstitial infiltraseverity of inflammatory lesions (alveolar macroExposure-related increases in the incidence and 

control animals. 

of 2 mg/m3 females was significantly greater than in 

males and females. Nickel concentration in the lung 

in the nasal passages were observed in 2 mg/m3 

lymph node and atrophy of the olfactory epithelium 

females. Lymphoid hyperplasia of the bronchial 

and fibrosis occurred in 1 and 2 mg/m3 males and 

0.5 mg/m3 or greater. Chronic active inflammation 

phages occurred in all males and females exposed to 

the controls. Increased numbers of alveolar macroand females were significantly greater than those of 

lung weights of 1 mg/m3 males and 2 mg/m3 males 

were minimally affected. The absolute and relative 

female rats occurred in female mice, but the mice 

Hematology changes similar to those reported in 

There were no chemical-related clinical findings. 

exposed groups were similar to those of the controls. 

final mean body weights and body weight gains of all 

other mice survived to the end of the study. The 

were not considered to be chemical related, and all 

male died before the end of the study; the deaths 

males, three control females, and one 0.12 mg/m3 

tissue burden studies. In the core study, four control 

0.12, 0.5, or 2 mg nickel sulfate hexahydrate/m3 for 

male and female B6C3F, mice were exposed to 0, 

13 weeks. Additional groups of up to five or six 

nickel sulfate hexahydrate, 5 days per week for 

were exposed to 0, 0.12, 0.25, 0.5, 1, or 2 mg 

Groups of ten male and ten female B6C3F, mice 

13-WEEK STUDY IN MICE 
Nickel Sulfate Hexahydrate, N"P TR 454 7 

burden in the lung and kidney, and histopathology. 

15 months for alterations in hematology, nickel tissue 

five females from each group were evaluated at 

burden in the lung and kidney; and five males and 

group were evaluated at 7 months for nickel tissue 

tional seven males and seven females from each 

evaluated at 7 months for histopathology; an addiFive male and five female rats from each group were 

(8 minutes) 5 days per week for 104 weeks. 

Animals were exposed for 6 hours plus T, 

(equivalent to 0, 0.03, 0.06, or 0.11 mg nickel/m3). 

tion at concentrations of 0, 0.12, 0.25, or 0.5 mg/m3 

were exposed to nickel sulfate hexahydrate by inhalaGroups of 63 to 65 male and 63 to 64 female rats 

2-YEAR STUDY IN RATS 

nickel sulfate hexahydrate administration. 

ogy differences that were considered to be related to 

controls. There were no clinical findings or hematol0.25 mg/m3 females were similar to those of the 

weights of all exposed groups of males and 0.12 and 

out the second year of the study; final mean body 

lower (6% to 9%) than those of the controls throughbody weights of 0.5 mg/m3 female rats were slightly 

females were similar to those of the controls. Mean 

The survival rates of all exposed groups of males and 

and Hematology 

Survival, Body Weights, Clinical Findings, 

greater than those in controls at the end of the study. 

0.5 mg/m3 males and females were significantly 

incidences of atrophy of the olfactory epithelium in 

and female rats at the end of the 2-year study. The 

bronchial lymph nodes occurred in 0.5 mg/m3 male 

Increased incidences of lymphoid hyperplasia in the 

male and female rats exposed to 0.25 or 0.5 mg/m3. 

proteinosis, and fibrosis were markedly increased in 

inflammation, macrophage hyperplasia, alveolar 

of the study. The incidences of chronic active 

all exposed groups of male and female rats at the end 

inflammatory lung lesions were generally observed in 

hexahydrate for 2 years. Increased incidences of 

female rats exposed by inhalation to nickel sulfate 

No exposure-related neoplasms occurred in male or 

Pathology Findings 

were greater than those in the controls at the 7- and 

Lung nickel burdens in exposed male and female rats 

Tissue Burden Analyses 

concentration. 

dens values increased with increasing exposure 

15-month interim evaluations, and lung nickel burburden in the lung and kidney. 

group were evaluated at 15 months for nickel tissue 

pathology; and five males and five females from each 

15 months for alterations in hematology and histofive females from each group were evaluated at 

tissue burden in the lung and kidney; five males and 

each group were evaluated at 7 months for nickel 

histopathology; five males and five females from 

from each group were evaluated at 7 months for 

week for 104 weeks. Five male and five female mice 

exposed for 6 hours plus T, (8 minutes) 5 days per 

0.06, 0.11, or 0.22 mg nickel/m3). Animals were 

trations of 0, 0.25, 0.5, or 1 mg/m3 (equivalent to 0, 

to nickel sulfate hexahydrate by inhalation at concenGroups of 80 male and 80 female mice were exposed 

&YEAR STUDY IN MICE 

exposure. 

differences considered to be related to chemical 

There were no clinical findings or hematology 

the controls during the second year of the study. 

exposed groups of females were lower than those of 

mean body weights of 1 mg/m3 males and of all 

females were similar to those of the controls. The 

The survival rates of all exposed groups of males and 

and Hematology 

Survival, Body Weights, Clinical Findings, 

2-year study. 

and in all exposed groups of females at the end of the 

epithelium was observed in 0.5 and 1 mg/m3 males 

end of the 2-year study. Atrophy of the olfactory 

and females and in some 0.5 mg/m3 females at the 

bronchial lymph nodes of most of the 1 mg/m3 males 

plasia andlor lymphoid hyperplasia occurred in the 

the interstitium. Incidences of macrophage hyperplasia), alveolar proteinosis, and infiltrating cells in 

tion, bronchialization (alveolar epithelial hypermacrophage hyperplasia, chronic active inflammaend of the 2-year study. These lesions included 

in all exposed groups of male and female mice at the 

Inflammatory lesions of the lung generally occurred 

Pathology Findings 
8 Nickel Sulfate Hexahydrate, NTP TR 454 

those of the controls at 15 months. 

burden study females were significantly greater than 

Absolute lung weights of 0.5 and 1 mg/m3 lung 

exposed groups were below the limit of detection. 

nickel burden parameters measured in control and 

At the 7- and 15-month interim evaluations, lung 

Tissue Burden Analyses 

GENETIC TOXICOLOGY 

test was not performed with S9. 

response was observed in the absence of S9. The 

in L5178Y mouse lymphoma cells. A positive 

tested for induction of trifluorothymidine resistance 

Nickel sulfate hexahydrate (500 to 800 pg/mL) was 

CONCLUSIONS 

activity* of nickel sulfate hexahydrate in male or 

studies, there was no evidence of carcinogenic 

Under the conditions of these 2-year inhalation 

or 0.22 mg nickel/m3). 

mice exposed to 0.25, 0.5, or 1 mg/m3 (0.06, 0.11, 

nickel sulfate hexahydrate in male or female B6C3F, 

There was no evidence of carcinogenic activity of 

0.5 mg/m3 (0.03, 0.06, or 0.11 mg nickel/m3). 

female F344/N rats exposed to 0.12, 0.25, or 

epithelium. 

bronchial lymph node; and atrophy of the olfactory 

lung; lymphoid and macrophage hyperplasia of the 

interstitial infiltration, and alveolar proteinosis of the 

epithelial hyperplasia), macrophage hyperplasia, 

active inflammation, bronchialization (alveolar 

2 years resulted in increased incidences of chronic 

mice to nickel sulfate hexahydrate by inhalation for 

and atrophy of the olfactory epithelium. Exposure of 

lymphoid hyperplasia of the bronchial lymph node; 

plasia, alveolar proteinosis, and fibrosis of the lung; 

of chronic active inflammation, macrophage hyperinhalation for 2 years resulted in increased incidences 

Exposure of rats to nickel sulfate hexahydrate by 

* Explanation of Levels of Evidence of Carcinogenic Activity is on page 10. A summary of the Technical Reports Review Subcommittee 

comments and the public discussion on this Technical Report appears on page 12. 
Nickel Sulfate Hexahydrate, NTP TR 454 9 

Summary of the 2-Year Carcinogenesis and Genetic Toxicology Studies of Nickel Sulfate Hexahydrate 

Male Female Male Female 

F344/N Rats F344/N Rats B6C3F, Mice B6C3Fl Mice 

Exposure 0, 0.12, 0.25, or 

0.11 mg nickel/m3) 

to 0, 0.03. 0.06. or concentrations 0.5 mg/m3 (equivalent 

to controls 

Body weights Exposed groups similar 

2-Year survival 16/54, 16/53, 18/53, 

rates 21/53 

11/53, 42/53, 46/53); 

effects inflammation (14/54, 

Nonneoplastic Luna: chronic active 

(0/54, 0/52, 3/53, 7/53) 

epithelium): atrophy 

Nose (olfactory 

10/52) 

(0/51, 0/49, 3/47, 

lymphoid hyperplasia 

Bronchial lymph node: 

43/53) 

(3/54, 6/53, 35/53, 

12/53, 41/53); fibrosis 

proteinosis (0154, 0/53, 

48/53); alveolar 

(7/54, 9/53, 35/53, 

macrophage hyperplasia 

0.11 mg nickel/m3) 

to 0, 0.03, 0.06, or 

0.5 mg/m3 (equivalent 

0, 0.12, 0.25, or 

than controls 

0.5 mg/m3 group lower 

29/55 

22/53, 17/53, 28/54, 

(0151, 1/52, 1/53, 7/54) 

epithelium): atrophy 

Nose (olfactory 

1 1/49) 

(2/50, 1/52, 0151, 

lymphoid hyperplasia 

Bronchial lymph node: 

49/54) 

(8/52, 7/53, 45/53, 

22/53, 49/54); fibrosis 

proteinosis (1152, 0/53, 

45/54); alveolar 

(9/52, 10/53, 32/53, 

macrophage hyperplasia 

13/53, 49/53, 52/54); 

inflammation (14/52, 

m: chronic active 

Neoplastic effects None None 

carcinogenic activity 

Level of evidence of No evidence No evidence 

0.22 mg nickel/m3) 

0, 0.06, 0.11, or 

1 rng/m3 (equivalent to 

0, 0.25, 0.5, or 

than controls 

1 rng/m3 group lower 

25/62 

26/61, 23/61, 24/62, 

37/60) 

(0/61, 0/61, 12/61, 

epithelium): atrophy 

Nose (olfactory 

8/45, 39/54) 

hyperplasia (0/46, 0149, 

17/54); macrophage 

(2/46, 4/49, 2/45, 

lymphoid hyperplasia 

Bronchial lvmph node: 

0162, 42/61) 

proteinosis (0/61, 0/61, 

3/62, 17/61); alveolar 

infiltration (1161, 0161, 

59/61); interstitial 

(6/61, 9/61, 35/62, 

macrophage hyperplasia 

4/61, 19/62, 39/61); 

bronchialization (1/61, 

2/61, 8/62, 29/61); 

inflammation (1161. 

Luna: chronic active 

None 

No evidence 

0.22 mg nickel/m3) 

0, 0.06, 0.11, or 

1 mg/m3 (equivalent to 

0, 0.25, 0.5, or 

than controls 

Exposed groups lower 

37/60 

34/61, 39/60, 45/60, 

17/60) 

(3/61, 2/59, 1/60, 

epithelium): atrophy 

Nose (olfactory 

14/58, 37/56) 

hyperplasia (2/50, 0154, 

26/56); macrophage 

(15150, 9/54, 16/58, 

lymphoid hyperplasia 

Bronchial lvmph node: 

11/60, 45/60) 

proteinosis (0161. 0160, 

16/60, 39/60); alveolar 

infiltration (0161. 4/60, 

59/60); interstitial 

(7161, 24/60, 53/60, 

macrophage hyperplasia 

9/60, 32/60, 45/60); 

bronchialization (0161, 

7/60, 14/60, 40/60); 

inflammation (1161, 

h: chronic active 

None 

No evidence 

Genetic toxicology 

L5178Y mouse lymphoma cells gene mutations: Positive without S9 
10 Nickel Sulfate Hexahydrate, NTP TR 454 

EXPLANATION OF LEVELS OF EVIDENCE OF CARCINOGENIC ACTIVITY 

chemicals found to be carcinogenic in laboratory animals requires a wider analysis that extends beyond the purview of these studies. 

those conducted by the NTP, epidemiologic studies, and estimates of exposure. Thus, the actual determination of risk to humans from 

Cancer, assign a strength of evidence for conclusions based on an examination of all available evidence, including animal studies such as 

that exposure to the chemical has the potential for hazard to humans. Other organizations, such as the International Agency for Research on 

conditions. Positive results demonstrate that a chemical is carcinogenic for laboratory animals under the conditions of the study and indicate 

animals, do not necessarily mean that a chemical is not a carcinogen, inasmuch as the experiments are conducted under a limited set of 

for conclusions regarding each study. Negative results, in which the study animals do not have a greater incidence of neoplasia than control 

The National Toxicology Program describes the results of individual experiments on a chemical agent and notes the strength of the evidence 

selected to describe the findings. These categories refer to the strength of the experimental evidence and not to potency or mechanism. 

carcinogenic activity. For each separate experiment (male rats, female rats, male mice, female mice), one of the following five categories is 

in March 1986 for use in the Technical Report series to incorporate more specifically the concept of actual weight of evidence of 

because of major flaws (inadequate study). These categories of interpretative conclusions were first adopted in June 1983 and then revised 

(equivocal evidence); one category for no observable effects (no evidence); and one category for experiments that cannot be evaluated 

observed in each experiment: two categories for positive results (clear evidence and some evidence); one category for uncertain findings 

Five categories of evidence of carcinogenic activity are used in the Technical Report series to summarize the strength of the evidence 

l Clear evidence of carcinogenic activity is demonstrated by studies that are interpreted as showing a dose-related 

increased incidence of neoplasms (malignant, benign, or combined) in which the strength of the response is less than that 

of benign neoplasms if there is an indication from this or other studies of the ability of such tumors to progress to malignancy. 

(i) increase of malignant neoplasms, (ii) increase of a combination of malignant and benign neoplasms, or (iii) marked increase 

limitations, cannot be interpreted as valid for showing either the presence or absence of carcinogenic activity. 

increases in malignant or benign neoplasms. 

of neoplasms that may be chemical related. 

required for clear evidence. 

l Some evidence of carcinogenic activity is demonstrated by studies that are interpreted as showing a chemical-related 

l Inadequate study of carcinogenic activity is demonstrated by studies that, because of major qualitative or quantitative 

l No evidence of carcinogenic activity is demonstrated by studies that are interpreted as showing no chemical-related 

l Equivocal evidence of carcinogenic activity is demonstrated by studies that are interpreted as showing a marginal increase 

between two adjacent levels. These considerations should include: 

understanding of long-term carcinogenesis studies in laboratory animals, especially for those evaluations that may be on the borderline 

boundary of an individual category of evidence. Such consideration should allow for incorporation of scientific experience and current 

When a conclusion statement for a particular experiment is selected, consideration must be given to key factors that would extend the actual 

l adequacy of the experimental design and conduct; l occurrence of common versus uncommon neoplasia; l progression (or lack thereof) from benign to malignant neoplasia as well as from preneoplastic to neoplastic lesions: 

l some benign neoplasms have the capacity to regress but others (of the same morphologic type) progress. At present, it is 

l combining benign and malignant tumor incidence known or thought to represent stages of progression in the same organ or 

is to assume that benign neoplasms of those types have the potential to become malignant; 

impossible to identify the difference. Therefore, where progression is known to be a possibility, the most prudent course 

l supporting information from proliferative lesions (hyperplasia) in the same site of neoplasia or in other experiments (same 

l metastases; 

l multiplicity in site-specific neoplasia; 

l latency in tumor induction; 

tissue; 

l presence or absence of dose relationships; l statistical significance of the observed tumor increase; 

l concurrent control tumor incidence as well as the historical control rate and variability for a specific neoplasm; l survival-adjusted analyses and false positive or false negative concerns; 

l structure-activity correlations; and l in some cases, genetic toxicology. 

lesion in another sex or species); 
Nickel Sulfate Hexahydrate, NTP TR 454 11 

TECHNICAL REPORTS REVIEW SUBCOMMITTEE 

NATIONAL TOXICOLOGY PROGRAM BOARD OF SCIENTIFIC COUNSELORS 

company, or governmental agency. In this capacity, subcommittee members have five major responsibilities in reviewing NTP studies: 

on November 29, 1994, are listed below. Subcommittee members serve as independent scientists, not as representatives of any institution, 

The members of the Technical Reports Review Subcommittee who evaluated the draft NTP Technical Report on nickel sulfate hexahydrate 

l to ascertain that all relevant literature data have been adequately cited and interpreted, l to determine iEthe design and conditions of the NTP studies were appropriate, l to ensure that the Technical Report presents the experimental results and conclusions fully and clearly, l to judge the significance of the experimental results by scientific criteria, and l to assess the evaluation of the evidence of carcinogenic activity and other observed toxic responses. 

Arnold L. Brown, M.D., Chair 

Madison, WI 

University of Wisconsin Medical School 

Thomas L. Goldsworthy, Ph.D., Principal Reviewer 

Research Triangle Park, NC 

Chemical Industry Institute of Toxicology 

Department of Environmental Pathology and Toxicology 

Meryl H. Karol, Ph.D.* 

Pittsburgh, PA 

University of Pittsburgh 

Department of Environmental Occupational Health 

Curtis D. Klaassen, Ph.D. 

Kansas City, KS 

University of Kansas Medical Center 

Department of Pharmacology and Toxicology 

Claudia S. Miller, M.D. 

San Antonio, TX 

University of Texas Health Sciences Center 

Irma RUSSO , M .D . , Principal Reviewer 

Philadelphia, PA 

Fox Chase Cancer Center 

Louise Ryan, Ph.D. 

Boston, MA 

Dana-Farber Cancer Institute 

Harvard School of Public Health and 

Division of Biostatistics 

Robert E. Taylor, M.D., Ph.D., Principal Reviewer 

Washington, DC 

Howard University College of Medicine 

Department of Pharmacology 

Mary Jo Vodicnik, Ph.D.* 

Belgium 

Lilly MSG Development Center 

Jerrold M. Ward, D.V.M., Ph.D. 

Frederick, MD 

National Cancer Institute 

Janardan K. Reddy, M.D.* 

Chicago, IL 

Northwestern University Medical School 

Department of Pathology 

* Did not attend 
12 Nickel Sulfate Hexahydrate, NTP TR 454 

SUMMARY OF TECHNICAL REPORTS REVIEW SUBCOMMITTEE COMMENTS 

Triangle Park, NC. 

Institute of Environmental Health Sciences, Research 

tee. The review meeting was held at the National 

Counselors’ Technical Reports Review SubcommitNational Toxicology Program’s Board of Scientific 

sulfate hexahydrate received public review by the 

on the toxicology and carcinogenesis studies of nickel 

On November 29, 1994, the draft Technical Report 

in male and female B6C3F, mice. 

F344/N rats and no evidence of carcinogenic activity 

evidence of carcinogenic activity in male and female 

rats and mice. The proposed conclusions were no 

plasms and nonneoplastic lesions in male and female 

effects, and commenting on compound-related neodesign, reporting on survival and body weight 

rationale for study, describing the experimental 

hydrate by discussing the uses of the chemical and 

and carcinogenesis studies of nickel sulfate hexaDr. J.K. Dunnick, NIEHS, introduced the toxicology 

concentrations could have been slightly higher. 

proposed conclusions. He said that he exposure 

Dr. Taylor, a principal reviewer, agreed with the 

Dr. J.R. Bucher, NIEHS, explained that lung burden 

data and comparison to other nickel studies. 

linkages could not be made, limiting extrapolation of 

concentration in mice, and thus, exposure-response 

concentrations were not observed at any exposure 

Dr. Goldsworthy said that target tissue (lung) nickel 

exceeding the maximum tolerated dose. 

higher exposure concentration might have resulted in 

Based on body weight decreases, he believed that a 

that in high dose animals in the nickel oxide study. 

morphologic appearance of the lungs being similar to 

commented that he high dose was based on the 

some circumstances. Dr. M.R. Elwell, NIEHS, 

2 years, including no target tissue weight changes in 

13 weeks resulted in minimal to mild changes at 

tions elected for minimal to mild responses at 

Dr. Goldsworthy observed that exposure concentramight have ben higher, especially in mice. 

also thought the exposure concentrations selected 

agreed with the proposed conclusions although he 

Dr. Goldsworthy, the second principal reviewer, 

body weight gain. 

inflammatory changes in the lung and decreases in 

all exposure concentrations were selected based on 

particular dose. This did not occur, so in this case 

i.e., an overload condition was reached with a 

chronic studies there had been a non-linear increase, 

information would have been used if in the prelymphoma. 

reaction, versus monoclonal proliferation or early 

either a reactive hyperplasia or a granulomatous 

prove that the lesions represented a reactive process, 

node hyperplasia should be documented in order to 

the proposed conclusions. She stated that the lymph 

Dr. Russo, the third principal reviewer, agreed with 

across organs and species. 

toxicokinetic profiles to enable better comparisons 

designs is incorporating mechanistic markers or 

illustrate why the NTP in its more recent study 

one compares studies across a class of chemicals 

that the discussions regarding dose selection and how 

pulmonary function. Dr. G.W. Lucier, NIEHS, said 

and inhaled toxicants should be more concerned‘with 

relate to carcinogenicity, future studies with metals 

commented again that since toxicity did not predict or 

enhance ancer development. Dr. Goldsworthy 

result in concurrent biologic events that might 

sures in the workplace and speculated that this could 

Dr. Dunnick noted the evidence for multiple expoin the NTP animal studies by the inhalation route. 

not provide stronger evidence of carcinogenic activity 

epidemiological data that the nickel compounds did 

Dr. Klaassen expressed surprise in view of the 

could be made that current regulations are not 

report were based on existing TLVs, an implication 

Ms. Sivulka said that because conclusions in the 

relative to existing threshold limit values (TLVs). 

the presentation of the significance of findings 

for nickel toxicity and carcinogenesis in humans and 

(NiPERA), commented on the discussion of evidence 

Producers Environmental Research Association, Inc. 

Ms. D. Sivulka, executive director of the Nickel 
Nickel Sulfate Hexahydrate, NTP TR 454 13 

protective of workers exposed to nickel compounds. Dr. Taylor moved that the Technical Report on 

Ms. Sivulka discussed the cohorts of workers nickel sulfate hexahydrate be accepted with the 

exposed to nickel compounds that have been exam- revisions discussed and with the conclusions as 

ined, and she said that the information obtained from written for male and female rats and mice, no evithese examinations shows no evidence of nickel- dence of carcinogenic activity. Dr. Klaassen 

related increases in the incidence of nonneoplastic seconded the motion, which was accepted unanilesions in workers exposed to low nickel levels. mously with seven votes. 
14 Nickel Sulfate Hexahydrate, NTP TR 454 
15 

INTRODUCTION 

NiSO,. 6H,O 

NICKEL SULFATE HEXAHYDRATE 

CAS NO. 10101-97-0 

Chemical Formula: NiS04. 6H20 Molecular Weight: 262.86 

sulfuric acid 

hexahydrate; nickel sulphate hexahydrate; nickelous sulfate hexahydrate; nickelous sulphate hexahydrate; single nickel salt, 

Synonyms: Blue salt; hexahydrate, nickel (2+) salt; nickel monosulfate hexahydrate; nickel (2+) sulfate hexahydrate; nickel (11) sulfate 

CHEMICAL AND PHYSICAL PROPERTIES 

these 2-year studies ranged from 2.2 to 2.5 pm. 

concentration of nickel sulfate hexaydrate used in 

median aerodynamic diameter at each exposure 

(Merck Index, 1989). The mean value for the mass 

melting point of 53.3 O C and a density of 2.07 g/cm3 

powder) is a water-soluble nickel compound with a 

Nickel sulfate hexahydrate (a blue-green crystalline 

(900,000 metric tons) (U.S. Bureau of Mines, 1991). 

production of nickel is estimated at 1,000,000 tons 

extracted from oxide ore. The total annual world 

extracted from sulfide ore, and the remainder is 

Approximately 55% of the nickel currently used is 

Australia, New Caledonia, Indonesia, and Cuba. 

producing countries were the Soviet Union, Canada, 

Mines, 1984, 1985a). In 1991, the six largest nickel 

(NIOSH, 1977; Warner, 1984; U.S. Bureau of 

ily as an oxide (laterite) or sulfide ore (pentlandite) 

Nickel was first isolated in 1751 and is found primarAND HUMAN EXPOSURE 

PRODUCTION, USE, 

(U.S. Bureau of Mines, 1991). The United States 

mately 200,000 tons (180,000 metric tons) annually 

The United States consumption of nickel is approxi18,165 to nickel oxide (NIOSH, 1991). 

are potentially exposed to nickel sulfate and 

Survey reported that 56,843 United States workers 

1984, 1985b). The National Occupational Exposure 

and other forms (2.1%) (U.S. Bureau of Mines, 

(17.3%), nickel oxide (11.4%), nickel salts (1.2%), 

consumes unwrought nickel (68 %), ferronickel 

(U.S. Bureau of Mines, 1984). 

household appliances, machinery, and ships and boats 

and parts, construction, fabricated metal products, 

refining, electrical equipment and supplies, aircraft 

chemicals and allied products and in petroleum 

resistance and strength leads to its wide use in 

8% nickel. The ability of nickel to impart corrosion 

stainless steel (Warner, 1984), which contains up to 

Half of the nickel sold per year is used to make 

water include hydrated nickels (ATSDR, 1992). The 

nickel sulfate, and the most probable species found in 

sphere include complex nickel, nickel oxide, and 

most probable nickel species present in the atmoair has been found to range from 1 to 86 ng/m3. The 

than 10 ppb. Nickel concentration in United States 

tration of nickel in finished drinking water is less 

food, and household objects. The average concenLow levels of nickel are found in air, soil, water, 

Nickel constitutes about 0.008% of the earth’s crust. 
16 Nickel Sulfate Hexahydrate, NTP TR 454 

(Fed. Regist., 1987). 

chemical in waste disposal sites in the United States 

1992). Nickel is listed as a frequently occurring 

drinking water is estimated at 2 pg per day (ATSDR, 

day (excluding cigarette smoke), and intake from 

from inhalation is estimated at 0.1 to 1 pg nickel per 

from foods is estimated at 170 pg per day; intake 

et ai., 1985). Dietary intake of nickel per person 

day, 40 hours per week (NIOSH, 1977). 

averaged over a work shift of up to 10 hours per 

limit for nickel be reduced to 0.015 mg nickel/m3 

Health recommended that the permissible exposure 

The National Institute for Occupational Safety and 

water-insoluble nickel compounds (ACGIH, 1993). 

change to 0.05 mg nickel/m3 for water-soluble and 

but the ACGIH published notice of an intended 

insoluble salts and 0.1 mg/m3 for water-soluble salts, 

(ACGIH) are 1 mg/m3 for nickel metal and waterConference of Governmental Industrial Hygienists 

The threshold limit values adopted by the American 

rence of individual nickel species (ATSDR, 1992). 

trial exposure report total nickel and not the occurpresent, and most studies of environmental or industotal nickel without discerning the forms of nickel 

in the workplace. This method of analysis measures 

method for quantifying nickel in the environment and 

Atomic absorption spectroscopy is a widely used 

ABSORPTION, DISTRIBUTION, 

exposure (water-soluble forms of nickel). 

exposure (water-soluble forms of nickel), and dermal 

soluble and water-insoluble forms of nickel), oral 

excretion of nickel after inhalation exposure (waterinformation on the absorption, distribution, and 

Animal model systems have been used to obtain 

Experimental Animals 

AND EXCRETION 

tion, was excreted primarily in the urine. After 

Wistar rats. Nickel, after nickel chloride administratemperature nickel oxide calcined at 250" C) in 

labeled nickel chloride or nickel oxide (low 

study after intratracheal administration of [63Ni]- 

et ai. (1981) reported on a comparative toxicokinetic 

fate of specific forms of nickel in the lung. English 

one method used by several investigators to study the 

Intratracheal administration of nickel compounds was 

lungs within 3 days. 

with greater than 50% of the nickel cleared from the 

nickel chloride was rapidly excreted from the lung 

persisted in the lung for more than 90 days, while 

excreted in the feces and urine. Nickel oxide 

nickel oxide administration, nickel was equally 

in the urine (Carvalho and Ziemer, 1982). 

0.1 % on day 21 ; 96% of the chemical was excreted 

of their initial burden at day 1, and this decreased to 

eliminated from the lungs. The lungs retained 29% 

urine. By day 3, 90% of the instilled chemical was 

to Sprague-Dawley rats was excreted primarily in the 

Nickel chloride administered as an intratracheal dose 

et ai., 1987). 

phase and i 19 hours for the second phase (Finch 

with a clearance half-life of 2 hours for the first 

administered intratracheally to mice was also biphasic 

the calculated clearance times of nickel subsulfide 

(Valentine and Fisher, 1984). In another experiment, 

after 3 days with 33% appearing in the urine 

the feces; 57 % of the administered dose was excreted 

(measured as 63Ni) was 60% in the urine and 40% in 

respectively. The excretion of thechemical 

half-lives corresponding to 1.2 and 12.4 days, 

distinct components with initial and final biological 

tered nickel subsulfide (Ni,S,) in mice has two 

The pulmonary clearance of intratracheally adminis- 

(Medinsky et al., 1987). 

urine was the major route for excretion of nickel 

tissues (including blood, kidney, and intestine), and 

3 days, nickel was present in extrarespiratory tract 

administered to F344/N rats intratracheally was 1 to 

feces. The half-life of [63Ni]-labeled nickel sulfate 

kidney, and nickel was excreted in the urine and the 

extrarespiratory tract tissue including blood and 

nickel subsulfide exposure, nickel was detected in 

first few days after exposure. In contrast, after 

material was only excreted in the feces during the 

distributed to the extrarespiratory tract tissue, and the 

Following nickel oxide exposure, nickel was not 

5 days for nickel subsulfide (Benson et al., 1994). 

was estimated at 120 days for nickel oxide and 

subsulfide by pernasal inhalation, the lung half-life 

oxide (high temperature, green oxide) or nickel 

In F344/N rats administered [63Ni]-labeled nickel 
Introduction 17 

1 year. 

to nickel oxide, a steady state would be reached after 

et al. (1980) estimated that with continuous exposure 

of 36 days (Hochrainer et al., 1980). Hochrainer 

half-life of 1 day and an alveolar clearance half-life 

750 pg/m3 to Wistar rats had a bronchial clearance 

deviation [a,] of 1.5) given as an aerosol of 

diameter ["AD] of 0.15 pm, geometric standard 

oxide (formed at 550" C; mass median aerodynamic 

relatively long half-life in the rodent lung. Nickel 

Other studies also indicated that nickel oxide has a 

respectively (Tanaka et al., 1985, 1988). 

particulate MMADs of 0.6, 1.2, and 4.0 pm, 

be 8, 1 1, and 21 months for nickel oxide with 

in Wistar rats exposed for 1 month were estimated to 

lives for nickel oxide (high temperature, green oxide) 

blood (Kodama et al., 1985). Lung clearance halfof nickel in the liver, kidney, spleen, heart, brain, or 

100 pg per year. There was no apparent deposition 

2 months, the lung clearance was estimated to be 

1.2 pm, ag of 2.5) for 6 to 7 hours per day for 1 to 

oxide/m3 (high temperature, green oxide; "AD of 

In Wistar rats after exposure to 0.6 or 8.0 mg nickel 

nickel oxide. 

sulfate or nickel subsulfide, but not after exposure to 

extrarespiratory tract tissue after exposure to nickel 

100 days for nickel oxide. Nickel was detected in 

sulfate, 5 days for nickel subsulfide, and greater than 

exposure, the lung half-life was 1 to 3 days for nickel 

nickel administered intratracheally or by inhalation 

In summary, in absorption and distribution studies for 

(Benson et al., 1987; Dunnick et al., 1989). 

subsulfide, and ,the longest half-life for nickel oxide. 

sulfate hexahydrate, a longer half-life for nickel 

show a relatively short half-life in the lung for nickel 

7 and 15 months in the 2-year studies. These data 

of rats and mice after 16 days, 13 weeks, and at 

subsulfide, and nickel oxide in the lungs and tissues 

deposition of nickel sulfate hexahydrate, nickel 

The present studies also report findings on the 

mice, and dogs indicate that 1 % to 10% was 

Studies of other routes of nickel exposure in rats, 

et al., 1993). 

guinea pigs within 24 hours (ATSDR, 1992; Nielsen 

nickel chloride was absorbed through the skin of 

hexahydrate or nickel chloride, and less than 1 % of 

absorbed after oral administration of nickel sulfate 

and Andersen, 1979; Boysen et al., 1984). 

workers were exposed was not identified (Torjussen 

although the specific form of nickel to which these 

retired workers years after cessation of employment, 

plasma, and nasal mucosa biopsies obtained from 

elevated nickel concentrations in specimens of urine, 

of time (Morgan and Rouge, 1983). There were 

depots in the body that retain nickel for long periods 

facility closing, indicating that there are storage 

of workers for periods of up to 6 months after 

Oskarsson, 1991). Nickel was excreted in the urine 

(Bennet, 1984; Grandjean, 1984; Sunderman and 

absorbed into the blood from the respiratory tract 

1992); it is estimated that 35% of inhaled nickel is 

exposure in humans is by inhalation (Sunderman, 

In the industrial setting, a major route of nickel 

Humans 

for levels of total nickel. 

is monitored by analyzing urine, hair, or fingernails 

cancer. In .the workplace setting, exposure to nickel 

lung at autopsy as those who died of other types of 

cancer had the same concentrations of nickel in the 

although workers who were diagnosed as having lung 

nickel in the lungs of nickel refinery workers, 

Andersen and Svenes (1989) found elevated levels of 

sulfate to 3 % for nickel chloride (ATSDR, 1992). 

occluded skin varied from 55 % to 77% for nickel 

reported absorption of radioactive nickel applied to 

(Sunderman, 1989, .1992). In studies in humans, 

nated in either the feces or urine within 4 days 

28 hours; 100% of the absorbed nickel was elimielimination half-life for absorbed nickel averaged 

0.7% was absorbed when administered in food. The 

absorbed when given in drinking water, while only 

human volunteers, 27 % of the administered dose was 

When nickel sulfate was administered to fasting 
18 Nickel Sulfate Hexahydrate, NTP TR 454 

TOXICITY 

occurred in the respiratory system. 

primary toxic response to nickel after inhalation 

1992). In experimental animals and in humans, the 

WHO, 1991 ; ATSDR, 1992; Nieboer and Nriagu, 

USEPA, 1986; European Chemical Industry, 1989; 

1990; NIOSH, 1977; Brown and Sunderman, 1985; 

reviews (NAS, 1975; IARC, 1976, 1984, 1987, 

industrial exposure have been summarized in various 

Studies of nickel toxicity after experimental or 

and greater than 11 years for nickel oxide 

dissolution half-life is 23 days for nickel subsulfide 

11 years, respectively. In rat serum, the estimated 

and nickel oxide in water are greater than 7 or 

lives (based on in vitro studies) for nickel subsulfide 

have been reported. The calculated dissolution halfsubsulfide and nickel oxide in water and rat serum 

Information on the dissolution half-lives for nickel 

fluids. 

parallels the solubility of the compounds in biological 

hexahydrate, nickel subsulfide, and nickel oxide 

1983). The comparative toxicity of nickel sulfate 

human serum than nickel subsulfide (Kasprzak et al., 

hydroxide) have been shown to be more soluble in 

oxide in biological fluids. Soluble nickel salts (nickel 

water, nickel subsulfide is more soluble than nickel 

and nickel oxide are both relatively insoluble in 

(Sunderman et al., 1987). While nickel subsulfide 

Experimental Animals 

place. 

or nickel subsulfide is more common in the workExposure to nickel oxide, nickel sulfate hexahydrate, 

manufacturing processes is limited (NAS, 1975). 

but the use or formation of this nickel compound in 

[Ni(CO),] is the most acutely toxic form of nickel, 

pounds are summarized in Table 1. Nickel carbonyl 

The acute toxicity values for selected nickel comand Nickel Subsulfidea 

Toxicity Values for Nickel Carbonyl, Nickel Oxide, Nickel Sulfate Hexahydrate, Nickel Sulfate, 

TABLE 1

Nickel Compound Species Route Toxicity Valueb 

Nickel carbonyl 

Nickel oxide 

Rat 

Rabbit 

Cat 

Dog 

Mouse 

Rat 

Mouse 

Intraperitoneal 

Intravenous 

Subcutaneous 

Inhalation 

Inhalation 

Inhalation 

Inhalation 

Inhalation 

Intratracheal 

Intramuscular 

Subcutaneous 

Intraperitoneal 

Subcutaneous 

35 ppm 

1,890 mg/m' (LC,,,) 

360 ppm (LCLo) 

67 mg/m' (LC,,,) 

39 mg/kg (LDS") 

63 Mkg (LDd 

66 mg/kg (LD,) 

73 g/m' (LCLo) 

400 mg/kg (TDLo) 

50 mg/kg (LD,) 

(continued) 
Introduction 19 

and Nickel Subsulfide (continued) 

Toxicity Values for Nickel Carbonyl, Nickel Oxide, Nickel Sulfate Hexahydrate, Nickel Sulfate, 

TABLE 1 

Nickel Compound Species Route Toxicity Value 

Nickel sulfate hexahydrate Dog 

Cat 

Intravenous 

Subcutaneous 

72 mglkg (LDLo) 

500 mglkg (LDLo) 

89 mglkg (LDLo) 

500 mglkg (LDLo) 

Intravenous 

Subcutaneous 

Rabbit 

62 mglkg (LDLo) 

36 mglkg (LDLo) 

500 mglkg (LDLo) 

Intravenous 

subcutaneous 

Guinea pig Subcutaneous 

Nickel sulfate 

Mouse 

Rat 

Intravenous 

Intraperitoneal 

Intraperitoneal 

Intravenous 

Subcutaneous 

24 mglkg (LDLo) 

38 mglkg (LDLo) 

38 mglkg (LDLo) 

Rabbit 

Cat Subcutaneous 

Intravenous 

Subcutaneous 

33 mglkg (LDLo) 

33 mglkg (LDLo) 

Nickel subsulfide Rat 

Intramuscular 

Intravenous 

Subcutaneous 

Inhalation 

20 mglkg (TDLo) 

10 mglkg (TDLo) 

125 mglkg (TDLo) 

1 mglkg (TCLo) 

Mouse Intramuscular 200 mglkg (TDLo) 

a From RTECS (1987) 

TCLo = lowest toxic concentration; TDLo = lowest toxic dose. 

LCs, = median lethal concentration; LCLo = lowest lethal concentration; LDS,) = median lethal dose; LDLo = lowest lethal dose; 

1980). 

cleaning and feeding periods) (Weischer et al., 

400, or 800 pglm3 for 120 days (except for daily 

rats continuously exposed to nickel oxide at 200, 

increased erythrocyte count, were observed in Wistar 

count, increased urine alkaline phosphatase, and 

related reduced body weight, reduced leukocyte 

Changes in a variety of parameters, including dosetoxic response is seen in the respiratory system. 

and water-insoluble nickel compounds, the primary 

In animals, after inhalation exposure to water-soluble 

tures consistent with accumulation of phospholipid 

particles as well as membranous and lamellar strucphagosomes contained osmophilic nickel oxide 

In the cytoplasm of alveolar macrophages, 

animals were increased in number and enlarged. 

to controls, alveolar macrophages from exposed 

were examined by electron microscopy. Compared 

by intratracheal injection (10 mg nickel oxide/mL) 

12 hours per day, 6 days per week, for 28 days or 

rats exposed to nickel oxide at 120 pg/m3 for 

Alveolar macrophages from lung lavage fluid from 
20 Nickel Sulfate Hexahydrate, lV" TR 454 

Niklowitz, 1983). 

material (Migally et al., 1982; Murthy and 

in lung lavage fluid (Benson et al., 1989). 

looking for treatment-related markers of lung toxicity 

hexahydrate, or nickel subsulfide for 13 weeks and 

exposing rats or mice to nickel oxide, nickel sulfate 

sialic acid. This evaluation was continued by 

glutathione reductase, glutathione peroxidase, and 

lactate dehydrogenase, @-glucuronidase, total protein, 

in the following parameters in lung lavage fluid: 

hexahydrate, or nickel chloride, there were increases 

After exposure to nickel subsulfide, nickel sulfate 

lavage fluid were seen after exposure to nickel oxide. 

(Benson et al., 1986). No significant changes in lung 

treatment-related changes in lung lavage fluid 

tracheal instillation was evaluated by examining 

chloride, nickel sulfate, or nickel oxide by intrasingle dose of either nickel subsulfide, nickel 

Respiratory toxicity to F344/Crl rats administered a 

TABLE 2 

(Benson et al., 1989). 

toxic, and ickel oxide was the least toxic 

the lung. Nickel sulfate hexahydrate was the most 

fluid paralleled the severity of histologic changes in 

toxicity as measured by the changes in lung lavage 

three nickel compounds. The severity of lung 

in the lung of rats and mice exposed to each of the 

response. Inflammation was observed histologically 

quantitative differences in the magnitude of the 

three nickel compounds, although there were 

the lavage fluid after exposure of rats and mice to all 

number, and macrophage number were observed in 

Increases in @-glucuronidase, total protein, neutrophil 

ments (Table 2). 

been studied under various conditions and experilocal and systemic immunity, and this toxicity has 

water-insoluble nickel salts may cause an alteration of 

Treatment of rats and mice with water-soluble and 

Nickel Compound SpecieslRoute Treatment 

Studies on the Immunologic Effects of Nickel Compounds 

Response Reference 

Cell-Mediated Immunity 

Nickel chloride 

on spleen cells 

Guinea pig In vitro study 

intramuscular 18 mg/kg 

CBA/J mice/ Single injection, 

Nickel sulfate B6C3F, mice Up to 4.000 mg/kg/day 

(female)/oral for 23 weeks 

Nickel subsulfide Cynomolgus monkey Intratracheal 

0.06 pmol/g lung 

instillation 

Humoral Immunity 

intramuscular 18 mg/kg 

Nickel chloride CBA/J mice/ Single injection, 

C57BL/6J mouse In vitro exposure 

spleen cells to nickel chloride 

Inhibited macrophage migration Hennighausen and 

proliferation 

Reduced T-lymphocyte 

( 1984) 

Smialowicz et al. 

Lange (1980) 

Listeria challenge) 

in spleen cells; resistance to 

activity; PFC assay; mitogen response 

response to LPS (no effect on NK 

Depressed spleen lymphoproliferative Dieter et al. (1988) 

cells (in lung) 

No effect on antibody-forming Haley et al. (1987) 

Reduced antibody response to T-cell Smialowicz et al. 

dependent sheep red blood cells (1984) 

Decreased response Lawrence (1981) 

(continued) 
Introduction 21 

Nickel Compound SpeciedRoute Treatment 

Studies on the Immunologic Effects of Nickel Compounds (continued) 

TABLE 2 

Response Reference 

Nickel chloride (continued) Swiss albino mice/ 

Humoral Immunity (continued) 

intramuscular 

sheep red blood cells 

immunization with 

weight followed by 

3-12 pg Ni/kg body 

exposure at 250 pg/m’ 

2-hour inhalation 

Depressed antibody formation Graham et al. (1975a) 

inhalation 

Swiss mice/ 

to sheep red blood cells 

Depressed antibody response Graham et al. (1978) 

1 

Nickel acetate 

ratshtraperitoneal 

Sprague-Dawley 

bacteriophage 

immunized with E. coli 

11 mg/kg body weight 

antibody response 

Depressed circulating 

(1975) 

Figoni and Treagan 

Nickel oxide 

inhalation 

Wistar rats/ 

4 weeks to 4 months 

25-800 pglm’ for 

antibodies to sheep red blood cells 

Decreased ability to form spleen 

( 1984) 

Spiegelberg et al. 

Nickel chloride 

Macrophage Function 

intramuscular 

CBA/J mice/ 

18 mglkg 

Single injection, 

of peritoneal macrophages 

No effect on phagocytic capacity 

( 1984) 

Smialowicz et al. 

Rabbits 

in vitro exposure 

Alveolar macrophage Reduced viability of macrophages Graham el al. (1975b) 

nickel chloride 

Nickel oxide and 

inhalation 

Wistar rats/ 

2 weeks at 0.1 mg/m3 

6 daydweek for 

12 hours/day, 

800 pglm’ for 2 weeks 

no change after nickel chloride 

macrophages after nickel oxide; 

Increased number of alveolar 

phagocytic ability 

Decrease in alveolar macrophage 

Bingham et al. (1972) 

Nickel oxide 

inhalation 

Wistar rats/ 

( 1984) 

Spiegelberg et al. 

Nickel subsulfide 

monkey 

Cynomolgus 

0.06 pmol/g lung 

instillation 

Intratracheal Lung macrophage activity decreased Haley et al. (1987) 

Natural Killer Cell Activity 

Nickel chloride 

intramuscular 

C57BL/6J mice/ 

CBA/J and 

18 mg/kg 

Single injection, 

Yac-1 murine lymphoma cells) 

Depressed NK activity (against 

(1984, 1985, 1986) 

Smialowicz et al. 

Host Resistance 

inhalation 

nickel oxide Sprague-Dawley rats/ 

Nickel chloride and CD mice and 0.5 mg/m3 for 2 hours Enhanced respiratory infection to Adkins et al. (1979) 

Streptococcus 
22 Nickel Sulfate Hexahydrate, NTP TR 454 

peritoneal macrophages. 

nickel compounds affected the phagocytic activity of 

1.8 mg nickel/m3 nickel subsulfide. None of the 

macrophage phagocytic activity, as did 0.45 or 

of nickel oxide resulted in low levels of alveolar 

low mixed lymphocyte response. All concentrations 

exposed to 1.8 mg nickel/m3 nickel subsulfide had a 

1.8 mg nickel/m3 nickel subsulfide. Only mice 

exposed to nickel oxide and in mice exposed to 

forming cells were observed in spleens of mice 

those in the controls. Low numbers of antibody1.8 mg nickel/m3 nickel subsulfide were greater than 

2.0 and 7.9 mg nickel/m3 nickel oxide and 

in lung-associated lymph nodes of mice exposed to 

nickel subsulfide. Numbers of antibody-forming cells 

and nickel oxide and to 0.45 or 1.8 mg nickel/m3 

highest concentrations of nickel sulfate hexahydrate 

lavage samples was increased in mice exposed to the 

compounds. The number of alveolar macrophages in 

nodes were increased in size after exposure to all 

than those of the controls. Lung-associated lymph 

1.8 mg nickel/m3 of nickel subsulfide were lower 

hexahydrate. Thymic weights in mice exposed to 

0.027,O. 11, and 0.45 mg nickel/m3 for nickel sulfate 

0.47,2.0, and 7.9 mg nickel/m3 for nickel oxide; and 

0.45, and 1.8 mg nickel/m3 for nickel subsulfide; 

for 13 weeks. Exposure concentrations were 0.11, 

hexahydrate for 6 hours per day and 5 days per week 

nickel subsulfide, nickel oxide, or nickel sulfate 

sured in B6C3Fl mice after inhalation exposure to 

Toxic responses to the immune system were meatrations (Haley et al., 1990). 

observed at occupationally relevant exposure concenof the nickel compound, and these effects were 

system, depending on dose and physicochemical form 

nickel can have varying effects on the immune 

Results indicate that inhalation exposure of mice to 

depressed natural killer cell activity in the spleen. 

Only 1.8 mg nickel/m3 nickel subsulfide caused a 

row and spleen of B6C3Fl mice (Dieter et al., 1988). 

a depressed proliferating response in the bone marto deliver 116 to 396 mg/kg body weight) resulted in 

for 180 days (1 to 10 g/L drinking water, estimated 

Administration of nickel sulfate in the drinking water 

and the carcinogenic effects of nickel. 

relationship between effects on the immune system 

Further, there are no studies to examine if there is a 

not been determined (Nicklin and Nielsen, 1992). 

clinical significance of these studies in humans has 

potential of nickel to affect the immune system, the 

While xperimental studies in animals show the 

the exposed workers. 

inflammatory or fibrogenic responses in the lungs of 

sinter workers and found no evidence of significant 

Muir et al. (1993) reviewed X-rays of 745 former 

the sole causative agent of toxicity (ATSDR, 1992). 

not always been possible to conclude that nickel is 

other toxic metals and/or cigarette smoke, and it has 

industrial setting, these workers are often exposed to 

observed in workers exposed to nickel in the 

(WHO, 1991). While respiratory toxicity has been 

pulmonary fibrosis in workers inhaling nickel dust 

are rare (Nemery, 1990). There were also reports of 

Hypersensitive allergic asthmatic reactions to nickel 

sinusitis, and nasal-septal perforations. 

sures were occasionally associated with rhinitis, 

ratory system. In the industrial setting, nickel exporefineries where the primary toxicity is to the respicompounds came from studies of workers in nickel 

Most of the toxicity information on nickel and nickel 

Humans 

diseases has not been observed (Doll et al., 1990). 

from non-malignant respiratory effects or other 

between nickel exposure and cancer, excess mortality 

epidemiologic studies that have shown an association 

nickel-contaminated water (ATSDR, 1992), In 

reticulocytes, or muscular pain in workers exposed to 

gastrointestinal effects, transient increases in blood 

vascular effects in a child ingesting nickel sulfate and 

well characterized. These reactions included cardioisolated cases where exposures to nickel were not 

reactions to nickel were reported in humans in 

of nickel toxicity (ATSDR, 1992). Other toxic 

containing jewelry and/or prosthesis is another form 

general population, contact sensitivity to nickelgeneral population and in exposed workers. In the 

Nickel contact hypersensitivity has been seen in the 
Introduction 23 

CARCINOGENICITY 

1971). 

carcinogenic effects of nickel (Furst and Schlauder, 

hamster may be less sensitive than the rat to the 

incidence of lung tumors (Wehner et al., 1975). The 

2.2) for 2 years did not have an increase in the 

diameter of 0.3 pm; geometric standard deviation of 

Hamsters exposed to 53 mg nickel oxide/m3 (median 

Donnelly , 1965). 

exposed to nickel carbonyl (Sunderman and 

showed a low incidence of lung tumors in rats 

3 timedweek for 1 year). Follow-up studies also 

nickel.carbony1 (0.03 to 0.25 mg/m3 for 30 minutes 

lung tumors in groups of Wistar rats exposed to 

Sunderman et al. (1959) found a low incidence of 

Table 3. 

nogenic potential of nickel compounds is presented in 

and tabulation of over 100 experiments on the carciinjection site. A portion of the IARC (1990) listing 

been associated with a carcinogenic response at the 

nickel salts such as nickel sulfate have generally not 

neoplasms at he injection site, while the soluble 

subsulfide, nickel carbonyl, and nickel powder cause 

intramuscular injection). Nickel oxide, nickel 

pounds after local injection (e.g., subcutaneous or 

studies on the carcinogenic potential of nickel com- 

(IARC, 1990) summarized the results of experimental 

The International Agency for Research on Cancer 

Experimental Animals 

compared with a survival of 3 1 % in control groups. 

than 5 % of the animals in exposed groups were alive 

At the end of the 108-week exposure period, fewer 

compared to less than 0.5 % of 2 15 control animals. 

12 % to 14 % of the 208 animals had lung tumors 

5 daydweek for 108 weeks). In the exposed groups, 

exposed to 1 mg/m3 by inhalation (6 hourdday and 

increased incidence in lung tumors in F344/N rats 

particles were between 1 and 1.5 pm) caused an 

particles were smaller than 1 pm in diameter; 25 % of 

et al. (1975) reported that nickel subsulfide (70% of 

hydrate by inhalation exposure is limited. Ottolenghi 

oxide, nickel subsulfide, and nickel sulfate hexaInformation on the carcinogenic potential of nickel 

dence of toxic lesions). 

the 1 mg/kg group (generally with only a low inciplastic change) versus a 10% carcinoma incidence in 

nomas (there was a high incidence of tracheal hyper- 

(3 mg/kg) caused only a 1.5 % incidence of carcibased on the finding that the more toxic dose 

resulting in a misleadingly low carcinoma incidence, 

that toxicity might decrease a carcinogenic response 

transplants in female F344 rats. These authors noted 

subsulfide/kg caused tumors in heterotrophic tracheal 

a single intratracheal dose of 1 or 3 mg nickel 

mucosa. Yarita and Nettesheim (1978) reported that 

potential of nickel subsulfide for the respiratory tract 

Other experimental studies indicated carcinogenic 

no treatment-related lesions were observed. 

or dogs (0, 100, 1,000, 2,500 ppm) for 2 years, and 

nickel sulfate hexahydrate in the diet of Wistar rats 

not reached. Ambrose et al. (1976) administered 

Mitchener, 1975); the maximum tolerated dose was 

mice (Schroeder et al., 1964; Schroeder and 

trations (5 ppm) induced no lung lesions in Swiss 

Lifetime exposure to nickel acetate at low concenafter oral administration is limited (IARC, 1990). 

Information on the carcinogenic potential of nickel 

(IARC, 1987). 

to different concentrations of nickel compound(s) 

compounds or the risk for cancer based on exposure 

to evaluate the carcinogenic risk for individual nickel 

although there was insufficient information available 

nickel compounds as human carcinogens (Group l), 

nickel refinery workers, IARC classified nickel and 

on the finding of lung and/or nasal sinus tumors in 

(IARC, 1976, 1987, 1990; Doll et al., 1990). Based 

ated with an increase in lung and nasal sinus tumors 

Exposure to nickel in the workplace has been associHumans 

world (Doll, 1984). 

or other nickel industrial operations throughout the 

from other studies of nickel refineries, nickel mines 

Company (INCO) refineries in Ontario, Canada; or 

Kristiansand, Norway; the International Nickel 

in nickel refineries inClydach, South Wales; 

to nickel came from studies on occupational exposure 

Information on the hazards associated with exposure 
24 Nickel Sulfate Hexahydrate, NTP TR 454 

in Experimental Animalsa 

Summary of Studies Used to Evaluate the Carcinogenicity of Nickel Compounds 

TABLE 3 

Nickel Compound SpecieslRoute Lesion Incidenceb Reference 

Nickel oxides and hydroxides 

Rathnhalation 

Nickel monoxide Rathhalation 

Rat/intrapleural 

Rathntratracheal 

Rathntraperitoneal 

Rathtraperitoneal 

Rathbperiosteal 

Rathntramuscular 

Rat/intramuscular 

Rathtramuscular 

Rathntramuscular 

Rat/intramuscular 

Nickel monoxide 

(green) 

Nickel monoxide 

Nickel hydroxide 

Nickel trioxide 

(continued) 

Radintrarenal 

Hamsterlintratracheal 

Hamstedinhalation 

Mouselintramuscular 

Rathtrarnuscular 

Rat/intramuscular 

Rat/intramuscular 

Rathtracerebral 

31/32 local lesions 

Controls: 0/32 local lesions 

0.2 mg/m’: 0120 lesion 

0.06 mg/m3: 0140 lesion 

8 mg/m3: 1/8 lung lesion 

0.6 mg/m3: 016 lung lesion 

10 x 15 mg: 12/38 lung lesions 

10 x 5 mg: 10/37 lung lesions 

Controls: 0140 lesions 

25 mg: 12/34 local lesions 

46/47 local lesions 

0/20 local lesions 

0120 local lesions 

14/15 local lesions 

0/20 local lesions 

2/20 local lesions 

21/32 local lesions 

0/12 local lesions 

100 mg: 15/36 local lesions 

Controls: 4/50 lung lesions 

1/51 osteosarcoma 

33/50 and 23/52 local lesions 

Dried gel: 5/19 local lesions 

15/20 local lesions 

1/49 lung lesions 

Crystalline: 3/20 local lesions 

3/20 local lesions 

0110 local lesions 

Colloidal: 0/13 local lesions 

Horie e? al. (1985) 

Glaser et al. (1986) 

Skaug et al. (1985) 

Pott et al. (1987) 

Pott et al. (1989, 1992) 

Pott et al. (1987) 

Beny er al. (1984) 

Berry et al. (1984) 

Sunderman and McCully (1983) 

Sosidski (1975) 

Gilman (1966) 

Gilman (1962) 

Sunderman et al. (1 984) 

Farrell and Davis (1974) 

Wehner et al. (1975, 1979) 

Gilman (1962) 

Kasprzak et al. (1983) 

Gilman (1 966) 

Sosidski (1975) 

Judde er al. (1987) 
Introduction 25 

in Experimental Animals (continued) 

Summary of Studies Used to Evaluate the Carcinogenicity of Nickel Compounds 

TABLE 3

Nickel Compound SpecieslRoute Lesion Incidence Reference 

Nickel disulfide 

Nickel sulfides 

Nickel sulfide 

Nickel sulfide 

&Nickel sulfide 

(amorphous) 

Nickel sulfide 

&Nickel sulfide 

Nickel sulfide 

(amorphous) 

(amorphous) 

Nickel subsulfide 

Rathntramuscular 

Rathntrarenal 

RaVintramuscular 

Ratlintramuscular 

Rathntramuscular 

Ratlintrarenal 

Ratlintrarenal 

Ratlintrarenal 

Ratlinhalation 

Ratlintratracheal 

Ratlsubcutaneous 

Ratlintrapleural 

Rathntramuscular 

Ratlintramuscular 

Rat/subcutaneous 

5.6 mg: 0/10 local lesions 

2/10 local lesions 

12/14 local lesions 

3/25 local lesions 

14/14 local lesions 

22.4 mg: 0/10 local lesions 

0/15 local lesions 

8/14 local lesions 

0/18 local lesions 

15/208 benign lung lesions 

14/208 malignant lung lesions 

3.75 mg: 12/40 lung lesions 

1.88 mg: 13/45 lung lesions 

0.94 mg: 7/47 lung lesions 

3.3 mg: 37/39 local lesions 

28/32 local lesions 

Controls: 

25/28 local lesions 

18/19 local lesions 

10 mg: 37/40 local lesions 

10 mg powder: 

1/19 local lesion 

14/17 local lesions 

10 mg diffusion chamber: 

19/20 local lesions 

14/17 local lesions 

500 mg discs: 

577 local lesions 

500 mg fragments: 

Sunderman and Maenza (1976) 

Sunderman et af. (1984) 

Sunderman (1984) 

Sunderman (1984) 

Sunderman (1984) 

Sunderman et af. (1 984) 

Sunderman et af. (1984) 

Jasmin and Riopelle (1976) 

Ottolenghi et af. (1975) 

Pott et af. (1987) 

Mason (1972) 

Skaug et af. (1985) 

Gilman and Herchen (1963) 

Gilman (1962) 

Shibata et af. (1989) 

(continued) 
Nickel Sulfate Hexahydrate, NTP TR 454 

in Experimental Animals (continued) 

Summary of Studies Used to Evaluate the Carcinogenicity of Nickel Compounds 

TABLE 3 

Nickel Compound SpeciedRoute Lesion Incidence Reference 

Nickel subsulfide Ratlintramuscular 

Rathntramuscular 

Ratlintramuscular 

Ratlintramuscular 

Ratlintramuscular 

Rathntramuscular 

Ragintraperitoneal 

Rat/intraperitoneal 

Rathtraperitoneal 

Rathntramuscular 

Ratlintramuscular 

Nickel subsulfide Rathntramuscular 

a-Nickel subsulfide Ratlintramuscular 

Nickel subsulfide 

Nickel sulfides (continued) 

Ratlintramuscular 

Removal of disc after 206 days: 

Removal of disc after 128 days: 

Removal of disc after 64 days: 

(disc) 

10110 local lesions 

7/10 local lesions 

4/10 local lesions 

Hooded: 11/20 local lesions 

Fischer: 59/63 local lesions 

20 mg: 9/9 local lesions 

5 mg: 8/20 local lesions 

10 mg: 34/40 local lesions 

3.3 mg: 38/39 local lesions 

Hooded: 14/23 local lesions 

NM black: 28/28 local lesions 

5 mg: 29/30 local lesions 

2.5 mg: 28/30 local lesions 

1.2 mg: 23/30 local lesions 

0.6 mg: 7/30 local lesions 

0.63 mg: 7/29 local lesions 

6 mg: 20/36 local lesions 

27/42 local lesions 

9/37 local lesions 

19/20 local lesions 

2/100 local lesions 

10/20 local lesions 

9/9 local lesions 

20 mg: 9/9 local lesions 

12 mg: 25/35 local, lesions 

In glycerin: 7/16 local lesions 

10/20 local lesions 

0120 local lesions 

25 mg: 25/34 local lesions 

In saline: 11/24 local lesions 

Ratlintrarenal 

Radintrafemoral 

Ratlsubperiosteal 

Herchen and Gilman (1964) 

Daniel (1966) 

Mason (1972) 

Sunderman and Maenza (1976) 

Yamashiro er al. (1980) 

Sunderman et al. (1976) 

Sunderman (1981) 

Pott et al. (1989, 1992) 

Pott et al. (1987) 

Gilman (1966) 

Shibata et al. (1989) 

Judde et al. (1987) 

Berry et al. (1984) 

Sunderman (1984) 

Jasmin and Riopelle (1976) 

Berry et al. (1984) 

Berry et al. (1984) 
Introduction 27 

in Experimental Animals (continued) 

Summary of Studies Used to Evaluate the Carcinogenicity of Nickel Compounds 

TABLE 3 

Nickel Compound SpecieslRoute Lesion Incidence Reference 

Nickel sulfides (continued) 

cy-Nickel subsulfide Rathntrarenal 

Nickel subsulfide 

Nickel subsulfide 

cy-Nickel subsulfide 

cy-Nickel subsulfide 

(continued) 

Nickel subsulfide 

Rathntraocular 

Rathntratesticular 

Rat/uansplacental 

tracheal grafts 

into subcutaneous implanted 

Rat/pellet implantation 

Mouselintratracheal 

Ravintra-fat 

Radintra-articular 

Mouselsubcutaneous 

Mousdintramuscular 

Mousdintramuscular 

Mouse/intramuscular 

Hamster/intramuscular 

Hamsterlintratracheal 

Hamstedtopical 

Rabbithtramuscular 

Long-Evans: 0112 local lesions 

Fischer 344: 9/32 local lesions 

NIH black: 6/12 local lesions 

Wistar Lewis: 7/11 local lesions Sunderman et al. (1979) 

14/15 local lesions 

16/19 local lesions 

No difference in lesion 

incidence 

15 mg: 45/64 local lesions 

5 mg: 9/60 local lesions 

No increase in lung 

9/20 local lesions 

16/19 local lesions 

lesion incidence 

C57B16: 5/10 local lesions 

10 mg: 4/8 local lesions 

5 mg: 4/8 local lesions 

C3H: 9/18 local lesions 

Swiss: 27/45 local lesions 

10 mg: 7/8 local lesions 

5 mg: 4/8 local lesions 

Controls: 0/14 local lesions 

0/62 lung lesions 

DBAIZ: 6/10 local lesions 

10 mg: 12/17 local lesions 

5 mg: 4/15 local lesions 

1,080 mg total: 0/13 local lesions 

540 mg total: 0/15 local lesions 

108 mg total: 0/7 local lesions 

54 mg total: 0/6 local lesions Sunderman (1983a) 

16 local lesions Hildebrand and Biserte (1979a,b) 

Damjanov ef al. (1978) 

Sunderman (1983a) 

Albert et al. (1980); 

Sunderman et al. (1981) 

Yarita and Nettesheim (1978) 

Fisher et al. (1986) 

Shibata et al. (1989) 

Shibata ef al. (1989) 

Oskarsson et al. (1979) 

Gilman (1962) 

Oskarsson et al. (1979) 

Sunderman (1983a) 

Sunderman (1983b) 

Muhle et al. (1992) 
Nickel Sulfate Hexahydrate, NTP TR 454 

in Experimental Animals (continued) 

Summary of Studies Used to Evaluate the Carcinogenicity of Nickel Compounds 

TABLE 3

Nickel Compound Species/Route Lesion Incidence Reference 

Nickel ferrosulfide Rat/intramuscular 

Nickel subsulfide Salamander/intraocular 

a-Nickel subsulfide Rabbithntramuscular 

Nickel sulfides (continued) 

Rat/intrarenal 

Nickel salts 

Basic nickel carbonate Rat/intraperitoneal 

tetrahydrate 

Nickel acetate Mouse/intraperitoneaI 

tetrahydrate 

Nickel acetate 

Nickel ammonium 

sulfate 

Nickel carbonate 

Nickel chloride 

hexahydrate 

Nickel chloride 

Nickel chromate 

Nickel fluoride 

Nickel sulfate 

Mouse/intraperitoneaI 

Rathntramuscular 

Rathntraperitoneal 

Rathntramuscular 

Rathntraperitoneal 

Rathtramuscular 

Rathntrarnuscular 

Rat/intrarnuscular 

Rathntramuscular 

Rathntramuscular 

Rathtramuscular 

Rathntramuscular 

15/15 local lesions 

7/8 local lesions 

014 local lesions 

1/12 local lesions 

50 mg: 3/33 lung lesions 

25 mg: 1/35 lung lesions 

Controls: 1/33 lung lesions 

360 mg: 12/19 lung lesions 

180 mg: 7/14 lung lesions 

72 mg: 8/18 lung lesions 

1/35 local lesions 

1 .S lung lesions/animal 

Controls: 0.32 lung 

lesions/animal 

50 mg: 5/31 lung lesions 

25 mg: 3/35 lung lesions 

Controls: 1/33 lung lesions 

0/35 local lesions 

6/35 local lesions 

0/35 local lesions 

4/32 lung lesions 

Controls: 1/33 lung lesions 

1/16 local lesions 

0120 local lesions 

1/35 local lesions 

3/18 local lesions 

OD0 local lesions 

Sunderman et al. (1984) 

Sunderman (1984) 

Okamoto (1987) 

Sunderman (1983b) 

Pott et al. (1989, 1992) 

Stoner et al. (1976) , 

Poirier et al. (1984) 

Payne ( 1964) 

Pott et af. (1989, 1992) 

Payne (1964) 

Pott et al. (1989, 1992) 

Payne (1964) 

Payne (1964) 

Kasprzak et al. (1 983) 

Gilman (1966) 

Payne ( 1964) 

Gilman (1966) 

Sunderman (1984) 

(continued) 
Introduction 29 

in Experimental Animals (continued) 

Summary of Studies Used to Evaluate the Carcinogenicity of Nickel Compounds 

TABLE 3 

Nickel Compound SpecieslRoute Lesion Incidence Reference 

Nickel salts (continued) 

hexahydrate 

Nickel sulfate Ratfintramuscular 0132 local lesions Gilman (1962) 

heptahydrate 

Nickel sulfate Rathntraperitoneal 

6/30 lung lesions 

Controls: 1/33 lung lesions Pott et ai. (1989, 1992) 

Other 

Nickel carbonyl Rathhalation 

1/32 pulmonary lesions 

60 mglm' for 32 weeks: 

1/64 pulmonary lesions 

30 rnglm' for 32 weeks: 

1/80 pulmonary lesion 

250 mg/m' once: 

Sunderman et ai. (1957, 1959) 

Ratfinhalation 

1/71 lung lesions 

Controls: 0132 lung lesions Sunderman and Donnelly (1965) 

Ratfintravenous 19/120 lung lesions Lau et ai. (1972) 

a From IARC (1990) 

Number of animals with lesion per effective number 

related cancers. 

and many of the workers studied did not have nickelprimarily on ''high-risk'' cohorts of nickel workers, 

ments of total airborne nickel. This study focused 

procedures used and a few relatively recent measuretered based on knowledge of the nickel process 

also estimate the type of nickel exposures encounTempleton, 1994; Norseth, 1994). Doll et al. (1990) 

1994; McIlveen and Negusante, 1994; Nieboer and 

(1990) and in other more recent summaries (Courtin, 

throughout the world can be found in Doll et al. 

operations in 10 different mines or refineries 

mined and the calcining, smelting, and refining 

operations. A complete analysis on the type of ore 

cancer after exposure to nickel in mining or refinery 

1990) reviewed the epidemiological evidence for 

Nickel Carcinogenesis in Man (Doll et al., 

(USEPA, 1986) and the International Committee on 

The United States Environmental Protection Agency 

(Doll et al., 1990). 

converted impure nickel-copper matte to an oxide 

roasting, sintering, and calcining processes that 

was particularly noted in refinery work involving 

An increased risk for lung and nasal sinus cancers 

exposure to nickel (USEPA, 1986; Doll et al., 1990). 

ments were made in factory design that reduced 

respirators and masks was introduced, and improveused to extract copper was reduced, the use of 

reduced, the arsenic contamination in sulfuric acid 

1925, the copper and sulfate content of the matte was 

in workers who were employed prior to 1925. After 

1933, nasal sinus and lung cancers were first noted 

opened in 1902 and used a nickel-copper matte. In 

Clydach Nickel Refinery (Mond Nickel Works) 

(Bridge, 1933; Doll, 1958; Morgan, 1958). The 

from refinery workers at Clydach, South Wales 

rise to lung and nasal sinus cancers was obtained 

The first indication that some form of nickel can give 
30 

concentrations were highest. 

workers in the reduction area where nickel carbonyl 

furnace areas. There was no increased risk to 

those workers employed in the copper sulfate and 

plant and found the highest incidence of cancer in 

nasal sinus cancers found in workers in the Clydach 

Pet0 et al. (1984) analyzed the incidence of lung and 

1990). 

cancer risk, but no nasal sinus cancers (Doll et al., 

mining operations in Ontario had an increase in lung 

is primarily petlandite (NiFeS,). Men working in 

and the Port Colborne refinery) that use an ore that 

include the Sudbury area mines (Copper Cliff Smelter 

1989a,b; Muir et al., 1994). Facilities operated 

Canada) mines and refineries (Roberts et al., 

from studies of workers in the INCO (Ontario, 

Other evidence for nasal sinus and lung cancer come 

1978). 

and urine nickel concentrations (Hsgetveit et al., 

electrolysis workers had the highest average plasma 

cancer (USEPA, 1986; Doll et al., 1990). The 

ing the soluble forms of nickel as the cause for the 

working in the electrolysis department, thus implicatsinus and lung cancer risks were increased in men 

sulfate and nickel chloride. In this cohort, nasal 

Electrolysis workers are also exposed to nickel 

dust containing nickel subsulfide and nickel oxide. 

roasting and smelting operations are exposed to dry 

an electrolysis process to refine the ore. Workers in 

receives nickel-copper matte from Canada and uses 

The Falconbridge refinery in Kristiansand, Norway, 

more than a year (Doll et al., 1990). 

men exposed to sulfidic nickel at 4 mg nickel/m3 for 

evidence for an increased incidence in lung cancer in 

although the data from this cohort provided weak 

increased incidence in lung cancer in this population, 

Committee reported no clear evidence for an 

and/or nickel matte from New Caledonia. The Doll 

which received nickel-copper matte from Canada 

workers at a refinery in Huntington, West Virginia, 

Enterline and Marsh (1982) studied cancer rates in 

ef al. , 1994). Nickel at this site is mined from nickel 

lung or upper respiratory tract cancers (Goldberg 

New Caledonia showed no increased.' incidence of 

nickel mining, smelting, and refinery operations in 

Results of epidemiology studies of workers in the 

Nickel Sulfate Hexahydrate, NTP TR 454 

1990). 

cancer in this group of nickel workers (Doll et al., 

increased incidence in lung or upper respiratory tract 

Doll Committee also reported little evidence for an 

laterites including silicate and limonite ores. The 

Co., England (Doll ef al., 1990). 

nickel refinery, Finland; and Henry Wiggin Alloy 

Gaseous Diffusion Plant, Tennessee; Outokumpu Oy 

the Hanna Nickel Smelting Co., Oregon; Oak Ridge 

West Virginia; and New Caledonia mines) as well as 

refinery, Kristiansand, Norway; Huntington Alloys, 

and Coniston], Ontario, Canada; Falconbridge 

mines and refineries [Copper Cliff, Port Colborne, 

Falconbridge Nickel Mines, Ontario, Canada; INCO 

(nickel refinery operations, Clydach, South Wales; 

Committee include the six cohorts mentioned above 

The ten cohorts of nickel workers studied by the Doll 

forms at concentrations greater than 10 mg nickel/m3. 

of 1 mg nickel/m3 and to exposure .to less soluble 

soluble nickel compounds at concentrations in excess 

cohorts are primarily related to exposure to watersuggests that respiratory cancer risks in ''high-risk'' 

species. However, the evidence from these studies 

specific estimates of risks for individual nickel 

investigators were not able to provide exposurecancers elsewhere than in the lung or nose. These 

or any of its compounds was likely to produce 

evidence to suggest that exposure to metallic nickel 

lung and nasal sinus cancer risks. There was no 

that metallic nickel was associated with increased 

less soluble forms of nickel. There was no evidence 

that it may enhance risks associated with exposure to 

increased the risk of lung and nasal sinus cancer and 

was evidence that exposure to soluble nickel salts 

increased lung and nasal sinus cancer risks. There 

trations of oxidic nickel was also associated with 

absence of sulfidic nickel, exposure to large concena mixture of oxidic and sulfidic nickel. In the 

respiratory cancer risk was attributed to exposure to 

rise to lung and nasal sinus cancer. Much of the 

suggested that more than one form of nickel gives 

the overall conclusion by the Doll Committee 

The results within the individual cohorts varied, but 

sure to nickel (ATSDR, 1992). 

genic effect in humans specifically after oral expoThere are no studies evaluating the potential carcino- 
Introduction 31 

et al., 1991). 

marker of oxidatively damaged DNA (Littlefield 

8-hydroxy-2' -deoxyguanosine (8-OH-dG), a bioin vitro studies, nickel ions induce increases in 

radicals (Tkeshelashvili et al., 1993); and 3) in 

by either ultraviolet irradiation or oxygen free 

CC 4 TT mutations consistent with damage to DNA 

bacterial DNA, nickel ions produce tandem double 

et al., 1993); 2) in forward mutation assays with 

nickel (11)-thiol complexes and molecular oxygen (Shi 

radicals, suggesting free radicals. are generated by 

generates hydroxyl radicals and carbon-centered alkyl 

of nickel ions with cysteine under aerobic conditions 

damage and cancer. Studies show that 1) incubation 

and the subsequent oxidative reactions lead to DNA 

studies suggest that nickel generates free radicals, 

intracellular oxidants (Costa et al., 1994). Recent 

proteins and/or the ability of nickel to generate 

ability of nickel ions to interact with chromatin 

cancer by nickel compounds may be related to the 

1992). The mechanisms involved in the induction of 

understood (Sunderman, 1989; Costa, 1991; Snow, 

mechanism for this carcinogenic activity is not fully 

the IARC as Group 1 (human) carcinogens, the 

While nickel and nickel compounds are classified by 

water-soluble nickel salts (Costa e? al., 1994). 

than would be achieved by the cellular uptake of 

ions and results in a higher concentration of nickel 

whose acidity accelerates the dissolution of nickel 

cytized nickel particles are internalized in vacuoles 

passively diffuse through the cell membrane. Phagocytized than are the water-soluble nickel salts, which 

insoluble nickel compounds are more readily phagofindings may be related to the fact that waterpounds are the most potent carcinpgens. These 

nickel compounds, the water-insoluble nickel comAfter subcutaneous or intramuscular injection of 

tial to cause embryotoxicity in rodents. In these 

istered orally or by peritoneal routes have the potenshow that water-soluble nickel compounds adminLeonard and Jacquet (1984) reviewed studies which 

Experimental Animals 

AND DEVELOPMENTAL TOXICITY 

REPRODUCTIVE 

posed to in drinking water or in the diet. 

istered at higher doses than humans would be exstudies, the nickel compounds were generally adminUnited States (48 pg/L water) (NAS, 1975). 

tration of nickel found in drinking water in the 

these studies are higher than the average concenof the pups (Dostal et af., 1989). The doses used in 

was excreted in the milk and was found in the plasma 

body weight or 23 mg/kg) to lactating rats, nickel 

subcutaneous dose (10 to 100 pmol NiC1,. 6H,O/kg 

nickel chloride hexahydrate was given as a single 

autoradiography (Olsen and Jonsen, 1979). When 

observed in the embryo as measured by whole-body 

placenta, nd a marked uptake of nickel was 

pregnant mice, nickel was found to cross the 

[63Ni]-labeled nickel chloride was injected into 

brain, and heart. In another experiment, when 

various fetal tissues including liver, kidney, lung, 

weight) to pregnant mice, the label was detected in 

oral .bolus dose ( 10 pmol or 0.58 mg/kg body 

[63Ni]-labeled nickel chloride was administered as an 

excreted in the milk of lactating animals. When 

nickel compounds can cross the placenta or be 

Studies in rodents have 'indicated that water-soluble 

1993). 

the proportion of dead pups per litter (Smith et al., 

gestation and lactation periods caused an increase in 

prior to mating and then during two successive 

of nickel compound) to female rats for 11 weeks 

(50 and 250 ppm, estimated to deliver 7 or 3 1 mg/kg 

Nickel chloride administered in the drinking water 

plasma glucose concentration (Mas et al., 1985). 

At these doses, there was an increase in maternal 

lus, hydronephrosis, heart defects, and hemorrhage. 

skeletal retardation (poor ossification), hydrocephaPorton rats on day 8, 12, or 16 of pregnancy caused 

(1, 2, or 4 mg/kg body weight) to pregnant Wistar 

death. Nickel chloride injected intraperitoneally 

gestation also showed developmental toxicity or fetal 

by intramuscular or intraperitoneal injection during 

Other studies in rodents administered nickel chloride 
32 Nickel Sulfate Hexahydrate, NTP TR 454 

day 8 (Gilani and Marano, 1980). 

phthalmia, and reduced body size when examined at 

abnormalities in the limb development, microembryo including exencephaly, everted viscera, 

and 4 after fertilization caused malformations in the 

doses of 0.02 to 0.8 mg per egg on days 0, 1, 2, 3, 

1978). Nickel chloride injected into chicken eggs at 

fetal body weights on day 20 (Sunderman et al., 

mean number of live pups per dam and diminished 

on day 8 of gestation to Fischer rats reduced the 

Nickel chloride injected intramuscularly (16 mg/kg) 

lungs, and hydronephrosis (Sunderman et aI., 1983). 

ities including anophthalmia, microphthalmia, cystic 

live pups, and increased incidences of fetal abnormalincrease in fetal mortality, diminished body weight of 

tion (1 1 mg/kg) on day 7 of gestation caused an 

administered to pregnant dams by intravenous injecgroups (Sunderman et af., 1980). Nickel carbonyl 

neonatal mortality was increased in the xposed 

ments where dams were allowed to deliver the pups, 

palate, and fused ribs. In another series of experiobserved included cystic lung, exencephaly , cleft 

evaluated on day 15 of gestation. Teratogenic effects 

day 4, 5, 6, 7, or 8 of gestation; dams were 

carbonyl by inhalation (0.06 mg/L for 15 minutes) on 

Groups of pregnant hamsters were exposed to nickel 

toxicity (Weischer et al., 1980). 

1 through 20. There was no evidence of embryoto 1.6 mg nickel/m3 by inhalation on gestation days 

In a study of nickel oxide, Wistar rats were*exposed 

Jacquet, 1984). 

stand the mechanisms for these effects (Leonard and 

maternal toxicity. Further work is needed to undermammalian embryo, or indirect effects through 

mutagenic properties of nickel, direct effects on the 

nickel may be related to several factors including the 

barrier and enter the fetus. The embryotoxicity of 

in rodents. The metal can cross the feto-maternal 

nickel salts have the potential to cause embryotoxicity 

These and other studies how that water-soluble 

water-soluble nickel salts in electrolysis departments 

refinery workers in Russia who were exposed to 

(ATSDR, 1992). A preliminary study of nickel 

ductive effects in humans after exposure to nickel 

Until recently, there have been few studies of reproHumans 

female workers (Chashschin et af., 1994). 

noted an increased risk of pregnancy complications in 

GENETIC TOXICITY 

are dissolved by lysosomes, releasing nickel (11) ions 

nucleus (Bryan, 1981 ; Evans et al., 1982) where they 

compounds, once inside the cell, aggregate near the 

phagocytosis of nickel compounds. Insoluble nickel 

(Costa et al., 1982) are also important factors in the 

(Costa and Mollenhauer, 1980) and surface charge 

into the cell and cause genetic damage. Particle size 

the amorphous state, to be efficiently phagocytized 

compounds must be in the crystalline, rather than in 

and Heck (1983) concluded that the nickel sulfide 

transformation studies in cultured rodent cells, Costa 

tration within the cell. Based on the results of cell 

phagocytized and do not accumulate in high concenions. Soluble nickel salts cannot be efficiently 

quent higher intracellular concentration of nickel (11) 

of these compounds within the cell, and the consethrough phagocytosis (Costa, 1991), longer retention 

more efficient entry of insoluble nickels into the cell 

Presumably, this differential activity derives from the 

than the soluble or amorphous forms of nickel. 

compounds are more active in genetic toxicity assays 

1991 ; Lee et dl., 1993). Insoluble crystalline nickel 

1979; Amacher and Paillet, 1980; Morita et al., 

responses are usually weak (Nishimura and Umeda, 

ferase locus in hamster V79 cells), although these 

phoma cells and hypoxanthine phosphoribosyl transforward mutation assays (TK locus in mouse lympositive results were demonstrated in mammalian cell 

polymerases (Christie et al., 1991). In addition, 

magnesium for essential binding sites on DNA 

mammalian cells in vitro, possibly by competing with 

DNA replication and to increase replication errors in 

breaks. Nickel salts have been shown to inhibit 

es, chromosomal aberrations, and DNA strand 

malian cells in the form of sister chromatid exchangpounds that induce chromosomal damage in mamresults in in vitro assays designed to identify combacterial mutagens, but they often give positive 

Nickel compounds are not typically detected as 

Costa (1991), Snow (1992), and Costa et al. (1994). 

Coogan et al. (1989), Christie and Katisifis (1990), 

the production of these effects were presented by 

compounds and the possible mechanisms involved in 

Recent detailed reviews of the mutagenicity of nickel 
Introduction 33 

1994). 

that proceed to effect DNA damage (Costa et al., 

by the NTP are described below. 

for each of the three nickel compounds under study 

is presented in Figure 1. The genetic toxicity data 

the activities of nickel ions within mammalian cells, 

genotoxicity, based upon the current understanding of 

some of the proposed mechanisms of nickel-induced 

(Klein et al., 1991). A schematic representation of 

transformed cultured Chinese hamster cell lines 

Chinese hamster cells and to promote immortality in 

loss of a gene controlling senescence in cultured 

deletions in this region were postulated to cause the 

long arm of the X chromosome and subsequent 

1987; Costa, 1991); binding of nickel ions to the 

hamster cells (Sen and Costa, 1986a,b; Sen ef al., 

long arm of the X chromosome in cultured Chinese 

chromatic regions of the chromosomes such as the 

(Costa, 1991). Nickel binds preferentially to heterochromosomal protein rather than directly to DNA 

bly derives primarily from the binding of nickel to 

fore, the mutagenic activity of nickel (11) ions probapurified DNA (Eichorn and Shin, 1968) and thereaffinity of nickel to protein is far greater than to 

reviewed by Coogan et al. (1989). The binding 

nuclear proteins, and other nuclear structures are 

involved in the binding of nickel ions to DNA, 

Costa, 1985; Sen and Costa, 1986a). Factors 

Wetterhahn, 1982; Lee et al., 1982; Patierno and 

nickel (11)-induced DNA damage (Ciccarelli and 

crosslinks is implicated in the gneration f 

1994). The formation of persistent DNA-protein 

et al., 1992; Tkeshelashvili et al., 1993; Sugiyama, 

Kawanishi, 1989; Nieboer et al., 1989; Cotelle 

nuclear proteins (Biggart and Costa, 1986; Inoue and 

acids, glutathione, and amino acid side chains of 

the binding of nickel ions to ligands such as amino 

by hydrogen peroxide or other oxidants subsequent to 

nucleus,' produced by the oxidation of Ni+2 to Ni+3 

short-lived reactive oxygen species inside the 

mechanisms. It may- follow, the generation of 

been attributed to one or more of the following 

The DNA damage resulting from nickel exposure has 

DNA damage in repair-deficient strains of Bacillus 

nickel oxide did not result in growth inhibition due to 

in some in vitro test systems. Although exposure to 

however, there are clear indications of genotoxicity 

The mutagenicity data for nickel oxide are limited; 

tions of the metal (Popp et al., 1992). 

for example, were correlated with urine concentranoted after exposure to chromium-containing fumes, 

blood, whereas increased DNA-crosslink frequencies 

correlated with nickel concentrations in urine or 

sium. Also, the genetic effects noted were not 

well as other metals such as chromium and magneand welding fumes contain other nickel compounds as 

genetic endpoints is confounded because smelter dusts 

weak. The link between nickel oxide and these 

blood lymphocytes of workers, but the evidence is 

DNA-crosslinks (Costa et al., 1993) in peripheral 

chromosomal aberrations (Waksvik et al., 1984) and 

oxide-containing fumes or smelter dusts may induce 

epidemiology studies indicate that exposure to nickel 

testing insoluble nickel oxide. Data from human 

compounds and may not have been suitable for 

used in this test was designed for water-soluble 

Allison, 1972); however, the experimental protocol 

nickel oxide for 24, 48, or 72 hours (Paton and 

human fibroblast or leukocyte cultures exposed to 

induction of chromosomal aberrations was detected in 

for nickel oxide activity (Kargacin et al., 1993). No 

different site, the gpt gene, in V79 cells as the target 

effects were reported in mutation assays using a 

oxide (Kargacin et al., 1993). However, positive 

locus in hamster V79 cells after exposure to nickel 

embryo cells (Miura et al., 1989) or at the HPRT 

ouabain resistance locus in C3H/10Tl,, mouse 

increase in gene mutations was detected at the 

5 pg/mL nickel oxide (Costa et al., 1982). No 

in cycling Chinese hamster ovary cells incubated with 

(determined by flow cytometric analysis) was induced 

subtilis (Kanematsu et al., 1980), an S-phase block 

male Drosophila (Rodriguez-Arnaiz and Ramos, 

sex-linked recessive lethal mutations in germ cells of 

at doses of 200, 300, and 400 ppm, induced 

nickel sulfate hexahydrate, administered by injection 

tion enzymes (McGregor et al., 1988). In addition, 

1,000 pg/mL in the absence of S9 metabolic activamouse lymphoma TK+'- cells treated with 500 to 

sulfate hexahydrate did induce mutations in L5 178Y 

(Christie, 1989; Lee et al., 1993). However, nickel 

V79 cells treated with nickel sulfate hexahydrate 

increases in gpt mutants were observed in hamster 

contrast to results reported for nickel oxide) no 

typhimurium (Arlauskas et al., 1985), and (in 

mutations i Escherichia coli or Salmonella 

Nickel sulfate hexahydrate did not induce gene 
34 Nickel Sulfate Hexahydrate, NTP TR 454 

(Mathur et al., 1978). 

bone marrow cells was noted in treated animals 

body weight. Also, no change in the mitotic index of 

hydrate at doses that provided 3 or 6 mg nickel/kg 

gonial cells after injection of nickel sulfate hexations was observed in rat bone marrow or spermato1982). In vivo, no induction of chromosomal aberrawith 250 pg/mL nickel sulfate hexahydrate (Fornace, 

in human xeroderma pigmentosum fibroblasts treated 

induction of DNA single-strand breaks was detected 

nickel sulfate hexahydrate in vitro. However, no 

lymphocytes (Larramendy et al., 198 1) treated with 

Ohno et al., 1982), as well as human peripheral 

observed in hamster cells (Larramendy et al., 1981 ; 

exchanges and chromosomal aberrations was 

Ramos, 1986). Induction of sister chromatid 

production of X0 males (Rodriguez-Arnaiz and 

nickel sulfate hexahydrate (400 ppm) resulted in the 

for sex chromosome loss, only the highest dose of 

test for germ cell effects in male Drosophila, the test 

no evidence of increased lethal mutations. In another 

undergoing meiosis at the time of treatment showed 

affected; the broods obtained from sperm cells 

1986). The pre- and post-meiotic cell stages were 

sulfide resulted in an increase in the number of DNA 

ovary cells for 24 hours with 10 pg/mL nickel subet al., 1983). Treatment of cultured Chinese hamster 

in cultured Syrian hamster embryo cells (Robison 

Sonneborn et al., 1986) and unscheduled DNA repair 

in Paramecium tetraurelia without S9 (Smith- 

(Arrouijal et al., 1990). It induced lethal mutations 

results in a standard plate incorporation assay 

incubation protocol (Zeiger et al., 1992) and negative 

equivocal results in one study that used a premutation assay, crystalline nickel subsulfide gave 

mainly positive. In the Salmonella typhimurium gene 

formed with this insoluble nickel compound were 

subsulfide. However, results of in vitro tests perthird nickel compound in the present studies, nickel 

there are limited published mutagenicity data for the 

As with the two nickel compounds discussed above, 

was conducted. 

intraperitoneal injection), and no confirmatory study 

dose (250 mg/kg nickel subsulfide administered by 

This second study, however, employed only a single 

produced positive results (Arrouijal et al., 1990). 

a mouse bone marrow micronucleus test, reportedly 

(Hui and Sunderman, 1980). A second in vivo study, 

body weight) by intrarenal injection, was negative 

inhibition in rats administered 10 pg/rat (6 mg/100 g 

nickel subsulfide, a measure of DNA synthesis 

lymphocytes in vitro. One reported in vivo test with 

and micronuclei (Arrouijal et al., 1992) in human 

in chromosomal aberrations (Arrouijal et al., 1990) 

subsulfide induced significant dose-related increases 

human lymphocytes (Saxholm et al., 1981). Nickel 

1994) and sister chromatid exchanges in cultured 

cultured Chinese hamster ovary cells (Rossetto et al., 

xanthine phosphoribosyl transferase mutations in 

in the absence of S9, was a weak inducer of hypotechniques (Robison et al., 1982). Nickel subsulfide, 

strand breaks detected by alkaline sucrose gradient 

Report. 

hexahydrate studies are presented in this Technical 

nickel compounds. The results of the nickel sulfate 

toxicology and carcinogenicity information on these 

hexahydrate were performed to provide comparative 

subsulfide (NTP, 1996b), and nickel sulfate 

studies of nickel oxide (NTP, 1996a), nickel 

et al., 1975). The NTP toxicity and carcinogenicity 

which lung tumors were observed in rats (Ottolenghi 

was selected for study based on a previous study in 

the workplace in the United States. Nickel subsulfide 

selected as compounds that are commonly found in 

Nickel oxide and nickel sulfate hexahydrate were 

specific nickel compounds after inhalation exposure. 

mation on the toxic and carcinogenic properties of 

compounds for study because there was little inforThe National Cancer Institute nominated nickel 

STUDY RATIONALE 
Introduction 35 

FIGURE 1 

ef al., 1991). 

cause deletion of all or part of this region, leading to an immortalization of the cell and clonal expansion (Conway and Costa, 1989: Klein 

heterochromatic regions of the long arm of the X chromosome, which may contain a senescence gene and a tumor suppressor gene, can 

Ni+2 ions binding to heterochromatin (Lee ef al., 1982; Patierno and Costa, 1985; Sen and Costa, 1986a). 6. Binding of nickel ions to the 

(Ni” + Ni+3), releasing active oxygen species (Tkeshelashvili ef al., 1993; Sugiyama, 1994). 5. DNA-protein crosslinks are produced by 

the nuclear membrane (Costa and Heck, 1983). 4. Oxidative damage is induced in DNA by nickel ions bound to nuclear proteins 

ef al., 1982). 3. Lysosomal breakdown of insoluble nickel compounds releases large quantities of Ni+* ions which concentrate adjacent to 

et al., 1993). 2. Insoluble nickel compounds such as nickel subsulfide are phagocytized into the cell and move toward the nucleus (Costa 

1. Soluble nickel compounds such as nickel chloride diffuse into the cell; Ni+’ ions are rapidly bound to cytoplasmic proteins (P) (Lee 

Possible Mechanisms of Nickel-Induced Genotoxicity 
36 Nickel Sulfate Hexahydrate, NTP TR 454 
37 

MATERIALS AND METHODS 

PROCUREMENT 

Index, 1989). 

compound (Ostroff and Sanderson, 1959; Mer&. 

about the physical and chemical properties of the 

sulfate hexahydrate based on literature information 

chemical stability studies were performed for nickel 

mined to be greater than 98%. No accelerated 

sulfate hexahydrate. The overall purity was detertitration indicated a purity of 98.8% f 0.8 % nickel 

(470 ppm), and magnesium (120 ppm). Chelometric 

cobalt (approximately 1,500 ppm), silicon 

try indicated the major inorganic impurities were 

was the hexahydrate. Spark source mass spectrome41.3 % & 0.7 % water, confirming that the chemical 

hydrate. Karl. Fischer water analysis indicated 

with the theoretical values for nickel sulfate hexaanzlyses for nickel and hydrogen were in agreement 

spectrometry, and chelometric titration. Elemental 

Karl Fischer water analysis, spark source mass 

M062883 was determined by elemental analyses, 

violet/visible spectroscopy. The purity of lot 

nickel sulfate hexahydrate by infrared and ultrablue-green crystalline powder, was identified as 

studies are detailed in Appendix K. The chemical, a 

Sciences (NIEHS). The methods and results of these 

the National Institute of Environmental Health 

the nickel sulfate hexahydrate studies are on file at 

MO). Reports on analyses performed in support of 

laboratory, Midwest Research Institute (Kansas City, 

analyses were conducted by the analytical chemistry 

13-week, and 2-year studies. Identity and purity 

(M062883), which was used during the 16-day, 

Chemical Co. (Milwaukee, WI) in one lot 

Nickel sulfate hexahydrate was obtained from Aldrich 

OF NICKEL SULFATE HEXAHYDRATE 

AND CHARACTERIZATION 

studies and every 4 months during the 2-year studies. 

for nickel, hydrogen, and sulfur prior to and after all 

tories, Inc. (Golden, CO) using elemental analyses 

bulk chemical was performed by Huffman Laboraat room temperature. Periodic monitoring of the 

The bulk chemical was stored in amber glass bottles 

observed during the studies. 

No change in the purity of the bulk chemical was 

AEROSOL GENERATION 

the chamber. 

chamber inlet to further mix the aerosol as it entered 

Electronics, Chicago, IL) was placed below the 

A small boxer fan (model W52107FL-1002, Newark 

expose the rats and mice in these studies (Figure K4). 

Hazleton Systems, Aberdeen, MD) were used to 

whole-body exposure chambers (H1000 and H2000, 

(Tables K1 to K3). Stainless steel, multitiered, 

standard deviation ranging from 1.6 to 2.9 

and ranged from 1.8 to 3.1 pm with a geometric 

("AD) was similar for all exposure concentrations 

expressed as mass median aerodynamic diameter 

using a cacade impactor. The particle size as 

mined monthly during the 13-week and 2-year studies 

of about 40%. The aerosol particle size was deterfiltered and conditioned to achieve a relative humidity 

dilutor for uniform mixing, and the diluting air was 

hydrate aerosol. All dilutions took place in a radial 

aerosol droplets, leaving the nickel sulfate hexaair flow rate. Water then evaporated from the 

dilution air to achieve the proper concentration and 

study. The aerosol was then mixed with additional 

was required for each generator system in the 2-year 

was used for each chamber and only one nebulizer 

nebulizers, is shown in Figure K3. One generator 

a solution reservoir and manifold for up to four 

(Figure K2). The generation system, which included 

Retec nebulizer (In Tox Products, Albuquerque, NM) 

deionized water). The solution was atomized with a 

from aqueous solution (62.1 g/L in distilled and 

Nickel sulfate hexahydrate aerosol was generated 

AND EXPOSURE SYSTEM 

MONITORING 

AEROSOL CONCENTRATION 

determined gravimetrically from two 3-hour samples 

2-year study in rats, the aerosol concentrations were 

In the 13-week studies in rats and mice and the 
38 Nickel Sulfate Hexahydrate, NTP TR 454 

each filter sampling period. 

least 2 minutes at the beginning, middle, and end of 

RAM-S was used to monitor each chamber for at 

aerosol generation system during exposures. The 

concentrations and to determine the need to adjust the 

was used to monitor the stability of the aerosol 

monitor (Model RAM-S, GCA, Co., Bedford, MA) 

concentration was maintained. A continuous aerosol 

Figures K9 and K10. Good control of aerosol 

concentrations for the 2-year studies are presented in 

in Figures K7 and K8. Weekly mean exposure 

concentrations for the 13-week studies are presented 

mouse control chamber. Daily mean exposure 

chamber and 0.01 f 0.01 mg particle/m3 in the 

0.02 f 0.01 mg particle/mg3 in the rat control 

concentrations of total suspended particles were 

sample. In the 2-year studies, the mean 

of the 2-year studies by collecting one 6-hour filter 

control chambers were monitored each exposure day 

concentrations of total suspended particles in the 

each exposure chamber. The background 

three 2-hour filter samples (3 Wmin flow rate) from 

aerosol concentrations were monitored by collecting 

exposure day. In the 2-year study in mice, the 

concentration exposure chambers during each 6-hour 

samples (3 Wmin flow rate) for the igher 

exposure chambers and from three 2-hour filter 

(4.5 Wmin flow rate) for the 0.12 and 0.25 mg/m3 

CHARACTERIZATION 

CHAMBER ATMOSPHERE 

utes during the 16-day and 13-week studies and 

target (T,), determined with a RAM-S, was 12 minconcentration in the chambers to reach 90% of the 

to 9.29% for all chambers. The time for the aerosol 

2-year studies. The spatial variation ranged from 0% 

exposure, and was checked quarterly during the 

animals in the chambers during the first week of 

studies without animals in the chambers and with 

chambers was measured prior to the start of the 

formity of aerosol concentration in the exposure 

generated was nickel subsulfate hexahydrate. Unithe first week of exposure to ensure that the aerosol 

tion spectroscopy prior to exposure and once during 

for nickel content by electrothermal atomic absorpElmer TGS-2 Thermogravimetric Analysis Unit) and 

of hydration by thermogravimetric analysis (Perkin 

particle charge. The aerosol was analyzed for extent 

A Kr-85 discharger was installed in the line to reduce 

exposure time was set at 6 hours plus T,. 

8 minutes during the 2-year studies. The daily 

16-D~y STUDIES 

disease. 

evaluation and gross observation for evidence of 

rats and mice were randomly selected for parasite 

initiation of the studies, five male and five female 

7 weeks old on the first day of the studies. Before 

tined for 19 to 22 days and were approximately 

approximately 4 weeks old. Animals were quaran- 

(Frederick, MD). On receipt, the rats and mice were 

obtained from Frederick Cancer Research Facility 

Male and female F344/N rats and B6C3F, mice were 

maintenance are summarized in Table 4. 

the studies. Details of the study design and animal 

to the start of the study, on day 5, and at the end of 

for rats and mice. The animals were weighed prior 

the studies, on day 5, and at the end of the studies 

Clinical findings were recorded prior to the start of 

ad libitum. Rats and mice were housed individually. 

during exposure periods, and water was available 

16-day period. Feed was available ad libitum, except 

(excluding weekends) for 12 exposure days during a 

were xposed 6 hours and 12 minutes per day 

for 12 minutes before T, was reached; thus, animals 

12.2 mg nickel/m3). Animals were in the chambers 

60 mg/m3 (equivalent to 0, 0.7, 1.4, 3.1, 6.1, or 

tion at concentrations of 0, 3.5, 7, 15, 30, or 

were exposed to nickel sulfate hexahydrate by inhalaGroups of five male and five female rats and mice 

the analytical method were calculated on a cumulative 

spectroscopy. Limits of detection and quantitation of 

determined using electrothermal atomic absorption 

pore Co., Bedford, MA), and the nickel content was 

digestates were diluted with deionized water (Milligen peroxide and heated in a microwave oven. The 

with a mixture of nitric and sulfuric acids and hydroing the last exposure. Tissue samples were digested 

monoxide and exsanguination on the morning followconcentration, rats ,and mice were killed using carbon 

for nickel content. For determination of nickel 

kidney (rats only) from these animals were analyzed 

hydrate/m3. Samples of lung (rats and mice) and 

to 0, 3.5, 15, or 30 mg nickel sulfate hexafour or five male and female rats and mice exposed 

In addition, a tissue burden study was performed on 
Materials and Methods 39 

burden studies are found in Appendixes H and I. 

analyzed are listed in Table 4 and results of the tissue are summarized in Table 4. 

formula given by Keith et al. (1983). Tissues Details of the study design and animal maintenance 

basis for each set of samples analyzed according to a initially, weekly, and at the end of the studies. 

examined. 

groups. Table 4 lists the tissues and organs 

on target organs from rats in all other exposure 

60 mg/m3 rats, on all 0, 3.5, and 7 mg/m3 mice, and 

examinations were performed on all 0, 30, and 

and thymus were weighed. Complete histopathologic 

brain, heart, right kidney, liver, lung, right testis, 

A necropsy was performed on all rats and mice. The 

2-year studies. 

appropriate exposure concentrations to be used in the 

nickel sulfate hexahydrate and to determine the 

cumulative toxic effects of repeated exposure to 

The 13-week studies were conducted to evaluate the 

ISWEEK STUDIES 

of the NTP Sentinel Animal Program (Appendix M). 

the core or tissue burden studies using the protocols 

study and on five male and female control mice from 

five male and five female control rats from the core 

the studies, serologic analyses were performed on 

observation for evidence of disease. At the end of 

randomly selected for parasite evaluation and gross 

ies, five male and five female rats and mice were 

first day of exposure. Before initiation of the stud20 days and were approximately 7 weeks old on the 

4 weeks old. Animals were quarantined for 19 or 

On receipt, the rats and mice were approximately 

obtained from Simonsen Laboratories (Gilroy, CA). 

Male and female F344/N rats and B6C3F, mice were 

weekly for rats and mice. The animals were weighed 

were recorded prior to the start of the study and then 

and mice were housed individually. Clinical findings 

periods, and water was available ad libitum. Rats 

was available ad libitum, except during exposure 

five days per week during a 13-week period. Feed 

were exposed 6 hours and 12 minutes per day, 

12 minutes before T, was reached; thus, animals 

nickel/m3). Animals were inthe chambers for 

(equivalent to 0, 0.03, 0.06. 0.11, 0.22, or 0.44 mg 

concentrations of 0, 0.12, 0.25, 0.5, 1, or 2 mg/m3 

exposed to nickel sulfate hexahydrate by inhalation at 

Groups of 10 male and 10 female rats and mice were 

in Appendixes H and I. 

listed in Table 4, and results of the studies are found 

scribed for the 16-day studies. Tissues analyzed are 

Tissue burden methodologies used were those defrom these animals were analyzed for nickel content. 

Lung (rats and mice) and kidney (rats only) tissues 

0, 0.12, 0.5, or 2 mg nickel sulfate hexahydrate/m3. 

five or six male and female rats and mice exposed to 

In addition, a tissue burden study was performed on 

buffered saline containing 10% dimethyl sulfoxide. 

ginea and homogenizing the left testis in phosphatecount was determined by removing the tunica albuquantify spermatogenesis, testicular spermatid head 

scopically with the aid of a hemacytometer. To 

65 O C. Sperm density was then determined microbated in the saline solution and then heat fixed at 

Cauda were finely minced, and the tissue was incuepididymis was placed in buffered saline solution. 

tion of sperm motility estimates, each right cauda 

fields per slide by two observers. Following compleand nonmotile spermatozoa were counted for five 

the buffer on the slides, and the numbers of motile 

sperm effluxing from the incision were dispersed in 

at the distal border of the cauda epididymis. The 

was applied to slides and a small incision was made 

Test yolk (rats) or modified Tyrode’s buffer (mice) 

epididymal body (corpus epididymis) and weighed. 

(cauda epididymis) was then removed from the 

isolated and weighed. The tail of the epididymis 

motility. The right testis and right epididymis were 

were evaluated for sperm morphology, count, and 

proestrus, estrus, and metestrus). Male rats and mice 

used to ascertain estrous cycle stage (i.e., diestrus, 

large squamous epithelial cells were determined and 

numbers of leukocytes, nucleated epithelial cells, and 

vaginal fluid and cells were stained. Relative 

moistened with saline, if necessary, and samples of 

sacrifice, the vaginal vaults of the females were 

7 consecutive days prior to scheduled terminal 

NTP General Statement of Work (April, 1987). For 

Table 4. Methods used were those described in the 

tions. The parameters evaluated are listed in 

for sperm morphology and vaginal cytology evaluacollected from 0, 0.5, 1, and 2 mg/m3 rats and mice 

At the end of the 13-week studies, samples were 
40 Nickel Sulfate Hexahydrate, NTP TR 454 

zation are given in Appendix J. 

tive tissue evaluations and estrous cycle charactericounted with a hemacytometer. Results of reproducHomogenization-resistant spermatid nuclei were 

disc for reticulocyte quantitation. 

whole blood and new methylene blue and a Miller 

smears prepared by incubating equal volumes of 

counts were determined by light microscopy, using 

films stained with Wright-Giemsa. Reticulocyte 

mined by light microscopic examination of blood 

morphologic evaluation of blood cells were deterWestwood, MA). Leukocyte differential counts and 

ELT-8/ds hematology analyzer (Ortho Instruments, 

ogy determinations were performed on an Ortho 

parameters measured are listed in Table 4. HematolEDTA as the anticoagulant. The hematology 

minations was placed in tubes containing potassium 

by cardiac puncture. Blood for hematology detercollected for hematology from all surviving animals 

At the end of the 13-week studies, blood was 

organs and tissues examined are listed in Table 4. 

rats and mice in all other exposure groups. The 

2 mg/m3 rats and mice, and on target organs from 

logic examination was performed on all 0 and 

with hematoxylin and eosin. A complete histopathosectioned to a thickness of 5 to 6 pm, and stained 

lin, processed and trimmed, embedded in paraffin, 

fixed and preserved in 10% neutral buffered formathymus. Tissues for microscopic examination were 

heart, right kidney, liver, lung, right testis, and 

the end of the studies; organs weighed were brain, 

weights were taken from all animals that survived to 

A necropsy was performed on all animals and organ 

lung; and five males and five females from each 

evaluated at 7 months for nickel tissue burden in the 

males and seven females from each group were 

at 7 months for histopathology; as many as seven 

and five female rats from each group were evaluated 

utes) five days per week for 104 weeks. Five male 

Animals were exposed for 6 hours plus T, (8 min- 

(equivalent to 0, 0.03, 0.06, or 0.11 mg nickel/m3). 

tion at concentrations of 0, 0.12, 0.25, or 0.5 mg/m3 

were exposed to nickel sulfate hexahydrate by inhalaGroups of 63 to 65 male and 63 to 64 female rats 

Study Design 

%YEAR STUDIES 

histopathology. 

hematology, nickel tissue burden in the lung, and 

group were evaluated at 15 months for alterations in 

burden in the lung and kidney. 

group were evaluated at 15 months for nickel tissue 

thology; and five males and five females from each 

15 months for alterations in hematology and histopafive females from each group were evaluated at 

tissue burden in the lung and kidney; five males and 

each group were evaluated at 7 months for nickel 

histopathology; five males and five females from 

mice from each group were evaluated at 7 months for 

per week for 104 weeks. Five male and five female 

exposed for 6 hours plus T, (8 minutes) five days 

0.06, 0.11, or 0.22 mg nickel/m3). Animals were 

trations of 0, 0.25, 0.5, or 1 mg/m3 (equivalent to 0, 

to nickel sulfate hexahydrate by inhalation at concenGroups of 80 male and 80 female mice were exposed 

nel Animal Program (Appendix M). 

studies according to the protocols of the NTP Sentihealth of the animals was monitored during the 

6 weeks old at the beginning of the studies. The 

screening. Rats and mice were approximately 

disease. Serology samples were collected for viral 

evaluation and gross observation for evidence of 

five female rats and mice were selected for parasite 

before the beginning of the studies. Five male and 

were quarantined for 10 (rats) or 11 days (mice) 

animals were approximately 4 weeks old. Animals 

CA) for use in the 2-year studies. On receipt, 

were obtained from Simonsen Laboratories (Gilroy, 

Taconic Farms (Germantown, NY) and B6C3F, mice 

Male and female F344/N rats were obtained from 

Source and Specification of Animals 

Appendix L. 

feed composition and contaminants is provided in 

maintenance are given in Table 4. Information on 

were rotated weekly. Further details of animal 

and water was available ad libitum. Cages and racks 

available ad libitum, except during exposure periods, 

Rats and mice were housed individually. Feed was 

Animal Maintenance 

ings and body weights were recorded prior to the 

toxicity, mortality, and moribundity. Clinical findAll animals were observed twice daily for signs of 

Clinical Examinations and Pathology 
Materials and Methods 41 

thereafter, and at the end of the studies. 

start of the study, weekly for 13 weeks, monthly 

listed in Table 4. 

examined. Tissues examined microscopically are 

kidney, ovary), samples from each organ were 

tion. For all paired organs (i.e. adrenal gland, 

with hematoxylin and eosin for microscopic examinasectioned to a thickness of 5 to 6 pm, and stained 

lin, processed and trimmed, embedded in paraffin, 

fixed and preserved in 10% neutral buffered formafor grossly visible lesions, and all major tissues were 

At necropsy, all organs and tissues were examined 

only), and thymus of rats and mice were weighed. 

liver, lung, spleen, right testis (rats at 7 months 

15-month interim evaluations, the brain, right kidney, 

were performed on all rats and mice. At the 7- and 

A complete necropsy and microscopic examination 

Appendixes H and I. 

studies, and results of the studies are found in 

Methods used were those described for the 16-day 

and mice) and kidney (mice only) were determined. 

15 months. Concentrations of nickel in the lung (rats 

was performed on rats and mice evaluated at 7 and 

listed in Table 4. In addition, a tissue burden study 

retro-orbital sinus. The parameters evaluated are 

13-week study, except blood was drawn from the 

15 months, using the methods described for the 

were evaluated for hematology alterations at 

As many as five male and five female rats and mice 

bronchial lymph node, and nose of rats and mice. 

a quality assessment pathologist reviewed the lung, 

histotechnique was evaluated. For the 2-year studies, 

cy, the slide and tissue counts were verified, and the 

animal records and tables were compared for accuradent quality assessment laboratory. The individual 

and pathology tables were evaluated by an indepenaudit. The slides, individual animal data records, 

for inventory, slidehlock match, and wet tissue 

residual wet tissues were sent to the NTP Archives 

System. The microscopic slides, paraffin blocks, and 

entered into the Toxicology Data Management 

laboratory pathologist, and the pathology data were 

Microscopic evaluations were completed by the study 

chair, who reviewed the selected tissues and any 

ted to the NTP Pathology Working Group (PWG) 

The quality assessment report and slides were submitMcConnell et al. (1 986). 

separately or combined according to the guidelines of 

diagnosed lesions for each tissue type were evaluated 

subsequent analyses of the pathology data, the 

Boorman (1982) and Boorman et al. (1985). For 

dures have been described, in part, by Maronpot and 

ogists and the PWG. Details of these review procediagnoses represent a consensus of contractor patholgist, the diagnosis was changed. Thus, the final 

differed from the opinion of the laboratory patholorendered diagnoses. When the PWG consensus 

without any knowledge of dose groups or previously 

logic pathology. This group examined the tissues 

and other pathologists experienced in rodent toxicoPWG consisted of the quality assessment pathologist 

presented by the chair to the PWG for review. The 

pathologist, or lesions of general interest were 

ses between the laboratory and quality assessment 

administration, examples of disagreements in diagnocontaining examples of lesions related to chemical 

ogists existed. Representative histopathology slides 

between the laboratory and quality assessment patholother tissues for which a disagreement in diagnosis 

for the survival analyses are two sided. 

to identify dose-related trends. All reported P values 

groups for equality and Tarone’s (1975) life table test 

on survival used Cox’s (1 972) method for testing two 

Statistical analyses for possible dose-related effects 

dying from natural causes were not censored. 

were censored from the survival analyses; animals 

found dead of other than natural causes or missing 

and is presented in the form of graphs. Animals 

product-limit procedure of Kaplan and Meier (1958) 

The probability of survival was estimated by the 

Survival Analyses 

STATISTICAL METHODS 

examined microscopically. However, when 

as the numbers of animals affected at each site 

C3, and D3) and all nonneoplastic lesions are given 

the incidences of most neoplasms (Tables A3, B3, 

scopically. For calculation of statistical significance, 

number of animals with that site examined microsuch lesions at a specific anatomic site and the 

and D5 are given as the number of animals bearing 

as presented in Tables Al, A5, B1, B5, C1, C5, Dl, 

The incidences of neoplasms or nonneoplastic lesions 

Calculation of Incidence 
42 Nickel Sulfate Hexahydrate, NTP TR 454 

and Meier, 1958). 

of mortality from all other competing risks (Kaplan 

been observed at the end of the study in the absence 

estimate of the neoplasm incidence that would have 

each site-specific neoplasm, i.e., the Kaplan-Meier 

survival-adjusted neoplasm rate for each group and 

formed. Tables A3, B3, C3, and D3 also give the 

number of animals on which a necropsy was peror lymphoma), the denominators consist of the 

multiple potential sites of occurrence (e.g., leukemia 

microscopic evaluation, or when eoplasms had 

harderian gland, and mammary gland) before 

neoplasms in certain tissues (e.g., skin, intestine, 

macroscopic examination was required to detect 

neoplasm incidences (McKnight and Crowley, 1984). 

ences also provides a comparison of the time-specific 

this comparison of the time-specific neoplasm prevalHaseman (1986). When neoplasms are incidental, 

further described and illustrated by Dinse and 

prevalence analysis of Dinse and Lagakos (1983), 

method of adjusting for intercurrent mortality is the 

score test for the regression coefficient of dose. This 

groups were compared on the basis of the likelihood 

The neoplasm incidences of exposed and control 

if the fit of the model was not significantly enhanced. 

rated initially, and the quadratic term was eliminated 

Both linear and quadratic terms in time were incorpologistic function of chemical exposure and time. 

approach, neoplasm prevalence was modeled as a 

and thus did not affect the risk of death. In this 

ered as the result of death from an unrelated cause 

assumed that the diagnosed neoplasms were discovmethod used was logistic regression analysis, which 

not rapidly lethal. Thus, the primary statistical 

considered to be incidental to the cause of death or 

The majority of neoplasms in these studies were 

Analysis of Neoplasm Incidences 

neoplasm-bearing animals. 

1979), procedures based on the overall proportion of 

Armitage trend test (Armitage, 1971 ; Gart et al., 

plasms, and the Fisher exact test and the CochranTarone, 1975), appropriate for rapidly lethal neomethods include the life table test (Cox, 1972; 

tests are summarized in the appendixes. These 

statistical analysis were used, and the results of these 

In addition to logistic regression, other methods of 

to Haseman (1 984). 

further discussion of these statistical methods, refer 

to evaluate slected nonneoplastic lesions. For 

described in the preceding paragraphs were also used 

reported P values are one sided. The procedures 

were used in the analysis of neoplasm incidence, and 

overall dose-related trend. Continuity-corrected tests 

of each exposed group with controls and a test for an 

Tests of significance included pairwise comparisons 

proportion of affected animals. 

test was used, a procedure based on the overall 

detected at the interim evaluation, the Fisher exact 

function of chemical exposure and time. For lesions 

plastic lesion prevalence was modeled as a -logistic 

was a logistic regression analysis in which nonneonot rapidly lethal, the primary statistical analysis used 

considered to be incidental to the cause of death or 

Because all nonneoplastic lesions in this study were 

Analysis of Nonneoplastic Lesion Incidences 

(Morrison, 1976) to the transformed data to test for 

applying a multivariate nalysis of variance 

assumption. Treatment effects were investigated by 

bring the data into closer conformance with normality 

estrous stage), an arcsine transformation was used to 

observation period that an animal was in a given 

cytology data are proportions (the proportion of the 

(Hollander and Wolfe, 1973). Because the vaginal 

significance using, the Mann-Whitney U test 

test). Average severity values were analyzed for 

a monotonic dose-related trend (Dunnett’s or Dunn’s 

pairwise comparisons than a test that does not assume 

(Williams’ or Shirley’s test) was more appropriate for 

trends and to determine whether a trend-sensitive test 

was used to assess the significance of the dose-related 

Dunn (1964). Jonckheere’s test (Jonckheere, 1954) 

multiple comparison methods of Shirley (1977) and 

distributions, were analyzed using the nonparametric 

tissue burden data, which have typically skewed 

Hematology, spermatid, epididymal spermatozoa, and 

of Dunnett (1955) and Williams ( 197 1, 1972). 

using the parametric multiple comparison procedures 

approximately normal distributions, were analyzed 

ables. Organ and body weight data, which have 

control groups in the analysis of continuous varicance of pairwise comparisons between exposed and 

Two approaches were employed to assess the signifiAnalysis of Continuous Variables 
Materials and Methods 43 

sure levels. 

simultaneous equality of measurements across expo- The protocols for these studies and the results are 

given in Appendix E. 

effects. 

for neoplasms appearing to show compound-related 

et al., 1984, 1985) are included in the NTP reports 

from the NTP historical control database (Haseman 

certain instances. Consequently, neoplasm incidences 

the overall assessment of neoplasm incidence in 

evaluation, historical control data can be helpful in 

first and most appropriate control group used for 

Although the concurrent control group is always the 

Historical Control Data 

QUALITY ASSURANCE METHODS 

preparation of this Technical Report. 

resolved or were otherwise addressed during the 

assessed by NTP staff, so all comments had been 

at NIEHS. The audit findings were reviewed and 

findings are presented in the reports and are on file 

Report were conducted. Audit procedures and 

preliminary review draft of this NTP Technical 

pathology specimens, final pathology tables, and 

completeness and accuracy of the pathology data, 

assurance contractor. Separate audits covering 

audited retrospectively by an independent quality 

submitted to the NTP Archives, these studies were 

In addition, as records from the 2-year studies were 

Laboratory Practice Regulations (21 CFR, Part 58). 

compliance with Food and Drug Administration Good 

The 13-week and 2-year studies were conducted in 

GENETIC TOXICOLOGY 

induce mutations in L5178Y mouse lymphoma cells. 

assessed by testing the ability of the chemical to 

The genetic toxicity of nickel sulfate hexahydrate was 

Miller, 1977; Straus, 1981; Crawford, 1985). 

genesis and the somatic mutation theory (Miller and 

based on the electrophilic theory of chemical carcinodamage and to predict carcinogenicity in animals, 

study mechanisms of chemically induced DNA 

genetic toxicity tests were originally developed to 

in vitro and in vivo genetic toxicity tests. These 

structure and responses of the chemical in short-term 

of carcinogenicity in experimental animals from the 

develop a database that would permit the evaluation 

hydrate are part of a larger effort by the NTP to 

The genetic toxicity studies of nickel sulfate hexayet defined. 

chromosome aberration or micronucleus tests is not 

genicity of a positive response in bone marrow 

Salmonella test alone. The predictivity for carcinoSalmonella test improved the predictivity of the 

That is, no battery of tests hat included the 

plementarity among the in vitro genetic toxicity tests. 

were rodent carcinogens), and that there is no comcarcinogenicity (89 % of the Salmonella mutagens 

currently the most predictive in vitro test for rodent 

studies show that a positive response in Salmonella is 

the chemical being investigated. Data from NTP 

DNA and chromosome effects that can be induced by 

other tests can provide information on the types of 

et al., 1987; Zeiger et al., 1990), although these 

correlate well with rodent carcinogenicity (Tennant 

1991), Other in vitro genetic toxicity tests do not 

and/or at multiple tissue sites (Ashby and Tennant, 

with the induction of carcinogenicity in rats and mice 

icity and Salmonella mutagenicity is highly correlated 

genicity in rodents. The combination of electrophilreactivity), mutagenicity in Salmonella, and carcinopotential electrophilicity (structural alert to DNA 

There is a strong correlation between a chemical’s 
44 Nickel Sulfate Hexahydrate, NTP TR 454 

of Nickel Sulfate Hexahydrate 

Experimental Design and Materials and Methods in the Inhalation Studies 

TABLE 4 

16-Day Studies 13-Week Studies 2-Year Studies 

(Albuquerque, NM) 

Research Institute 

Lovelace Inhalation Toxicology 

Study Laboratory 

Mice: B6C3F, 

Rats: F344lN 

Strain and Species 

(Frederick, MD) 

Frederick Cancer Research Facility 

Animal Source 

Mice: 21 days (males) or 22 days 

Rats: 19 days (males) or 20 days 

Time Held Before Studies 

(females) 

(females) 

7 weeks 

Average Age When Studies Began 

Mice: 16 September (males) 

Rats: 23 September (males) 

Date of First Dose 

or 17 September (females) 1985 

or 24 September (females) 1985 

6 hours per day, 5 days per week 

Duration of Dosing 

for 16 days 

Mice: 1 October (males) or 

Rats: 8 October (males) or 

Date of Last Dose 

2 October (females) 1985 

9 October (females) 1985 

(Albuquerque, NM) 

Research Institute 

Lovelace Inhalation Toxicology 

Mice: B6C3Fl 

Rats: F344lN 

(Gilroy, CA) 

Simonsen Laboratories 

19 days (males) or 20 days (females) 

7 weeks 

Mice: 9 June (males) 

Rats: 2 June (males) 

or 10 June (females) 1986 

or 3 June (females) 1986 

6 hours per day, 5 days per week 

for 13 weeks 

11-12 September (females) 1986 

Mice: 9-10 September (males) or 

4-5 September (females) 1986 

Rats: 2-3 September (males) or 

(Albuquerque, NM) 

Research Institute 

Lovelace Inhalation Toxicology 

Mice: B6C3Fl 

Rats: F344M 

Mice: Simonsen Laboratories 

Rats: Taconic Farms 

(Gilroy, CA) 

(Germantown, NY) 

Mice: 11 days 

Rats: 10 days 

6 weeks 

Mice: 30 May 1988 

Rats: 20 June 1988 

6 hours per day, 5 days per week 

for 104 weeks 

Rats 

19-20 September 1989 

15-Month interim evaluation: 

3-4 January 1989 

?'-Month interim evaluation: 

Terminal sacrifice: 15 June 1990 

15-Month interim evaluation: 

20-21 December 1988 

7-Month interim evaluation: 

Terminal sacrifice: 25 May 1990 

29-30 August 1989 

Mice 
Materials and Methods 45 

TABLE 4 

of Nickel Sulfate Hexahydrate (continued) 

Experimental Design and Materials and Methods in the Inhalation Studies 

16-Day Studies 13-Week Studies 

~ ~~ 

2-Year Studies 

Mice: 2 October (males) 

Rats: 9 Ootober (males) 

Necropsy Dates 

Mice: 10-1 1 September (males) 

Rats: 3-4 September (males) 

or 3 October (females) 1985 

or 10 October (females) 1985 

or 12-13 September (females) 1986 

or 5-6 September (females) 1986 

9 weeks 

Average Age at Necropsy 

Tissue burden studies: 4 or 5 male 

Core studies: 5 male and 5 female 

Sue of Study Groups 

and female rats and mice 

rats and mice 

20 weeks 

Tissue burden studies: 5 or 6 male and 

Core studies: 10 male and 10 female 

female rats and mice 

rats and mice 

mean body weights. 

groups of approximately equal initial 

Animals were distributed randomly into Same as 16-day studies 

Method of Distribution 

Rats 

20-21 September 1989 

15-Month interim evaluation: 

4-5 January 1989 

7-Month interim evaluation: 

18-21 June 1990 (females) 

22, 25-26 June 1990 (males) 

Terminal sacrifice: 

Mice 

15-Month interim evaluation: 

21-22 December 1988 

7-Month interim evaluation: 

Terminal sacrifice: 

30-31 August 1989 

29 May-4 June 1990 (females) 

5-7 June 1990 (males) 

Terminal sacrifice: 110-1 11 weeks 

15-Month interim evaluation: 

7-Month interim evaluation: 

72 weeks 

35 weeks 

Core studies: 

2-Year studies: 

15-Month interim evaluation: 

7-Month interim evaluation: 

53-54 male and 53-55 female rats 

5 male and 5 female rats and mice 

5 male and 5 female rats and mice 

mice 

and 61-62 male and 60-61 female 

7-Month interim evaluation: 

Tissue burden studies: 

5 male and 5 female rats and mice 

5 male mice, and 5 female mice 

6 or 7 male rats, 5 to 7 female rats, 

15-Month interim evaluation: 

Same as 16-day studies 
46 Nickel Sulfate Hexahydrate, NTP TR 454 

of Nickel Sulfate Hexahydrate (continued) 

Experimental Design and Materials and Methods in the Inhalation Studies 

TABLE 4 

16-Day Studies 13-Week Studies 2-Year Studies 

1 

Animals per Cage 

1 1 

chamber unit 

Toe clip, ear tag, and location within 

Method of Animal Identification 

Toe clip, ear tag, and location within 

(mice) 

Tail tattoo (rats and mice) and ear tag 

. chamber unit 

changed at least once weekly 

except during exposure periods; 

Gardners, PA), available ad libitum, 

ration (Zeigler Brothers, Inc., 

NIH-07 open formula rat and mouse 

Diet 

Same as 16day studies 

daily 

available ad libitum; checked twice 

(Fdstrom Industries, Waterford, WI), 

supply) via automatic watering system 

Tap water (Albuquerque municipal 

Water Distribution 

Same as 16-day studies 

every 4 exposure days; changed weekly 

Aberdeen, MD), cage units rotated units were rotated once weekly 

Stainless steel (Hazleton Systems, Inc., Same as 16-day studies, except cage 

Cages 

Kalamazoo, MI), changed twice daily 

Specialties Paper, Inc., 

Techboard untreated paper (Shepherd 

BeddingKageboard 

Same as 16-day studies 

as needed 

(Flanders, Washington, DC), changed 

High-efficiency particulate air filter 

RoomKhamber Air Supply Filters 

Same as 16day studies 

MD), changed weekly 

Stainless steel (Hazleton, Aberdeen, 

Chambers 

Fluorescent light: 12 hourslday 

Relative humidity: 13% to 82% 

Temperature: 17.0" to 28.2" C 

Chamber Environment 

Same as 16-day studies 

Same as 16-day studies 

Same as 16-day studies 

units rotated once weekly 

Products, Inc., Maywood, N.J.), cage 

Stainless steel wire mesh (Lab 

Same as 16-day studies 

Same as 16-day studies 

Same as 16-day studies 

Fluorescent light: 12 hourslday 

Relative humidity: 43% to 76% 

Temperature: 19.1" to 27.6" C 

Chamber air changes: 9-21/hour 

Fluorescent light: 12 hourdday 

Relative humidity: 8% to 99% 

Temperature: 17.2" to 29.6"C 
Materials and Methods 47 

of Nickel Sulfate Hexahydrate (continued) 

Experimental Design and Materials and Methods in the Inhalation Studies 

TABLE 4 

16-Day Studies 13-Week Studies 2-Year Studies 

Doses 

. Core studies: 0, 3.5,*7, 15, 30, or 

6.1, or 12.2 mg nickel/m’) 

hydrate/m3 (0, 0.7, 1.4, 3.1, 

60 mg nickel sulfate hexa30 mg/m3 

Tissue burden studies: 0, 3.5, 15, or 

day 5, and at the end of the studies. 

animals were weighed initially, on 

observations were recorded and 

Observed twice daily; clinical 

Type and Frequency of Observation 

anesthesia 

Exsanguination under halothane 

Method of Sacrifice 

and thymus. 

right kidney, liver, lung, right testis, 

Organs weighed were brain, heart, 

Necropsy performed on all animals. 

Necropsy 

None 

Clinical Pathology 

nickel/m3) 

0.11, 0.22, or 0.44 mg 

hydrate/m’ (0, 0.03, 0.06, 

or 2 mg nickel sulfate hexaCore studies: 0, 0.12. 0.25, 0.50, 1, Rats: 0, 0.12, 0.25. or 0.5 mg nickel 

2 mg/m3 

tissue burden studies) 

0.06. 0.11 mg nickel/m3) (core and 

sulfate he~ahydratelm~ (0, 0.03, 

tissue burden studies) 

0.11, or 0.22 mg Ni/m3) (core and 

sulfate hexahydrate/m3 (0, 0.06, 

Mice: 0, 0.25. 0.5, or 1 mg nickel 

Tissue burden studies: 0, 0.12, 0.5, or 

and at the end of the studies. 

animals were weighed initially, weekly, 

observations were recorded and 

Observed twice daily; clinical 

Same as 16-day studies 

the end of the studies. 

13 weeks, monthly thereafter, and at 

recorded initially, weekly for 

weighed and clinical observations were 

Observed twice daily; animals were 

anesthesia 

Exsanguination under carbon dioxide 

and thymus. 

right kidney, liver, lung, right testis, 

Organs weighed were brain, heart, 

Necropsy performed on all animals. 

(rats at 7 months only), and thymus. 

kidney, liver, lung, spleen, right testis 

interim evaluations were brain, right 

Organs weighed at the 7- and 15-month 

Necropsy performed on all animals. 

nucleated erythrocytes. 

leukocytes and differential, and 

concentration, reticulocytes, total 

mean erythrocyte hemoglobin 

erythrocytes, mean erythrocyte volume, 

Hemnfology: hematocrit, hemoglobin, 

by cardiac puncture for hematology. 

Blood was collected from all animals 

differential, and nucleated erythrocytes. 

reticulocytes, total leukocytes and 

erythrocyte hemoglobin concentration, 

mean erythrocyte hemoglobin, mean 

erythrocytes, mean erythrocyte volume, 

Hematology: hematocrit, hemoglobin, 

the 15-month interim evaluation. 

male and five female rats and mice at 

retroorbital sinus of as many as five 

Blood was collected from the 
48 Nickel Sulfate Hexahydrate, N” TR 454 

of Nickel Sulfate Hexahydrate (continued) 

Experimental Design and Materials and Methods in the Inhalation Studies 

TABLE 4 

16-Day Studies 13-Week Studies 2-Year Studies 

thymus. 

spleen (15 mglm’ only), testis, and 

(bronchial and mediastinal), nose, 

lung, respiratory tract lymph nodes 

from 3.5, 7, and 15 mglm’ rats: liver, 

following target organs were examined 

bladder, and uterus. In addition, the 

thymus, thyroid gland, trachea, urinary 

(forestomach and glandular), testis, 

vesicle, skin, spleen, stomach 

prostate, salivary gland, seminal 

gland, preputial gland (rats only), 

only), parathyroid gland, pituitary 

ovary, pancreas, pancreatic islets (rats 

mesenteric), mammary gland, nose, 

(bronchial, mandibular, mediastinal, 

larynx, liver, lung, lymph nodes 

(duodenum, jejunum, ileum), kidneys, 

colon, rectum), small intestine 

only), heart, large intestine (cecum, 

oviduct, esophagus, gallbladder (mice 

gland (rats only), epididymis or 

adrenal gland, bone, brain, clitoral 

masses, the tissues examined included: 

addition to gross lesions and tissue 

and on 0, 3.5, and 7 mglm’ mice. In 

performed on 0, 30, and 60 mglm’ rats 

Complete histopathology was 

Histopathology 

only) (see Appendixes H and I) 

Lung (rats and mice) and kidney (rats 

Tissue Burden Analyses 

None 

Sperm Morphology and Vaginal 4 

mediastinal). 

lymph nodes (bronchial and 

mice: lung, nose, and respiratory tract 

selected exposure groups of rats and 

following organs were examined from 

bladder, and uterus. In addition, the 

thymus, thyroid gland, trachea, urinary 

(forestomach and glandular), testis, 

vesicle, skin, spleen, stomach 

prostate, salivary gland, seminal 

gland, preputial gland (rats only), 

only), parathyroid gland, pituitary 

ovary, pancreas, pancreatic islets (rats 

mesenteric), mammary gland, nose, 

(bronchial, mandibular, mediastinal, 

larynx, liver, lung, lymph nodes 

(duodenum, jejunum, ileum), kidneys, 

colon, rectum), small intestine 

only), heart, large intestine (cecum, 

oviduct, esophagus, gallbladder (mice 

clitoral gland (rats only), epididymis or 

included: adrenal gland, bone, brain, 

tissue masses, the tissues examined 

mice. In addition to gross lesions and 

performed on 0 and 2 mglm’ rats and 

Complete histopathology was 

only) (see Appendixes H and I) 

Lung (rats and mice) and kidney (rats 

Clytology Evaluations 

cycle length. 

frequency of estrous stages and estrous 

parameters evaluated were relative 

for vaginal cytology evaluations. The 

in the 0, 0.5, 1, and 2 mglm’ groups 

of the studies from all female animals 

to 7 consecutive days prior to the end 

Vaginal samples were collected for up 

caudae, and right testis were weighed. 

motility. The right epididymis, right 

were sperm density, morphology, and 

evaluations. The parameters evaluated 

exposure groups for sperm morphology 

animals in the 0, 0.5, 1 and 2 mglm’ 

samples were collected from all male 

At the end of the studies sperm 

bladder, and uterus. 

thymus, thyroid gland, trachea, urinary 

(forestomach and glandular), testis, 

vesicle, skin, spleen, stomach 

mice), prostate, salivary gland, seminal 

preputial gland (except 0 mg\m’ male 

parathyroid gland, pituitary gland, 

pancreas, pancreatic islets (rats only), 

mammary gland, nose, ovary, 

mandibular, mediastinal, mesenteric), 

lung, lymph nodes (bronchial, 

jejunum, ileum), kidneys, larynx, liver, 

rectum), small intestine (duodenum, 

heart, large intestine (cecum, colon, 

esophagus, gallbladder (mice only), 

gland, epididymis or oviduct, 

adrenal gland, bone, brain, clitoral 

masses, the tissues examined included: 

addition to gross lesions and tissue 

performed on all rats and mice. In 

Complete histopathology was 

only) (see Appendixes H and I) 

Lung (rats and mice) and kidney (mice 

None 
49 

RESULTS 

16-D~y STUDY 

RATS 

labored, and activity levels were reduced. 

Respiration rates were increased, breathing was 

observed around the noses and chins of the animals. controls. 

noticeably thin, and red staining of the hair was were generally significantly less than those of the 

the controls. Rats in all exposure groups became weights of all exposed groups of males and females 

exposed groups were significantly lower than those of (Table Fl). The absolute and relative thymus 

study, and the final mean body weights of all significantly greater than those of the controls 

(Table 5). All exposed groups lost weight during the males and of all exposed groups of females were 

60 mg/m3 females died before the end of the study Absolute and relative lung weights of 60 mg/m3 

Two 60 mg/m3 males, one 30 mg/m3 female, and all 

Survival and Body Weights of Rats in the 16-Day Inhalation Study of Nickel Sulfate Hexahydrate 

TABLE 5 

Mean Body Weightb (2) 

Change Relative to Controls 

Final Weight 

(mg/m3) 

Dose Survivala Initial Final 

(%) 

Male 

60 

30 

15 

7 

3.5 

0 

Female 

60 

30 

15 

7 

3.5 

0 

315‘ 

515 

515 

515 

515 

515 

0/5e 

4/5d 

515 

515 

515 

515 

161 f 3 

164 f 2 

160 f 6 

165 f 5 

164 f 4 

167 f 5 

123 f 3 

123 f 3 

122 f 3 

126 f 3 

123 f 3 

125 f 1 

102 f o** 

123 f 9** 

127 f 2** 

136 f 2** 

162 f 8** 

225 f 5 

93 f 4** 

100 f 5** 

105 f 2** 

120 f 7** 

147 f 4 

-8 f 4** 

-2 f 6** 

58 f 3 

-58 f 4** 

-41 f 9** 

-33 f 4** 

-29 f 6 

-22 f 2 

-21 f 2 

-3 f 4 

22 f 3 

- 

45 

55 

56 

60 

72 

63 

68 

71 

a2 

a Number of animals surviving at 16 dayslnumber initially in group 

** Significantly different (P50.01) from the control group by Williams’ or Dunnett’s test 

Day of death: 6 

Days of death: 5, 6 

the study. No final mean body weights or weight changes were calculated for groups with 100% mortality. 

Weights and weight changes are given as mean f standard error. Subsequent calculations are based on animals surviving to the end of 

e Days of death: four on day 5, one on day 16 
50 Nickel Sulfate Hexahydrate, NTP TR 454 

discolorations in lung or other organs. 

decrease in thymus size and foci of red or purple 

and generalized toxicity. Such findings include a 

killed moribund because of marked body weight loss 

typically observed in animals that die early or are 

hexahydrate were considered secondary effects 

in male and female rats exposed to nickel sulfate 

opened. The majority of the gross lesions observed 

observed in controls when the thoracic cavity is 

greater did not collapse to the xtent normally 

At necropsy, the lungs of rats exposed to 7 mg/m3 or 

mixed inflammatory cell infiltrate in the alveolar 

an accumulation of alveolar macrophages and a 

and necrosis. Inflammation in the lungs consisted of 

hydrate, there was inflammation with degeneration 

In the lungs of rats exposed to nickel sulfate hexanodes, and noses of male and female rats (Table 6). 

present in the lungs, bronchial and mediastinal lymph 

Treatment-related histopathologic lesions were 

cytes. 

eration; and a slight decrease in the size of hepatospleen, thymus, and lymph nodes; testicular degenspecific lesions included: lymphoid depletion in the 

toxicity and marked body weight loss. These nonconsidered nonspecific and secondary to generalized 

few animals from the higher exposure groups were 

passage. Other histopathologic lesions present in a 

the anterior portion of the dorsal meatus in the nasal 

thinning of the olfactory epithelial layer, primarily in 

exposed groups of rats. Atrophy consisted of a 

the nasal olfactory epithelium was present in all 

paracortical regions. Mild to moderate atrophy of 

by an increased number of lymphocytes in the 

respiratory tract, there was hyperplasia characterized 

mediastinal lymph nodes associated with the lower 

nickel sulfate hexahydrate. In the bronchial and 

epithelium occurred in all groups of rats exposed to 

airways. Degeneration or necrosis of bronchiolar 

inflammatory cells were present in the terminal 

septae. Necrotic cell debris and fibrin containing 

of Nickel Sulfate Hexahydrate 

Incidences of Selected Nonneoplastic Lesions in Rats in the 16-Day Inhalation Study 

TABLE 6 

0 mg/m3 3.5 mg/m3 7 mg/m3 15 mg/m3 30 mglm3 60 mg/m3 

~~ ~ ~ 

Lunga 

Male 

5 

2 

Bronchiolar Epithelium 0 

0 

Lymph Node, Mediastinal 2 

0 

Respiratory Epithelium 0 

Olfactory Epithelium 0 

5 

0 

5 5 5 

5** (1.2)' 5** (2.6) 5** (2.4) 5** (1.8) 

5** (1.0) 5** (2.8) 5** (2.0) 5** (1.8) 

5 4 5 3 

3 3 3 3 

4 (1.8) 4 (1.5) 5* (1.8) 0 

2 (1.5) 3 (1.7) 2 (2.0) 0 

5 5 5 5 

5** (2.6) 5** (2.8) 5** (3.0) 5** (3.0) 4* (3.3) 

1 (1.0) 1 (1.0) 5** (2.2) 4* (2.8) 0 

5 5 

Degeneration, 

Inflammationb 

5 

1 (2.0) 

4* (2.0) 

0 

Lymph Node, Bronchial 

Hyperplasia 

0 

3 

Hyperplasia 

Nose 5 

Degeneration, 

Atrophy, 

(continued) 
Results 51 

of Nickel Sulfate Hexahydrate (continued) 

Incidences of Selected Nonneoplastic Lesions in Rats in the 16-Day Inhalation Study 

TABLE 6

0 mg/m3 3.5 mg/m3 7 mg/m3 15 mglm’ 30 mg/m3 60 mg/m3 

Female 

Lung 

Necrosis, Bronchial 

Degeneration, Bronchial 

Inflammation 

Epithelium 

Epithelium 

0 

5 5 5 

5** (1.8) 5** (1.2) 5** (3.0) 

5 

5** (1.8) 

5 5 

5** (1.2) 

0 5** (1.2) 5** (2.2) 

0 0 0 

5** (2.4) 

0 

4* (2.3) 0 

0 4* (1.8) 

Lymph Node, Bronchial 

Hyperplasia 

Lymph Node, Mediastinal 

Hyperplasia 

0 

3 

3 (1.7) 3 (1.7) 

5 4 

3 (1.3) 4* (1.8) 

4 4 

2 (2.5) 

3 

4* (2.3) 

4 

0 

2 

0 

4 

0 

3 

0 

2 

0 

4 

Nose 

Atrophy, 

Olfactory Epithelium 

Degeneration, 

Respiratory Epithelium 

5 5 5 5 5 5 

0 5** (2.0) 5** (3.0) 5** (3.0) 5** (2.4) 5** (3.2) 

0 0 0 5** (1.4) 2 (2.5) 2 (1.5) 

a Number of animals with organ examined microscopically 

** P10.01 

* Significantly different (PSO.05) from the control by the Fisher exact test 

Average severity of lesions in affected animals: 1 = minimal; 2 = mild; 3 = moderate; 4 = marked 

Number of animals with lesion 
52 Nickel Sulfate Hexahydrate, NTP TR 454 

The concentrations of nickel inthe lungs of concentration of nickel in the kidney of males and 

males and females exposed to 3 3, 15, or 30 mg/m3 females exposed to 30 mg/m3 was significantly 

was significantly greater than those in the lung of greater than those in the control animals 

control animals (Tables 7 and Hl). The (Table H2). 

Lung Weight and Lung Burden in Rats in the 16-Day Inhalation Study of Nickel Sulfate Hexahydratea 

TABLE 7 

0 mg/m3 3.5 mg/m3 15 mg/m3 30 mg/m3 

Male 

n 

pg Ni/g control lung 

pg Nilg lung 

pg Nillung 

Absolute lung wt (g) 

Female 

n 

pg Nilg control lung 

pg Nilg lung 

pg Ni/lung 

Absolute lung wt (g) 

0.920 f 0.034 

5 

- b 

- 

- 

5 

0.762 f 0.038 - 

- 

- 

5 

7.300 f 0.355** 

5.100 f 0.318** 

6.700 f 0.326** 

1.322 f 0.043** 

5 

10.060 f 0.434** 

7.640 f 0.333** 

9.400 f 0.517** 

1.230 f 0.039** 

4 

13.650 f 1.436** 

9.425 f 1.055** 

12.575 f 1.326** 

1.353 f 0.084** 

5 

17.060 f 1.694** 

10.500 f 1.063** 

12.980 f 1.293** 

1.244 f 0.026** 

5 

10.560 f 1.643** 

7.700 f 1.190** 

9.700 f 1.522** 

1.262 f 0.027** 

4 

13.025 f 3.355** 

9.225 f 2.415** 

9.900 f 2.539** 

1.075 f 0.032** 

b Results were below 0.155 pg Ni (the limit of detection), or below the level of quantitation. 

a Mean f standard error; statistical tests were performed on unrounded data. 

** Significantly different (PSO.01) from the control group by Dunnett’s test (lung weight) or Shirley’s test (lung burden parameters). 
Results 53 

clinical findings observed. 

were similar to those of the controls. There were no 

gains of all exposed groups of males and females 

Final mean body weights and mean body weight 

animals survived to the end of the study (Table 8). 

One 2 mg/m3 male died during week 3; all other 

ISWEEK STUDY 

margination or homing, tissue migration, and recircuincreases can also occur as a result of altered cell 

numbers can be related to increased production, 

elevated peripheral neutrophil and lymphocyte 

mediastinal lymph node hyperplasia observed. While 

groups and may be a reflection of the bronchial and 

phocytosis also occurred in the 1 and 2 mg/m3 female 

pulmonary inflammation in these animals. A lymbe consistent with the presence of chronic active 

males exposed to 1 or 2 mg/m3; this condition would 

females exposed to 0.25 mg/m3 or greater and in 

increased segmented neutrophil numbers, occurred in 

Table G1. A mature neutrophilia, evidenced by 

Hematology data for the rats are presented in 

biologically significant. 

MCHC values are an enigma nd probably not 

hematocrit values occurred. The slightly increased 

hemolysis or altered hemoglobin concentrations or 

tration or hematocrit. There are no indications that 

in vitro) or alterations in the hemoglobin concenhave been related to erythrocyte hemolysis (in vivo or 

in all exposed groups of males. Increases in MCHC 

in the mean cell hemoglobin concentration (MCHC) 

hematologic parameters. There were slight increases 

lesions could account for the observed increases in 

microscopically in 1 and 2 mg/m3 females, and these 

present study, pulmonary lesions were observed 

transport, and reduced atmospheric oxygen. In the 

disease, altered erythrocyte/hemoglobin oxygen 

been observed with pulmonary or cardiovascular 

dary erythrocytosis, related to tissue hypoxia, has 

a mild dehydration (relative erythrocytosis). Seconin 1 and 2 mg/m3 females would be consistent with 

crit, hemoglobin concentration, and erythrocyte count 

lymphocyte numbers. Minimal increases in hematogreater was a result of the changes in neutrophil and 

numbers in female rats exposed to 0.5 mg/m3 or 

lation. The occurrence of increased leukocyte 

Survival and Body Weights of Rats in the 13-Week Inhalation Study of Nickel Sulfate Hexahydrate 

TABLE 8

Mean Body Weightb (g) 

(%) 

Change Relative to Controls 

Final Weight 

Dose Survivala Initial Final 

(mglm') 

Male 

2 

1 10110 

0.5 10110 

0.25 10110 

0.12 10/10 

0 10/10 

131 f 3 

135 f 3 

133 f 4 

135 f 3 

133 f 5 

134 f 4 

311 f 5 

334 f 5 

317 f 5 

339 f 6 

325 f 4 

328 f 5 

181 * 4 

199 f 5 

184 f 4 

203 f 7 

192 f 5 

195 f 4 

9\10' 

Female 

0 10/10 

0.12 10110 

0.25 10/10 

0.5 10110 

1 10/10 

2 10110 111 f 2 

110 f 2 

109 f 3 

110 f 2 

106 f 4 

112 f 2 

187 f 3 

198 f 3 

192 f 3 

193 f 3 

189 f 4 

197 f 4 

76 f 2 

88 f 2 

83 f 2 

83 f 3 

83 f 3 

84 f 4 

95 

102 

96 

103 

99 

95 

101 

98 

98 

96 

a Number of animals surviving at 13 weekslnumber initially in group 

Week ofdeath: 3 

the study. Differences from the control group were not significant by Dunnett's test. 

Weights and weight changes are given as mean f standard error. Subsequent calculations are based on animals surviving to the end of 
54 Nickel Sulfate Hexahydrate, NTP TR 454 

No significant differences in sperm morphology or increased with increasing exposure concentration. 

vaginal cytology between exposed and control rats The number of alveolar macrophages also increased 

were observed (Table Jl). with increasing exposure concentration; in 0.25 and 

0.5 mg/m3 groups, there were focal aggregates of 

three female 1 mg/m3 rats. 

exposed to 2 mg/m3 and inthree male and 

lymph nodes were also grossly enlarged in most rats 

two females from the 0.5 mg/m3 groups. Mediastinal 

ment of these nodes was observed in one male and 

rats in the 1 and 2 mg/m3 exposure groups; enlargeenlargement of the bronchial lymph nodes of most 

creased with exposure concentration. There was 

Both the incidence and number of these foci nrats from groups exposed to 0.5 mg/m3 or greater. 

were scattered throughout the lung ‘parenchyma of 

lymph nodes. Numerous white foci (1 to 2 mm) 

observed in the lung and bronchial and mediastinal 

necropsy, treatment-related gross lesions were 

greater than those of the controls (Table F2). At 

males and females were generally significantly 

and relative lung weights of all exposed groups of 

With the exception of 0.12 mg/m3 rats, the absolute 

tory epithelium was observed in all rats exposed to 

nodes observed at necropsy. Atrophy of the olfacseverity coincided with an increased size of lymph 

rats exposed to 0.5 mg/m3 or greater; the increasing 

paracortical region. Hyperplasia was observed in 

increase in lymphocytes, primarily located in the 

there was lymphoid hyperplasia characterized by an 

lymph nodes associated with the respiratory tract, 

enlargement of Type I1 cells lining the septae. In the 

focal areas of inflammation, there was often a slight 

neutrophils, and fibroblasts in the interstitium. In 

increase in mononuclear inflammatory cells, a few 

slight thickening of alveolar septae attributed to an 

Chronic active inflammation was characterized by 

around blood vessels scattered throughout the lung. 

trates of lymphocytes and macrophages were present 

the alveolar spaces. Minimal focal interstitial infilproteinaceous material and a few neutrophils within 

these macrophages along with granular, eosinophilic 

and spectrum of inflammatory changes in the lung of the nasal passages. 

and 0.25 mg/m3 male and female rats. The severity present primarily in the region of the dorsal meatus 

within the pulmonary alveoli were observed in 0.12 decrease in the number of cells. The atrophy was 

Minimal increases in the number of macrophages the apical portion of the cells as well as a slight 

nodes, and noses of male and female rats (Table 9). attributed to a decrease in the amount of cytoplasm in 

present in the lungs, bronchial and mediastinal lymph thelia1 layer in the nasal passages. Atrophy was 

Treatment-related histopathologic lesions were reduction in the normal thickness of this neuroepi1 or 2 mg/m3 and consisted of a minimal to mild 
Results 55 

of Nickel Sulfate Hexahydrate 

Incidences of Selected Nonneoplastic Lesions in Rats in the 13-Week Inhalation Study 

TABLE 9 

0 mg/m3 0.12 mg/m3 0.25 mg/mJ 0.5 mg/m3 1 mg/m3 2 mglm' 

Lunga 

Male 

Alveolar Macrophage 

10 

Inflammation, Chronic Active 0 0 

Interstitial Infiltrate 1 (1.0) 0 

0 

Olfactory Epithelium, Atrophy 0 

10 

0 

Lymph Node, Mediastinal 5 

0 

5 

10 10 10 9 

0 2 (1.0) lo** (1.5) 8** (1.3) 

1 (1.0) 5 (1.0) lo** (1.0) 9** (1.1) 

lo** (1.O)C lo** '(1.0) lo** (1.0) lo** (2.4) 9** (3.6) 

9** (1.7) 

10 9 

0 9** (1.3) 7* (2.6) 

10 9 

0 4 (1.0) 8** (1.6) 9** (2.4) 

8 10 9 

10 

Hyperplasiab 

Lymph Node, Bronchial - d 10 

Hyperplasia 

- - 10 

Hyperplasia 

Nose 

0 

10 

0 

10 10 

1 (1.0) lo** (1.0) 

Female 

Lung 

Alveolar Macrophage 

10 

Inflammation, Chronic Active 0 

Interstitial Infiltrate 0 

0 

10 10 10 10 

0 4* (1.0) lo** (1.3)lo** (1.0) 

0 6** (1.0) lo** (1.0) lo** (1.0) 

lo** (1.0) lo** (1.1) lo** (2.2) lo** (3.6) 

10 

Hyperplasia 

0 

0 

8** (1.0) 

Lymph Node, Bronchial 

Olfactory Epithelium, Atrophy 0 

IO 

0 

Lymph Node, Mediastinal 9 

0 

I - 

0 

10 10 

10 

9** (1.4) lo** (2.3) 

9 10 

Hyperplasia 

10 

0 

8 

4 (1.0) 

- - 10 

Hyperplasia 8** (1.5) 9** (1.6) 

Nose 

0 

10 10 10 

1 (1.0) 2 (1.0) lo** (1.0) lo** (1.2) 

10 

a Number of animals with organ examined microscopically 

** P10.01 

* Significantly different (PSO.05) from the control group by the Fisher exact test 

Organ not examined at this exposure concentration 

Average severity of lesions in affected animals: 1 = minimal; 2 = mild; 3 = moderate; 4 = marked 

Number of animals with lesion 
56 Nickel Sulfate Hexahydrate, NTP TR 454 

The concentrations of nickel in the lung of rats (Tables 10 and H3). The concentrations of nickel 

exposed to 0.5 or 2 mg/m3 were significantly in the kidney of males and females exposed to 0.5 or 

greater than those in the controls at 4, 9, and 2 mg/m3 were similar to those in the controls 

13 weeks for males and at 13 weeks for females (Table H4). 

Lung Weight and Lung Burden in Rats in the 13-Week Inhalation Study of Nickel Sulfate Hexahydratea 

TABLE 10 

0 mg/m3 0.12 mg/m3 0.5 mg/m3 2 mg/m3 

n 

Male 

4 weeks 

pg Nilg control lung 

pg Nilg lung 

9 weeks 

pg Nilg control lung 

pg Nilg lung 

13 weeks 

pg Nilg control lung 

pg Nilg lung 

pg Nillung 

Absolute lung wt (g) 

13 weeks 

pg Nilg control lung 

pg Nilg lung 

pg Ni/lung 

Absolute lung wt (g) 

6 

- 

- 

- 

- 

0.140 f 0.140 

0.120 f 0.120 

0.145 f 0.145 

1.09 f 0.06 

0.835 f 0.033 - 

- 

- 

6 

1.693 f 0.200** 

1.357 f 0.135** 

2.695 f 0.065** 

2.153 f 0.086** 

1.450 f 0.158** 

1.055 f 0.075** 

1.490 f 0.163** 

1.39 f 0.07** 

1.765 f 0.104** 

1.157 f 0.050** 

1.395 f 0.083** 

1.201 f 0.034** 

6 

4.562 f 0.240**' 

2.696 f 0.124**' 

8.348 f 0.446** 

4.770 f 0.207** 

6.368 f 0.161** 

3.348 f 0.067** 

6.557 f 0.166** 

1.96 f 0.06** 

6.897 f 0.486** 

3.725 f 0.270** 

5.460 f 0.384** 

1.469 f 0.040** 

' n=5 

a Mean f standard error; statistical tests were performed on unrounded data. 

** Significantly different (PsO.01) from the control group by Williams' test (lung weight) or Shirley's test (lung burden parameters) 

Results were below 0.216 pg Ni (the limit of detection), or below the level of quantitation. 

Dose Selection Rationale: Based on lung weight nickel sulfate hexahydrate exposure concentrations 

increases and increased incidence and severity of selected for the 2-year inhalation study in rats were 

lung lesions in 1 and 2 mg/m3 males and females, 0.12, 0.25, and 0.5 mg/m3. 
Results 57 

%YEAR STUDY 

administration. 

clinical findings considered related to chemical 

(Figure 3 and Tables 12 and 13). Rats exhibited no 

controls throughout the second year of the study 

were slightly lower (6% to 9%) than those of the 

study; mean body weights of 0.5 mg/m3 female rats 

icant differences in survival were observed. 

Kaplan-Meier survival curves (Figure 2). No signifand female rats are shown in Table 11 and in the 

Estimates of 2-year survival probabilities for male 

Survival 

Body Weights and Clinical Findings Hematology Mean body weights of exposed groups of male rats No biologically significant hematology differences 

were similar to those of the controls throughout the occurred in male or female rats (Table G2). 

Survival of Rats in the 2-Year Inhalation Study of Nickel Sulfate Hexahydrate 

TABLE 11 

Male 

Animals initially in study 

Mean survival (days)' 

Percent probability of survival at end of studyb 

Animals surviving to study tennination 

Natural deaths 

Moribund kills 

Accidental deatha 

15-Month interim evaluationa 

7-Month interim evaluationa 

survival analysisd 

64 63 63 63 

30 

16 

4 

34 

0 

5 

5 

641 

30 

16 

7 

30 

0 

5 

5 

663 

1 

5 

5 

36 

18 

3 

31 

654 

4 

28 

0 

5 

5 

654 

40 

21e 

P=0.373N P=0.730N P=0.59N P=0.418N 

Female 

Animals initially in study 

Mean survival (days) 

Percent probability of survival at end of study 

Animals surviving to study termination 

Natural deaths 

Moribund kills 

Missinga 

Missexeda 

Accidental deatha 

15-Month interim evaluationa 

?'-Month interim evaluationa 

Survival analysis 

63 63 64 65 

0 

0 

0 

5 

5 

676 

42 

22 

4 

27 

32 

17 

4 

32 

0 

0 

0 

5 

5 

65 1 

0 

1 

0 

5 

5 

690 

53 

28 

3 

22 

1 

0 

1 

5 

5 

624 

55 

29 

3 

21 

P=0.156N P=O. 160 P=0.299N P=0.510N 

a Censored from survival analyses 

1972) with the controls are in the dosed columns. A negative trend or a lower mortality in a dose group is indicated by N. 

The result of the life table trend test (Tarone, 1975) is in the control column, and the results of the life table pairwise comparisons (Cox, 

Mean of all deaths (uncensored, censored, and terminal sacrifice) 

Kaplan-Meier determinations based on the number of animals alive on the first day of terminal sacrifice 

e Includes one animal that died during the last week of the study. 
58 Nickel Sulfate Hexahydrate, NTP TR 454 

1 .o 

0.9 

2 0.8 

2 

a 

> 

J 0.7 

0 

L 

v) 

g 

2 0.5 

E 0.6 

=! 

m 

a 0.4 

0.3 

0.2 

1.01 

0.9- 

> 5 0.7 

Q 

-I 0.8 

0 

L 

v) 

1 

E 0.6 

2 0.5 

m 

=! 

a 0.4 

0.3 

0.2 

I 1 I I I I 

15 30 45 60 75 90 T 105 

WEEKS ON STUDY 

.. 

n 0 YC/YX 

0 0. I2 uc/u3 

FEMALE RATS 

A 0.25 UC/U3 

I I I 8 

1s 30 45 60 75 90 105 

WEEKS ON STUDY 

Nickel Sulfate Hexahydrate by Inhalation for 2 Years 

Kaplan-Meier Survival Cutves for Male and Female Rats Administered 

FIGURE 2 

'0 

'0 
Results 59 

500 

450 

150 

I 

. -- I I I I I I I 

15 30 45 60 75 90 

WEEKS ON STUDY 

IO5 

500 

450 

I; 400 

Q 

rK 

Iz 350 

(3 

12 300 0 

I 

n 

3 

> 

p 250 

z 

w 

a 200 

1 50 

I00 

..... ....... 

........ 

l 0 YC/YJ 

0 0.5 UC/uJ 

A 0.25 uG/uJ 

0 0.12 W/u3 

I I I 

15 , 30 I 

45 I 

WEEKS ON SlUDY 

60 75 90 5 

by Inhalation for 2 Years 

Growth Curves for Male and Female Rats Administered Nickel Sulfate Hexahydrate 

FIGURE 3 
Nickel Sulfate Hexahydrate, NTP TR 454 

of Nickel Sulfate Hexahydrate 

Mean Body Weights and Survival of Male Rats in the 2-Year Inhalation Study 

TABLE 12 

Weeks 0 mdm3 

on Av. Wt. No. of Av. Wt. Wt. (% of No. of Av. Wt. Wt. (46 of No. of Av. Wt. Wt. (% of No. of 

study (8) Survivors (g) controls) Survivors (g) controls) Survivors (9) controls) Survivors 

0.12 me/mf 0.25 mg/m3 0.5 mg/m3 

101 

97 

93 

89 

85 

81 

77 

73 

69a 

65 

61 

57 

53 

49 

45 

41 

37 

33 

29a 

25 

21 

17 

13 

12 

11 

10 

9 

8 

7 

6 

5 

4 

3 

2 

1 

446 

452 

454 

469 

473 

48 1 

485 

487 

497 

495 

487 

487 

479 

467 

46 1 

45 1 

440 

435 

415 

405 

386 

36 1 

334 

325 

314 

303 

291 

284 

272 

256 

245 

230 

209 

183 

133 

Mean for weeks 

1-13 260 

14-52 425 

53-101 476 

21 

25 

32 

35 

41 

43 

47 

49 

51 

57 

57 

57 

57 

57 

57 

57 

58 

58 

58 

63 

63 

63 

64 

64 

64 

64 

64 

64 

64 

64 

64 

64 

64 

64 

64 

442 

448 

465 

466 

466 

474 

477 

480 

483 

482 

476 

475 

469' 

46 1 

453 

445 

435 

430 

408 

396 

373 

353 

324 

319 

305 

296 

284 

275 

268 

252 

238 

226 

205 

181 

132 

469 

417 

254 

99 

99 

103 

99 

99 

98 

98 

99 

97 

97 

98 

97 

98 

99 

98 

99 

99 

99 

98 

98 

97 

98 

97 

98 

97 

98 

98 

97 

98 

98 

97 

98 

98 

99 

99 

99 

98 

98 

22 

30 

33 

40 

44 

46 

51 

51 

51 

56 

56 

56 

56 

58 

58 

58 

58 

58 

58 

63 

63 

63 

63 

63 

63 

63 

63 

63 

63 

63 

63 

63 

63 

63 

63 

450 

455 

467 

470 

465 

476 

476 

473 

479 

480 

467 

472 

466 

456 

446 

438 

428 

418 

404 

393 

373 

350 

326 

318 

308 

297 

283 

277 

266 

252 

24 1 

225 

203 

177 

130 

469 

412 

254 

101 

101 

103 

100 

98 

99 

98 

97 

96 

97 

96 

97 

97 

98 

97 

97 

97 

96 

97 

97 

97 

97 

98 

98 

98 

98 

98 

98 

98 

98 

99 

98 

97 

97 

98 

99 

97 

98 

25 

30 

32 

34 

42 

43 

46 

49 

50 

56 

57 

57 

57 

57 

57 

57 

58 

58 

58 

63 

63 

63 

63 

63 

63 

63 

63 

63 

63 

63 

63 

63 

63 

63 

63 

438 

445 

455 

456 

465 

473 

47 1 

474 

475 

475 

463 

46 1 

457 

447 

441 

434 

426 

419 

403 

390 

373 

350 

331 

323 

313 

301 

289 

285 

273 

257 

247 

230 

208 

182 

132 

462 

409 

259 

98 

99 

100 

97 

98 

98 

97 

97 

96 

96 

95 

95 

95 

96 

96 

96 

97 

96 

97 

96 

97 

97 

99 

99 

100 

99 

100 

101 

100 

100 

101 

100 

100 

99 

100 

97 

96 

100 

23 

28 

32 

40 

41 

45 

48 

48 

48 

54 

55 

57 

57 

57 

58 

58 

58 

58 

58 

63 

63 

63 

63 

63 

63 

63 

63 

63 

63 

63 

63 

63 

63 

63 

63 

a Interim evaluations occurred during weeks 29 and 66. 
Results 61 

of Nickel Sulfate Hexahydrate 

Mean Body Weights and Survival of Female Rats in the 2-Year Inhalation Study 

TABLE 13 

Weeks 0 mdm’ 

on Av. Wt. No. of Av. Wt. Wt. (% of No. of Av. Wt. Wt. (Ti of No. of Av. Wt. Wt. (% of No. of 

Study (8) Survivors (8) controls) Survivors (g) controls) Survivors (g) controls) Survivors 

0.12 mglm’ 0.25 malm’ 0.5 malm’ 

101 

97 

93 

89 

85 

81 

77 

73 

69a 

65 

61 

57 

53 

49 

45 

41 

37 

33 

29a 

25 

21 

17 

13 

12 

11 

10 

9 

8 

7 

6 

5 

4 

3 

2 

1 

336 

334 

337 

338 

339 

333 

328 

326 

324 

318 

313 

306 

300 

288 

277 

267 

257 

249 

245 

237 

227 

214 

206 

203 

196 

191 

186 

182 

178 

171 

166 

159 

147 

136 

* 110 

326 

25 1 

1-13 172 

Mean for weeks 

53-101 

14-52 

26 

33 

38 

43 

45 

47 

49 

51 

52 

57 

58 

58 

58 

58 

58 

58 

58 

58 

58 

63 

63 

63 

63 

63 

63 

63 

63 

63 

63 

63 

63 

63 

63 

63 

63 

321 

326 

33 1 

321 

326 

323 

317 

315 

314 

3 10 

305 

297 

291 

28 1 

270 

259 

249 

243 

237 

230 

216 

208 

199 

198 

190 

188 

182 

176 

177 

168 

160 

157 

146 

135 

109 

316 

244 

168 

97 

98 

98 

97 

96 

97 

97 

97 

97 

97 

98 

97 

97 

98 

98 

97 

97 

98 

97 

97 

95 

97 

96 

98 

97 

98 

98 

97 

99 

98 

97 

99 

100 

99 

99 

97 

97 

98 

18 

21 

29 

35 

42 

45 

49 

51 

52 

57 

57 

57 

58 

58 

58 

58 

58 

58 

58 

63 

63 

63 

63 

63 

63 

63 

63 

63 

63 

63 

63 

63 

63 

63 

63 

327 

327 

32 1 

32 1 

318 

315 

311 

308 

307 

301 

296 

289 

282 

27 1 

262 

25 1 

243 

236 

232 

227 

216 

204 

198 

195 

190 

185 

178 

176 

172 

165 

162 

154 

143 

131 

109 

309 

238 

166 

97 

98 

95 

95 

94 

95 

95 

95 

95 

95 

95 

94 

94 

94 

95 

94 

95 

95 

95 

96 

95 

95 

96 

96 

97 

97 

96 

97 

97 

97 

97 

97 

98 

96 

99 

95 

95 

97 

31 

35 

42 

48 

51 

51 

51 

51 

52 

57 

57 

58 

58 

58 

58 

58 

58 

58 

58 

63 

63 

63 

63 

63 

63 

63 

63 

63 

63 

63 

63 

63 

63 

63 

63 

315 

3 10 

308 

311 

308 

309 

306 

302 

299 

297 

290 

283 

277 

266 

257 

249 

24 1 

235 

230 

224 

215 

204 

198 

192 

188 

183 

178 

176 

172 

165 

161 

153 

143 

131 

108 

301 

236 

165 

94 

93 

91 

92 

91 

93 

93 

93 

92 

93 

93 

93 

92 

93 

93 

93 

94 

94 

94 

94 

95 

95 

96 

95 

96 

95 

95 

97 

97 

97 

97 

96 

97 

96 

98 

92 

94 

96 

64 

64 

64 

64 

64 

64 

65 

65 

65 

65 

29 

34 

37 

39 

39 

40 

43 

45 

46 

53 

54 

54 

54 

55 

56 

56 

57 

57 

57 

63 

63 

64 

64 

64 

‘64 

a Interim evaluations occurred during weeks 29 and 66. 
62 Nickel Sulfate Hexahydrate, NTP TR 454 

female rats. 

in Appendix A for male rats and Appendix B for 

at least 5 % in at least one animal group are presented 

primary neoplasms that occurred with an incidence of 

animal tumor diagnoses, and statistical analyses of 

neoplasms and nonneoplastic lesions, individual 

node, and nose. Summaries of the incidences of 

nonneoplastic lesions of the lung, bronchial lymph 

biologically noteworthy changes in the incidences of 

This section describes the statistically significant or 

Pathology and Statistical Analyses 

consisted of multifocal, minimal to mild accumula0.25 or 0.5 mg/m3. Chronic active inflammation 

edly increased in male and female rats exposed to 

plasia, alveolar proteinosis, and fibrosis were markchronic active inflammation, macrophage hyperstudy (Tables 14, A5, and B5). The incidences of 

female rats at 7 and 15 months and at the end of the 

generally observed in 0.25 and 0.5 mg/m3 male and 

creased incidences of inflammatory lung lesions were 

of male or female rats (Tables 14, A3, and B3). Inno exposure-related neoplasms observed in the lung 

(Table F3) and 15 months (Table F4). There were 

icantly greater than those of the controls at 7 

0.5 mg/m3 males and females were generally signifLung: Absolute and relative lung weights of 

central lumens containing keratin. 

squamous epithelium without cellular atypia, and 

cysts had outer walls of well-differentiated, stratified 

well-differentiated squamous epithelium. Squamous 

characterized by replacement of pneumocytes by 

0.5 mg/m3 female rats. Squamous metaplasia was 

squamous cysts (2/54) occurred in the lungs of 

low columnar cells. Squamous metaplasia (4/54) and 

a discrete cluster of alveoli lined by low cuboidal or 

female rats. Focal alveolar epithelial hyperplasia was 

hyperplasia was slightly increased in 0.5 mg/m3 

tips of the lung lobes. Focal alveolar epithelial 

sclerotic areas either subjacent to the pleura or at the 

chyma and subjacent to the pleura and focal solid 

collagen involving alveolar septae within the parenFibrosis included increased connective tissue and 

aceous material within alveolar spaces (Plate 2). 

or globular homogeneous pale, acellular, proteinof minimal to mild amounts of eosinophilic granular 

pool of circulating monocytes. Proteinosis consisted 

these macrophages was probably the intravascular 

cytoplasm) within alveolar spaces. The source of 

phages (usually with abundant pale vacuolated 

minimal to mild severity and consisted of macrosurfaces (Plate 1). Macrophage hyperplasia was of 

within alveolar spaces, frequently subjacent to pleural 

tions of macrophages, neutrophils and cell debris 
Results 63 

of Nickel Sulfate Hexahydrate 

Incidences of Neoplasms and Nonneoplastic Lesions of the Lung of Rats in the 2-Year Inhalation Study 

TABLE 14 

0 mg/m3 0.12 mg/m3 . 0.25 mg/m3 0.5 mg/m3 

Lunga 

7-Month Interim Evaluation 

Male 

0 

0 

5 5 

15-Month Interim Evaluation 

Macrophage Hyperplasia 

Inflammation, Chronic Activeb 

Hyperplasia, Focal 

Fibrosis 

Alveolar Proteinosis 

Macrophage Hyperplasia 

Inflammation, Chronic Active 

Lung 

4* (1.O)C 

1 (1.0) 

0 

0 

0 

0 

0 

5 

0 

0 

0 

0 

1 (1.0) 

5 

Lung 

2-Year Study 

3 (1.0) 6 (1.2)

0 0 

7 (1.3) 9 (1.2)

14 (1.1) 11 (1.2) 

54 53 

Hyperplasia, Focal 2 

Fibrosis 

Alveolar Proteinosis 

Macrophage Hyperplasia 

Inflammation, Chronic Active 

Alveolarlbronchiolar Adenoma 

3 

or Carcinoma 1 0 

Squamous Cell Carcinoma or Alveolar/bronchi?lar Adenoma or Carcinomad 

Logistic regression testh 

First incidence (days) 

Terminal rateg 

Adjusted ratef 

Overall ratee 

P=O.249 P=0.236N 

733 (T) 

2/16 (13%) 0116 (0%) 

12.5% 0.0% 

2/54 (4%) 0/53 (0%) 

- 

1 

(continued) 

5** (1.0) 

4* (1.3) 

5 

1 

0 

1 (1.0) 

2 (1.0) 

1 (1.0) 

5 

35** (1.7) 

12** (1,4) 

35** (1.6) 

42** (1.9) 

53 

3 

1 

P=0.456N 

711 

0118 (0%) 

4.0% 

1/53 (2%) 

5** (2.0) 

5** (1.8) 

5 

0 

2 (1.0) 

4* (1.8) 

5** (2.0) 

5** (1.0) 

5 

2 

43** (1.8) 

41** (1.9) 

48** (2.2) 

46** (2.2) 

53 

3 

P=O.532 

628 

2/21 (10%) 

11.8% 

3/53 (6%) 
64 Nickel Sulfate Hexahydrate, NTP TR 454 

of Nickel Sulfate Hexahydrate (continued) 

Incidences of Neoplasms and Nonneoplastic Lesions of the Lung of Rats in the 2-Year Inhalation Study 

TABLE 14 

O mg/m3 0.12 mg/m3 0.25 mg/m3 0.5 mg/m3 

Female 

7-Month Interim Evaluation 

Alveolar Proteinosis 

Macrophage Hyperplasia 

Inflammation, Chronic Active 

Lung 

0 

0 

0 

5 

0 0 2 (1.0) 

2 (1.0) 4* (1.0) 5** (2.0) 

2 (1.0) 4* (1.3) 5** (2.0) 

5 5 5 

15-Month Interim Evaluation 

Hyperplasia, Focal 

Fibrosis 

Alveolar Proteinosis 

Macrophage Hyperplasia 

Inflammation, Chronic Active 

Lung 

1 0 0' 1 

0 0 1 (1.0) 3 (1.3) 

0 0 3 (1.3) 5** (1.4) 

1 (1.0) 1 (1.0) 3 (1.3) 5* (1.8) 

2 (1.0) 0 4 (1.0) 5 (1.2) 

5 5  

Lung 

2-Year Study 

0 0 4 

5 3 10 

8 (1.4) 7 (1.3) 45** (1.7) 49** (1.9) 

1 (1.0) 0 22** (1.5) 49** (2.6) 

9 (1.6) 10 (1.1) 32** (1.5) 45** (1.8) 

14 (1.4) 13 (1.2) 49** (2.1) 52** (2.3) 

52 53 53 

0 

Squamous Metaplasia 

Hyperplasia, Focal 

Fibrosis 

Alveolar Proteinosis 

Macrophage Hyperplasia 

Inflammation, Chronic Active 

Alveolar/bronchiolar Adenoma 0 

0 

7 

0 1 

** Significantly different (P10.01) from the control group by the Fisher exact test (interim evaluation) or the logistic regression test (2-year 

* Significantly different (P10.05) from the control group by the Fisher exact test 

(T)Terminal sacrifice 

a Number of animals with lung examined microscopically 

study) 

range 0% to 10% 

Historical incidence for 2-year inhalation studies with control groups (mean f standard deviation): 27/703 (3.8% f 3.8%); 

Average seventy grade of lesion in affected animals: 1 = minimal; 2 = mild; 3 = moderate; 4 = marked 

Number of animals with lesion 

prior to terminal kill as nonfatal. A lower incidence in an exposure group is indicated by N. 

the pairwise comparisons between the controls and that exposed group. The logistic regression test regards lesions in animals dying 

In the control column are the P values associated with the trend test. In the exposed group columns are the P values corresponding to 

Observed incidence in animals surviving until the end of the study 

Kaplan-Meier estimated neoplasm incidence at the end of the study after adjustment for intercurrent mortality 

e Number of animals with neoplasm per number of animals examined microscopically 

' Not applicable; no neoplasms in animal group 
Results 65 

Bronchial Lymph Node: Increased incidences of in the number of lymphocytes, primarily in the 

lymphoid hyperplasia in the bronchial lymph nodes paracortex, accompanied by an increase in the size of 

occurred in 0.5 mg/m3 male and female rats at the the lymph node. The lymphocytes were at different 

end of the 2-year study (Tables 15, A5, and B5). stages of differentiation, and overall architecture of 

Lymphoid hyperplasia consisted of a relative increase the lymph node was maintained. 

of Nickel Sulfate Hexahydrate 

Incidences of Nonneoplastic Lesions of the Bronchial Lymph Node of Rats in the 2-Year Inhalation Study 

TABLE 15 

0 mg/m3 0.12 mg/m3 0.25 mg/m3 0.5 mg/m3 

Male 

Lymphoid Hyperplasiab 

Bronchial Lymph Nodea 

7-Month Interim Evaluation 

Bronchial Lymph Node 

15-Month Interim Evaluation 

Lymphoid Hyperplasia 

Bronchial Lymph Node 

2-Year Study 

Lymphoid Hyperplasia 

Bronchial Lymph Node 

7-Month Interim Evaluation 

Lymphoid Hyperplasia 

Bronchial Lymph Node 

15-Month Interim Evaluation 

Lymphoid Hyperplasia 

Bronchial Lymph Node 

2-Year Study 

Lymphoid Hyperplasia 

0 

5 

0 

5 

0 

51 

5** (1.6)' 

5 

0 

5 

0 

49 

2 (1.0) 5** (1.6) 

5 5 

1 (1.0) 1 (1.0) 

5 4 

47 

3 (2.3) lo** (1.4) 

52 

1 (1.0) 4 (1.5) 4 (1.0) 

5 5 4 

0 

4 

0 

5 

0 

3 

50 52 

1 (2.0) 0 

51 

2 (1.5) 

4 (1.3) 

5 

5 

1 (1.0) 

11** (1.8) 

49 

a Number of animals with bronchial lymph node examined microscopically 

** Significantly different (PSO.01) from the control group by the Fisher exact test (interim evaluations) or the logistic regression test 

Average severity grade of lesion in affected animals: 1 = minimal; 2 = mild; 3 = moderate; 4 = marked 

Number of animals with lesion 

(2-year study) 
66 Nickel Sulfate Hexahydrate, NTP TR 454 

the number of cell layers of olfactory epithelial cells. 

was typically a minimal unilateral focal decrease in 

of the study (Tables 16, A5, and B5). This lesion 

significantly greater than those in controls at the end 

epithelium in 0.5 mg/m3 males and females were 

Nose: The incidences of atrophy of the olfactory 

0 mg/m3, 8/53; 0.12 mg/m3, 1/53; 0.25 mg/m3, 2/51; 

trends in all exposed groups of male rats [adenoma: 

bined) occurred with statistically significant negative 

adenoma and C-cell adenoma or carcinoma (comOther Organs: Incidences of thyroid gland C-cell 

8/5 1, 6/52; Table A5). 

slightly increased in all exposed groups (5153, 7/53, 

incidences of thyroid gland C-cell hyperplasia were 

8/53, 2/53, 2/5 1, 3/52; Table A3]. However, 

0.5 mg/m3, 1 /52; adenoma or carcinoma (combined) : 

historical controls in.2-year NTP inhalation studies. 

the incidences were within the 16% to 46% range of 

(22/53, 21/53, 11/53, 10154; Table B3). However, 

occurred with statistically significant negative trends 

noma, or carcinoma (combined) in female rats also 

Incidences of mammary gland fibroadenoma, adeof Nickel Sulfate Hexahydrate 

Incidences of Nonneoplastic Lesions of the Nose of Rats in the 2-Year Inhalation Study 

TABLE 16 

- 

O mg/m3 0.12 mg/m3 0.25 mglm3 0.5 mg/m3 

Male 

Nosea 

7-Month Interim Evaluation 

Atrophy, Olfactory Epitheliumb 

Nose 

2-Year Study 

Atrophy, Olfactory Epithelium 

Female 

Nose 

7-Month Interim Evaluation 

Atrophy, Olfactory Epithelium 

Nose 

15-Month Interim Evaluation 

Atrophy, Olfactory Epithelium 

Nose 

2-Year Study 

Atrophy, Olfactoly Epithelium 

0 

5 

0 

54 

0 

5 

0 

5 

0 

5 

0 

52 

0 

5 

0 

5 

5 

1 (l.O)C 1 (1.0) 

5 

53 53 

3 (1.0) 7** (1.0) 

0 

5 

0 

5 

1 (1.0) 

5 

5 

1 (1.0) 

0 

51 52 53 54 

1 (1.0) 1 (1.0) 7** (1.6) 

a Number of animals with nose examined microscopically 

** Significantly different (PSO.01) from the control group by the logistic regression test 

Average severity grade of lesion in affected animals: 1 = minimal; 2 = mild; 3 = moderate; 4 = marked 

Number of animals with lesion 
Results 67 

creasing exposure concentration. Additionally, the females at 15 months. 

and lung nickel burden values increased with in- weights of 0.5 mg/m3 lung burden study males and 

15-month interim evaluations (Tables 17 and H5), control at 7 months, as were the absolute lung 

were greater than those in the controls at the 7- and females was significantly greater than that of the 

Lung nickel burdens in exposed male and female rats absolute lung weight of 0.5 mg/m3 lung burden study 

llssue Burden Analyses 

Lung Weight and Lung Burden in Rats in the 2-Year Inhalation Study of Nickel Sulfate Hexahydratea 

TABLE 17 

Male 

7-Month Interim Evaluation 

n 

pg Ni/g control lung 

pg Ni/g lung 

pg Nillung 

Absolute lung wt (9) 

15-Month Interim Evaluation 

n 

pg Nilg control lung 

pg Nilg lung 

pg Nillung 

Absolute lung wt (g) 

Female 

7-Month Interim Evaluation 

n 

pg Nilg control lung 

pg Nilg lung 

pg Nillung 

Absolute lung wt (9) 

15-Month Interim Evaluation 

n 

pg Nilg control lung 

pg Nilg lung 

pg Nillung 

Absolute lung wt (g) 

1.64 f 0.09 

6 

- 

b 

- 

- 

4 

2.12 f 0.1oc 

- 

- 

- 

7. 

1.13 f 0.04 

- 

- 

- 

5 

1.37 f 0.07 - 

- 

- 

1.64 f 0.06 

7 

- 

- 

- 

5 

0.177 f 0.018* 

0.151 f 0.015* 

0.374 f 0.038* 

2.48 f 0.10 

7 

1.21 f 0.04 

- 

- 

- 

5 

1.58 f 0.13 

0.188 f 0.013** 

0.166 f 0.012** 

0.257 f 0.017** 

7 

1.61 f 0.05 

- 

- 

- 

5 

2.50 f a. 11 

0.528 f 0.061** 

0.448 f 0.049** 

1.117 f 0.128** 

1.10 f 0.03 

6 

- 

- 

- 

5 

1.49 0.04 

0.538 f 0.042** 

0,493 * 0.031** 

0.739 f 0.057** 

7 

1.77 f 0.07 

0.868 f 0.051** 

0.804 f 0.031** 

1.426 f 0.084** 

4 

1.688 f 0.257** 

1.268 f 0.205** 

3.575 f 0.545** 

3.00 f 0.26**‘ 

5 

1.176 f 0.084** 

0.996 f 0.071** 

1.326 f 0.095** 

1.33 f 0.04** 

5 

2.212 f 0.427** 

1.657 * 0.285** 

3.034 f 0.586** 

1.82 f 0.08** 

* Significantly different (PlO.05) from the control group by Williams’ or Dunnett’s test (lung weight) or Shirley’s test (lung burden 

b Results were below 0.282 (7 months) or 0.044 (15 months) (the limits of detection), or below the level of quantitation. 

a Mean f standard error; statistical tests were performed on unrounded data. 

** PlO.01 

parameters) 

n=5 
68 Nickel Sulfate Hexahydrate, NTF' TR 454 

16-D~y STUDY 

MICE 

the end of the study; all control and 3.5 mg/m3 mice 

All mice exposed to 7 mg/m3 or greater died before 

ated and lethargic and had rapid respiration rates. 

exposed to 7, 15, 30, or 60 mg/m3 appeared emacisurvived to the end of the study (Table 18). Mice 

TABLE 18 

Survival and Body Weights of Mice in the 16-Day Inhalation Study of Nickel Sulfate Hexahydrate 

Mean Bodv Weightb(& 

(%) 

Change Relative to Controls 

Final Weight 

Dose Survivala Initial Final 

(mg/m') 

Male 

60 

30 

15 

7 

3.5 

0 

Female 

60 

30 

15 

7 

3.5 

0 

0/5d 

015' 

019 

019 

515 

515 

015g 

0/5d 

015f 

015e 

515 

515 

22.2 f 0.3 

22.3 f 0.4 

21.9 f 0.3 

22.7 f 0.4 

22.2 f 0.3 

22.6 f 0.4 

18.4 f 0.3 

18.6 f 0.5 

18.7 f 0.6 

18.7 f 0.2 

18.8 f 0.2 

19.1 f 0.3 

22.9 f 0.2 

24.0 f 0.4 

- 

- 

- 

- 

20.2 f 0.3 

'19.5 f 0.7 - 

- 

- 

- 

0.7 f 0.2 

1.4 f 0.2 

- 

- 

- 

- 

0.7 * 0.5 

1.1 f 0.2 

- 

- 

- 

- 

Days of death: 1 on day 4, 4 on day 5 

Days of death: 2 on day 4, 3 on day 5 

Weights and weight changes are given as mean f standard error. 

a Number of animals surviving at 16 dayslnumber initially in group 

Days of death: 5 on day 5 

Days of death: 3 on day 5, 2 on day 6 

e Days of death: 1 on day 5, 4 on day 6 
Results 69 

mortality in the first week of the study, histo60 mg/m3 exposure groups. Because of the high 

male and female mice from the 7, 15, 30, and 

to the observation of diffusely reddened lungs in all 

necropsy, treatment-related gross lesions were limited 

significantly less than those of the controls. At 

weights of mice in all but the 3.5 mg/m3 groups were 

(Table F5). The absolute and relative thymus 

significantly greater than those of the controls 

female mice exposed to 7 mg/m3 or greater were 

Absolute and relative lung weights of male and 

of a few macrophages and neutrophils in the alveolar 

was a mild lesion that consisted of an accumulation 

mice. Inflammation in the lungs of 3.5 mg/m3 mice 

and macrophages occurred in the lungs of 7 mg/m3 

lar congestion, and cellular infiltrate of neutrophils 

necrotizing inflammatory lesions with edema, vascuoccurred in the lungs of all exposed mice. Diffuse, 

of male and female mice (Table 19). Inflammation 

pathologic lesions were present in the lung and nose 

7 mg/m3 exposure groups. Treatment-related histopathology evaluations were limited to the 0, 3.5, and 

of Nickel Sulfate Hexahydrate 

Incidences of Selected Nonneoplastic Lesions in Mice in the 16-Day Inhalation Study 

TABLE 19 

O mg/mg 3.5 mg/m3 7 mg/m3 

Male 

Lunga 

Inflammationb 

Lymph Node, Bronchial 

Hyperplasia 

Nose 

Olfactory Epithelium, Atrophy 

Female 

Lung 

Inflammation 

Lymph Node, Bronchial 

Hyperplasia 

Nose 

Olfactory Epithelium, Atrophy 

0 

5 

0 

4 

0 

5 

0 

5 

0 

2 

0 

5 

4* (2.3)C 

5 

0 

3 

5** (2.2) 

5 

5** (1.4) 

5 

1 (1.0) 

4 

5** (1.6) 

5 

5** (2.8) 

5 

0 

4 

0 

5 

5** (2.6) 

5 

0 

4 

0 

3 

a Number of animals with organ examined microscopically 

** P10.01 

* Significantly different (P10.05) from the control by the Fisher exact test 

Average severity of lesions in affected animals: 1 = minimal; 2 = mild; 3 = moderate; 4 = marked 

Number of animals with lesion 
70 Nickel Sulfate Hexahydrate, NTP TR 454 

spaces and alveolar septae. A moderate lymphoid ered to be nonspecific findings typically observed in 

spleen, thymus, and lymph nodes and were consid- lung of controls (Tables 20 and 11). 

males and females included lymphoid depletion in the 3.5 mg/m3 were significantly greater than those in the 

Other microscopic lesions observed in 3.5 mg/m3 Nickel concentrations in the lung of mice exposed to 

tory epithelium was present in all 3.5 mg/m3 mice. 

of one 3.5 mg/m3 male mouse. Atrophy of the olfac- moribund condition. 

\ hyperplasia was present in the bronchial ymph node mice that die early or are sacrificed because of a 

Lung Weight and Lung Burden in Mice in the 16-Day Inhalation Study of Nickel Sulfate Hexahydratea 

TABLE 20 

0 mg/m3 3.5 mg/m3 

n 5 5 

Male 

pg Nilg control lung 

pg Nilg lung 

pg Nillung 

Absolute lung wt (9) 0.144 f 0.006 - 

b 

- 

- 

Female 

pg Nilg control lung 

pg Nilg lung 

pg Nillung 

Absolute lung wt (g) 0.143 f 0.007 - 

- 

- 

4.620 f 0.609** 

3.020 f 0.437** 

0.664 f 0.090** 

0.221 f 0.012** 

4.980 f 1.324** 

3.540 f 0.493** 

0.712 f 0.080** 

0.206 f 0.015** 

a Mean f standard error; statistical tests were performed on unrounded data. 

** Significantly different (P50.01) from the control group by Williams’ test (lung weight) or Shirley’s test (lung burden parameters) 

Results were below 0.170 pg Ni (the limit of detection), or below the level of quantitation. 
Results 71 

to chemical exposure. 

controls. There were no clinical findings attributed 

exposed groups of mice were similar to those of the 

mean body weights and body weight gains of all 

survived to the end of the study (Table 21). Final 

0.12 mg/m3 male died before week 10; all other mice 

Four male and three female control mice and one 

13-WEEK STUDY 

groups. This could be related to the lymph node 

phocyte counts occurred in the 0.5 or 1 mg/m3 

the 0.5 or 1 mg/m3 female groups. Increased lymHowever, little or no inflammation was observed in 

presence of chronic active pulmonary inflammation. 

greater. This change could be consistent with the 

counts occurred in females exposed to 0.5 mg/m3 or 

numerous or severe. Increased segmented neutrophil 

(Table G3), although the changes in mice were not as 

reported for female rats occurred in female mice 

In general, hematology changes imilar to those 

exposed groups of males. 

No significant hematology changes occurred in the 

bin concentration occurred in 1 and 2 mg/m3 females. 

lymphocyte counts. A minimal increase in hemoglowere a reflection of the increased neutrophil and 

leukocyte counts in females exposed to 1 or 2 mg/m3 

tissue migration, and recirculation. Mild increases in 

as a result of altered cell margination or homing, 

creased cellular production, increases can also occur 

phil and lymphocyte counts can be related to in2 mg/m3 females. While elevated peripheral neutrohyperplasia observed, but the lesion only occurred in 

were observed (Table 52). 

vaginal cytology between exposed and control mice 

No significant differences in sperm morphology or 

cantly greater than those of the controls (Table F6). 

males and 2 mg/m3 males and females were signifiThe absolute and relative lung weights of 1 mg/m3 

Survival and Body Weights of Mice in the 13-Week Inhalation Study of Nickel Sulfate Hexahydrate 

TABLE 21 

Mean Body Weightb (e) 

(%) 

Change Relative to Controls 

Final Weight 

Dose Survivala Initial Final 

(mglm3) 

Male 

2 10/10 23.0 f 0.8 

1 10110 24.1 f 0.3 

0.5 10/10 23.2 f 0.6 

0.25 10110 24.9 f 0.3 

0.12 23.4 f 1.0 

0 24.1 f 0.5 

8/9d 

6/ 10' 

31.4 f 0.5 

31.9 f 0.7 

31.9 f 0.6 

30.6 f 0.5 

32.1 f 0.9 

30.7 f 0.5 

8.4 f 0.9 

7.8 f 0.8 

8.7 f 0.6 

5.7 f 0.6 

8.9 f 1.0 

7.2 f 0.5 

102 

104 

104 

100 

105 

Female 

2 10/10 

1 10/10 

0.5 10/10 

0.25 10/10 

0.12 10110 

0 71 1 Oe 

18.5 f 0.4 

18.9 0.4 

19.1 f 0.2 

19.1 f 0.6 

19.2 f 0.3 

17.8 f 0.7 

25.2 f 0.6 

26.6 f 0.5 

27.3 f 0.4 

27.0 f 0.6 

27.2 f 0.5 

25.9 f 0.8 

6.7 f 0.4 

7.7 f 0.6 

8.2 f 0.3 

7.9 f 0.9 

8.0 f 0.3 

7.1 f 0.8 

97 

103 

105 

104 

105 

a Number of animals surviving at 13 weekshumber initially in group 

Week of death: 10 

the study. Differences from the control group were not significant by Dunnett's test. 

Weights and weight changes are given as mean f standard error. Subsequent calculations are based on animals surviving to the end of 

e Weeks of death: 1, 3, 5 

' Week ofdeath: 5 
72 Nickel Sulfate Hexahydrate, NTP TR 454 

and seven male 2 mg/m3 mice. 

bronchial lymph nodes were enlarged in all female 

throughout the lung parenchyma. In addition, the 

foci, approximately 1 mm in diameter, scattered 

2 mg/m2 female mice, there were numerous white 

and bronchial lymph nodes of 2 mg/m3 mice. In five 

ment-related gross lesions were observed in the lungs 

lute or relative organ weights. At necropsy, treatThere were no other significant differences in absothe lesions were of minimal severity. Fibrosis was 

the number observed in 0.5 mg/m3 mice; however, 

in the lungs of 1 and 2 mg/m3 mice was greater than 

mice. The number of alveolar macrophages observed 

within the alveoli of 0.25 mg/m3 male and female 

minimal increase in the number of macrophages 

ity of inflammatory lesions in the lung. There was a 

exposure-related increase in the incidence and severof male and female mice (Table 22). There was an 

present in the lung, bronchial lymph nodes, and nose 

Treatment-related histopathologic lesions were 

nickel sulfate hexahydrate. 

observed in mice exposed to 0.12 or 0.25 mg/m3 

No treatment-related histopathologic changes were 

evident in the dorsal meatus of the nasal passages. 

epithelial layer. The olfactory lesion was most 

mice and consisted of a slight thinning of this neuroin the highest exposure groups of male and female 

atrophy of the olfactory epithelium was present only 

cortical region of the lymph nodes. A minimal 

an increase in lymphocytes, primarily in the paraenlargement of these lymph nodes. This consisted of 

chial lymph nodes, which corresponded to the gross 

Microscopically, there was hyperplasia in the bronvessels were also present in male and female mice. 

trates of lymphocytes and macrophages around blood 

inflammation without fibrosis and interstitial infilof fibroblasts. Scattered foci of chronic alveolar 

matory cell infiltrate and an increase in the number 

the alveolar septae, resulting from a chronic inflamthe lesion was characterized by a focal thickening of 

present in most 2 mg/m3 male and female mice, and 
Results 73 

of Nickel Sulfate Hexahydrate 

Incidences of Selected Nonneoplastic Lesions in Mice in the 13-Week Inhalation Study 

TABLE 22 

0 mg/m3 0.12 mg/m3 0.25 mg/m3 0.5 mg/m3 1 mg/m3 2 mgh3 

Lunga 

Male 

Alveolar Macrophage, 

6 

Fibrosis 0 

Inflammation, Chronic Active 0 

Interstitial Infiitrate 0 

0 

0 

2 

9 

0 

0 

0 

Hyperplasiab 0 

Lymph Node, Bronchial d 

Hyperplasia 

- 

Nose 

Olfactory Epithelium, Atrophy 0 

6 

0 

9 

Female 

Lung 

Alveolar Macrophage, 

7 10 

Fibrosis 0 0 

Inflammation, Chronic Active 0 0 

Interstitial Illfiitrate 1 (1.0) 0 

Hyperplasia 0 0 

Lymph Node, Bronchial 

0 

4 - 

Hyperplasia 

Nose 

Olfactory Epithelium, Atrophy 0 

7 

0 

10 

10 

0 

10 

10 

0 

10 

10 10 

2 (1.0) 

2 (1.0) 

lo** (1.O)C lo** (1.0) 

0 

0 

0 

0 

6 

2 (1.5) 

- 

0 

10 

0 

to 

10 10 

lo** (1.0) lo** (1.0) 

1 (1.0) 1 (1.0) 

0 1 (1.0) 

0 1 (1.0) 

- 

0 

7 

0 

10 

0 

10 

10 

lo** (2.0) 

2 (1.5) 

8** (1.0) 

lo** (1 .O) 

5 (1.0) 

8 

lo** (1.0) 

10 

10 

8** (1.5) 

9** (1.9) 

8* (1.3) 

lo** (1 .O) 

10 

8* (1.1) 

5* (1.0) 

10 

a Number of animals with organ examined microscopically 

** P40.01 

* Significantly different (P 50.05) from the control group by the Fisher exact test 

Organ not examined at this exposure concentration. 

Average severity of lesions in affected animals: 1 = minimal; 2 = mild; 3 = moderate; 4 = marked 

Number of animals with lesion 
74 Nickel Sulfate Hexahydrate, NTP TR 454 

exposed to 2 mg/m3 was significantly greater than and 12). 

The nickel concentration in the lung of feamles that in he lung of control animals (Tables 23 

Lung Weight and Lung Burden in Mice in the 13-Week Inhalation Study of Nickel Sulfate Hexahydratea 

TABLE 23 

0 mg/m3 0.12 mg/m3 0.5 mg/m3 2 mg/m3 

Male 

n 

pg Nilg control lung 

pg Nilg lung 

pg Ninung 

Absolute lung wt (g) 

Female 

n 

pg Nilg control lung 

pg Ni/g lung 

pg Nillung 

Absolute lung wt (g) 

0.183 f 0.008 

5 

- b 

5 

0.157 f 0.009 - 

- 

- 

6 

0.166 f 0.011 - 

- 

- 

6 

0.149 f 0.007 - 

- 

- 

6 

0.175 f 0.002 - 

- 

- 

5 

0.156 f 0.008 - 

- 

- 

6 

1.275 f 0.807 

0.790 f 0.503 

0.234 f 0.148 

0.300 f 0.014** 

6 

4.008 f 0.804** 

2.205 f 0.444** 

0.630 f 0.126** 

0.279 f 0.008** 

b Results were below 0.228 pg Ni (the limit of detection) or below the level of quantitation. 

a Mean f standard error; statistical tests were performed on unrounded data. 

** Significantly different (PSO.01) from the control group by Williams’ test (lung weight) or Dunn’s or Shirley’s test (lung burden 

parameters) 

Dose Selection Rationale: Based on the lung weight hydrate xposure concentrations elected for the 

increases and increased incidences of lung lesions in 2-year inhalation study in mice were 0.25, 0.5, and 

2 mg/m3 males and females, nickel sulfate hexa- 1 mg/m3. 
Results 75 

females were similar to those of the controls. 

survival rates of all exposed groups of males and 

Kaplan-Meier survival curves (Figure 4). The 

and female mice are shown in Table 24 and in the 

Estimates of 2-year survival probabilities for male 

Survival 

%YEAR STUDY 

administration. 

clinical findings considered related to chemical 

(Figure 5 and Tables 25 and 26). Mice exhibited no 

the controls during the second year of the study 

exposed groups of females were lower than those of 

The mean body weights of 1 mg/m3 males and of all 

Body Weights and Clinical Findings 

Survival of Mice in the 2-Year Inhalation Study of Nickel Sulfate Hexahydrate 

TABLE 24 

0 mg/m3 0.25 mg/m3 0.5 mg/m3 1 mg/m3 

7-Month interim evaluationa 

Animals initially in study 

Male 

Mean survival (days)' 

Percent probability of survival at end of studyb 

Animals surviving to study termination 

Natural deaths 

Moribund kills 

15-Month interim evaluationa 

7-Month interim evaluationa 

Animals initially in study 

Female 

Survival analysisd 

Mean survival (days) 

Percent probability of survival at end of study 

Animals surviving to study termination 

Natural deaths 

Moribund kills 

15-Month interim evaluationa 

Survival analysis 

71 71 72 72 

5 5 5 5 

5 5 5 5 

30 29 29 27 

5 9 9 10 

26 23 24 25 

43 38 40 42 

647 634 637 650 

P=0.890N P=O.657 P=O.877 P=1.000N 

71 

673 

57 

34e 

7 

20 

5 

5 

70 

674 

65 

39a 

10 

11 

5 

5 

70 

697 

75 

45 

4 

11 

5 

5 

70 

662 

62 

37 

6 

17 

5 

5 

P=0.791N P=0.494N P=0.062N P=0.843N 

a Censored from survival analyses 

1972) with the controls are in the dosed columns. A negative trend or a lower mortality in a dose group is indicated by N. 

The result of the life table trend test (Tarone, 1975) is in the control column, and the results of the life table pairwise comparisons (Cox, 

Mean of all deaths (uncensored, censored, and terminal sacrifice) 

Kaplan-Meier determinations based on the number of animals alive on the first day of terminal sacrifice 

e Includes one animal that died during the last week of the study. 
76 Nickel Sulfate Hexahydrate, NTP TR 454 

1.01 

0.9. 

-4 

k 

2 

5 0.1 

3 * 0.7 

=! 0.6 

t 

* 

a 0.5 

6 

m 

m 

$i 

0.4 

0.3 

1 .O 

0.9 

i= 

a 0.5 

m 

m 

6 

2 0.6 

0.4 

0.: 

............ 

... 

.. 

... 

I 

I I I I 

15 30 45 60 75 90 105 

WEEKS ON STUDY 

-I 

12 

..... 

k' ......... 

.. 

..... 

I I I I 1 I I 

WEEKS ON STUDY 

15 30 45 60 75 90 1 05 

!O 

Nickel Sulfate Hexahydrate by Inhalation for 2 Years 

Kaplan-Meier Survival Curves for Male and Female Mice Administered 

FIGURE 4 
Results 77 

W 

a 

I 

20 

I5 

f 

..... I 

-1 I 

0 

I I 1 I 

I5 30 45 60 75 90 

WEEKS ON STUDY 

45 , 

.................................. 

....... 

& 0.5 W;/bi3 

0 0.25 YC/Y3 

I5 

0 I I 1 I I I IS so 45 60 

WEEKS ON STUDY 

75 90 

by Inhalation for 2 Years 

Growth Curves for Male and Female Mice Administered Nickel Sulfate Hexahydrate 

FIGURE 5 
Nickel Sulfate Hexahydrate, NTP TR 454 

of Nickel Sulfate Hexahydrate 

Mean Body Weights and Survival of Male Mice in the 2-Year Inhalation Study 

TABLE 25 

Weeks 0 mdm3 

on Av. Wt. No. of Av. Wt. Wt. (% of No. of Av. Wt. Wt. (% of No. of Av. Wt. Wt. (% of No. of 

Study (9) Survivors (9) controls) Survivors (g) controls) Survivors (9) controls) Survivors 

0.25 mg/m' 0.5 mg/m3 1 mg/m3 

33a 

29 

25 

21 

17 

13 

12 

11 

10 

9 

8 

7 

6 

5 

4 

3 

2 

1 

101 

97 

93 

89 

85 

81 

77 

73 

69a 

65 

61 

57 

53 

49 

45 

41 

' 37 

40.2 

40.3 

40.9 

41.6 

42 .O 

41.8 

43.1 

43.4 

43.9 

43.5 

43.2 

42.6 

42.4 

41.4 

40.9 

40.5 

39.6 

38.7 

37.9 

36.0 

35.1 

34.0 

32.8 

32.4 

32.4 

31.8 

31.4 

31.2 

30.5 

30.1 

29.2 

28.6 

27.6 

26.1 

23.5 

Mean for weeks 

53-101 42.2 

14-52 

1-13 

38.2 

29.8 

27 

29 

31 

35 

45 

51 

54 

57 

57 

66 

67 

67 

68 

68 

68 

69 

69 

70 

80 

80 

80 

80 

80 

80 

80 

80 

80 

80 

80 

80 

80 

80 

80 

80 

80 

37.9 

38.4 

39.0 

40.0 

40.4 

41.0 

41.3 

41.9 

42.5 

42.2 

42.7 

41.5 

41.2 

40.3 

39.4 

39.2 

38.6 

38.3 

37.2 

35.6 

34.7 

33.7 

33.0 

32.2 

31.8 

31.7 

31.2 

30.6 

30.5 

30.0 

29.2 

28.4. 

27.2 

25.7 

23.2 

40.8 

37.4 

29.6 

94 

95 

95 

96 

96 

98 

96 

97 

97 

97 

99 

97 

97 

97 

96 

97 

98 

99 

98 

99 

99 

99 

101 

99 

98 

100 

99 

98 

100 

100 

100 

99 

99 

99 

99 

97 

98 

99 

26 

29 

32 

36 

38 

45 

51 

54 

55 

65 

66 

67 

67 

67 

68 

69 

69 

69 

78 

78 

78 

80 

80 

80 

80 

80 

80 

80 

80 

80 

80 

80 

80 

80 

80 

39.1 

38.8 

39.8 

39.6 

40.6 

41.1 

40.7 

42.0 

42.4 

42.1 

42.6 

41.5 

41.4 

40.3 

39.5 

38.8 

38.7 

38.0 

36.9 

35.4 

35.0 

33.8 

32.8 

32.4 

32.2 

31.8 

31.3 

30.6 

30.2 

29.8 

29.1 

28.5 

27.4 

26.2 

23.2 

40.9 

37.4 

29.7 

97 

96 

97 

95 

97 

98 

94 

97 

97 

97 

99 

97 

98 

97 

97 

96 

98 

98 

97 

98 

100 

99 

100 

100 

99 

100 

100 

98 

99 

99 

100 

100 

99 

100 

99 

97 

98 

100 

26 

30 

31 

38 

42 

46 

50 

53 

55 

64 

64 

65 

66 

66 

67 

68 

69 

70 

80 

80 

80 

80 

80 

80 

80 

80 

80 

80 

80 

80 

80 

80 

80 

80 

80 

36.7 

36.6 

37.6 

37.5 

39.6 

39.9 

40.7 

40.5 

41.3 

41.5 

42.1 

40.6 

40.8 

39.9 

39.1 

38.7 

38.5 

38.1 

36.9 

35.5 

34.6 

33.5 

32.8 

32.3 

32.0 

31.8 

31.2 

30.9 

30.4 

29.9 

29.2 

28.5 

27.4 

25.9 

23.1 

39.7 

31.2 

29.7 

91 

91 

92 

90 

94 

96 

94 

93 

94 

95 

98 

95 

96 

96 

96 

96 

97 

98 

97 

99 

99 

99 

100 

100 

99 

100 

99 

99 

100 

99 

100 

100 

99 

99 

98 

94 

97 

100 

27 

30 

35 

40 

47 

51 

52 

55 

56 

65 

66 

67 

68 

68 

69 

69 

69 

69 

79 

79 

80 

80 

80 

80 

80 

80 

80 

80 

80 

80 

80 

80 

80 

80 

80 

a Interim evaluations occurred during weeks 30 and 66. 
Results 79 

TABLE 26 

of Nickel Sulfate Hexahydrate 

Mean Body Weights and Survival of Female Mice in the 2-Year Inhalation Study 

Weeks 0 me/m3 

on Av. Wt. No. of Av. Wt. Wt. (% of No. of Av. Wt. Wt. (56 of No. of Av. Wt. Wt. (5% of No. of 

Study (9) Survivors (9) controls) Survivors (8) controls) Survivors (9) controls) Survivors 

0.25 mdm3 0.5 meh3 1 mdm’ 

101 

97 

93 

89 

85 

81 

77 

73 

69a 

65 

61 

57 

53 

49 

45 

41 

37 

33a 

29 

25 

21 

17 

13 

12 

11 

10 

9 

8 

7 

6 

5 

4 

3 

2 

1 

37.7 

38.7 

39.6 

40.2 

41.8 

41.6 

42.1 

42.5 

42.6 

42.3 

42 .O 

40.3 

40.3 

39.1 

38.5 

37.7 

37.2 

35.7 

34.2 

32.3 

31.4 

29.8 

28.3 

27.5 

27.5 

27 .O 

26.5 

26.3 

25.8 

25.2 

23.8 

23.1 

22.5 

20.9 

19.2 

Mean for weeks 

53-101 40.9 

14-52 

1-13 

35.1 

24.9 

40 

43 

46 

50 

52 

53 

54 

55 

55 

65 

66 

67 

68 

68 

69 

69 

69 

70 

79 

79 

79 

79 

79 

79 

79 

79 

79 

79 

79 

79 

80 

80 

80 

80 

80 

34.3 

35.0 

35.4 

36.0 

37.6 

37.7 

38.6 

39.1 

40.9 

40.6 

40.8 

39.4 

38.5 

37.8 

36.1 

36.6 

35.9 

34.9 

33.7 

32.1 

30.6 

29.5 

28.3 

27.1 

26.7 

27.0 

26.3 

25.8 

25.5 

25.1 

24.2 

23.1 

21.9 

20.6 

18.9 

38.0 

34.1 

24.7 

91 

90 

89 

90 

90 

91 

92 

92 

96 

$96 

97 

98 

96 

97 

94 

97 

97 

98 

99 

99 

98 

99 

100 

99 

97 

100 

99 

98 

99 

100 

102 

100 

97 

99 

98 

93 

97 

99 

42 

45 

47 

50 

51 

53 

54 

55 

56 

66 

66 

66 

68 

69 

69 

69 

69 

69 

79 

79 

79 

79 

79 

79 

79 

79 

79 

79 

79 

79 

79 

79 

79 

80 

80 

35.5 

35.5 

36.1 

36.4 

37.4 

38.3 

38.1 

39.1 

39.9 

40.3 

40.2 

39.3 

38.4 

37.9 

36.8 

35.8 

35.9 

35.2 

33.6 

31.9 

31.2 

29.6 

28.2 

27.7 

27.4 

27.3 

26.5 

26.1 

25.6 

24.9 

24.2 

23.7 

22.6 

20.9 

18.8 

38 .O 

34.2 

24.9 

94 

92 

91 

91 

90 

92 

91 

92 

94 

95 

96 

98 

95 

97 

96 

95 

97 

99 

98 

99 

99 

99 

100 

101 

100 

101 

100 

99 

99 

99 

102 

103 

100 

100 

98 

93 

97 

100 

46 

48 

51 

53 

54 

56 

57 

57 

58 

69 

69 

69 

69 

69 

70 

70 

70 

70 

80 

80 

80 

80 

80 

80 

80 

80 

80 

80 

80 

80 

80 

80 

80 

80 

80 

33.2 

33.2 

33.8 

33.3 

35.1 

35.8 

36.5 

37.0 

37.6 

37.4 

38.1 

37.5 

36.4 

35.8 

35.4 

34.9 

34.9 

34.0 

33.0 

31.3 

30.1 

29.1 

28.1 

27.5 

27.2 

27.0 

26.2 

26.1 

25.7 

24.9 

23.9 

23.4 

22.4 

20.7 

18.9 

35.8 

33.2 

24.8 

88 

86 

85 

83 

84 

86 

87 

87 

88 

88 

91 

93 

90 

92 

92 

93 

94 

95 

97 

97 

96 

98 

99 

100 

99 

100 

99 

99 

100 

99 

100 

101 

100 

99 

98 

88 

95 

99 

40 

42 

45 

45 

48 

49 

51 

53 

53 

65 

65 

65 

67 

68 

68 

69 

70 

70 

80 

80 

80 

80 

80 

80 

80 

80 

80 

80 

80 

80 

80 

80 

80 

80 

80 

a Interim evaluations occurred during weeks 30 and 66. 
80 Nickel Sulfate Hexahydrate, NTP TR 454 

Hematology olar epithelial hyperplasia), alveolar proteinosis, and 

No biologically significant hematology differences infiltrating cells in the interstitium. Macrophage 

occurred in male or female mice (Table G4). hyperplasia was the most commonly diagnosed lesion 

in the lungs and consisted of scattered enlarged 

and Appendix D for female mice. 

section are presented in Appendix C for male mice 

ical incidences for the neoplasms mentioned in this 

at least 5% in at least one animal group, and historprimary neoplasms that occurred with an incidence of 

animal tumor diagnoses, and statistical analyses of 

neoplasms and nonneoplastic lesions, individual 

node, and nose. Summaries of the incidences of 

nonneoplastic lesions of the lung, bronchial lymph 

biologically noteworthy changes in the incidences of 

This section describes the statistically significant or 

Pathology and Statistical Analyses 

chronic active inflammation, bronchialization (alveThese lesions included macrophage hyperplasia, 

end of the 2-year study (Tables 27,' C5, and D5). 

female mice and in the 0.5 and 1 mg/m3 males at the 

lesions of the lung occurred in all exposed groups of 

groups of mice. Treatment-related inflammatory 

plasia or in the incidence of neoplasms in exposed 

(Table F8). There was no increase in focal hyperthe controls at the 15-month interim evaluation 

and females were significantly greater than those of 

Lung: The absolute lung weights of 1 mg/m3 males 

perivascular and peribronchiolar connective tissue. 

lymphocytes with fewer macrophages primarily in the 

Infitrating cells in the interstitium were primarily 

material within a variable number of alveolar spaces. 

was an eosinophilic, acellular, granular or hyaline 

microscopic appearance only. Alveolar proteinosis 

ization in this study -corresponds to the overall light 

determine their cell of origin, the term bronchialobserved to have cilia and no attempts were made to 

than normal. Because these cuboidal cells were not 

bronchiole extends farther. into the peripheral lung 

it appeared as though the epithelial lining of the 

into the alveolar ducts and proximal alveoli, because 

epithelial cells extended from the terminal bronchiole 

defined as hyperplastic and/or hypertrophic cuboidal 

lations. In the present study, bronchialization was 

septae adjacent to these inflammatory cell accumuoften was minimal to mild septal fibrosis in alveolar 

eosinophilic rystalline material (Plate 3). There 

sometimes mixed with cell debris and/or brightly 

tions of macrophages, neutrophils, and lymphocytes 

inflammation consisted of intra-alveolar accumulapool of circulating monocytes. Chronic active 

these macrophages was probably the intravascular 

macrophages within alveolar spaces. The source of 
Results 81 

of Nickel Sulfate Hexahydrate 

Incidences of Neoplasms and Nonneoplastic Lesions of the Lung of Mice in the 2-Year Inhalation Study 

TABLE 27 

0 mg/m3 0.25 mg/m3 0.5 mg/m3 1 mg/m3 

Male 

Lunga 

7-Month Interim Evaluation 

0 

0 

0 

0 

5 

Alveolar Proteinosis 

Interstitial Infiltration 

Macrophage Hyperplasia 

Inflammation, Chronic Activeb 

15-Month Interim Evaluation 

Alveolar Proteinosis 

Interstitial Infiltration 

Macrophage Hyperplasia 

Bronchialization 

Inflammation, Chronic Active 

Lung 

0 

0 

0 

0 

0 

5 

Lung 

2-Year Study 

61 

Inflammation, Chronic Active 1 (2.0) 

Bronchialization 1 (1.0) 

Macrophage Hyperplasia 6 (2.8) 

Interstitial Infilmtion 1 (3.0) 

Alveolar Proteinosis 0 

Alveolar Epithelial Hyperplasia, Focal 0 

Alveolar/bronchiolar Adenoma 5 

Alveolar/bronchiolar Adenoma or Carcinomad 

Alveoladbronchiolar Carcinoma 9 

Logistic regression test" 

First incidence (days) 

Terminal rateg 

Adjusted ratef 

Overall ratee 

P=0.029N 

516 

10126 (38 X) 

43.6% 

13/61 (21%) 

0 

0 

1 (1.0) 

1 (1.0) 

0 

5 

0 

0 

0 

9 (1.4) 

4 (1.5) 

2 (1.0) 

61 

5 

13 

P=O.144 

552 

14/23 (61 %) 

65.4% 

18/61 (30%) 

0 

0 

0 

5 

1 (1.OY 

0 

0 

4* (1.0) 

0 

0 

5 

0 

0 

3 (1.3) 

35** (1.5) 

19** (1.1) 

8* (1.5) 

62 

3 

4 

P=O.lllN 

552 

3/24 (13%) 

21.2% 

7/62 (1 1 X) 

0 

1 (1.0) 

5** (1.0) 

0 

5 

3 (1.0) 

5** (1.0) 

5** (1.0) 

5** (1.0) 

4* (1.3) 

5 

61 . 

0 

42** (2.0) 

17** (1.2) 

59** (2.1) 

39** (1.1) 

29** (1.9) 

5 

3 

P=0.142N 

561 

5/25 (20%) 

26.2% 

8/61 (13%) 

(continued) 
82 Nickel Sulfate Hexahydrate, NTP TR 454 

of Nickel Sulfate Hexahydrate (continued) 

Incidences of Neoplasms and Nonneoplastic Lesions of the Lung of Mice in the %Year Inhalation Study 

TABLE 27 

O mg/m3 0.25 mg/m3 0.5 mg/m3 1 mg/m3 

7-Month Interim Evaluation 

Female 

Alveolar Proteinosis 

Interstitial Infiltration 

Macrophage Hyperplasia 

Inflammation, Chronic Active 

Lung 

0 

0 

0 

0 

5 

0 0 

0 1 (2.0) 

1 (1.0) 5** (1.0) 

0 2 (1.0) 

5 5 

15-Month Interim Evaluation 

Alveolar Proteinosis 

Interstitial Infiltration 

Macrophage Hyperplasia 

Bronchialization 

Inflammation, Chronic Active 

Lung 

0 0 0 5** (1.2) 

1 (1.0) 0 0 5* (1.2) 

0 1 (1.0) 2 (1.0) 5** (1.2) 

0 0 1 (1.0) 5** (1 .O) 

0 0 0 5** (1.2) 

5 5 5 5 

Lung 

2-Year Study 

Alveolar Epithelial Hyperplasia, Focal 0 1 (2.0) 1 (2.0) 

Alveolar Proteinosis 0 0 11** (1.4) 45** (1.9) 

Interstitial Infiltration 0 4 (2.0) 16** (1.1) 39** (1.4) 

Macrophage Hyperplasia 7 (1.6) 24** (1.3) 53** (1.5) 59** (2.4) 

Bronchialization 0 9** (1.0) 32** (1.0) 45** (1.1) 

Inflammation, Chronic Active 1 (1.0) 7* (1.3) 14**(1.1) 40** (1.6) 

61 60 60 60 

0 

Alveolar/bronchiolar Adenoma 3 3 2 0 

Alveolar/bronchiolar Adenoma or Carcinoma’ 

Alveolar/bronchiolar Carcinoma 4 3 9 2 

Logistic regression test 

First incidence (days) 

Terminal rate 

Adjusted rate 

Overall rate 7/61 (1 1 %) 6/60 (10%) 10/60 (17%) 2/60 (3 %) 

19.3% 13.9% 21.1% 4.3% 

6/34 (18%) 3/39 (8 %) 8/45 (18%) 0137 (0%) 

627 649 656 562 

P=O.lllN P=0.481N P=O.371 P=0.088N 

* Significantly different (P 50.05) from the control group by the Fisher exact test (interim evaluations) or the logistic regression test 

’ Number of animals with lesion 

a Number of animals with lung examined microscopically 

** P50.01 

(2-year study) 

range 10% to 42% 

Historical incidence for 2-year inhalation studies with control groups (mean f standard deviation): 2051952 (21.5% f 8.0%); 

Average severity grade of lesion in affected animals: 1 = minimal; 2 = mild; 3 = moderate; 4 = marked 

Observed incidence in animals surviving until the end of the study 

Kaplan-Meier estimated neoplasm incidence at the end of the study after adjustment for intercurrent mortality 

prior to terminal kill as nonfatal. A negative trend or a lower incidence in an exposure group is indicated by N. 

the painvise comparisons between the controls and that exposed group. The logistic regression test regards lesions in animals dying 

’ In the control column are the P values associated with the trend test. In the exposed group columns are the P values corresponding to 

e Number of animals with neoplasm per number of animals examined microscopically 

’ Historical incidence: 97/944 (10.3% f 3.7%);.range, 0% to 16% 
Results 83 

hypertrophic macrophages within the lymph node. 

consisted of scattered clusters of a few to several 

(Tables 28, C5, and D5). Macrophage hyperplasia 

0.5 mg/m3 females at the end of the 2-year study 

the 1 mg/m3 males and females and in some 

occurred in the bronchial lymph nodes of most of 

hyperplasia and/or lymphoid hyperplasia 

Bronchial Lymph Node: Incidences of macrophage 

ture . 

of the lymph node without distortion of its architecdifferentiation that resulted in variable enlargement 

and/or paracortical lymphocytes in various stages of 

hyperplasia was an increased number of cortical 

matory alterations in the lungs. Lymphoid 

bronchial lymph node are consistent with the inflamThe increased numbers of macrophages within the 

of Nickel Sulfate Hexahydrate 

Incidences of Nonneoplastic Lesions of the Bronchial Lymph Node of Mice in the 2-Year Inhalation Study 

TABLE 28 

0 mg/m3 0.25 mg/mg 0.5 mg/m3 1 mg/m3 

Male 

7-Month Interim Evaluation 

Macrophage Hyperplasia 

Lymphoid Hyperplasiab 

Bronchial Lymph Nodea 5 

1 (1.O)C 

0 

1 (1.0) 

3 

0 

1 (1.0) 

2 

0 

0 

5 

0 

Bronchial Lymph Node 

15-Month Interim Evaluation 

Macrophage Hyperplasia 

Lymphoid Hyperplasia 

0 

3 (1.3) 

5 

0 

1 (1.0) 

5 

4 (1.0) 

0 

4 5 

1 (1.0) 

1 (1.0) 

Bronchial Lymph Node 

2-Year Study 

Macrophage Hyperplasia 

Lymphoid Hyperplasia 

0 

2 (1.5) 

46 

0 

4 (1.5) 

49 45 

8** (1.1) 

2 (2.0) 

39** (1.4) 

17** (1.6) 

54 

Female 

Bronchial Lymph Node 

7-Month Interim Evaluation 

Macrophage Hyperplasia 

Lymphoid Hyperplasia 

5 

2 (1.0) 

0 0 

2 (1.0) 

4 

0 

1 (1.0) 

4 

0 

3 (1.7) 

4 

Bronchial Lymph Node 

15-Month Interim Evaluation 

Macrophage Hyperplasia 

Lymphoid Hyperplasia 

Bronchial Lymph Node 

2-Year Study 

Macrophage Hyperplasia 

Lymphoid Hyperplasia 

0 

0 

2 

0 

1 (1.0) 

5 5 

2 (1.0) 

0 4 (1.0) 

4 (1.5) 

4 

2 (1.0) 

15 (1.8) 

50 54 

0 

9 (1.8) 

14* (1.1) 

16 (1.6) 

58 

37** (1.5) 

26* (2.0) 

56 

a Number of animals with bronchial lymph node examined microscopically 

** PSO.01 

* Significantly different (P10.05) from the control group by the logistic regression test 

Average severity grade of lesion in affected animals: 1 = minimal: 2 = mild; 3 = moderate; 4 = marked 

Number of animals with lesion 
84 Nickel Sulfate Hexahydrate, NTP TR 454 

Nose: Atrophy of the olfactory epithelium was were significantly greater than those in the controls 

observed in 0.5 and 1 mg/m3 males and in all groups at the end of the study. Typically, this lesion was a 

of females at the end of the 2-year study (Tables 29, minimal focal decrease in the number of olfactory 

C5, and D5). The incidences of this lesion in cells resulting in a thinning of the affected portion of 

1 mg/m3 males and females and in 0.5 mg/m3 males the epithelium (Plate 4). 

of Nickel Sulfate Hexahydrate 

Incidences of Nonneoplastic Lesions of the Nose of Mice in the 2-Year Inhalation Study 

TABLE 29 

0 mg/m3 0.25 mg/m3 0.5 mg/m3 1 mg/m3 

Male 

Nosea 

7-Month Interim Evaluation 

Atrophy, Olfactory Epithelium 

Nose 

15-Month Interim Evaluation 

Atrophy, Olfactory Epitheliumb 

Nose 

2-Year Study 

Atrophy, Olfactory Epithelium 

Female 

Nose 

7-Month Interim Evaluation 

Atrophy, Olfactory Epithelium 

Atrophy, Olfactory Epithelium 

Nose 

15-Month Interim Evaluation 

Nose 

2-Year Study 

Atrophy, Olfactory Epithelium 

0 

5 

0 

5 

0 

61 

0 

5 

0 

5 

0 

5 

0 

5 

0 

61 

0 

5 

0 

5 

0 

5 5 

2 (1.O)C 

1 (1.0) 3 (1.0) 

5 5 

61 60 

12** (1.0) 37** (1.0) 

0 

5 

0 

5 

0 

5 

1 (1.0) 

5 

61 59 60 

3 (1.3) 2 (1.0) 1 (1.0) 17** (1.0) 

60 

a Number of animals with nose examined microscopically 

** Significantly different (P50.01) from the control group by the logistic regression test 

Average severity grade of lesion in affected animals: 1 = minimal; 2 = mild; 3 = moderate; 4 = marked 

Number of animals with lesion 

Liver: Statistically significant increases in the inci- 19/60; Table D3). However, these incidences did 

dence of hepatocellular adenoma or carcinoma not exceed the range of historical control data for the 

(combined) occurred at the end of 2 years in combined incidence of this neoplasm in 2-year NTP 

0.25 mg/m3 female mice (0 mg/m3, 18/61; inhalationstudies[148/759(19.5% * 12.4%); range, 

0.25 mg/m3, 28/59; 0.5 mg/m3, 15/60; 1 mg/m3, 3% to 54%]. 
Results 85 

and 1 mg/m3 lung burden study females were signifi- similar to that in the controls (Table 14). 

(Tables 30 and 13). Absolute lung weights of 0.5 female mice exposed to 0.25, 0.5 or 1 mg/m3 was 

exposed groups were below the limit of detection the concentration of nickel in the kidney of male and 

nickel burden parameters measured in control and 15 months. Also at the 15-month interim evaluation, 

At the 7- and 15-month interim evaluations, lung cantly greater than those of the controls at 

Tissue Burden Analyses 

Lung Weight and Lung Burden in Mice in the 2-Year Inhalation Study of Nickel Sulfate Hexahydratea 

TABLE 30. 

0 mg/m3 0.25 mg/m3 0.5 mg/m’ 1 mg/m3 

7-Month Interim Evaluation 

n 

Male 

pg Nilg control lung 

pg Ni/g lung 

pg Nillung 

Absolute lung wt (g) 

15-Month Interim Evaluation 

n 

pg NUg control lung 

pg Nilg lung 

pg Nillung 

Absolute lung wt (g) 

7-Month Interim Evaluation 

n 

Female 

pg Nilg control lung 

pg Ni/g lung 

pg Nillung 

Absolute lung wt (g) 

15-Month Interim Evaluation 

n 

pg Nilg control lung 

pg Nilg lung 

pg Nillung 

Absolute lung wt (g) 

0.230 f 0.013 

5 

- b 

- 

0.208 f 0.009 

4 

- 

- 

- 

- 

0.221 f 0.020 

4 

- 

- 

0.205 f 0.005 

5 

- 

- 

- 

- 

4 5 5 

0.239 f 0.023 0.294 f 0.024 0.251 f 0.028 - - - 

- - - 

- - - 

5 3 3 

0.223 f 0.028 0.204 f 0.017 0.251 f 0.006 

- - - 

- - - 

- - - 

5 5 5 

0.218 f 0.015 0.212 f 0.009 0.257 f 0.009 - - - 

- - - 

- - - 

5 5 5 

0.214 f 0.007 0.225 f 0.006* 0.275 f 0.004** 

- - - 

- - - - - - 

a Mean f standard error; statistical tests were performed on unrounded data. 

** PSO.01 

* Significantly different (PSO.05) from the control group by Williams’ or Dunnett’s test 

Results were below 0.323 pg Ni (7 months) or 0.256 pg Ni (15 months) (the limits of detection), or below the level of quantitation. 
86 Nickel Sulfate Hexahydrate, NTP TR 454 

GENETIC TOXICOLOGY 

Nickel sulfate hexahydrate (500 to 800 pg/mL) was McGregor et al., 1988). A positive response was 

tested for induction of trifluorothymidine resistance observed in the absence of S9. The test was not 

in L5178Y mouse lymphoma cells (Table El; performed with S9. 
septae. H&E, 215 x 

connective tissue and reactive alveolar epithelial hyperplasia thicken alveolar 

2 years. Macrophages and cellular debris are within alveolar spaces; H&E, 135x 

F344/N rat exposed to 0.5 mg/mJ nickel sulfate hexahydrate by inhalation for rat exposed to 0.5 mglm3 nickel sulfate hexahydrate by inhalation for 2 years. 

Chronic active inflammation subjacent to the pleura in the lung of a male Proteinaceous material within alveolar spaces in the lung of a male F344/N 

PLATE 1 PLATE 2 

contain proteinaceous material or macrophages. H&E, 270 x 

of neutrophils and cell debris within central alveolar spaces; other alveoli (arrow) of the layers of this pseudostratified epithelium. H&E, 135 X 

1 mglm’ nickel sulfate hexahydrate by inhalation for 2 years. Note aggregates exposed to 1 mg/m3 nickel sulfate hexahydrate for 2 years. Note thinning 

Chronic active inflammation in the lung of a male B6C3FI mouse exposed to Atrophy of the olfactory epithelium in the nose of a male B6C3F, mouse 

PLATE 3 PLATE 4 
87 

DISCUSSION AND CONCLUSIONS 

respiratory system. 

in rats and mice, the major toxicity was to the 

these inhalation studies of nickel sulfate hexahydrate 

organs other than the lung have been examined. In 

have been established or where toxic effects in 

sure concentration and toxic response relationships 

of nickel sulfate reported in which inhalation expotions (Doll et al., 1990). There have been no studies 

also occur during other mining and refinery operacompound used in electroplating, and exposure may 

Nickel sulfate hexahydrate is a water-soluble nickel 

ered due to pulmonary inflammation and necrosis. 

with exposure concentration. Deaths were considthelium. The severity of the lung lesions increased 

degeneration, and necrosis of the respiratory epiin the lungs of rats and mice included inflammation, 

findings that corresponded to the respiratory toxicity 

exposed groups of rats and mice. Histopathologic 

denced by labored respiration, occurred in all 

to 7 mg/m3 or greater. Respiratory toxicity, eviof the study, as did all male and female mice exposed 

female rats exposed to 60 mg/m3 died before the end 

the lethal effects of exposure; two male rats and all 

(Table 31). Mice were more susceptible than rats to 

60 mg/m3 (equivalent to 0.7 to 12.2 mg nickel/m3) 

nickel sulfate hexahydrate at concentrations of 3.5 to 

In the 16-day studies, rats and mice were exposed to 

dose-response effects in that species. 

the 16-day mouse study prevented an evaluation of 

50% of those in the 3.5 mg/m3 rats. Early deaths in 

in mice exposed to 3.5 mg/m3 were approximately 

increase with exposure concentration. Lung burdens 

nickel concentrations in the lungs of rats did not 

tions of nickel sulfate hexahydrate (Table 32). The 

special study groups exposed to selected concentrawere measured in the lungs of rats and mice from 

At the end of the 16-day studies, quantities of nickel 

in which the reported lung half-life is 1 to 3 days 

by toxicokinetic studies of nickel sulfate hexahydrate 

rapidly cleared from the rat lung, a finding supported 

These data indicate that nickel sulfate hexahydrate is 

presented by Oskarsson and Tjalve (1979). 

nickel-binding constituents in the lung has been 

to macromolecules within the lung. Evidence for 

small fraction of the delivered nickel may be bound 

increasing exposure concentrations implies that a 

amount of nickel within the lung over a range of 

not nickel lung burden. The relatively constant 

toxic effects are related to exposure concentration and 

(Medinsky et al., 1987). The data also indicate that 

lesions present in the kidney. 

were no treatment-related gross or histopathologic 

kidneys of rats at all exposure concentrations, there 

quantifiable amounts of nickel were found in the 

through the urine (Medinsky et al., 1987). Although 

the major route of elimination of soluble nickel is 

and these results are consistent with the finding that 

increased in proportion to exposure concentration, 

exposed rats. The quantity of nickel in the kidney 

cated by the presence of nickel in the kidney of 

The distribution of nickel to other tissues was indinickel oxide study. 

hydrate and nickel subsulfide studies, but not in the 

epithelium was observed in the nickel sulfate hexa16-day studies. Atrophy of the nasal olfactory 

concentrations in the nickel sulfate hexahydrate 

pounds, but these lesions occurred at lower exposure 

lesions were observed with all three nickel comfide or nickel oxide (Table 33). Lung inflammatory 

more toxic to rats and mice than either nickel subsulIn the 16-day studies, nickel sulfate hexahydrate was 

compounds (cadmium oxide; NTP, 1995), and is 

characteristic of inhalation exposure to other metal 

nodes. The nasal toxicity reported in these studies is 

tory changes in the lung, nose, and bronchial lymph 

evidenced by increases in lung weights and inflammamice caused treatment-related respiratory toxicity 

sulfate hexahydrate/m3 in rats and 0.5 to 2 mg/m3 in 

ever, exposure concentrations of 0.25 to 2 mg nickel 

weight changes in rats and mice (Table 34). Howrelated deaths and only minimal effects on body 

In the 13-week studies, there were no treatment- 
88 Nickel Sulfate Hexahydrate, NTP TR 454 

ogy in rats or mice. 

cant effects on sperm morphology or vaginal cytolexposure. Nickel sulfate hexahydrate had no signifiepithelium to the metal compound, not to systemic 

most likely due to direct exposure of the olfactory 

1984; Benson et al., 1994). 

compound from the lung (Valentine and Fisher, 

relatively rapid clearance of this soluble nickel 

retention of nickel subsulfide is low because of a 

nickel oxide in rats (Benson et al., 1994). The 

sulfate hexahydrate (Medinsky et al., 1987) and 

oxide. are consistent with previous studies of nickel 

and very high retention in those exposed to nickel 

lungs of rats exposed to nickel sulfate hexahydrate 

(Table 32). The very low retention of nickel in the 

ate, nickel subsulfide, and nickel oxide, respectively 

and 80 pg nickel/g lung for nickel sulfate hexahydrsure to approximately 0.4 mg nickel/m3 were 6, 7, 

the lungs of male rats following 13 weeks of expogreater than in male mice. Nickel concentrations in 

amount of nickel in the lungs of female mice was 

of male and female rats was similar, although the 

state (Table 32). The amount of nickel in the lungs 

present in the lungs of rats and mice reached a steady 

After 13 weeks of exposure, the amount of nickel 

female mice (Haley et al., 1990). 

and the lymphocytic proliferative assay in these 

natural killer cell assay, the mixed lymphocyte assay, 

In addition, negative results were obtained in the 

in female mice exposed to nickel sulfate hexahydrate. 

cell response following intraperitoneal immunization 

There were no alterations in the antibody-forming 

altered by exposure to nickel sulfate hexahydrate. 

killer cell activity. Systemic mmunity was not 

alveolar macrophage phagocytosis or spleen natural 

deposited antigen. There were no major changes in 

ability of the animals to respond to intratracheally 

associated lymph nodes, but this did not affect the 

was an increase in the number of cells in the lunghydrate exposure observed in the immunologic assays 

The most significant effect of nickel sulfate hexaand that there had been an influx of inflammatory 

that some pulmonary inflammation was in progress, 

Increased numbers of total nucleated cells indicated 

male and female rats and mice (Benson et al., 1989). 

lung lavage fluid were generally similar between 

At 13 weeks, biochemical changes monitored in the 

paralleled histopathologic findings. 

present. The changes noted in these assays generally 

numbers of polymorphonuclear leukocytes were also 

were macrophages; however, modestly increased 

cells into the pulmonary tissue. Most of these cells 

nickel salts (0.1 mg nickel/m3) (ACGIH, 1993). 

present threshold limit value levels of water-soluble 

hexahydrate in rats and mice occurs at or below the 

Respiratory toxicity produced by nickel sulfate 

mately 0.25 mg/m3 for rats and 1.0 mg/m3 for mice. 

The no-effect level for nasal toxicity was approxi- 

(equivalent to 0.11 mg nickel/m3) in mice (Table 34). 

lent to 0.06 mg nickel/m3) in rats and 0.5 mg/m3 

olfactory epithelial atrophy was 0.25 mg/m3 (equivalung alveolar hyperplasia and inflammation and 

In the present 13-week studies, the no-effect level for 

studies. 

active inflammation was observed in the 13-week 

were just below concentrations at which mild chronic 

exposure concentrations used in the 2-year studies 

possibility of reduced lung function. The highest 

ered to be potentially life threatening because of the 

Chronic active inflammation of the lung was considCosta et al., 1994). 

alveolar/bronchiolar epithelium (Lee et al., 1993; 

extensive damage to cytoplasmic components of the 

compounds are phagocytized and do not cause 

trast, it is thought that the water-insoluble nickel 

plasmic proteins, thereby causing toxicity. In conacross the cell membrane and interaction with cytohigher concentrations of free nickel ions for diffusion 

compounds because the availability of relatively 

are thought to be more toxic than the insoluble nickel 

being the most toxic. The soluble nickel compounds 

the most soluble nickel (nickel sulfate hexahydrate) 

nickel compounds in water and biological fluids, with 

nasal toxicity reflects the relative solubility of the 

nickel oxide the least toxic (Table 34). The lung and 

nickel sulfate hexahydrate was the most toxic and 

Results of the three 13-week studies demonstrate that 

female mice exposed to 0.5 mg/m3 and those of 

mean body weights of female rats, male mice, and 

were similar to those of the controls. However, 

(Table 35). Mean body weights of exposed male rats 

there were no treatment-related effects on survival 

In the 2-year studies of nickel sulfate hexahydrate, 
Discussion and Conclusions 89 

the last year of the study. 

slightly less than those of the controls during most of 

0.25 mg/m3 female rats and female mice were 

hydrate. 

after 12 days of exposure to nickel sulfate hexations of nickel caused lung toxicity in rats and mice 

0.88 mg nickel/m3 to mice, and similar concentrastudies delivered 0.73 mg nickel/m3 to rats and 

concentration used in the nickel subsulfide 2-year 

sulfate hexahydrate studies. The highest exposure 

were fatal to rats and mice in the 16-day nickel 

to mice, and these nickel exposure concentrations 

delivered 2 mg nickel/m3 to rats and 4 mg nickel/m3 

concentration used in the nickel oxide 2-year studies 

response curve. For example, the highest exposure 

because nickel sulfate hexahydrate has a steeper toxic 

of the other nickel compounds (Table 31), primarily 

2-year studies were lower than those used in studies 

concentrations used in the nickel sulfate hexahydrate 

oxide or nickel subsulfide (Table 35). The exposure 

the lungs of rats and mice exposed similarly to nickel 

hexahydrate were less severe than those observed in 

posed for 2 years by inhalation to nickel sulfate 

Toxic responses in the lungs of rats and mice exresponses were observed. 

these studies, no treatment-related carcinogenic 

Kasprzak et al., 1983; Pott et al., 1989, 1992). In 

local injection (Payne, 1964; Gilman, 1962, 1966; 

tial of nickel sulfate hexahydrate administered via 

studies which have examined the carcinogenic poten2 years (Table 35). This is consistent with previous 

or mice exposed to nickel sulfate hexahydrate for 

No exposure-related lung neoplasms occurred in rats 

genic events. 

the development/progression of endogenous mutagland neoplasms by decreasing cell proliferation and 

may affect the development of spontaneous mammary 

last year of the study. Decreases in body weights 

were decreased approximately 7 % to 10 % during the 

mately 2% to 6% and those of 0.5 mg/m3 female rats 

of 0.25 mg/m3 female rats were decreased approxiwith decreased body weights; the mean body weights 

in mammary gland neoplasms in rats are associated 

neoplasms. Rao et al. (1987) reported that decreases 

decreased incidences of spontaneous mammary gland 

sulfate hexahydrate during the 2-year study had 

Female rats exposed to 0.25 or 0.5 mg/m3 nickel 

exposed to nickel sulfate hexahydrate. 

lesions over exposure time were less in animals 

fide studies, but he severity and progression of 

similar to those in the nickel oxide and nickel subsulhad a spectrum of inflammatory changes in the lung 

rats and mice exposed to nickel sulfate hexahydrate 

significant alterations compared with controls. Both 

olfactory epithelium of exposed animals did have 

present studies, the lung, bronchial lymph node, and 

observed in male or female rats or mice in the 

Although no exposure-related neoplasms were 

1 mg/m3 mice. 

these lung lesions were observed primarily in 0.5 and 

hyperplasia, proteinosis, and cellular infiltration; 

related lung lesions were diagnosed as inflammation, 

of chronic active inflammation. In mice, treatmentlesions were considered to be the various components 

fibrosis, hyperplasia, and alveolar proteinosis; these 

in 0.25 and 0.5 mg/m3 rats and was characterized by 

nickel sulfate hexahydrate occurred for the most part 

Respiratory toxicity in the lung of rats exposed to 

particulates in rats. In the present inhalation studies 

but it has been observed in studies of other inhaled 

spontaneous alveolar/bronchiolar neoplasms in rats, 

squamous differentiation is not characteristic of 

exposed to nickel subsulfide. Such proliferative 

in 4 of 14 alveolarlbronchiolar carcinomas in rats 

present in 2 of 21 alveolar/bronchiolar adenomas and 

differentiation. Similar squamous differentiation was 

exposed to nickel subsulfide had marked squamous 

and two of the alveoladbronchiolar adenomas in rats 

oxide and four of the alveolar/bronchiolar carcinomas 

bronchiolar carcinomas in rats exposed to nickel 

exposed to the same compound. Five of the alveolar/ 

proliferative and fibrotic lung lesions than were rats 

three nickel studies, mice were less susceptible to 

typical of spontaneously occurring neoplasms. In all 

exposed to nickel oxide or nickel subsulfide were 

exposed to nickel sulfate hexahydrate and in mice 

Alveolar/bronchiolar neoplasms in rats and mice 

mice for all three compounds were also similar. 

compounds; lung lesions in the control groups of 

the lung of the rats in the control groups for all three 

appearance, and severity of spontaneous lesions in 

or nickel subsulfide. There was similar incidence, 

exposure to nickel sulfate hexahydrate, nickel oxide, 

lung pathology in rats and mice after 2 years of 

Some generalities can be made about the comparative 
90 Nickel Sulfate Hexahydrate, NTP TR 454 

to form squamous epithelium. 

nickel in any form may stimulate rodent lung tissue 

or squamous cysts in the lungs. This suggests that 

but some exposed animals had squamous metaplasia 

lung neoplasms in exposed groups of rats or mice, 

hexahydrate, there were no increased incidences of 

with soluble (rather than particulate) nickel sulfate 

subsulfide. 

fewer lung neoplasms than did rats exposed to nickel 

However, rats exposed to nickel oxide developed 

(approximately 300 to 1,100 pg nickel/g lung). 

of nickel deposited in the lung were much greater 

did not. In nickel oxide rats at 15 months, amounts 

response in the rat lung, nickel sulfate hexahydrate 

nickel subsulfide caused a clear carcinogenic 

hexahydrate and nickel subsulfide studies, and while 

mice in all exposure groups in the nickel sulfate 

than 30 pg nickel/g of lung was measured in rats and 

(Table 32). At the 15-month interim evaluation, less 

time points during the course of exposures 

sured by atomic absorption spectroscopy at various 

the amount of nickel deposited in the lung as meanickel compound studies are not a direct function of 

Incidences of lung neoplasms observed in the three 

sulfate hexahydrate. 

are water-soluble nickel compounds such as nickel 

delivered at higher concentrations to the nucleus than 

causing more critical cancer damage because they are 

water-insoluble nickel compounds are capable of 

was not. Costa et al. (1994) has uggested that 

soluble nickel compound (nickel sulfate hexahydrate) 

carcinogenic to the rat lung, whereas the watercompounds (nickel oxide and nickel subsulfide) were 

nickel compounds showed that water-insoluble nickel 

The results of the present studies with the three 

nickel subsulfide had significant parenchymal damage 

rats. Additionally, rats exposed to nickel oxide or 

ties of exposed and control nickel sulfate hexahydrate 

greater than the differences observed between severinickel oxide and nickel subsulfide studies were 

lesions observed in exposed and control rats in the 

differences between severities of lung inflammatory 

with significant positive trends. However, the 

in rats exposed to nickel sulfate hexahydrate occurred 

Thc incidences of inflammatory lung lesions observed 

sulfate hexahydrate-exposed animals. 

was not observed in the nickel subsulfide- or nickel 

nodes of rats and mice exposed to nickel oxide, but 

Pigment occurred in the lungs and bronchial lymph 

were noteworthy in the nickel oxide-exposed rats. 

condensed appearance of the intra-alveolar protein 

exposed rats. Exposure-related pigment and the 

were somewhat more prominent in nickel subsulfideproliferation, and foci of collapse or consolidation 

cellular debris, regenerative alveolar epithelial 

and nickel oxide-exposed rats. Foci of necrotic 

were multifocally extensive in both nickel subsulfideproliferation apparently secondary to inflammation 

spaces. Fibrosis, consolidation, and cellular 

foamy macrophages were widespread in alveolar 

protein accumulations with variable numbers of 

1 mg/m3 nickel subsulfide or 2.5 mg/m3 nickel oxide, 

secondary to inflammation. In rats exposed to 

cells with little evidence of necrotic cell debris. 

nickel subsulfide were predominantly mononuclear 

inflammatory foci in mice exposed to nickel oxide or 

mice exposed to nickel sulfate hexahydrate, while 

and necrotic cell debris were relatively common in 

and neutrophils. Inflammatory foci with neutrophils 

various combinations of lymphocytes, macrophages, 

vessels; and multifocal intra-alveolar aggregates of 

macrophages; mononuclear inflammatory cells around 

reactions, including: intra-alveolar protein and 

studies and were composed of various inflammatory 

lungs of exposed mice were similar in all three nickel 

oxide-exposed mice, nonneoplastic lesions in the 

With the exception of the pigment observed in nickel 

in the Kristiansand refinery workers (Norway) or the 

subpopulations such as in the electrolysis departments 

sulfate hexahydrate alone. However, in certain 

studies to obtain a risk from exposure to nickel 

Therefore, it was not possible from the human 

different nickel exposures throughout their careers. 

workers tended to work in several departments with 

subsulfide exposures occurred simultaneously, and 

nickel sulfate hexahydrate, nickel oxide, and nickel 

operations throughout the world. In most cases, 

nickel compounds at various refineries or nickel 

Doll et al. (1990) estimated exposures to individual 

In areas where epidemiology studies were available, 
Discussion and Conclusions 91 

subsulfide, or nickel oxide. 

or mice exposed to nickel sulfate hexahydrate, nickel 

neoplasms were observed in the nasal cavities of rats 

neoplasms (Doll et al., 1990). No exposure-related 

other forms of nickel in causing lung and nasal 

thought to have a synergistic role with oxidic or 

sulfidic, and/or metallic nickel. Soluble nickel was 

risk of lung cancer in workers also exposed tooxidic, 

evidence that exposure to soluble nickel increased the 

particularly high (1 to 5 mg/m3), and there was 

(Canada), nickel sulfate hexahydrate exposures were 

hydrometallury departments at the Clydach refinery 

exposure to other agents. 

development of cancer when there is concomitant 

soluble nickel salts may be a factor in the eventual 

1994). These studies suggest that exposure to waterultraviolet-induced photoproducts (Hartwig et al., 

excision repair in mammalian cells and repair of 

of DNA-damaging agents by inhibiting nucleotide 

shown to enhance the cytotoxicity and mutagenicity 

soluble nickel salts (i.e. nickel chloride) have been 

environmental agents. In in vitro studies, waterthe carcinogenic response from exposures to other 

suggest that water-soluble nickel salts may enhance 

Experimental studies have provided evidence to 

CONCLUSIONS 

or 0.22 mg nickel/m3). 

mice exposed to 0.25, 0.5, or 1 mg/m3 (0.06, 0.11, 

nickel sulfate hexahydrate in male or female B6C3F, 

There was no evidence of carcinogenic activily of 

0.5 mg/m3 (0.03, 0.06, or 0.11 mg nickel/m3). 

female F344/N rats exposed to 0.12, 0.25, or 

activity* of nickel sulfate hexahydrate in male or 

studies, there was no evidence of carcinogenic 

Under the conditions of these 2-year inhalation 

epithelium. 

bronchial lymph node; and atrophy of the olfactory 

lung; lymphoid and macrophage hyperplasia of the 

interstitial infiltration, and alveolar proteinosis of the 

epithelial hyperplasia), macrophage hyperplasia, 

active inflammation, bronchialization (alveolar 

2 years resulted in increased incidences of chronic 

mice to nickel sulfate hexahydrate by inhalation for 

and atrophy of the olfactory epithelium. Exposure of 

lymphoid hyperplasia of the bronchial lymph node; 

plasia, alveolar proteinosis, and fibrosis of the lung; 

of chronic active inflammation, macrophage hyperinhalation for 2 years resulted in increased incidences 

Exposure of rats to nickel sulfate hexahydrate by 

* Explanation of Levels of Evidence of Carcinogenic Activity is on page 10. A summary of the Technical Reports Review Subcommittee 

comments and the public discussion on this Technical Report appears on page 12. 
92 Nickel Sulfate Hexahydrate, NTP TR 454 

of Nickel Sulfate Hexahydrate, Nickel Subsulfide, and Nickel Oxidea 

Comparison of Exposure Concentrations in the 16-Day, 13-Week, and 2-Year Studies 

TABLE 31 

Amount of Compound Amount of Nickel 

16-Day Studies 

Nickel Sulfate 

Nickel Subsulfide (73.3% Ni) 

Hexahydrate (22.3% Ni) 

0, 0.6, 1.2, 2.5, 5, 10 

0, 3.5, 7, 15, 30, 60 

Nickel Oxide (78.6% Ni) 0, 1.2, 2.5, 5, 10, 30 

13-Week Studies 

Nickel Sulfate 

Hexahydrate (22.3% Ni) 0, 0.12, 0.25, 0.5, 1, 2 

Nickel Subsulfide (73.3% Ni) 0, 0.15, 0.3, 0.6, 1.2, 2.5 

Nickel Oxide (78.6% Ni) 0, 0.6, 1.2, 2.5, 5, 10 

Nickel Sulfate 

2-Year Studies 

Hexahydrate (22.3% Ni) 

Mice 

Rats 

0, 0.25, 0.5, 1 

0, 0.12. 0.25, 0.5 

Nickel Subsulfide (73.3% Ni) 

Mice 

Rats 

0, 0.6, 1.2 

0, 0.15, 1 

Nickel Oxide (78.6% Ni) 

Mice 

Rats 

0, 1.25, 2.5, 5 

0, 0.62. 1.25, 2.5 

0, 0.9, 2.0, 3.9, 7.9, 23.6 

0, 0.44. 0.88, 1.83, 3.65, 7.33 

0, 0.7, 1.4, 3.1, 6.1, 12.2 

0, 0.4, 0.9, 2.0, 3.9, 7.9 

0, 0.11, 0.22. 0.44, 0.88, 1.83 

0, 0.03, 0.06, 0.11, 0.22, 0.44 

0, 0.06, 0.11, 0.22 

0, 0.03. 0.06, 0.1 1 

0, 0.44, 0.88 

0, 0.11. 0.73 

0, 1.0, 2.0, 3.9 

0, 0.5, 1.0, 2.0 

a Amounts of nickel and nickel compounds are expressed in mg/m3. Occupational exposure limits in the United States: 1 mg Ni/m3 for 

nickel metals, 0.1 mg Ni/m3 for soluble nickel compounds. 
Lung Burden Analyses in the lCDay, 13-Week, and 2-Year Studies of Nickel Sulfate Hexahydrate, Nickel Subsulfide, and Nickel Oxidea 

TABLE 32 

g. E 

E! 

0 0.12 0.5 2 3.5 1530 0 0.15 0.6 2.5 10 

Nickel Sulfate Hexahvdrate (22.3% Ni) Nickel Subsulfide (73.3% Ni) 

(0.4) (0.9) e(2.0) (3.9) (7.9) 

0 0.6 1.2 2.5 5 10 

Nickel Oxide (78.6% Ni) 0 

ul 

(mg Ni/m’) 

Dose mg/m’ 

(0.03) (0.06) (0.44)(0.7) (3.1) (6.1) (0.11) (0.44) (1.83) (7.33) 3 

a 

3 

P) 

n 

Female Mice 

Male Mice 

Female Rats 

Male Rats 

16-Day Studies 

(continued) 

Female Mice 

Male Mice 

Female Rats 

Male Rats 

13-Week Studies 

-4 

-1 

27 

16 

3 - 10 20 13 - 32 46 84 

4 - 8 20 8 - 31 43 71 

-5 7 18 

-5 7 17 

-3 11 17 

-6 13 23 

- 80 181 524 

- 42 202 736 
Lung Burden Analyses in the 16-Day, 13-Week, and 2-Year Studies of Nickel Sulfate Hexahydrate, Nickel Subsulfide, and Nickel Oxide (continued) 

TABLE 32 

(mg Ni/m3) 

Dose mg/m3 

(0.03) (0.06) (0.11) (0.22) (0.44) 

0 0.12 0.25 0.5 1 2 0 0.15 0.6 1 1.2 

Nickel Sulfate Hexahydrate (22.3% Ni) 

(0.11) (0.44) (0.73) (0.88) 

Nickel Subsulfide (73.3% Ni) 

0 0.62 1.25 2.55 10 

Nickel Oxide (78.6% Ni) 

(0.5) (1.0) (2.0) (3.9) (7.9) 

~~~ ~ 

7-Month Interim Evaluation 

Male Rats 

Female Mice 

Male Mice 

Female Rats 

Female Mice 

Male Mice 

Female Rats 

Male Rats 

15-Month Interim Evaluation 

-6 

9 

9 

-6 

- 

10 

10 11 

- 14 

-4 3 

-4 7 

- 12 

26 

20 

- 15 

- 175 388 701 

- 173 477 713 

- 

169 533 861 

162 441.034 

- 

- 328 746 1,116 

- 262 706 949 

- 

451 1,237 2,258 

331 959 1,798 

- 

a Values represent mean amounts of nickel (fig Ni/g lung). Lung burden groups included five to seven animals. 

Results were below the limit of detection. 

P 

cn 

P 
Selected Results in the 16-Day Inhalation Studies of Nickel Sulfate Hexahydrate, Nickel Subsulfide, and Nickel Oxidea 

TABLE 33 

(mg Nilm’) 

Dose mg/m’ 

(0.7) (1.4) (3.1) (6.1) (2.2) 

0 3.5 7 15 30 60 0 0.6 1.2 2.5 5 10 0 1.2 2.5 5 10 30 

Nickel Sulfate Hexahydrate Nickel Subsulfide Nickel Oxide R 

g. P 

(0.44) (0.88) (1.83) (3.65) (7.33) (0.9) (2.0) (3.9) (7.9) (23.6) J 

a2 

Male Rats 

Survival 

Absolute Lung Weightsb 

(Relative to Controls) 

Final Mean Body Weights 

Female Rats 

Survival 

(Relative to Controls) 

Final Mean Body Weights 

Absolute Lung Weights 

m 

E 

6 

55 5553 555554 55555 5 

5 

5- 

P 

- 12% 60% 56% 55% 45% - 109% 105% 92% 72% 52% - 99% 101% 99% 99% 96% 

0.98 1.44** 1.45**1.40* 1.40* 1.62** 1.13 1.41 1.60* 1.59* 1.82**1.54** 1.06 1.00 1.06 0.96 1.20* 1.36** 

55 5540 555555 55555 5 

- 82% 71% 68% 63% - - 99% 97% 91% 78% 51% - 103% 103% 104% 101% 99% 

0.76 1.28* 1.28* 1.32* 1.40**1.52** 0.82 1.12**1.12**1.36**1.42**1.25** 0.78 0.86 0.90 0.82 1.04** 1.12** 

(continued) 
Selected Results in the 16-Day Inhalation Studies of Nickel Sulfate Hexahydrate, Nickel Subsulfide, and Nickel Oxide (continued) 

TABLE 33 

(mg Nilm') 

Dose mg/m' 0 0.6 1.2 2.5 5 10 0 1.2 2.5 5 10 30 

Nickel Oxide 

0 3.5 7 15 30 60 

Nickel Sulfate Hexahydrate Nickel Subsulfide 

(0.7) (1.4) (3.1) (6.1) (2.2) (0.44) (0.88) (1.83) (3.65) (7.33) (0.9) (2.0) (3.9) (7.9) (23.6) 

Male Mice 

Survival 55 0000 454550 55545 5 

(Relative to Controls) 

Final Mean Body Weights - 95% - - - - - 99% 90% 92% 86% - - 100% 100% 98% 102% 94% 

Absolute Lung Weights 0.20 0.24 0.40**0.36**0.36**0.38** 0.22 0.20 0.22 0.28 0.31**0.38** 0.20 0.16 0.20 0.13** 0.20 0.20 

Female Mice 

Survival 55 0000 455550 55555 5 

(Relative to Controls) 

Final Mean Body Weights - 96% - - - - - 106% 104% 101% 99% - - 100% 96% 100% 95% 95% 

Absolute Lung Weights 0.16 220.36**0.36**0.38**0.40** 0.20 0.21 270.36* 0.25 0.16 0.16 0.14 0.18 0.12 0.20 

a Survival data indicate number of animals surviving. Five animals initially in group. Final mean body weight? are not presented for groups with 100% mortality. 

** PSO.01 

* Significantly different (P10.05) from the control by Williams' or Dunnett's test 

Organ weights are given in grams. 
Selected Results in the 13-Week Inhalation Studies of Nickel Sulfate Hexahydrate, Nickel Subsulfide, and Nickel Oxidea 

TABLE 34 

~- ~ ~~ 

G;’ 

(0.03) (0.06) (0.11) (0.22) (0.44) 

Nickel Sulfate Hexahvdrate 

0 0.12 0.25 0.5 1 2 0 0.15 0.3 0.6 1.2 2.5 0 0.6 1.2 2.5 5 10 

Nickel Subsulfide Nickel Oxide n 

E 

(mg Ni/m3) 

Dose mg/m3 g. 

(0.11) (0.22) (0.44) (0.88) (1.83) (0.4) (0.9) 12.0) (3.9) (7.9) J 

a 

Male Rats 6 

J 

Survival 10 10 10 10 10 9 10 10 10 10 10 10 10 10 10 9 10 10 s 

E. 

0- 

(Relative to Controls) 

Final Mean Body Weights R - 99% 103% 96% 102% 95% - 100% 95% 96% 99% 93% - 103% 104% 99% 102% 100% 

Absolute Lung Weights 1.35 1.25 1.51* 1.64**2.14**2.22** 1.33 1.74**1.83**2.30**2.63**2.42** 1.18 1.35**1.47**1.70**1.91** 2.47** 

Alveolar Macrophage, 

Nonneoplastic Lung Lesions 

Hyperplasia 

(Severity) 

(Severity) 

(Severity) 

(Severity) 

(Severity)b 

Pigment 

Interstitial Infiltrate 

Inflammation, Granulomatous 

Inflammation, Chronic Active 

0 10 10 10 10 9 

00 02108 

00 0000 

(1.0) (1.5) (1.3) 

(1.0) (1.0) (1.0) (2.4) (3.6) 

10 15109 

(1 .O) (1.0) (1.0) (1.0) (1.1) 

00 0000 

000000 

0 2 9 10 10 10 

0 10 10 10 10 10 

(1.0) (1.3) (1.8) (2.9) (3.7) 

(1.1) (1.5) (1.6) (3.4) (3.8) 

000000 

0011098 

(1.0) (1.9) (2.1) (1.2) 

0679910 

0 0 1210 10 

00003 2 

0 0 0 210 10 

0 10 10 9 10 10 

(1.0) (1.0) (1.0) (1.0) (1.8) 

(1.0) (1.0) (1.4) (2.1) 

(2.0) 3

(1.0) (1.7) (3.0) 

(1.0) (1.0) (1.0) (1.5) (2.5) 

Nonneoplastic Nasal Lesions 

Atrophy, Olfactory Epithelium 00 01109 0 0 15 1010 00000 0 

(continued) 
Selected Results in the 13-Week Inhalation Studies of Nickel Sulfate Hexahydrate, Nickel Subsulfide, and Nickel Oxide (continued) 

TABLE 34 

(mg Nilm’) 

Dose mglm’ 

Nickel Sulfate Hexahvdrate 

0 0.12 0.25 0.5 1 2 0 0.15 0.3 0.6 1.2 2.5 

Nickel Subsulfide Nickel Oxide 

0 0.6 1.2 2.5 5 rn 

(0.03) (0.06) (0.11) (0.22) (0.44) (0.11) (0.22) (0.44) (0.88) (1.83) 

-- 

(0.4) (0.9) (2.0) (3.9) (7.9) 

Female Rats 

Survival 10 10 10 10 10 10 10 10 10 10 

10 10 10 10 

Final Mean Body Weights 

(Relative to Controls) - 96% 98% 98% 101% 95% - 101% 104% 101% 100% 99% - 101% 101% 98% 98% 100% 

Absolute Lung Weights 1.02 1.02 1.16**1.34**1.72**1.72** 1.01 1.29**1.39**1.82**1.85**1.81** 0.98 1.03 1.13* 1.55**1.61** 2.11** 

Alve6lar Macrophage, 

Nonneoplastic Lung Lesions 

Hyperplasia 

(Severity) 

(Severity) 

(Severity) 

(Severity) 

(Severity) 

Pigment 

Interstitial Infiltrate 

Inflammation, Granulomatous 

Inflammation, Chronic Active 

0 8 10 10 10 10 

0 0 0 41010 

00 0000 

(1.0) (1.3) (1.0) 

(1.0) (1.0) (1.1) (2.2) (3.6) 

0 0 0 61010 

00 0000 

(1.0) (1.0) (1.0) 

000000 

0 3 9 10 10 10 

0 10 10 10 10 10 

(1.0) (1.0) (1.9) (2.6) (3.8) 

(1.0) (1.7) (1.8) (2.9) (3.8) 

000000 

0029105 

(1.0) (1.7) (2.4) (1.6) 

0048810 

0 0 0 210 10 

00004 4 

00017 7 

0 10 8 10 10 10 

(1.0) (1.3) (2.7) 

(1.0) (1.0) (1.0) (1.4) (2.2) 

(1.0) (1.2) (1.8) 

(2.1) 0

(1.0) (1.0) (1.0) (1.2) 

Nonneoplastic Nasal Lesions 

Atrophy, Olfactory Epithelium 00 1 2 10 10 0008910 00000 0 

(continued) 
P 

9 

0 

c 

.- 

v1 

8 

x 

3 

0 00000 

~62.0 PZ'O 1ZO 1ZO ZZ'O IZ'O 

%L6 %86 XL6 %66 I101 - 

6 01 01 01 01 01 

01s5000 

**8Z'O*EZ'O IZ'O ZZ'O 02'0 61'0 

%L6 %IO1 %EO1 %901 I201 - 

01 6 8 01 01 8 

01000 

8200 

0000 

(0.1) (O't) 

**IE'O**5Z'O 1z.o OZ'O 

%201 %POI %POI goo1 

01 01 01 01 
Selected Results in the 13-Week Inhalation Studies of Nickel Sulfate Hexahydrate, Nickel Subsulfide, and Nickel Oxide (continued) 

TABLE 34 

(mg Ni/m3) 

Dose mg/m3 

(0.03) (0.06) (0.11) (0.22) (0.44) 

Nickel Sulfate Hexahydrate 

0 0.12 0.25 0.5 1 2 0 0.15 0.3 0.6 1.2 2.5 0 0.6 1.2 2.5 5 10 

Nickel Subsulfide Nickel Oxide 

(0.11) (0.22) (0.44) (0.88) (1.83) (0.4) (0.9) (2.0) (3.9) (7.9) 

Female Mice 

SUNiVal 7 10 10 10 10 10 

Final Mean Body Weights 

(Relative to Controls) - 105% 104% 105% 103% 97% 

Absolute Lung Weights 0.20 0.20 0.20 0.20 0.22 0.21** 

Nonneoplastic Lung Lesions 

Pigment 

Interstitial Infiltrate 

Inflammation, Granulomatous 

Inflammation, Chronic Active 

Fibrosis, Focal 

Alveolar Macrophage, Hyperplasia 

(Severity) 

(Severity) 

(Severity) 

(Severity) 

(Severity) 

(severity) 

00 010 

00 00 

(1 .O) 

00 00 

00 00 

0 

8 

(1.3) 

Nonneoplastic Nasal Lesions 

Atrophy, Olfactory Epithelium 00 0005 

10 8 10 9 10 8 

- 101% 100% 101% 101% 99% 

0.19 0.18 0.20 0.21 0.26**0.29** 

000000 

0000107 

000019 

0 0 4 9 1010 

(1.5) (2.0) 

(2.0) (1.6) 

(1.0) (1.0) (2.4) (2.6) 

000000 

023498 

(1.0) (1.0) (1.0) (1.4) (1.7) 

0001610 

9 10 7 10 10 9 

- 97% 100% 96% 94% 97% 

0.20 0.20 0.19 0.21 0.22 0.27** 

0 10 7 10 10 9 

00000 0 

(1.0) (1.0) (1.0) (1.1) (1.0) 

00001 3 

00000 1 

01046 8 

0 10 7 10 10 9 

(1.0) (1.0) (1.0) (1.0) (1.0) 

(1 .O) (1.0) (1.1) (1.1) 

(1 .O) 

(1.0) 1

00000 0 

a Survival data indicate number of animals surviving. Ten animals initially in group. Final mean body weights are not presented for groups with 100% mortality. 

** PSO.01 

* Significantly different (PIO.05) from the control by Williams' or Dunnett's test 

Nine animals initially in group. 

Average severity grade of lesions in affected animals: 1 =minimal, 2=mild, 3 =moderate, 4=marked 
Selected Results in the 2-Year Inhalation Studies of Nickel Sulfate Hexahydrate, Nickel Subsulfide, and Nickel Oxidea 

TABLE 35 

(mg Ni/m3) 

Dose mg/m' 

(0.11) (0.73) 

0 0.12 0.2s 0.5 0 0.1s 1 

Nickel Sulfate Hexahydrate (22.3% Ni) Nickel Subsulfide (73.3% Ni) Nickel Oxide (78.6% Ni) a 

(0.5) (1.0) (2.0) 

0 0.62 1.252.5 

E 

(0.03) (0.06) (0.11) 

g. 

P 

I 

Male Rats 

Survival 16/54 16/55 8

(Relative to Controls) 

Final Mean Body Weights - 99% 101% 

Absolute Lung Weights 

7-Month Interim Evaluation 1.67 1.62 1.65 

15-Month Interim Evaluation 2.12 2.48 2.50 

Alveolar/bronchiolar Proliferative Lesions and Neoplasms 

Alveolar Epithelial 

Adenoma or Carcinoma (Combined) 2b 0 1 

Carcinoma 1 

Adenoma 0 0 0 

Hyperplasia, Focal or Atypical 3 2 3 

2b 0 

Adrenal Medulla Proliferative Lesions and Neoplasms 

Hyperplasia 28 20 18 

Benign Pheochromocytoma 16 16 12 

Malignant Pheochromocytoma 0 3 2 

Benign or Malignant Pheochromocytoma 16 19 13 

Carcinogenic Activity No evidence 

(continued) 

21/55 

98 % 

3.00** 

1.89 

12 

1 

11 

26 

13/53 21/53 18/53 

- 98 % 85 % 

1.87 2.38** 3.48** 

2.27 3.31** 6.84** 

2 6 11** 

0 3 6* 

0 3 7* 

0 6* 11** 

26 22 10 

13 30** 37** 

0 2 11** 

14 30** 42** 

Clear evidence 

14/54 15/53 15/53 12/52 

- 100% 95% 93% 

1.72 1.85 2.43** 2.59** 

2.20 2.15 3.30** 4.09** 

0 2 5* 3 

0 1 3 2 

3 2 

6' 4' 

lb 0 

lb 1 

25 27 26 24 

21 24 26 32 

0 0 1 6* 

27 24 27 35** 

Some evidence 

s 

R 

E 

i;' 

2 

P 
Selected Results in the 2-Year Inhalation Studies of Nickel Sulfate Hexahydrate, Nickel Subsulfide, and Nickel Oxide (continued) 

TABLE 35 

5: 

(mg Ni/m3) 

Dose mglm’ 0 0.12 0.25 0.5 

Nickel Sulfate Hexahydrate (22.3% Ni) 

(0.11) (0.73) 

0 0.15 1 

Nickel Subsulfide (73.3% Ni) Nickel Oxide (78.6% Ni) h) 

0 0.62 1.25 2.5 

(0.03) (0.06) (0.11) (0.5) (1.0) (2.0) 

Female Rats 

Survival 22/52 17/53 28/53 29/54 25/53 25/53 28/52 21/53 26/53 20/53 26/54 

(Relative to Controls) 

Final Mean Body Weights - 97% 97% 94% - 96 % 78 % - 96% 92% 90% 

Absolute Lung Weights 

15-Month Interim Evaluation 

7-Month Interim Evaluation 1.25 1.22 1.22 1.45* 

1.37 1.57 1.49 1.82** 

1.31 1.75** 2.59** 

1.52 2.52** 4.14** 

1.14 1.31* 1.65** 1.78** 

1.56 1.79 2.41** 3.02** 

Alveoladbronchiolar Proliferative Lesions and Neoplasms 

Adenoma or Carcinoma (Combined) 0 0 0 1 

Carcinoma 0 0 0 0 

Adenoma 0 0 0 1 

Hyperplasia, Focal or Atypical 5 3 7 9 

Alveolar Epithelial 

Adrenal Medulla Proliferative Lesions and Neoplasms 

Hyperplasia 6 4 8 8 

Benign Pheochromocytoma 2 4 2 3 

Malignant Pheochromocytoma 0 0 0 0 

Benign or Malignant Pheochromocytoma 2 4 2 3 

Carcinogenic Activity No evidence 

2 6b.d 9* 

0 4 

2 5 5 

2 IO* 11** 2 1 6 6 

1 0 1 4 

0 0 5* 1 

1 0 Sd gd 

lb 

5 11 16** 

2 7 36** 

1 0 1 

3 7 36** 

8 12 14 22** 

4 7 6 18** 

0 0 0 0 

4 7 6 18** 

3 

Clear evidence Some evidence n 

e 

?? 

(continued) 

rn 

E 

P 

P 

01 
Selected Results in the 2-Year Inhalation Studies of Nickel Sulfate Hexahydrate, Nickel Subsulfide, and Nickel Oxide (coptinued) 

TABLE 35 

P 

m 

Dose mdm’ 

Nickel Sulfate Hexahydrate (22.3% Ni) 

0 0.6 1.2 

Nickel Subsulfide (73.3% Ni) 

0 1.25 2.5 5 

Nickel Oxide (78.6% Ni) 

0 0.25 0.5 1 

ra 

vl e 

p. I 

(mg Ni/m3) (0.06) (0.11) (0.22) (0.44) (0.88) (1.0) (2.0) (3.9) 0 

@ 

6 

a 

Male Mice 

Survival 26/61 324/62 5126/61 25/59 26/58 19/57 23/67 29/66 23/69 

Final Mean Body Weights 

(Relative to Controls) - 94% 97% 91% - 92 % 92 % - 93% 93% 93% 

Absolute Lung Weights 

7-Month Interim Evaluation 0.21 0.20 0.22 0.23 

15-Month Interim Evaluation 0.24 0.25 0.26 0.31** 

0.24 0.27 0.34** 

0.23 0.40** 0.41** 

0.19 0.21 0.24** 0.24** 

0.23 0.25 0.31* 0.38** 

Alveolarlbronchiolar Proliferative Lesions and Neoplasms 

Alveolar Epithelial 

Adenoma or Carcinoma (Combined) 13 18 7 8 

Carcinoma 9 13 4 3 

Adenoma 5 5 3 

Hyperplasia, Focal 0 0 0 0 0 0 0 

6 3 2 

7 2 4 

13 5 6 

1 1 2 0 

7 5 6 11 

4 10 9 6 

9 14 15 14 

Carcinogenic Activity No evidence No evidence No evidence 

(continued) 
Selected Results in the 2-Year Inhalation Studies of Nickel Sulfate Hexahydrate, Nickel Subsulfide, and Nickel Oxide (continued) 

TABLE 35 

c 

4 

(mg Nilm') 

Dose mglm' 0 0.6 1.2 

Nickel Sulfate Hexahydrate (22.3% Ni) Nickel Subsulfide (73.3% Ni) 

0 1.25 2.5 5 

Nickel Oxide (78.6% Ni) 

0 0.25 0.5 1 

(0.06) (0.11) (0.22) (0.44) (0.88) (1.0) (2.0) (3.9) 

Female Mice 

Survival 34/61 39/60 45/60 

(Relative to Controls) 

Final Mean Body Weights - 91% 94% 

Absolute Lung Weights 

7-Month Interim Evaluation 0.22 0.21 0.22 

15-Month Interim Evaluation 0.24 0.24 0.28 

Alveolarlbronchiolar Proliferative Lesions and Neoplasms 

Alveolar Epithelial 

Adenoma or Carcinoma (Combined) 7 6 10 

Carcinoma 4 3 9 

Adenoma 3 3 2 

Hyperplasia, Focal 0 1 1 

Carcinogenic Activity No evidence 

37/60 

88 % 

0.33** 

0.25 

36/58 34/59 38/60 

- 90% 86 % 

0.19 0.26* 0.29** 

0.26 0.39** 0.50** 

0 0 0 

3 1 1 

7 1 2 

9 2 3 

No evidence 

41/64 40166 42/63 38/64 

- 96% 94% 90% 

0.18 0.21 0.23 0.23 

0.25 0.26 0.29 0.34** 

0 0 1 0 

2 4 10* 3 

4 11 4 5 

6 15* 12 8 

Equivocal evidence 

a Survival data indicate number of animals survivinglnumber initially in group. 

** P10.01 

* Significantly different (P10.05) from the control by Williams' or Dunnett's test (lung weights) or the logistic regression test (incidences). 

Significantly different (P<O.O5) from the Lovelace Inhalation Toxicology Research Institute historical controls [4/208 (1.9%)] 

Significantly different (P<O.O5) from the Lovelace Inhalation Toxicology Research Institute historical controls [3/210 (1.4%)] 

Includes data for squamous cell carcinoma 

P 

01 

P 
105 

REFERENCES 

20, 33-42. 

infection following nickel inhalation. Environ. Res. 

( 1979). Enhancement of experimental respiratory 

Adkins, B., Jr., Richards, J.H., and Gardner, D.E. 

Substances and Disease Registry. 

Services, Public Health Service, Agency for Toxic 

(TP-92/14). U.S. Department of Health and Human 

(ATSDR) (1992). Toxicological profile for nickel 

Agency for Toxic Substances and Disease Registry 

Academic Press, London. 

and F.W. Sunderman, Jr., Ms.), pp. 55-58. 

nickel subsulfide. In Nickel Toxicology (S. S. Brown 

neoplasms in Fischer rats by intraocular injection of 

Sunderman, F. W., Jr. (1980). Induction of ocular 

Dohlman, H.G., Reid, M.C., and 

Albert, D.M., Gonder, J.R., Papale, J., Craft, J.L., 

in L5178YITK”- cells. Mutat. Res. 78, 279-288. 

of trifluorothymidine-resistant mutants by metal ions 

Amacher, D.E., and Paillet, S.C. (1980). Induction 

Technol. 13, 181-187. 

assessment of nickel in rats and dogs. J. Food Sci. 

Hennigar, G.R., , Jr. (1976). Long term toxicologic 

Ambrose, A.M., Larson, P.S., Borzelleca, J.F., and 

OH. 

Agents and Biological Exposure Indices, Cincinnati, 

Limit Values for Chemical Substances and Physical 

Hygienists (ACGIH) (1993). 1993-1994 Threshold 

American Conference of Governmental Industrial 

Environ. Health 61, 289-295. 

nine autopsied nickel workers. Znt. Arch. Occup. 

Determination of nickel in lung specimens of thirtyAndersen, I., and Svenes, K.B. (1989). 

36, 379-388. 

Mutagenicity of metal ions in bacteria. Environ. Res. 

Tandon, R.K., Crisp, P.T., and Ellis, J. (1985). 

Arlauskas, A., Baker, R.S.U., Bonin, A.M., 

New York. 

Research, pp. 362-365. John Wiley and Sons, 

Armitage, P. (1971). Statistical Methods in Medical 

subsulphide cr-Ni,Sz. Mutagenesis 5, 583-589. 

Marzin, D. (1990). Genotoxic activity of nickel 

Arrouijal, F.Z., Hildebrand, H.F., Vophi, H., and 

unsensitized donors. Mutagenesis 7, 183-1 87. 

lymphocytes from nickel-hypersensitized and nickelin genotoxic activity of cr-Ni,Sz on human 

Pestel, J., and Haguenoer, J.M. (1992). Differences 

Arrouijal, F.Z., Marzin, D., Hildebrand, H.F., 

tested by the U.S. NTP. Mutat. Res. 257, 229-306. 

carcinogenicity, and mutagenicity for 301 chemicals 

relationships among chemical structure, 

Ashby, J., and Tennant, R.W. (1991). Definitive 

mixture. J. Toxicol. Environ. Health 16, 547-552. 

tobacco grown on alow-cadmium soil-sludge 

mainstream particulates of cigarettes containing 

and Adams, J.D. (1985). Cadmium and nickel in 

Bache, C.A., Lisk, D. J., Doss, G.J., Hoffmann, D., 

University Press, Oxford. 

Scientific Publications No. 53, pp. 487-496. Oxford 

C. Rosenfeld, R. Saracci, and A. Sors, Eds.), IARC 

P.C. Jacquignon, E. Mastromatteo, J.P. Rigaut, 

C. Bishop, E. Buringh, W. Davis, M. Gounar, 

(F.W. Sunderman, Jr., A. itio, A.Berlin, 

to man. In Nickel in the Human Environment 

Bennet, B.G. (1984). Environmental nickel pathways 
106 Nickel Sulfate Hexahydrate, NTP TR 454 

340-347. 

to F344 rat lung. Fundam. Appl. Toxicol. 7, 

Comparative acute toxicity of four nickel compounds 

Hanson, R.L., and Rebar, A.H. (1986). 

Benson, J.M., Henderson, R.F., McClellan, R.O., 

12 days. Fundam. Appl. Toxicol. 9, 251-265. 

to F344/N rats and B6C3F, mice exposed for 

Comparative inhalation toxicity of nickel subsulfide 

Pickrell, J.A., and Dunnick, J.K. (1987). 

Haley, P.J., Hanson, R.L., Hobbs, C.H., 

Benson, J.M., Carpenter, R.L., Hahn, F.F., 

inhaled nickel compounds. Toxicology 57, 255-266. 

Biochemical responses of rat and mouse lung to 

Pickrell, J.A., and Dunnick, J.K. (1989). 

Haley, P.J., Henderson, R.F., Hobbs, C.H., 

Benson, J.M., Burt, D.G., Cheng, Y .S., Hahn, F.F., 

167-183. 

subsulfide in F344/N rats. Znhalat. Toxicol. 6, 

(1994). Fate of inhaled nickel oxide and nickel 

Hobbs, C.H., Kennedy, C.H., and Maples, K.R. 

Cheng, Y.-S., Dunnick, J.K., Eastin, W.E., 

Benson, J.M., Barr, E.B., Bechtold, W.E., 

pp. 153-164. Oxford University Press, Oxford. 

Ms.), IARC Scientific Publications No. 53, 

J.P. Rigaut, C. Rosenfeld, R. Saracci, and A. Sors, 

M. Gounar, P.C. Jacquignon, E. Mastromatteo, 

A. Berlin, C. Bishop, E. Buringh, W. Davis, 

Environment (F.W. Sunderman, Jr., A. Aitio, 

with tumour cells. In Nickel in the Human 

study of interaction of carcinogenic nickel compounds 

Galle, P., (1984). Electron microprobe in vitro 

Pot-Deprun, J., Dewally, D., Chouroulinkov, I., and 

Berry, J.P., Poupon, M.F., Judde, J.G., 

Salmonella tester strains. Mutat. Res. 175, 209-2 15. 

of the uptake and mutagenicity of nickel chloride in 

Biggart, N.W., and Costa, M. (1986). Assessment 

Publications, Park Ridge, NJ. 

E.K. Weisburger, Eds.), pp. 345-357. Noyes 

Handbook of Carcinogen Testing (H.A. Milman and 

pathology for rodent carcinogenicity studies. In 

Hardisty, J.F. (1985). Quality assurance in 

Eustis, S.L., Wolfe, M.J., McConnell, E.E., and 

Boorman, G.A., Montgomery, C.A., Jr., 

workers. Acta Otolaryngol. 97, 105- 1 15. 

concentration in plasma and urine in retired nickel 

changes, rhinoscopical findings and nickel 

Poppe, S., and Hsgetveit, A.C. (1984). Histological 

Boysen, M., Solberg, L.A., Torjussen, W., 

London. 

1932, pp. 103-104. His Majesty’s Stationery Office, 

inspector of factories and workshops for the year 

Bridge, J. C. (1 933). Annual report of the chief 

Publications, Oxford. 

Metabolism and Toxicology. Blackwell Scientific 

of the Third International Conference on Nickel 

(1985). Progress in Nickel Toxicology. Proceedings 

Brown, S.S., and Sunderman, F.W., Jr., Eds. 

pp. 87-101. Elsevier, New York. 

Transfer (G.L. Eichhorn and L.G. Marzili, Eds.), 

nucleus. In Metal Ions in Genetic Information 

Bryan, S.E. (1981). Heavy metals in the cell’s 

Environ. Contam. Toxicol. 11, 245-248. 

63NiC1, in the rat: Intratracheal study. Arch. 

Distribution and clearance of 63Ni administered as 

Carvalho, S.M.M., and Ziemer, P.L. (1982). 

19-36. 

categories. Environ. Mol. Mutagen. 12 (Suppl. 13), 

assay: Quality control guidelines and response 

of the L5178Y mouse lymphoma cell mutagenesis 

Mitchell, A.D., and Rudd, C.J. (1988). Evaluation 

Caspary, W.J., Lee, Y.J., Poulton, S., Myhr, B.C., 

Bingham, E., Barkley, W., Zenvas, M., Chashschin, V.P., Artunina, G.P., and Norseth, T. 

Stemmer, K., and Taylor, P. (1972). Responses of (1994). Congenital defects, abortion and other health 

alveolar macrophages to metals: I. Inhalation of lead effects in nickel refinery workers. Sci. Total 

and nickel. Arch. Environ. Health 25, 406-414. Environ. 148, 287-291. 
References 107 

Environ. Chem. 22, 51-59. 

nickel (11) with DNA damaging agents. Toxicol. 

Christie, N.T. (1989). The synergistic interaction of 

CRC Press, Boca Raton. 

(E.C. Foulkes, Ed.), Vol. 11, Chapter 4, pp. 95-128. 

carcinogenesis. In Biological Esfects of Heavy Metals 

Christie, N.T., and Katisifis, S.P. (1990). Nickel 

Biochem. 15D, 114. (Abstr.) 

on DNA replication by polymerase CY. J. Cell. 

Cohen, M. (1991). Kinetic analysis of Ni (11) effects 

Christie, N.T., Chin, Y .G., Snow, E.T., and 

Res. 42, 3544-3549. 

tissues by the carcinogen nickel carbonate. Cancer 

Nickel distribution and DNA lesions induced in rat 

Ciccarelli, R.B., and Wetterhahn, K.E. (1982). 

Code of Federal Regulations (CFR) 21, Part 58. 

6032-6038. 

Chinese hamster embryo cells. Cancer Res. 49, 

chromosomal alterations in nickel-transformed 

Conway, K., and Costa, M. (1989). Nonrandom 

nickel compounds. Crit. Rev. Toxicol. 4, 341-384. 

Costa, M. (1989). Toxicity and carcinogenicity of 

Coogan, T.P., Latta, D.M., Snow, E.T., and 

compounds. Biol. Trace Elem. Res. 5, 285-295. 

of transformation in cell culture by specific nickel 

Costa, M. (1983). Sequential events in the induction 

321-337. 

carcinogenesis. Annu. Rev. Pharmacol. Toxicol. 31, 

Costa, M. (1991). Molecular mechanisms of nickel 

metal compounds. Cancer Res. 43, 5652-5658. 

phagocytosis of potentially carcinogenic particulate 

surface charge and issolution on the selective 

Costa, M., and Heck, J.D. (1983). Influence of 

Eds.), pp. 43-46. Academic Press, London. 

Toxicology (S.S. Brown and F.W. Sunderman, Jr., 

related to their carcinogenic activity. In Nickel 

Phagocytosis of particulate nickel compounds is 

Costa, M., and Mollenhauer, H.H. (1980). 

42, 2757-2763. 

the induction of cellular transformation. Cancer Res. 

particles and DNA strand breaks as a mechanism for 

Selective phagocytosis of crystalline metal sulfide 

Costa, M., Heck, J.D., and Robison, S.H. (1982). 

J. Toxicol. Environ. Health 40, 217-222. 

biomvker of exposures experienced by welders. 

new assay for DNA-protein cross-links as a 

Toniolo, P. (1993). Preliminary report on a simple 

Costa, M., Zhitkovich, A., Taioli, E., and 

Environ. 148, 191-199. 

mechanisms of nickel carcinogenesis. Sci. Total 

Klein, C.B., and Salnikow, K. (1994). Molecular 

Costa, M., Zhuang, Z., Huang, X., Cosentino, S., 

Biochem. 46, 7-15. 

reduced oxygen species: An ESR study. J. Znorg. 

biologically important peptides in the presence of 

chemistry of complexes of nickel (11) with some 

Catteau, J.P., and HCnichart, J.P. (1992). Redox 

Cotelle, N., TrCmolih-es, E., Bernier, J.L., 

Sci. Total Environ. 148, 99-102. 

history of environmental degradation in Sudbury. 

Courtin, G.M. (1994). The last 150 years: A 

tables. J. R. Stat. Soc. B34, 187-220. 

Cox, D.R. (1972). Regression models and lifeInc., Princeton, NJ. 

Eds.), pp. 13-59. Princeton Scientific Publishing Co. 

(M.A. Mehlman, W.G. Flamm, and R.J. Lorentzen, 

Toxicity of Chemical Carcinogens and Mutagens 

Modern Environmental Toxicology: Mechanisms and 

mutation model of carcinogenesis. In Advances in 

Crawford, B.D. (1985). Perspectives on the somatic 

nickel subsulfide. Cancer Res. 38, 268-276. 

sarcomas in Fisher rats by intratesticular injection of 

and Allpass, P.R. (1978). Induction of testicular 

Damjanov, I., Sunderman, F.W., Jr., Mitchell, J.M., 

Br. J. Cancer 20, 886-895. 

response of rats to the injection of nickel sulphide. 

Daniel, M.R. (1966). Strain differences in the 
108 Nickel Sulfate Hexahydrate, NTP TR 454 

357-372. 

the drinking water. J. Toxicol. Environ. Health 24, 

in mice after long-term exposure to nickel sulfate in 

disposition, myelopoietic, and immunologic responses 

Boorman, G.A. (1988). Evaluation of tissue 

Luster, M.I., French, J.E., Hong, H.L., and 

Dieter, M.P., Jameson, C.W., Tucker, A.N., 

Toxicol. 6, 44-52. 

animal carcinogenicity experiments. Fundam. Appl. 

regression analysis of incidental-tumor data from 

Dinse, G.E., and Haseman, J.K. (1986). Logistic 

32, 236-248. 

analysis of tumour prevalence data. Appl. Statist., 

Dinse, G.E., and Lagakos, S.W. (1983). Regression 

nickel workers. Br. J. Znd. Med. 15, 217-223. 

Doll, R. (1958). Cancer of the lung and nose in 

University Press, Oxford. 

Scientific Publications No. 53, pp. 3-22. Oxford 

C. Rosenfeld, R. Saracci, and A. Sors, Eds.), IARC 

P.C. Jacquignon, E. Mastromatteo, J.P. Rigaut, 

C. Bishop, E. Buringh, W. Davis, M. Gounar, 

(F.W. Sunderman, Jr., A. Aitio, A. Berlin, 

hazard. In Nickel inthe Human Environment 

Doll, R. (1984). Nickel exposure: A human health 

man. Scand. J. Work Environ. Health 16, 1-82. 

international committee on nickel carcinogenesis in 

Weglo, J., and Wright, M. (1990). Report of the 

Sunderman, F.W., Jr., Thornhill, P., Warner, J.S., 

Seilkop, S.K., Shannon, H., Speizer, F., 

Norseth, T., Peto, J., Rigaut, J-P., Roberts, R., 

Enterline, P., Goldberg, M., Metcalfe, L., 

Cosmatos, I., Cragle, D.L., Easton, D., 

Doll, R., Andersen, A., Cooper, W.C., 

Appl. Pharmacol. 101, 220-231. 

the transfer of nickel through rat milk. Toxicol. 

chloride on lactating rats and their suckling pups, and 

Sunderman, F.W., Jr. (1989). Effects of nickel 

Dostal, L.A., Hopfer, S.M., Lin, S.-M., and 

sums. Technometrics 6. 24 1-252. 

Dunn, 0. J. (1964). Multiple comparisons using rank 

control. J. Am. Stat. Assoc. 50, 1096-1 121. 

procedure for comparing several treatments with a 

Dunnett, C. W. (1955). A multiple comparison 

584-594. 

rats and B6C3F, mice. Fundam. Appl. Toxicol. 12, 

subsulfide, or nickel sulfate hexahydrate in F344/N 

13-week inhalation exposure to nickel oxide, nickel 

and Eidson, A.F. (1989). Lung toxicity after 

Hobbs, C.H., Hahn, F.F., Haley, P.J., Cheng, Y.S., 

Dunnick, J.K., Elwell, M.R., Benson, J.M., 

7323-7328. 

ions on DNA helicity. J. Am. Chem. Soc. 90, 

compounds. XII. The relative effect of various metal 

of metal ions with polynucleotides and related 

Eichorn, G. L., and Shin, Y. A. (1968). Interaction 

486-492. 

insoluble form. Am. Znd. Hyg. Assoc. J. 42, 

after intratracheal administration of a soluble and 

Oberg, S.G. (1981). Toxicokinetics of nickel in rats 

English, J.C., Parker, R.D.R., Sharma, R.P., and 

925-933. 

manufacturing plant in West Virginia. JNCZ 68, 

among workers in a nickel refinery and alloy 

Enterline, P. E., and Marsh, G.M. (1982). Mortality 

Carcinogenesis. Technical Report No. 33. 

Epidemiology with Special Reference to 

Nickel Compounds: Review of Toxicology and 

European Chemical Industry (1989). Nickel and 

2729-2735. 

in cultured mammalian cells. Cancer Res. 42, 

intracellular fate of crystalline nickel sulfide particles 

Video time-lapse microscopy of phagocytosis and 

Evans, R.M., Davies, P.J.A., and Costa, M. (1982). 

J.F. Park, Eds.), pp. 219-233. Springer, New York. 

Carcinogenesis and Bioassays (E. Karbe and 

diethylnitrosamine. In Experimental Lung Cancer, 

of particulates on respiratory carcinogenesis by 

Farrell, R.L., and Davis, G.W. (1974). The effects 
References 109 

Environmental Protection Agency, Washington, DC. 

of toxicological profiles. Vol. 52, No. 74. U.S. 

toxicological profiles and guidelines for development 

of hazardous substances that will be the subject of 

Federal Register (1987). Notice of the first priority 

335-338. 

Res. Commun. Chem. Pathol. Pharmacol. 11, 

response of rats to immunization with T-1 phage. 

effect of nickel and chromium upon antibody 

Figoni, R.A., and Treagan, L. (1975). Inhibitory 

Environ. Res. 42, 83-93. 

intratracheally instilled Ni,S, and TiO, in mice. 

The pulmonary effects and clearance of

Finch, G.L., Fisher, G.L., and Hayes, T.L. (1987). 

313-320. 

nickel subsulfide on B6C3F, mice. Environ. Res. 40, 

(1986). Lifetime effects of inuatracheally instilled 

Fisher, G.L., Chrisp, C.E., and McNeill, D.A. 

42, 145-149. 

by DNA-protein cross-linking agents. Cancer Res. 

strand breaks produced during the repair of damage 

Fornace, A. J., Jr . (1982). Detection of DNA singlePharmacol. Soc. 14, 68-71. 

as a model for metal carcinogenesis. Proc. West. 

Furst, A., and Schlauder, M. C. (197 1). The hamster 

957-974. 

tests for carcinogenicity. J. Natl. Cancer Inst. 62, 

Statistical issues in interpretation of chronic bioassay 

Gart, J. J., Chu, K.C., and Tarone, R.E. (1979). 

Arch. Environ. Contam. Toxicol. 9, 17-22. 

abnormalities in nickel poisoning in chick embryos. 

Gild, S.H., and Marano, M. (1980). Congenital 

158-162. 

iron, and nickel compounds. Cancer Res. 22, 

study on the carcinogenic activity of cobalt, copper,, 

Gilman, J.P.W. (1962). Metal carcinogenesis. 11. A 

Can. Cancer Con$ 6, 209-223. 

Gilman, J.P.W. (1966). Muscle tumourigenesis. 

Cancrum 19, 615-619. 

tumourigenesis in the rat. Acta Unio Int. Contra 

of physical form of implant on nickel sulphide 

Gilman, J.P.W., and Herchen, H. (1963). The effect 

Excelpta Med. Int. Congr. Sci. 676, 325-328. 

with NiO and As,O, aerosols in Wistar rats. 

Takenake, S. (1986). Long-term inhalation studies 

Glaser, U., Hochrainer, D., Oldiges, H., and 

Caledonia. Cancer Causes Control 5, 15-25. 

nickel mining and refining workers in New 

cancer and a case-control study within a cohort of 

(1994). A IO-year incidence survey of respiratory 

Chastang, J.-F., Marne, M.-J., and Dubourdieu, D. 

Goldberg, M., Goldberg, P., Leclerc, A., 

spleen. Environ. Health Perspect. 12, 109-1 13. 

nickel chloride on primary antibody production in the 

Daniels, M.J., and Coffin, D.L. (1975a). Effect of 

Graham, J.A., Gardner, D.E., Miller, F.J., 

Immun. 11, 1278-1283. 

phagocytosis byalveolar macrophages. Infect. 

Coffin, D.L. (1975b). Effect of trace metals on 

Graham, J.A., Gudner, D.E., Waters, M.D., and 

immunity in mice. Environ. Res. 16, 77-87. 

of cadmium, nickel, and chromium on primary 

Payne, E.A., and Gardner, D.E. (1978). Influence 

Graham, J.A., Miller, F.J., Daniels, M.J., 

University Press, Oxford. 

Scientific Publications No. 53, pp. 469-486. Oxford 

C. Rosenfeld, R. Saracci, and A. Sors, Eds.), IARC 

P.C. Jacquignon, E. Mastromatteo, J.P. Rigaut, 

C. Bishop, E. Buringh, W. Davis, M. Gounar, 

(F.W. Sunderman, Jr., A. Aitio, A. Berlin, 

In Nickel in the Human Environment 

Grandjean, P. (1984). Human exposure to nickel. 

Pharmacol. 88, 1-12. 

primate pulmonary immune system. Toxicol. Appl. 

Immunopathologic effects of nickel subsulfide on the 

Hahn, F.F., and Benjamin, S.A. (1987). 

Haley, P.J., Bice, D.E., Muggenburg, B.A., 
110 Nickel Sulfate Hexahydrate, NTP TR 454 

Appl. Toxicol. 15, 476-487. 

13-week inhalation exposure in the mouse. Fundam. 

immunotoxicity of three nickel compounds following 

Dunnick, J.K., and Hobbs, C.H. (1990). The 

Cheng, Y.-S., Bice, D.E., Luster, M.I., 

Haley, P.J., Shopp, G.M., Benson, J.M., 

4045-405 1. 

repair in mammalian cells. Cancer Res. 54, 

interferes with the incision step in nucleotide excision 

Kasten, U., and Beyersmann, D. (1994). Nickel (11) 

Hartwig, A., Mullenders, L.H.F., Schepegrell, R., 

58, 385-392. 

carcinogenicity studies. Environ. Health Perspect. 

design, analysis and interpretation of animal 

Haseman, J.K. (1984). Statistical issues in the 

studies in rodents. Toxicol. Pathol. 12, 126- 135. 

Use of historical control data in carcinogenicity 

Haseman, J.K., Huff, J., and Boorman, G. A. (1984). 

75, 975-984. 

(C57BW6N X C3H/HeN)Fl (B6C3Fl) mice. JNCl 

control groups of F344/N rats and

Neoplasms observed in untreated and corn oil gavage 

Boorman, G.A., and McConnell, E.E. (1985). 

Haseman, J.K., Huff, J.E., Rao, G.N., Arnold, J. E., 

in vitro. Arch. Toxicol. (Suppl. 4), 143-147. 

and other chemicals on macrophages and thymocytes 

technique of testing for the influence of metal salts 

Hennighausen, G., and Lange, P. (1980). A simple 

tumorigenesis. Nature 202, 306-307. (Abstr.) 

duration of exposure on nickel sulphide 

Herchen, H., and Gilman, J.P.W. (1964). Effect of 

ultrastructural study. Cancer 43, 1358-1374. 

skeletal muscle. A light microscopical and

sub-sulphide-induced leiomyosarcoma in rabbit white 

Hildebrand, H.F., and Biserte, G. (1979a). Nickel 

Biol. 19, 276-280. 

induced rhabdomyosarcoma in rabbits. Eur. J. Cell 

Cylindrical laminated bodies in nickel-subsulphideHildebrand, H.F., and Biserte, G. (1979b). 

Conference, 259-264. 

Physical and Chemical Properties of Aerosols, Eighth 

Aerosols in Science, Medicine, and Technology: 

lung clearance of Ni and its effect on lung function. 

(1980). Generation of NiO aerosols for studying 

Hochrainer, D., Oberdoerster, G., and Mihm, U. 

113-120. 

exposure in nickel refining. Ann. Occup. Hyg. 21, 

(1978). Plasma nickel as a primary index of 

Hragetveit, A.C., Barton, R.T., and Kostral, C.O. 

John Wiley and Sons, New York. 

Nonparametric Statistical Methods, pp . 120- 123. 

Hollander, M., and Wolfe, D.A. (1973). 

Elem. Res. 7, 223-239. 

caused by inhalation of nickel oxide. Biol. Trace 

findings with special reference to cancer in rats 

and Tsuchiya, K. (1985). Electron microscopical 

Horie, A., Haratake, J., Tanaka, I., Kodama, Y., 

Carcinogenesis 1, 297-304. 

[3H] thymidine into DNA in rat liver and kidney. 

of nickel ompounds on incorporation of 

Hui, G., and Sunderman, F. W., Jr. (1980). Effects 

Biophys. Res. Commun. 159, 445-451. 

complex of glycylglycyl-L-histidine. Biochem. 

produced from hydrogen peroxide and nickel (11) 

for superoxide, hydroxyl radicals and singlet oxygen 

Inoue, S., and Kawanishi, S. (1989). ESR evidence 

France. 

Anaesthetics, Vol. 11, pp. 75-112. IARC, Lyon, 

Chemicals and General Considerations on Volatile 

Nickel, Some Epoxides, Miscellaneous Industrial 

Carcinogenic Risk of Chemicals to Man: Cadmium, 

(1976). IARC Monographs on the Evaluation of the 

International Agency for Research on Cancer (IARC) 
References 111 

France. 

Founding, Vol. 34, pp. 133-190. IARC, Lyon, 

Gasification, Coke Production, and Iron and Steel 

Exposures in Aluminium Production, Coal 

Polynuclear Aromatic Compounds, Part 3, Industrial 

Carcinogenic Risk of Chemicals to Humans: 

(1984). IARC Monographs on the Evaluation of the 

International Agency for Research on Cancer (IARC) 

pp. 264-269. IARC, Lyon, France. 

Monographs Volumes 1 to 42 (Suppl. 7), 

of Carcinogenicity: An Updating of IARC 

Carcinogenic Risks to Humans. Overall Evaluations 

(1987). IARC Monographs on the Evaluation of 

International Agency for Research on Cancer (IARC) 

and Welding, Vol. 49. IARC, Lyon, France. 

Carcinogenic Risks to Humans: Chromium, Nickel 

(1990). IARC Monographs on the Evaluation of 

International Agency for Research on Cancer (IARC) 

35, 71-78. 

intrarenal injection of nickel subsulfide. Lab. Invest. 

carcinomas and erythrocytosis in rats following 

Jasmin, G., and Riopelle, J.L. (1976). Renal 

41, 133-145. 

k-sample test against ordered alternatives. Biometrika 

Jonckheere, A.R. (1954). A distribution-free 

78, 1185-1 190. 

compounds: Preventive action of manganese. JNCI 

rat natural killer cell function by carcinogenic nickel 

Poupon, M.F., and Jasmin, C. (1987). Inhibition of 

Judde, J.G., Breillout, F., Clemenceau, C., 

compounds. Mutat. Res. 77, 109-116. 

Rec assay nd mutagenicity studies on metal 

Kanematsu, N., Hara, M., and Kada, T. (1980). 

Stat. Assoc. 53. 457-481. 

estimation from incomplete observations. J. Am. 

Kaplan, E.L., and Meier, P. (1958). Nonparametric 

in vitro dissolution rates. Carcinogenesis 4,275-279. 

nickel(I1)sulfate in Wistar rats and its relation to the 

(1983). Carcinogenicity of nickel(I1)hydroxides and 

Kasprzak, K.S., Gabryel, P., and Jarczewska, K. 

55, 2210-2218. 

Principles of environmental analysis. Anal. Chem. 

Libby, R.A., Taylor, J.K., and Wentler, G. (1983). 

Keith, L.H., Crummett, W., Degan, J., Jr., 

Possible epigenetic control. Science 251, 796-799. 

nickel-transformed cells by an X chromosome: 

Barrett, J.C., and Costa, M. (1991). Senescence of 

Bhamra, R.K., Lin, X., Cohen, M.D., Annab, L., 

Klein, C.B., Conway, K., Wang, X.W., 

Biol. Trace Elem. Res. 7, 1-9. 

clearance of a nickel oxide aerosol by inhalation. 

and Tsuchiya, K. (1985). Pulmonary deposition and 

Kodama, Y., Ishimatsu, S., Matsuno, K., Tanaka, I., 

Environ. Mutagen. 3, 597-606. 

aberrations in human and Syrian hamster cell strains. 

salts of sister chromatid exchanges and chromosome 

DiPaolo, J. A. (1 98 1). Induction by inorganic metal 

Larramendy, M.L:, Popescu, N.C., and 

carbonyl in rats. Cancer Res. 32, 2253-2258. 

( 1972). The carcinogenicity of intravenous nickel 

Lau, T.J., Hackett, R.L., and Sunderman, F.W., Jr. 

Toxicol. Appl. Pharmacol. 57, 439-45 1, 

metals on primary humoral immune responses. 

lymphocyte activities. I. In vitro effects of heavy 

Lawrence, D. A. (1981). Heavy metal modulation of 

acid and protein. Biochemistry 21, 771-778. 

subsulfide and its interaction with deoxyribonucleic 

(1982). Solubilization of the carcinogen nickel 

Lee, J.E., Ciccarelli, R.B., and Jennette, K.W. 

Mutat. Res. 300, 63-72. 

xanthine-guanine phosphoribosyl transferase locus. compounds at the gpt locus in G12 Chinese hamster 

sulfides in Chinese hamster V79 cell lines atthe Mutagenicity of soluble and insoluble nickel 

Mutagenic responses ofnickel oxides and nickel Rossman, T.G., and Christie, N.T. (1993). 

Kargacin, B., Klein, C.B., and Costa, M. (1993). Lee, Y .W., Pons, C., Tummolo, D.M., Klein, C.B., 

cells. Environ. Mol. Mutagen. 21, 365-371. 
112 Nickel Sulfate Hexahydrate, Nl" TR 454 

University Press, Oxford. 

Publications No. 53, pp. 277-292. Oxford 

R. Saracci, and A. Sors, Ms.), IARC Scientific 

E. Mastromatteo, J.P. Rigaut, C. Rosenfeld, 

W. Davis, M. Gounar, P.C. Jacquignon, 

A. Aitio, A. Berlin, C. Bishop, E. Buringh, 

in the Human Environment (F. W. Sunderman, Jr., 

Embryotoxicity and genotoxicity of nickel. In Nickel 

Leonard, A., and Jacquet, P.(1984). 

nickel. Chem. Biol. Interact. 79, 217-228. 

2'-deoxyguanosine in the presence of magnesium and 

( 199 1). Hydroxylation and eglycosylation of 

Littlefield, N.A., Fullerton, F.R., and Poirier, L.A. 

carcinogenesis studies. JNCZ 76, 283-289. 

combining neoplasms for evaluation of rodent 

and Boorman, G.A. (1986). Guidelines for 

McConnell, E.E., Solleveld, H.A., Swenberg, J.A., 

Mutagen. 12, 85-154. 

assay: 111. 72 coded chemicals, Environ. Mol. 

tk+/tk- mouse lymphoma cell forward mutation 

Caspary, W. J. (1988). Responses of the L5 178Y 

Edwards, I., McBride, D., Riach, C., and 

McGregor, D.B., Brown, A., Cattanach, P., 

148, 109-138. 

in the terrestrial environment. Sci. Total Environ. 

McIlveen, W.D., and Negusanti, J.J. (1994). Nickel 

639-648. 

carcinogenesis experiments. J. Am. Stat. Assoc. 79, 

differences in tumor incidence based on animal 

McKnight, B., and Crowley, J. (1984). Tests for 

safety assessment. Toxicol. Pathol. 10, 71-80. 

alterations and hepatocellular tumors in chemical 

Interpretation of rodent hepatocellular proliferative 

Maronpot, R.R., and Boorman, G.A. (1982). 

Toxicology 35, 47-57. 

toxicity and teratogenicity of nickel in pregnant rats. 

Mas, A., Holt, D., and Webb, M. (1985). The acute 

Environ. Physiol. Biochem. 2, 137-141. 

Mason, M.M. (1972). Nickel sulfide carcinogenesis. 

105-1 13. 

cytogenetic changes in poisoned rats. Toxicology 10, 

Tandon, S.K. (1978). Distribution of nickel and 

Mathur, A.K., Dikshith, T.S.S., Lal, M.M., and 

sulfate solutions. Environ. Res. 43, 168-178. 

F344/N rats after intratracheal instillation of nickel 

(1987). Lung clearance and disposition of 63Ni in 

Medinsky, M.A., Benson, J.M., and Hobbs, C.H. 

Ed.), p. 1028. Merck and Company, Rahway, NJ. 

The Merck Index (1989). 11th ed. (S. Budavari, 

zinc and nickel. J. Submicrosc. Cytol. 14, 621 -626. 

alveolar macrophages in rats exposed to oxides of 

Zambernard, J. (1982). Changes in pulmonary 

Migally, N., Murthy, R.C., Doye, A., and 

Spring Harbor, NY. 

pp. 605-627. Cold Spring Harbor Laboratory, Cold 

(H.H. Hiatt, J.D. Watson, and J.A. Winsten, Eds.), 

electrophiles. In Origins of Human Cancer 

chemical carcinogens as reactive mutagenic 

Miller, J.A., and Miller, E.C. (1977). Ultimate 

compounds. Environ. Mol. Mutagen. 14, 65-78. 

embryo cells by insoluble carcinogenic nickel 

neoplastic transformation of C3H/ 1 OT1/2 C1 8 mouse 

Landolph, J.R. (1989). Morphological and 

Miura, T., Patierno, S.R., Sakuramoto, T., and 

Br. J. Ind. Med. 15, 224-234. 

incidence of respiratory cancer in nickel workers. 

Morgan, J.G. (1958). Some observations on the 

University Press, Oxford. 

Publications No. 53, pp. 507-520. Oxford 

R. Saracci, and A. Sors, Eds.), IARC Scientific 

E. Mastromatteo, J.P. Rigaut, C. Rosenfeld, 

W. Davis, M. Gounar, P.C. Jacquignon, 

A. Aitio, A. Berlin, C. Bishop, E. Buringh, 

the Human Environment (F. W. Sunderman, Jr., 

monitoring in nickel refinery workers. In Nickel in 

Morgan, L. G., and Rouge, P. J.C. (1 984). Biological 
References 113 

cells. Mutat. Res. 261, 131-137. 

and cobalt compounds in cultured mouse FM3A 

Mutagenicity of various chemicals including nickel 

Morita, H., Umeda, M., and Ogawa, H. I. (1991). 

Company, New York. 

Methods, 2nd ed., pp. 170-179. McGraw-Hill Book 

Morrison, D. F. ( 1976). Multivariate Statistical 

pp. 467-479. John Wiley and Sons, Inc., New York. 

Perspectives (E. Nieboer and J.O. Nriagu, Eds.), 

hamsters. In Nickel and Human Health: Current 

intratracheally instilled nickel-containing particles in 

Mohr, U., and Pott, F. (1992). Chronic effects of 

Muhle, H., Bellmann, B., Takenaka, S., Fuhst, R., 

workers (1993). Br. J. Zndust. Med. 50, 428-431. 

opacities in chest radiographs of nickel sinter plant 

Morgan, W.K.C. (1993). Prevalence of small 

Roos, J., Chan, J., Maehle, W., and 

Muir, D.C.F., Julian, F., Jadon, N., Roberts, R., 

51, 19-22. 

from sinter plant exposure. Occup. Environ. Med. 

in nickel sinter plant workers: Effect of removal 

Roberts, R.S. (1 994). Cancer of the respiratory tract 

Muir, D.C.F., Jadon, N., Julian, J.A., and 

J. Submicrosc. Cytol. 15, 655-660. 

rats exposed to nickel oxide by inhalation. 

Ultrastructural changes in alveolar macrophages of 

Murthy, R.C., and Niklowitz, W.J. (1983). 

Pollutants, Nickel. Washington, DC. 

Medical and Biological Effects of Environmental 

National Academy of Sciences (NAS) (1975). 

Institutes of Health, Bethesda, MD. 

and Welfare, , Public Health Service, National 

No. 76-801. U.S. Department of Health, Education, 

Technical Report Series No. 1. NIH Publication 

for Carcinogen Bioassay in Small Rodents. 

National Cancer Institute (NCI) (1976). Guidelines 

Welfare Publication No. 77-164. 

Nickel. Department ofHealth, Education, and 

Standard: Occupational Exposure to Inorganic 

(NIOSH) (1977). Criteria for a Recommended 

National Institute for Occupational Safety and Health 

of January 1, 1991. Cincinnati, OH. 

Survey (198 1 - 1983), unpublished provisional data as 

(NIOSH) ( 199 1). National Occupational Exposure 

National Institute for Occupational Safety and Health 

Service, National Institutes of Health, Bethesda, MD. 

Health, Education, and Welfare, Public Health 

Specification NIH-11-1335. U.S. Department of 

Formula Mouse and Rat Ration (NIH-07). 

National Institutes of Health (NIH) (1978). Open 

NC . National Institutes of Health, Research Triangle Park, 

Health and Human Services, Public Health Service, 

Toxicity Report Series No. 39. U.S. Department of 

by Inhalation to F344/N Rats and B6C3F, Mice. 

Cadmium Oxide (CAS No. 1306- 19-0) Administered 

Technical Report on the Toxicity Studies of 

National Toxicology Program (NTP) (1995). 

Research Triangle Park, NC. 

Health Service, National Institutes of Health, 

Department of Health and Human Services, Public 

No. 451. NIH Publication No. 96-3367. U.S. 

Mice (Inhalation Studies). Technical Report Series 

(CAS No. 1313-99-1) in F344/N Rats and B6C3Fl 

Carcinogenesis Studies of Nickel Oxide 

Technical Report on the Toxicology and 

National Toxicology Program (NTP) ( 1996a). 

Research Triangle Park, NC). 

Health Service, National Institutes of Health, 

Department of Health and Human Services, Public 

No. 453. NIH Publication No. 96-3369. U.S. 

Mice (Inhalation Studies). Technical Report Series 

(CAS No. 12035-72-2) in F344/N Rats and B6C3Fl 

Carcinogenesis Studies of Nickel Subsulfide 

Technical Report on the Toxicology and 

National Toxicology Program (NTP) ( 1996b). 

respiratory tract. Eur. Respir. J. 3, 202-2 19. 

Nemery, B. (1 990). Metal toxicity and the 

John Wiley and Sons, Inc., New York. 

(E. Nieboer and J.O. Nriagu, Eds.), pp. 239-259. 

and Human Health: Current Perspectives 

the immune system: Current concepts. In Nickel 

Nicklin, S., and Nielsen, G.D. (1992). Nickel and 
114 Nickel Sulfate Hexahydrate, NTP TR 454 

John Wiley and Sons, Inc., New York. 

and Human Health: Current Perspectives. 

Nieboer, E., and Nriagu, J. O., Eds. (1992). Nickel 

ecological issues. Sci. Total Environ. 148. 

Special Issue: Nickel biochemistry, toxicology, and 

Nieboer, E., and Templeton, D.M., Eds. (1994). 

Trace Elem. Res. 21. 23-33. 

induced structural changes in synthetic DNA. Biol. 

nickel(I1)-oligopeptide complexes and nickel(I1)- 

with hydrogen peroxide of histidine-containing 

Superoxide dismutase activity and novel reactions 

Nieboer, E., Tom, R.T., and Rossetto, F.E. (1989). 

21, 236-243. 

the y-emitting isotope "Ni. Fundam. Appl. Toxicol. 

(1993). Toxicokinetics of nickel in mice studied with 

Nielsen, G.D., Andersen, O., and Jensen, M. 

cells by nickel compounds. Mutat. Res. 68, 337-349. 

of chromosomal aberrations in cultured mammalian 

Nishimura, M., and Umeda, M. (1979). Induction 

Total Environ. 148, 103-108. 

nickel smelters in the Kola Peninsula (Russia). Sci. 

Norseth, T. (1994). Environmental pollution around 

metal ions. Mutat. Res. 104, 141-145. 

Inducibility of sister-chromatid exchanges by heavyOhno, H., Hanaoka, F., and Yamada, M. (1982). 

Cynops pyrrhogaster. Cancer Res. 47, 52 13-52 17. 

nickel subsulfide in the Japanese common newt, 

Okamoto, M. (1987). Induction of ocular tumor by 

Toxicology 12, 165- 172. 

autoradiography of 63Ni n mice throughout gestation. 

Olsen, I., and Jonsen, J. (1979). Whole-body 

in mice. Ann. Clin. Lab. Sci. 9, 47-59. 

autoradiographic study on the distribution of 63NiC1, 

Oskarsson, A., and Tjalve, H. (1979). An 

powder diffraction. Cancer Res. 39, 4175-4182. 

carcinogenesis studied by autoradiography and X-ray 

(1979). Fate of nickel subsulfide during 

Oskarsson, A., Andersson, Y., and Tjdve, H. 

Chem. 9, 45-50. 

stability of some metal sulfates. J. Znorg. Nucl. 

Ostroff, A.G., and Sanderson, R.T. (1959). Thermal 

1165-1 170. 

carcinogenesis of rats. J. Natl. Cancer Znst. 54, 

Inhalation studies of nickel sulfide in pulmonary 

Falk, H.L., and MacFarland, H.N. (1975). 

Ottolenghi, A.D., Haseman, J.K., Payne, W.W., 

75-91. 

cultured mammalian cells. Chem. Biol. Interact. 55, 

cross-links induced by nickel compounds in intact 

Patierno, S.R., and Costa, M. (1985). DNA-protein 

by metal salts. Mutat. Res. 16, 332-336. 

Chromosome damage in human cell cultures induced 

Paton, G.R., and Allison, A.C. (1972). 

Assoc. Cancer Res. 5, 50. (Abstr.) 

compounds in experimental animals. Proc. Am. 

Payne, W. W. (1964). Carcinogenicity of nickel 

pp. 37-46. Oxford University Press, Oxford. 

Ms.), IARC Scientific Publications No. 53, 

J.P. Rigaut, C. Rosenfeld, R. Saracci, and A. Sors, 

M. Gounar, P.C. Jacquignon, E. Mastromatteo, 

A. Berlin, C. Bishop, E. Buringh, W. Davis, 

Human Environment (F.W. Sunderman, Jr., A. Aitio, 

of Welsh nickel refinery workers. In Nickel in the 

Morgan, L.G. (1984). Respiratory cancer mortality 

Peto, J., Cuckle, H., Doll, R., Hermon, C., and 

Cancer Res. 44, 1520-1522. 

acetate-induced lung tumors in strain A mice. 

calcium acetates of lead subacetate- and nickel 

Shimkin, M . B . ( 1984). Inhibition by magnesium and 

Poirier, L.A., Theiss, J.C., Arnold, L.J., and 

Zbl. Hyg. 193, 140-149. 

measuring DNA damage by genotoxic substances. 

(1992). Experiences with the alkaline filter elution in 

Muller, G., Schmieding, W., and Norpoth, K. 

Popp, W., Vahrenholz, C., Goch, S., Muller, C., 

dusts in rats. Exp. Pathol. 32, 129-152. 

studies on fibres, metal compounds, and some other 

Ernst, H., and Mohr, U. (1987). Carcinogenicity 

Pott, F., Ziem, U., Reiffer, F.-J., Huth, F., 
References 115 

Consultants, Edinburgh. 

(J.-P. Vernet, Ed.), Vol. 2, pp. 127-129. CEP 

the Environment: International Cference 

injection of nickel compounds. In Heavy Metals in 

the abdominal cavity of rats after intraperitoneal 

Rosenbruch, M., and Huth, F. (1 989). Tumours in 

Pott, F., Rippe, R.M., Roller, M., Csicsaky, M., 

John Wiley and Sons, Inc., New York. 

(E. Nieboer and J.O. Nriagu, Eds.), pp. 491-502. 

and Human Health: Current Perspectives 

alloys in rats by intraperitoneal injection. In Nickel 

Carcinogenicity of nickel compounds and nickel 

Rosenbruch, M., and Huth, F. (1992). 

Pott, F., Rippe, R.M., Roller, M., Csicsaky, M., 

studies. Am. J. Clin. Nutr. 45, 252-260. 

spontaneous tumors in rats and mice of long-term 

(1987). Influence of body weight on the incidence of 

Rao, G.N., Piegorsch, W.W., and Haseman, J.K. 

National Institute for Occupational Safety and Health. 

Health Service, Centers for Disease Control, 

Department of Health and Human Services, Public 

(RTECS) (1987). Vol. 3A (D.V. Sweet, Ed.) U.S. 

Registry of Toxic Effects of Chemical Substances 

Toxicol. Ind. Health 5. 957-974. 

I. Methodology and mortality by major cause groups. 

the mining, smelting, and refining of nickel: 

(1989a). A study of mortality in workers engaged in 

Muir, D.C.F., Shannon, H.S., and Mastromatteo, E. 

Roberts, R.S., Julian, J.A., Sweezey, D., 

975-993. 

respiratory tract and kidney. Toxicol. Ind. Health 5, 

refining of nickel: 11. Mortality from cancer of the 

workers engaged in the mining, smelting, and 

Shannon, H .S. ( 1989b). A study of mortality in 

Roberts, R.S., Julian, J.A., Muir, D.C.F., and 

Carcinogenesis 3, 657-662. 

DNA induced by specific metal compounds. 

Strand breakage and decreased molecular weight of 

Robison, S.H., Cantoni, O., and Costa, M. (1982). 

mammalian cells. Cancer Lett. 17, 273-279. 

compounds induce DNA repair synthesis in cultured 

Costa, M. (1983). Soluble and insoluble nickel 

Robison, S.H., Cantoni, O., Heck, J.D., and 

melanogaster. Mutat. Res. 170, 115-1 17. 

Mutagenicity of nickel sulphate inDrosophila 

Rodriguez-Arnaiz, R., and Ramos, P.M. (1986). 

mutations. Sci. Total Environ. 148, 201-206. 

( 1994). Characterization of nickel-induced 

Rossetto, F.E., Turnbull, J.D., and Nieboer, E. 

Research Laboratories, Philadelphia, PA. 

Sadtler Standard Spectra. IR No. 6342K. Sadtler 

Cancer Res. 41, 4136-4139. 

exchange in human lymphocytes by nickel subsulfide. 

C3H/10T1h cells and increased sister chromatid 

Oncogenic transformation and celllysis in 

Saxholm, H. J.K., Reith, A., and Brergger, A. (198 1). 

other trace metals on mice. J. Nutr. 105, 452-458. 

term effects of mercury, methyl mercury, and nine 

Schroeder, H.A., and,Mitchener, M. (1975). Lifetissue levels. J. Nutr. 83, 239-250. 

titanium in mice: Effect on mortality, tumors and 

Jr. (1964). Chromium, lead, cadmium, nickel, and 

Schroeder, H.A., Balassa, J.J., and Vinton, W.H., 

DNA. Toxicol. Appl. Pharmacol. 84, 278-285. 

uptake influences its interaction witheterochromatic 

Sen, P., and Costa, M. (1986a). Pathway of nickel 

1527-1533. 

nickel and chromium compounds. Carcinogenesis 7, 

localization of sister chromatid exchanges induced by 

Sen, P., and Costa, M. (1986b). Incidence and 

compounds. Cancer Res. 47, 2142-2147. 

damage induced by calcium chromate and nickel 

Comparison of the localization of chromosome 

Sen, P., Conway, K., and Costa, M. (1987). 

hydroperoxides. J. Inorg. Biochem. 15, 2 1 1-225. 

complexes with molecular oxygen and model lipid 

Generation of free radicals in reactions of Ni(I1)-thiol 

Shi, X., Dalal, N.S., and Kasprzak, K.S. (1993). 
116 Nickel Sulfate Hexahydrate, NTP TR 454 

sulphide (Ni3S2). J. Pathol. 157, 263-274. 

articular, and retroperitoneal injection of nickel rats. Ecotoxicol. Environ. Safety 8, 516-525. 

in F344 rats by subcutaneous, intramuscular, intra- macrophages and the humoral immune systems of 

Otsuka, H. (1989). Induction of soft tissue tumours (1984). Effects of NiO inhalation on alveolar 

Shibata, M., Izumi, K., Sano, N., Akagi, A., and Spiegelberg, T., Kordel, W., and Hochrainer, D. 

of a treatment. Biometrics 33, 386-389. 

Williams’ test for contrasting increasing dose levels 

Shirley, E. (1977). A non-parametric equivalent of 

pulmonary tumor response in strain A mice. Cancer 

carcinogenicity ofmetallic compounds by the 

Thompson, T.L., and Terry, L.S. (1976). Test for 

Stoner, G.D., Shimkin, M.B., Troxell, M.C., 

Blackwell Scientific Publications, Oxford. 

and F.W. Sunderman, Jr., Eds.), pp. 37-40. 233-241. 

oxide. In Progress in Nickel Toxicology (S.S. Brown differentiation, and cancer causation. JNCZ 67, 

intrapleural injection of nickel subsulphide and nickel Straus, D.S. (1981). Somatic mutation, cellular 

Norseth, T. (1985). Tumor induction in rats after 

Skaug, V., Gylseth, B., Reiss, A.-L.P., and Res. 36, 1744-1747.- 

Environ. Res. 33, 413-427. 

I. Suppression of cellular and humoral immunity. 

Stott, G.A. (1984). Immunologic effects of nickel: 

Smialowicz, R.J., Rogers, R.R., Riddle, M.M., and 

Environ. Res. 36, 56-66. 

11. Suppression of natural killer cell activity. 

(1985). Immunologic effects of nickel: 

Garner, R.J., Rowe, D.G., and Luebke, R.W. 

Smialowicz, R.J., Rogers, R.R., Riddle, M.M., 

exposure to NiC1,. Toxicology 38, 293-303. 

Immunological studies in mice following in utero 

Rowe, D.G., and Luebke, R.W. (1986). 

Smialowicz, R.J., Rogers, R.R., Riddle, M.M., 

1-22. 

in metal-induced damage. Cell Biol. Toxicol. 10, 

Sugiyama, M. (1994). Role of cellular antioxidants 

131-141. 

nickel carcinogenesis. Environ. Health Perspect. 40, 

Sunderman, F.W., Jr. (1981). Recent research on 

York. 

J.M. Rice, Eds.), pp. 107-126. Plenum Press, New 

Carcinogenesis’ (R. Langenbach, S. Nesnow, and 

Organ and Species Specificity in Chemical 

specificity in nickel subsulfide carcinogenesis. In 

Sunderman, F.W., Jr. (1983a). Organ and species 

Environ. Res. 61, 200-21 1. 

toxicity associated with nickel chloride exposure. Ann. Clin. Lab. Sci. 13, 1-4. 

Feng, H.A., and Kimmel, G.L. (1993). Perinatal from nickel contamination of intravenous fluids. 

Smith, M.K., George, E.L., Stober, J.A., Sunderman, F.W., Jr. (1983b). Potential toxicity 

Mutagen. 8, 621-626. 

nickel dusts in a particle feeding ciliate. Environ. 

and Fisher, G.L. (1986). Bioassay of environmental 

Smith-Sonneborn, J., Leibovitz, B., Donathan, R., 

M. Gounar, P.C. Jacquignon, E. Mastromatteo, 

A. Berlin, C. Bishop, E. Buringh, W. Davis, 

Human Environment (F.W. Sunderman, Jr., A. Aitio, 

nickel compounds in animals. In Nickel in the 

Sunderman, F. W., Jr. (1984). Carcinogenicity of 

Snow, E.T. (1992). Metal carcinogenesis: 

Mechanistic implications. Pharmacol. Ther. 53, pp. 127-142. Oxford University press, Oxford. 

Eds.), IARC Scientific Publications No. 53, 

J.P. Rigaut, C. Rosenfeld,-R. Saracci, and A. Sors, 

31-65. 

Sosinski, E. (1975). Morphological changes in rat Sunderman, F.W., Jr. (1989). Mechanistic aspects 

brain and skeletal muscle in the region of nickel of nickel carcinogenicity. Arch. Toxicol. (Suppl. 13), 

oxide implantation. Neuropatol. Pol. 13, 479-483. 40-47. 
References 117 

New York. 

Eds.), pp. 69-76. John Wiley and Sons, Inc., rats by intrarenal injection of nickel subsulfide. 

Current Perspectives (E. Nieboer and J.O. Nriagu, Damjanov, I. (1979). Induction of renal cancers in 

nickel in humans. In Nickel and Human Health: Hopfer, S.M., Mitchell, J.M., Allpass, P.R., and 

Sunderman, F.W., Jr.(1992). Toxicokinetics of Sunderman, F.W., Jr., Maenza, R.M., 

J. Environ. Pathol. Toxicol. 2, 1511-1527. 

Pharmacol. 31, 545-554. Invest. 1 , 469-474. 

Fischer rats. Res. Commun. Chem. Pathol. antimonide, and nickel telluride in rats. Cancer 

Carcinogenesis tests of nickel arsenides, nickel Sunderman' Jr" and McCully' K.S' (1983)' transplacental carcinogenicity of nickel subsulfide in 

Rinehimer, L. A. (198 1). Negative test for 

Pharmacol. 14, 319-330. 

compounds in rats. Res. Commun. Chem. Pathol. 

Comparisons of carcinogenicities of nickel 

Sunderman, F. W., Jr., and Maenza, R.M. (1976). 

Verlagsgesellschaft, New York. 

Environment (E. Merian, Ed.), pp. 1101-1 126. VCH 

Nickel. In Metals and Their Compounds in the 

Sunderman, F. W., Jr., and Oskarsson, A. (1991). 

480-485. 

one year observation. Arch. Environ. Health 16, 

exposure of rats to nickel carbonyl: A report after 

and West, B. (1957). Nickel poisoning. IV. Chronic 

Sunderman, F.W., Kincaid, J.F., Donnelly, A.J., 

carbonyl. A.M. A. Arch. Znd. Health 20, 36-41. 

IX. Carcinogenesis in rats exposed to nickel 

Kincaid, J.F. (1959). Nickel poisoning: 

Sunderman, F.W., Donnelly, A.J., West, B., and 

nickel subsulfide. Cancer Res. 36, 1790-1800. 

manganese on carcinogenicity and metabolism of 

Onkelinx, C., imd Goldblatt, P.J. (1976). Effects of 

Minghetti, P.P., Maenza, R.M., Becker, N., 

Sunderman, F.W., Jr., Kasprzak, K.S., Lau, T.J., 

Toxicol. Appl. Pharmacol. 43, 381-390. 

Embryotoxicity and fetal toxicity of nickel in rats. 

Allpass, P.R., and Damjanov, I. (1978). 

Sunderman, F.W., Jr., Shen, S.K., Mitchell, J.M., 

Ms.), pp. 399-416. Plenum Press, New York. 

(T.W. Clarkson, G.F. Nordberg, and P.R. Sager, 

and Developmental Toxicity of Metals 

teratogenicity of nickel compounds. In Reproductive 

Kevorkian, C.B. (1 983). Embryotoxicity and 

Sunderman, F.W., Jr., Reid, M.C., Shen, S.K., and 

Carcinogenesis 5, 1511-1517. 

intrarenal injection of nickel compounds. 

erythrocytosis and renal cancers in rats following 

Hopfer, S.M. (1984). Association between 

Sunderman, F.W., Jr., McCully, K.S., and 

Carcinogenesis 8, 305-3 13. 

and biological effects of nickel oxides. 

Costa, M. (1987). Physicochemical characteristics 

Conway, K., Miller, C., Patierno, S.R., and 

McCully, .K.S., Cecutti, A.G., Thornhill, P.G., 

Sunderman, F.W., Jr., Hopfer, S.M., Knight, J.A., 

inhalation. Biol. Trace Elem. Res. 8, 203-210. 

deposited nickel oxide aerosol in rat lung by 

and Tsuchiya, K. (1985). Biological half time of 

Tanaka, I., Ishimatsu, S., Matsuno, K., Kodama, Y., 

Res. 16, 19-26. 

rats after continuous inhalation. Biol. Trace Elem. 

nickel oxide aerosol and histopathological findings in 

and Tsuchiya, K. ' (1988). Lung burden of green 

Tanaka, I., Horie, A., Haratake, J., Kodama, Y., 

analysis. Biometrika 62, 679-682. 

Tarone, R.E. (1975). Tests for trend in life table 
118 Nickel Sulfate Hexahydrate, NTP TR 454 

genetic toxicity assays. Science 236, 933-941. 

chemical carcinogenicity in rodents from in vitro 

Anderson, B., and Minor, R. (1987). Prediction of 

Caspary, W., Resnick, M., Stasiewicz, S., 

Zeiger, E., Haseman, J.K., Spalding, J., 

Tennant, R.W., Margolin, B.H., Shelby, M.D., 

Res. 53, 4172-4174. 

mutation for oxygen free radical damage. Cancer 

Loeb, L.A. (1993). Nickel induces a signature 

Tkeshelashvili, L.K., Reid T.M., McBride, T. J., and 

Sci. 9, 289-298. 

active and retired nickel workers. Ann. Clin. Lab. 

concentrations in nasal mucosa, plasma, and urine in 

Torjussen, W., and Andersen, I. (1979). Nickel 

Washington, DC. 

Department of the Interior, Bureau of Mines, 

Bureau of Mines Minerals Yearbook 1984. U.S. 

United States Bureau of Mines (1 984). Nickel. In 

Washington, DC. 

Department of the Interior, Bureau of Mines, 

Mineral Facts and Problems, I985 Edition. US. 

United States Bureau of Mines (1985a). Nickel. In 

strain A/J mice. Environ. Res. 34, 328-334. 

clearance of intratracheally administered 63Ni,Sz in 

Valentine, R., and Fisher, G.L. (1984). Pulmonary 

nickel workers. Carcinogenesis 5, 1525- 1527. 

aberrations in peripheral lymphocytes of retired 

(1984). Increased incidence of chromosomal 

Waksvik, H., Boysen, M., and Hergetveit, A.C. 

University Press, Oxford. 

Scientific Publications No. 53, pp. 419-438. Oxford 

C. Rosenfeld, R. Saracci, and A. Son, Eds.j, IARC 

P.C. Jacquignon, E. Mastromatteo, J.P. Rigaut, 

C. Bishop, E. Buringh, W. Davis, M. Gounar, 

(F.W. Sunderman, Jr., A. Aitio, A. Berlin, 

products. In Nickel in the Human Environment 

airborne nickel in producing and using primary nickel 

Warner, J.S. (1984). Occupational exposure to 

Hyg. ASSOC. J. 36, 801-810. 

oxide and cigarette smoke by hamsters. Am. Znd. 

Craig, D.K. (1975). Chronic inhalation of nickel 

Wehner, A.P., Busch, R.H., Olson, R.J., and 

hamsters. Prog. Exp. Tumor Res. 24, 177-198. 

(1979). Inhalation studies with Syrian golden 

Wehner, A.P., Stuart, B.O., and Sanders, C.L. 

United states Bureau Of Mines (1985b)‘ In Kordel, W. (1980). Subchronic effects induced by Weischer, C.H., Oldiges, H., Hochrainer, D., and 

R. Lauwerys, M. Mercier, and M. Roberfroid, 

Toxicity and Hazard Evaluation (B. Holmstedt, 

NiO-inhalation in Wistar rats. In Mechanisms of 

Washington, DC. 

Department of the Interior, Bureau of Mines, 

Mineral Commodity Summaries 1985. 

Washington, DC. 

Department of the Interior, Bureau of Mines, 

Mineral Commodity Summaries 1991. U.S. 

United States Bureau of Mines (1991). Nickel. In 

Environmental Assessment, Washington, DC. 

83/012FF), pp. 1-83. Office of Health and 

Nickel andNickel Compounds (EPA/600/8- 

(USEPA) (1986). Health Assessment Document for 

United States Environmental Protection Agency 

Biomedical Press, New York. 

Eds.), pp. 555-558. ElseviedNorth-Holland 

27, 103-1 17. 

are compared with a zero dose control. Biometrics 

between treatment means when several dose levels 

Williams, D.A. (1971). A test for differences 

28, 5 19-53 1. 

dose levels with a zero dose control. Biometrics 

Williams, D. A. (1972). The comparison of several 
References 119 

Health Organization, Geneva. 

Environmental Health Criteria 108: Nickel. World 

World Health Organization (WHO) (1 991). 

9-22. 

rhabdomyosarcomata in rats. Acta Pathol. Jpn. 30, 

Abandowitz, H . M . ( 1980). Nickel sulphide-induced 

Yamashiro, S., Gilman, J.P.W., Hulland, T.J., and 

tract mucosa. Cancer Res. 38, 3140-3145. 

Carcinogenicity of nickel subsulfide for respiratory 

Yarita, T., and Nettesheim, P. (1978). 

Mol. Mutagen. 16 (Suppl. 18), 1-14. 

earlier results with 41 additional chemicals. Envirun. 

predicting rodent carcinogenicity: Confirmation of 

Evaluation of four in vitro genetic toxicity tests for 

Margolin, B.H., and Tennant, R.W. (1990). 

Zeiger, E., Haseman, J.K., Shelby, M.D., 

(Suppl. 21), 2-141. 

311 chemicals. Envirun. Mol. Mutagen. 19 

mutagenicity tests: V. Results from the testing of 

and Mortelmans, K. (1992). Salmonella 

Zeiger, E., Anderson, B., Haworth, S., Lawlor, T., 
120 Nickel Sulfate Hexahydrate, NTP TR 454 
121 

OF NICKEL SULFATE HEXAHYDRATE 

SUMMARY OF LESIONS IN MALE RATS 

APPENDIX A 

IN THE 2-YEAR INHALATION STUDY 

TABLE A4 Historical Incidence of Lung Neoplasms in Untreated Male F344/N Rats 

TABLE A3 Statistical Analysis of Primary Neoplasms in Male Rats 

TABLE A2 Individual Animal Tumor Pathology of Male Rats 

TABLE A1 Summary of the Incidence of Neoplasms in Male Rats 

TABLE A5 Summary of the Incidence of Nonneoplastic Lesions in Male Rats 

in the 2-Year Inhalation Study of Nickel Sulfate Hexahydrate 

in the 2-Year Inhalation Study of Nickel Sulfate Hexahydrate 

in the 2-Year Inhalation Study of Nickel Sulfate Hexahydrate ................ 

150 

128 

122 

157 

156 

................ 

................ ......... 

in the 2-Year Inhalation Study of Nickel Sulfate Hexahydrate ................ 
122 Nickel Sulfate Hexahydrate, NTP TR 454 

Summary of the Incidence of Neoplasms in Male Rats in the 2-Year Inhalation Study of Nickel Sulfate Hexahydratea 

TABLE A1 

Early deaths 

15-Month interim evaluation 

7-Month interim evaluation 

Animals initially in study 

Disposition Summary 

Natural deaths 

Moribund 

Accidental death 

Terminal sacrifice 

Died last week of study 

Survivors 

5 

5 

64 

4 

34 

16 

5 

5 

63 

7 

30 

16 

5 

5 

63 

3 

31 

1 

18 

5 

5 

63 

4 

28 

20 

1 

Animals examined microscopically 64 63 63 63 

7-Month Interim Evaluation 

Brain 

Nervous System 

Oligodendroglioma NOS 

Urinary System 

Special Senses System 

Respiratory System 

Musculoskeletal System 

Integumentary System 

Hematopoietic System 

Genital System 

General Body System 

Endocrine System 

Cardiovascular System 

Alimentary System 

Systems Examined With No Neoplasms Observed 

Islets, pancreatic 

Endocrine System 

15-Month Interim Evaluation 

Pars distalis, adenoma 

Pituitaly gland 

Adenoma 

(5) 

(5) 

(5) 

(5) 

(5) 

(5) 

1 (20%) 

2 (40%) 

(5) 

1 (20%) 

Testes 

Genital System 

(5) (5) (5) (5) 

Bilateral, interstitia1 cell, adenoma 5 (100%) 5 (100%) 5 (100%) 4 (80%) 
Lesions in Male Rats 123 

(continued) 

Summary of the Incidence of Neoplasms in Male Rats in the 2-Year Inhalation Study of Nickel Sulfate Hexahydrate 

TABLE A1 

Spleen 

Lymph node, bronchial 

Hematopoietic System 

15-Month Interim Evaluation (continued) 

(5) 

(5) 

Skin 

Integumentary System 

Keratoacanthoma 

Multiple organsb 

Systemic Lesions 

(5) (5) (5) (5) 

Leukemia mononuclear 1 (20%) 

Urinary System 

Special Senses System 

Respiratory System 

Nervous System 

Musculoskeletal System 

General Body System 

Cardiovascular System 

Alimentary System 

Systems Examined With No Neoplasms Observed 

2- Year Study 

Intestine large, cecum 

Intestine large, colon 

Alimentary System 

Liver 

Intestine small, ileum 

Intestine small, jejunum 

Intestine small, duodenum 

Sarcoma 

Hepatocellular adenoma 

Hepatocellular carcinoma 

Cholangiocarcinoma 

Schwannoma benign 

Lipoma 

Mesentery 

Tongue 

Stomach, glandular 

Stomach, forestomach 

Salivaly glands 

Pancreas 

Squamous cell papilloma 

Squamous cell carcinoma 

Oral mucosa 

Squamous cell carcinoma 

(54) 

(54) ' 

2 (4%) 

(4) 

2 (50%) 

2 (4%) 

(1) 
124 Nickel Sulfate Hexahydrate, NTP TR 454 

Heart 

Cardiovascular System 

2-YeW study (continued) 

Endocrine System 

Osteosarcoma, metastatic, bone 

Adenoma 

Adrenal cortex 

Bilateral, pheochromocytoma benign 

Pheochromocytoma benign 

Pheochromocytoma malignant 

Osteosarcoma, metastatic, bone 

Carcinoma 

Adenoma 

Islets, pancreatic 

Pituitary gland 

Adenoma 

Parathyroid gland 

Pars distalis, adenoma 

Follicular cell, carcinoma 

Follicular cell, adenoma 

Ccell, carcinoma 

Ccell, adenoma 

Bilateral, C-cell, adenoma 

Thyroid.gland 

Adrenal medulla 

1 (2%) 

1 (2%) 

(54) 

2 (4%) 

5 (9%) 

11 (20%) 

(52) 

(49) 

(53) 

(54) 

'7 (13%) 

1 (2%) 

13 (24%) 

(53) 

1 (2%) 

(53) 

6 (11%) 

10 (19%) 

3 (6%) 

1 (2%) 

(51) 

(51) 

1 (2%) 

1 (2%) 

(53) 

12 (23%) 

2 (4%) 

1 (2%) 

2 (4%) 

2 (4%) 

1 (2%) 

1 (2%) 

General Body System 

Thoracic, chordoma 

Abdominal, chondrosarcoma 

Paraganglioma 

Fibroma 

Cholangiocarcinoma, metastatic, liver 

Tissue NOS (4) (1) 

1 (25%) 

1 (2?%) 

1 (25%) 

1 (25%) 

1 (25%) 

Preputial gland 

Epididymis 

Genital System 

Adenoma 

Testes 

Seminal vesicle 

Prostate 

Carcinoma 

Interstitial cell, adenoma 

Bilateral, interstitial cell, adenoma 

(54) 

(54) 

1 (2%) 

2 (4%) 

(54) 

(54) 

(54) 

13 (24%) 

32 (59%) 

3 (6%) 

(53) 

(53) 

(53) 

8 (15%) 

38 (72%) 

(52) 

(53) 

1 (2%) 

3 (6%) 

(53) 

(53) 

(53) 

7 (13%) 

38 (72%) 

(53) 

(53) 

1 (2%) 

3 (6%) 

(53) 

(53) 

(53) 

11 (21%) 

39 (74%) 
Lesions in Male Rats 125 

(continued) 

Summary of the Incidence of Neoplasms in Male Rats in the 2-Year Inhalation Study of Nickel Sulfate Hexahydrate 

TABLE A1 

O mg/m3 0.12 mg/m3 0.25 mg/m& 0.5 mg/m3 

Bone marrow 

Hematopoietic System 

2-YeW study (continued) 

Osteosarcoma, metastatic, bone 1 (2%) 

Lymph node, mandibular 

Lymph node, bronchial 

Lymph node (11) (14) 

(47) 

(11) 

(52) 

(51) 

(53) 

(49) 

Carcinoma, metastatic, preputial gland 1 (2%) 

(52) 

Squamous cell carcinoma, metastatic, oral 

Hemangioma 

mucosa 

Thymus 

Spleen 

Lymph node, mediastinal 

Lymph node, mesenteric (54) 

(51) 

(49) 

(54) 

Hemangiosarcoma 

Integumentary System 

Fibroadenoma, multiple 

Fibroadenoma 

Adenocarcinoma 

Mammary gland 

Subcutaneous tissue. sarcoma 

Subcutaneous tissue, osteosarcoma 

Lip, trichoepithelioma 

Squamous cell papilloma 

Squamous cell carcinoma 

Lipoma 

Keratoacanthoma 

Fibroma 

Basal cell carcinoma 

Basal cell adenoma 

Skin 

1 (2%) 

(53) 

1 (2%) 

1 (2%) 

1 (2%) 

1 (2%) 

1 (2%) 

4 (8%) 

1 (2%) 1 (2%) 

(53) (53) 

3 (6%) 

1 (2%) 

1 (2%) 

2 (4%) 

1 (2%) 

1 (2%) 

2 (4%) 

1 (2%) 

1 (2%) 

Humerus, osteosarcoma 

Bone 

Musculoskeletal System 

Glioma NOS 

Brain 

Nervous System 
126 Nickel Sulfate Hexahydrate, NTP TR 454 

(continued) 

Summary of the Incidence of Neoplasms in Male Rats in the 2-Year Inhalation Study of Nickel Sulfate Hexahydrate 

TABLE A1 

O mg/m3 0.12 mg/m3 0.25 mg/m$ 0.5 mg/m3 

Lung 

Larynx 

Respiratory System 

&Yeat Study (continued) 

(54) 

(54) 

Pheochromocytoma malignant, metastatic, 

Osteosarcoma, metastatic, bone 

Chordoma, metastatic, tissue NOS 

Alveoladbronchiolar carcinoma 

Alveolar/bronchiolar adenoma 

Squamous cell carcinoma 

1 (2%) 

1 .(2%) 

adrenal medulla 

1 (2%) 

Nose (54) 

1 (2%) 

(53) 

(53) 

1 (2%) 

1 (2%) 

2 (4%) 

Carcinoma 

Zymbal’s gland 

Special Senses System 

(1) 

1 (100%) 

(2) 

2 (100%) 

Kidney 

Urinary System 

(54) (52) (52) 

Renal tubule, adenoma 

Pheochromocytoma malignant, metastatic, 

Osteosarcoma, metastatic, bone 1 (2%) 

adrenal medulla 1 (2%) 

1 (2%) 

Urinary bladder (54) (53) (53) 

1 (2%) 

(53) 

Multiple organs 

Systemic Lesions 

Mesothelioma NOS 

Mesothelioma malignant 

Lymphoma malignant 

Leukemia mononuclear 

(54) (53) (53) (53) 

31 (57%) 

1 (2%) 

1 (2%) 

36 (68%) 

1 (2%) 

38 (72%) 38 (72%) 
Lesions in Male Rats 127 

(continued) 

Summary of the Incidence of Neoplasms in Male Rats in the 2-Year Inhalation Study of Nickel Sulfate Hexahydrate 

TABLE AI 

0 mg/m3 0.12 mg/m3 0.25 mg/m$ 0.5 mg/m3 

Total animals with primary neoplasms' 

Neoplasm Summary 

2-Year study 

15-Month interim evaluation 

7-Month interim evaluation 

2-Year study 

15-Month interim evaluation 

'I-Month interim evaluation 

2-Year study 

15-Month interim evaluation 

53 

5 

Total primary neoplasms 

49 

5 

136 

8 

Total animals with benign neoplasms 

51 

5 

1 

51 

4 

52 

5 

142 

6 

1 

136 

6 

145 

5 

50 

5 

50 

5 

51 

4 

Total benign neoplasms 

15-Month interim evaluation 

2-Year study 

15-Month interim evaluation 

2-Year study 

15-Month interim evaluation 

2-Year study 

2-Year study 

2-Year study 

Total animals with malignant neoplasms 

Total malignant neoplasms 

Total animals with uncertain neoplasms - 

Total metastatic neoplasms 

Total animals with metastatic neoplasms 

benign or malignant 

2-Year study 

7-Month interim evaluation 

2-Year study 

7-Month interim evaluation 

Total uncertain neoplasms 

96 

8 

85 

6 

92 

5 

96 

5 

41 

1 

37 43 41 

50 

1 

6 

2 

39 

3 

3 

50 49 

1 

1 1 

1 

1 1 

a Number of animals examined microscopically at the site and the number of animals with neoplasm 

Primary neoplasms: all neoplasms except metastatic neoplasms 

Number of animals with any tissue examined microscopically 
128 Nickel Sulfate Hexahydrate, NTP TR 454 

0 mg/m’ 

Individual Animal Tumor Pathology of Male Rats in the 2-Year Inhalation Study of Nickel Sulfate Hexahydrate: 

TABLE A2 

~ ~~~~~ 

7226586990597704822647577 

1689013335667911122233555 

1244555555555566666666666 

9360318691370987519487235 

3414610365022460125054324 

0000000000000000000000000 

Number of Days on Study 

Carcass ID Number 

Intestine large, cecum 

Intestine large, rectum 

Intestine large, colon 

Esophagus 

Alimentary System 

......................... 

......................... 

......................... 

......................... 

Liver 

Intestine small, ileum 

Intestine small, jejunum 

Intestine small, duodenum 

Hepatocellular adenoma 

Hepatocellular carcinoma 

Cholangiocarcinoma 

Squamous cell papilloma 

Schwannoma benign 

Pancreas 

Oral mucosa 

Mesentery 

Tooth 

Stomach, glandular 

Stomach, forestomach 

Salivary glands 

......................... 

......................... 

......................... 

......................... 

X 

X 

X 

+ 

+ 

......................... 

......................... 

......................... 

M++++++++++++++++++++++++ 

X 

+ ++ +++ 

Hean 

Cardiovascular System 

......................... 

Adrenal medulla 

Adrenal cortex 

Endocrine System 

Osteosarcoma, metastatic, bone 

Bilateral, pheochromocytoma benign 

Pheochromocytoma benign 

Osteosarcoma, metastatic, bone 

Parathyroid gland 

Adenoma 

Islets, pancreatic 

Thyroid gland 

Pituitary gland 

Pars distalis, adenoma 

......................... X 

......................... .I 

A 

X xx 

M++++++++++++++++++I+++++ 

X 

+M+++++++++++++++++++++++ 

X xx X 

......................... 

MM+++M+++++++++++++++++++ 

xx 

C-cell, adenoma 

-Bilateral, C-cell, adenoma 

X 

Tissue NOS 

General Body System 

Paraganglioma 

Cholangiocarcinoma, metastatic, liver 

A: Autolysis precludes examination 

+ : Tissue examined microscopically 

I: Insufficient tissue 

M: Missing tissue 

Blank: Not examined 

X: Lesion present 
Lesions in Male Rats 129 

0 mg/m3 (continued) 

Individual Animal Tumor Pathology of Male Rats in the 2-Year Inhalation Study of Nickel Sulfate Hexahydrate: 

TABLE A2 

~ ~ _____ ________ ~~_______ ~________ 

8299633380161333336666667’1111 

56118900022233333333333333333 

66666611711171117711171111111 

Number of Days on Study 

Carcass ID Number 

00000000000000000000000000000 Total 

40165656412312455500123601345 Tissues/ 

62250061238595145119443767143 Tumors 

Liver 

Intestine small, ileum 

Intestine small, jejunum 

Intestine small, duodenum 

Intestine large, cecum 

Intestine large, rectum 

Intestine large, colon 

Esophagus 

Alimentary System 

............................. 54 

............................. 54 

............................. 54 

............................. 54 

............................. 54 

............................. 54 

............................. 54 

............................. 54 

Hepatocellular adenoma 

Hepatocellular carcinoma 

Cholangiocarcinoma 

Squamous cell papilloma 

Schwannoma benign 

Pancreas 

Oral mucosa 

Mesentery 

Tooth 

Stomach, glandular 

Stomach, forestomach 

Salivary glands 

X 

+ 

+ + 

X 

+ 9 

............................. 54 

............................. 54 

............................. 54 

............................. 53 

2 

+ + 

Adrenal medulla 

Adrenal cortex 

Endocrine System 

Heart 

Cardiovascular System 

............................. 54 

............................. 54 

1 

............................. 54 

Osteosarcoma, metastatic, bone 

Bilateral, pheochromocytoma benign 

Pheochromocytoma benign 

Osteosarcoma, metastatic, bone 

Parathyroid gland 

Adenoma 

Islets, pancreatic 

Thyroid gland 

Pituitary gland 

C-cell, adenoma 

Bilateral, C-cell, adenoma 

Pars distalis, adenoma 

xx X xx xx X 

X X X xx ............................. 

............................. 

M++++++++++++++++++++++++I+++ 

X x xx X xx 

X 

............................... X 

x xx X X 

53 

13 

54 

49 

2 

52 

5 

11 

1 

7 

1 

Tissue NOS 

General Body System 

X 

+++ + 

1 

1 

4 

Paraganglioma 

Cholangiocarcinoma, metastatic, liver 

X 
130 Nickel Sulfate Hexahydrate, NTP TR 454 

0 mg/m3 (continued) 

Individual Animal Tumor Pathology of Male Rats in the 2-Year Inhalation Study of Nickel Sulfate Hexahydrate: 

TABLE A2 

7226586990597704822647577 

1689013335667911122233555 

1244555555555566666666666 

0000000000000000000000000 

Number of Days on Study 

Carcass ID Number 

9360318691370987519487235 

3414610365022460125054324 

Coagulating gland 

Genital System 

+ 

Preputial gland 

Penis 

Epididymis 

Carcinoma 

Adenoma 

......................... 

.......................... + 

X 

X 

Testes 

Seminal vesicle 

Prostate 

......................... 

......................... 

......................... 

xx xxx 

xx xx xxx 

Interstitial cell, adenoma 

Bilateral, interstitial cell, adenoma X 

X 

Bone marrow 

Hematopoietic System 

Thymus 

Spleen 

Lymph node, mediastinal 

Lymph node, mesenteric 

Lymph node, mandibular 

Lymph node, bronchial 

Lymph node 

Osteosarcoma, metastatic, 

......................... bone X 

+ ++ 

+++++++++++I++++++++++M++ 

......................... 

+++++++++++M+++++++++++++ 

......................... 

++++++++++++++++++++++I++ 

++M++++++++++++++++++++++ 

++ 

Skin 

Mammary gland 

Integumentary System 

++++I++++++++++++++++++++ 

+++++++M+M+++++++++++MM++ 

Keratoacanthoma 

Adenocarcinoma 

Bone 

Musculoskeletal System 

......................... Humerus, osteosarcoma X 

Glioma NOS 

Brain 

Nervous System 

......................... X 

Lung 

Larynx 

Respiratory System 

......................... 

......................... 

Squamous cell carcinoma 

Osteosarcoma, metastatic, bone 

Alveolar/bronchiolar carcinoma 

X 

Trachea 

Nose 

......................... 

......................... 
Lesions in Male Rats 131 

0 mg/m3 (continued) 

Individual Animal Tumor Pathology of Male Rats in the 2-Year Inhalation Study of Nickel Sulfate Hexahydrate: 

TABLE A2 

82996333801613333366666677771 

56778900022233333333333333333 

66666677777177777777777777777 

~~ 

Number of Days on Study 

Carcass ID Number 

00000000000000000000000000000 Total 

40165656412312455500123601345 Tissues/ 

62250061238595145719443767743 Tumors 

Preputial gland 

Penis 

Epididymis 

Coagulating gland 

Genital System 

Adenoma 

Testes 

Seminal vesicle 

Prostate 

Carcinoma 

Interstitial cell, adenoma 

Bilateral, interstitial cell, adenoma 

............................. 

............................. X 

xx xxxxxx xxxxxxxxx xx x xxxx ............................. 

............................. 

............................. 

X X X xx 13 

32 

54 

54 

54 

1 

2 

54 

1 

54 

1 

Bone marrow 

Hematopoietic System 

Thymus 

Spleen 

Lymph node, mediastinal 

Lymph node, mesenteric 

Lymph node, mandibular 

Lymph node, bronchial 

Lymph node 

. Osteosarcoma, metastatic, 

............................. bone 

++++++++M+++++++M+++I++++++++ 

............................. 

++++I++++++++++++++M+++++++++ 

............................. 

............................. 

+++++++++++++++++++M+++M+++++ 

+++ ++ + 

49 

54 

51 

54 

52 

51 

11 

1 

54 

Skin 

Mammary gland 

Integumentary System 

4 

............................. 53 

1 

+MM+M+++++M+M++++++++M++++M++ 43 

Keratoacanthoma 

Adenocarcinoma X 

X xx X 

Humerus, osteosarcoma 

Bone 

Musculoskeletal System 

1 

............................. 54 

Glioma NOS 

Nervous System 

Brain 

1 

............................. 54 

Lung 

Larynx 

Respiratory System 

............................. 54 

............................. 54 

1 

1 

1 

............................. 54 

............................. 54 

Squamous cell carcinoma 

Osteosarcoma, metastatic, bone 

Alveolar/bronchiolar carcinoma X 

X 

Trachea 

Nose 
132 Nickel Sulfate Hexahydrate, NTP TR 454 

0 mg/m3 (continued) 

Individual Animal Tumor Pathology of Male Rats in the 2-Year Inhalation Study of Nickel Sulfate Hexahydrate: 

TABLE A2 

7226586990597704822647577 

1689013335667911122233555 

1244555555555566666666666 

Number of Days on Study 

Carcass ID Number 

9360318691370987519487235 

3414610365022460125054324 

0000000000000000000000000 

Zymbal’s gland 

EY e 

Special Senses System 

Kidney 

Urinary System 

Carcinoma 

......................... Osteosarcoma, metastatic, bone X 

Renal tubule, adenoma 

Uri~ly bladder 

Urethra 

......................... 

+ 

Multiple organs 

Systemic Lesions 

xx ......................... Leukemia mononuclear x x xxxxxxx x 
Lesions in Male Rats 133 

TABLE A2 

0 mg/m3 (continued) 

Individual Animal Tumor Pathology of Male Rats in the 2-Year Inhalation Study of Nickel Sulfate Hexahydrate: 

82996333801613333366666677777 

56778900022233333333333333333 

66666677777777777777777777777 

Number of Days on Study 

Carcass ID Number 

00000000000000000000000000000 Total 

40165656412312455500123601345 Tissues/ 

62250061238595145719443767743 Tumors 

Zymbal’s gland 

EY e 

Special Senses System 

Carcinoma X 

+ 

+ 

Kidney 

Urinary System ............................. 54 

Osteosarcoma, metastatic, bone 1 

Renal tubule, adenoma 

Urinaty bladder 

Urethra 

X 

............................. 54 

1 

1 

Multiple organs 

Systemic Lesions ............................. 54 

Leukemia mononuclear xxx xx x x xxxx xxxxxx xx 31 
134 Nickel Sulfate Hexahydrate, NTP TR 454 

0.12 mg/m3 

Individual Animal Tumor Pathology of Male Rats in the 2-Year Inhalation Study of Nickel Sulfate Hexahydrate: 

TABLE A2 

2397166008075200346085923 

56,34566789001344444557788 

3355555555666666666666666 

Number of Days on Study 

Carcass ID Number 

6435580226049895207601127 

9475401547555548764897508 

1111122111111111111111121 

Intestine large, cecum 

Intestine large, rectum 

Intestine large, colon 

Esophagus 

Alimentary System 

Liver 

Intestine small, ileum 

Intestine small, jejunum 

Intestine small, duodenum 

Oral mucosa 

Lipoma 

Mesentery 

Hepatocellular carcinoma 

Tongue 

Stomach, glandular 

Stomach, forestomach 

Salivary glands 

Pancreas 

Squamous cell papilloma 

Tooth 

Sarcoma 

Squamous cell carcinoma 

......................... 

.......................... 

.......................... 

......................... 

......................... 

++++M+I++++++++++++++++++ 

......................... 

......................... 

X 

+ + 

X 

+ + 

......................... 

......................... 

......................... 

M++++++++++++++++++++++++ 

X 

+ 

+ ~ ~~ ~ 

Heart 

Cardiovascular System 

~~ 

......................... 

Endocrine System 

Adrenal medulla 

Adenoma 

Adrenal cortex 

Bilateral, pheochromocytoma benign 

Pheochromocytoma benign 

Pheochromocytoma malignant 

Parathyroid gland 

Adenoma 

Islets, pancreatic 

Thyroid gland 

Pituitary gland 

......................... X ......................... X X 

X X 

M++++++++++++++++++++++++ 

X 

X 

++++++++++++A++++++++++++ 

++++++++++++++++M++++++++ 

C-cell, carcinoma 

C-cell, adenoma 

Pars distalis, adenoma X X X X X 

......................... 

X 

Tissue NOS 

General Body System 
Lesions in Male Rats 135 

0.12 mgh3 (continued) 

Individual Animal Tumor Pathology of Male Rats in the 2-Year Inhalation Study of Nickel Sulfate Hexahydrate: 

TABLE A2 

3522348006623333666666777777 

Number of Days on Study 8890000222233333333333333333 

6667777717777777777777777177 

Carcass ID Number 

2111111111211112111122111111 Total 

0576678898094690788900445569 Tissues1 

9357444281156944738756186753 Tumors 

Intestine large, cecum 

Intestine large, rectum 

Intestine large, colon 

Esophagus 

Alimentary System 

Liver 

Intestine small, ileum 

Intestine small, jejunum 

Intestine small, duodenum 

Lipoma 

Mesentery 

Hepatocellular carcinoma 

Sarcoma 

............................ 

............................ 

............................ 

............................ 

53 

53 

53 

53 

............................ 53 

............................ 51 

++++++M+++++++++++++++++++++ 52 

............................ 53 

X 1 

X 

X 

++ 

2 

4 

1 

Oral mucosa 

Tongue 

Stomach, glandular 

Stomach, forestomach 

Salivary glands 

Pancreas 

Heart 

Cardiovascular System 

Tooth 3 

1 

1 

............................ 53 

............................ 53 

............................ 53 

............................ 52 

1 

2 

Squamous cell papilloma 

Squamous cell carcinoma 

+ + 

............................ 53 

Endocrine System 

Adrenal medulla 

Adenoma 

Adrenal cortex 

Bilateral, pheochromocytoma benign 

Pheochromocytoma benign 

Pheochromocytoma malignant 

Parathyroid gland 

Adenoma 

Islets, pancreatic 

Thyroid gland 

Pituitary gland 

............................ 

............................ X 

X X X X X 

xx X 

xx 

X X 

++M++++++++++++++++++++++++-tX 

............................ X 

++++++++++++++++M+++++++++++ 

+++++++++M++++++++++++++++++ 

C-cell, adenoma 

Pars distalis, adenoma xx xx x 

X 1 

53 

12 

51 

51 

1 

51 

6 

10 

3 

53 

1 

53 

Tissue NOS 

General Body System 

C-cell, carcinoma 1 

+ 1 
136 Nickel Sulfate Hexahydrate, NTP TR 454 

2397166008075200346085923 

5634566789001344444557788 

3355555555666666666666666 

6435580226049895207601127 

9475401547555548764897508 

1111122111111111111111121 

Number of Days on Study 

Carcass ID Number 

Epididymis 

Coagulating gland 

Genital System 

Mesothelioma malignant, metastatic, 

Preputial gland 

testes 

Testes 

Seminal vesicle 

Prostate 

Carcinoma 

Interstitial cell, adenoma 

Bilateral, interstitial cell, adenoma 

++ + ......................... 

n 

......................... X X X 

......................... 

......................... 

......................... 

X xxxxxxx xx xxxxxx 

X xx X 

Lymph node, bronchial 

Lymph node 

Bone marrow 

Hematopoietic System 

Carcinoma, metastatic, 

Spleen 

Lymph node, mediastinal 

Lymph node, mesenteric 

Lymph node, mandibular 

preputial gland 

Thymus 

Hemangiosarcoma 

++++++++++++++++++I +I ++++ 

++++++++++++A++++++++++++ 

+ + + + + 

x 

......................... 

......................... 

......................... 

......................... 

+++++M++++++Af++++++++++M 

Mammary gland 

Integumentary System 

++++++M++++++++++++++++++ 

Fibroadenoma, multiple 

Adenocarcinoma 

Lip, trichoepithelioma 

Squamous cell carcinoma 

Lipoma 

Keratoacanthoma 

Fibroma 

X 

Skin ......................... 

Brain 

Nervous System 

Bone 

Musculoskeletal System 

Trachea 

Nose 

Lung 

Larynx 

Respiratory System 

......................... 

......................... 

......................... 

A++++++++++++++++++++++++ 

......................... 

A++++++++++++++++++++++++ 
Lesions in Male Rats 137 

0.12 mg/m3 (continued) 

Individual Animal Tumor Pathology of Male Rats in the 2-Year Inhalation Study of Nickel Sulfate Hexahydrate: 

TABLE A2 

352234800662333366666677717’1 

8890000222233333333333333333 

6667777777177777777777777777 

Number of Days on Study 

Carcass ID Number 

2111111111211112111122111111 Total 

0576678898094690788900445569 Tissues1 

9351444281156944738756186153 Tumors 

Epididymis 

Coagulating gland 

Genital System 

Mesothelioma malignant, metastatic, 

Preputial gland 

testes 

Testes 

Seminal vesicle 

Prostate 

Carcinoma 

Interstitial cell, adenoma 

Bilateral, interstitial cell, adenoma 

53 

3 

............................ 

8 

38 

53 

53 

53 

3 

53 

1 

............................ 

x xx xxxxxxxx xxxxxxxxxx x ............................ 

............................ 

............................ 

xx X X 

Lymph node, bronchial 

Lymph node 

Bone marrow 

Hematopoietic System 

++++M++++++++++++++++I++++++ 

++ ++++ ............................ 

49 

14 

52 

++ + 

Carcinoma, metastatic, 

Spleen 

Lymph node, mediastinal 

Lymph node, mesenteric 

Lymph node, mandibular 

preputial gland 

Thymus 

Hemangiosarcoma 

53 

49 

53 

53 

1 

48 

1 

............................ 

++M+++++++++++++M++M+++++++I 

............................ 

............................ 

........................... X 

Mammary gland 

Integumentary System 

Fibroadenoma, multiple 

Adenocarcinoma 

Lip, trichoepithelioma 

Squamous cell carcinoma 

Lipoma 

Keratoacanthoma 

Fibroma 

Skin 

~ ~~~ 

M+++++++++M++++.++++M+++++++M 

1 

1 

48 

1 

1 

1 

1 

1 

53 

X 

............................ 

X 

X 

X 

X 

X 

Bone 

Musculoskeletal System 

............................ 53 

Brain 

Nervous System 

Trachea 

Nose 

Lung 

Larynx 

Respiratory System 

~~ 

............................ 53 

............................ 

............................ 

............................ 

............................ 

53 

52 

53 

52 
138 Nickel Sulfate Hexahydrate, NTP TR 454 

TABLE A2 

0.12 mg/m3 (continued) 

Individual Animal Tumor Pathology of Male Rats in the 2-Year Inhalation Study of Nickel Sulfate Hexahydrate: 

2397166008075200346085923 

Number of Days on Study 5634566789001344444557788 

3355555555666666666666666 

Carcass ID Number 

6435580226049895207601127 

9475401547555548764897508 

1111122111111111111111121 

None 

Special Senses System 

Kidney 

Urinary System 

++++++++++++A++++++++++++ 

metastatic, adrenal medulla 

Pheochromocytoma malignant, 

X 

Multiple organs 

Systemic Lesions 

Urinary bladder 

Urethra 

......................... 

++ 

X 

x xxxxx x x xx x x xx ......................... 

Mesothelioma NOS 

Mesothelioma malignant 

Leukemia mononuclear 

X 

\ 
Lesions in Male Rats 139 

0.12 mg/m3 (continued) 

Individual Animal Tumor Pathology of Male Rats in the %Year Inhalation Study of Nickel Sulfate Hexahydrate: 

TABLE 

3522348006623333666666777777 

Number of Days on Study 8890000222233333333333333333 

6667777777777777777777777777 

Carcass ID Number 

2111111111211112111122111111 Total 

0576678898094690788900445569 Tissues/ 

9357444281156944738756186753 Tumors 

None 

Special Senses System 

~~ ~ ~~ ~ ~~~~~~~ ~~ ~~~ ~~ ~ 

Kidney 

Urinary System 

~~ ~~~~ 

............................ 52 

53 

3 

metastatic, adrenal medulla 1 

Pheochromocytoma malignant, 

Urinary bladder 

Urethra + ............................ 

Multiple organs 

Systemic Lesions 

1 

1 

xxx xxxxx xxxx xxxx x x xxxx 36 

............................ 53 

Mesothelioma NOS 

Mesothelioma malignant 

Leukemia mononuclear 
140 Nickel Sulfate Hexahydrate, NTP TR 454 

TABLE A2 

9212558011677167471831934 

Number of Days on Study 7379333555799000112245788 

2444555555555666666666666 

3233233322322332232323333 

Carcass ID Number 

2012768744561679315984468 

0924901389189308849394224 

Esophagus 

Alimentary System ~~ ~~~~ ~ 

......................... 

Intestine small, ileum 

Intestine small, jejunum 

Intestine small, duodenum 

Intestine large, cecum 

Intestine large, rectum 

Intestine large, colon 

++AA+++M+++++++++++++++++ 

++AA+++++++++++++++++++++ 

++AA+++++++++++++++++++++ 

......................... 

++++++++++I++++++++++++++ 

......................... 

Liver ......................... 

Squamous cell papilloma 

Squamous cell carcinoma 

Hepatocellular adenoma 

Oral mucosa 

Pancreas 

X 

+ 

X 

......................... Salivary glands ......................... 

Tooth 

Stomach, glandular 

Stomach, forestomach 

......................... 

......................... 

+++ 

Heart 

Cardiovascular System 

Adrenal medulla 

Adrenal cortex 

Endocrine System 

......................... 

.......................... 

......................... 

Pheochromocytoma benign 

Pheochromocytoma malignant 

Carcinoma 

Adenoma 

Islets, pancreatic 

Thyroid gland 

Pituitary gland 

Parathyroid gland 

Follicular cell, adenoma 

C-cell, adenoma 

Pars distalis, adenoma 

A 

X X X 

......................... 

X 

......................... 

+++M+++++++++++++++++++++ 

xx X xx xx 

+++A+++++++++++++++++++++ 

X 

Fibroma 

Tissue NOS 

General Body System 

+ + + + 
Lesions in Male Rats 141 

0.25 mg/m3 (continued) 

Individual Animal Tumor Pathology of Male Rats in the 2-Year Inhalation Study of Nickel Sulfate Hexahydrate: 

TABLE A2 

5761375672333333366661171111 

8901112223333333333333333333 

6617117711711711111117111111 

Number of Days on Study 

Carcass ID Number 

3323333333223333333333333333 Total 

5180213400880011423340012244 Tissues1 

0918231939120406603451525831 Tumors 

Liver 

Intestine small, ileum 

Intestine small, jejunum 

Intestine small, duodenum 

Intestine large, cecum 

Intestine large, rectum 

Intestine large, colon 

Esophagus 

Alimentary System 

Oral mucosa 

Squamous cell papilloma 

Squamous cell carcinoma 

Hepatocellular adenoma 

Tooth 

Stomach, glandular 

Stomach, forestomach 

Salivary glands 

Pancreas 

............................ 

+++++AA+++++++++++++++++++++ 

++++++A+++++++++++++++++++++ 

............................ 

............................ 

............................ 

............................ 

............................ 

X 

X 

+ 

X 

+ 

X 

+ 

............................ 

++++++++++++++++++++++++M+++ 

............................ 

............................ 

53 

48 

50 

51 

53 

52 

53 

53 

1 

3 

4 

2 

53 

52 

53 

53 

3 

Heart 

Cardiovascular System ............................ 53 

Adrenal medulla 

Adrenal cortex 

Endocrine System 

............................ 

............................ 

52 

12 

2 

53 

53 

1 

2 

51 

18 

53 

51 

1 

1 

Pheochromocytoma benign 

Pheochromocytoma malignant 

Carcinoma 

Adenoma 

Islets, pancreatic 

Thyroid gland 

Pituitary gland 

Parathyroid gland 

X 

X X X X X 

+++++++++++++M++++++++++++++ 

xxxx 

X 

+++++A++++++++++++++++++++++ 

xx 

............................ 

++++M+++++++++++++++++++++++ 

Follicular cell, adenoma 

C-cell, adenoma 

Pars distalis, adenoma X xxxx xx x X 

X 

X 

Fibroma 

Tissue NOS 

General Body System 

X 

+ 

1 

5 
0.25 mg/m3 (continued) 

Individual Animal Tumor Pathology of Male Rats in the 2-Year Inhalation Study of Nickel Sulfate Hexahydrate: 

TABLE A2 

9212558011677167471831934 

7379333555799000112245788 

2444555555555666666666666 

Number of Days on Study 

Carcass ID Number 

2012768744561679315984468 

0924901389189308849394224 

3233233322322332232323333 

Preputial gland 

Epididymis 

Genital System 

Carcinoma 

Adenoma 

Prostate 

......................... 

.......................... 

xx 

X ......................... 

Testes 

Seminal vesicle 

xxxx xxxx xx x xxx ......................... 

......................... 

Interstitial cell, adenoma 

Bilateral, interstitial cell, adenoma 

xx xx 

Lymph node, mandibular 

Lymph node, bronchial 

Lymph node 

Bone marrow 

Hematopoietic System 

......................... 

+M+A+++++++++++++++++++++ 

+++ ......................... ++ + 

Squamous cell carcinoma, metastatic, 

oral mucosa 

Lymph node, mesenteric ......................... Hemangioma 

Thymus 

Spleen 

Lymph node, mediastinal 

++AA+++++M+++++++++++++++ 

++AA+++++++++++++++++++++ 

M+A++++M+++++++++++++++++ 

~ ~~ ~ ~~ 

Skin 

Mammary gland 

Integumentary System 

~~~ 

++M++++++++++++M+++++++++ 

Fibroadenoma 

Subcutaneous tissue, sarcoma 

Squamous cell papilloma 

Lipoma 

Keratoacanthoma 

......................... 

Bone 

Musculoskeletal System 

......................... 

Brain 

Nervous System 

......................... ~~ ~~ 

Lung 

Larynx 

Respiratory System 

......................... 

......................... 

metastatic, adrenal medulla 

Pheochromocytoma malignant, 

Alveolar/bronchiolar carcinoma 

X 

Trachea 

Nose ......................... 

......................... 
I 

ES 

ES 

ES 

ES 

I 

............................ 

............................ asoN 

eaq3wL 

e[[npaur [euaJpe ‘a!iqsqam 

eUlOU!3Je3 JB[O!q3UOJq/Je[OaAlV 

‘lUEU%![ElU EUIOlr(3OWOJq3Oa~d 

X 

............................ 

............................ 

map& LJO~J!~S

xuhe? 

%un? 

ES ............................ 

ES ............................ maw& 1qapysopwmm 

auoa 

6P ......................... +++ 

I 

ES 

I 

I 

2 

I X 

euroqnxe3eolwa~ 

emod!? 

auroll!ded llas snourenbs 

euro3les ‘anssp snoawn3qng 

eruouapeoJq!d 

xx 

X 

............................ X 

ma3sLs 6Je3uaurnsaluI 

puq% hmeyy 

U!YS 

X 

Z 

ES 

I 

9P 

IS 

8P 

ZS +++++++++++++++++++++v++++++ 

I1 

LP ++ I+++++N++++++N+++++++++++I 

IS +++++++++++I++++++++++++++++ 

+++N++++++++++N++++++++++IxM+ 

............................ 

+++++++++N++H+++++++++++++++ 

[eupse!paru ‘apou qdurr(7 

uaaIdS 

snrur(u 

aualuasaru ‘apou ydurr(? 

X 

eso3nw jwo 

mo!%umag 

............................ X X 

‘a!msqaru ‘moupea lIa3 snoruenbs 

ura~sLg qa!odowuraH 

MOIIEW auoa 

apou qdurr(7 

lerq3uoIq ‘apou qdurr(7 

qnq!pueur ‘apou qdurd? 

+ + ++ + 

ES ............................ ZS ++I+++++++++++++++++++++++++ 

E X 

I 

ES ............................ ES ............................ ES ............................ 8E xxxxxxx xxxxx xxxxx.xxxxX xx euxouape ‘\la3 IeppsJaiu! ‘lua1e1!8 

L X xx eurouape ‘1Ia3 

alvsoId 

ap!saA pxquras 

sa1saL 

PI@ @pndaJd 

mouapv 

EUIOU!3JE3 

urapLg pqua3 

S!urr(P!P!dEl 

SIOurIu LE8SZSISPE0990POtI6E6IEZ8L60 

/sanss!L PPZZlOOPEEZPI1008800PEIZO8IS 

POL EEEEEEEEEEEEEEEEZZEEEEEEEZEE 

LLLLLLLLLLLLLLLLLLLLLLLLLL99 

EEEEEEEEEEEEEEEEEEEZZZIllO68 

LLLLLLL9999EEEEEEEZL9SLEl9LS 

JJqUlnN <H SSeJJE3 

dpn~g uo ska JO raqmnN 
144 Nickel Sulfate Hexahydrate, NTP TR 454 

TABLE A2 

0.25 mg/m3 (continued) 

Individual Animal Tumor Pathology of Male Rats in the 2-Year Inhalation Study of Nickel Sulfate Hexahydrate: 

9212558011677167471831934 

7379333555799000112245788 

2444555555555666666666666 

2012768744561679315984468 

0924901389189308849394224 

3233233322322332232323333 

Number of Days on Study 

Carcass ID Number 

Zymbal’s gland 

EY e 

Ear 

Special Senses System 

Carcinoma 

+ 

X 

+ 

X 

+ 

Urinaly bladder 

Kidney 

Urinary System 

......................... 

+++A+++++++++++++++++++++ 

Multiple organs 

Systemic Lesions 

xxxxxxxxx xx xx ......................... 

Lymphoma malignant 

Leukemia mononuclear 

X 
Lesions in Male Rats 145 

0.25 mg/m3 (continued) 

Individual Animal Tumor Pathology of Male Rats in the 2-Year Inhalation Study of Nickel Sulfate Hexahydrate: 

TABLE A2 

5761375672333333366667777777 

8901112223333333333333333333 

6677777777777777777777777777 

3323333333223333333333333333 Total 

5180213400880011423340012244 Tissues/ 

0978231939120406603451525837 Tumors 

Number of Days on Study 

Carcass ID Number 

Zymbal’s gland 

EY e 

Ear 

Special Senses System 

Carcinoma 

Urinary bladder 

Kidney 

Urinary System 

Multiple organs 

Systemic Lesions 

2 

2 

1 

1 

+ 

............................ 

............................ 53 

52 

1 

xxxxxx xxxxxx xxx xxxxx xxx 38 

............................ 53 

Lymphoma malignant 

Leukemia mononuclear 
146 Nickel Sulfate Hexahydrate, NTP TR 454 

0.5 mg/m3 

Individual Animal Tumor Pathology of Male Rats in the 2-Year Inhalation Study of Nickel Sulfate Hexahydrate: 

TABLE A2 

0903092363442888904801416 

Number of Days on Study 2123635678880222233345577 

3444455555556666666666666 

4444444444444444444444444 

Carcass ID Number 

8632152712795435760821649 

6644787386472377754325226 

Liver 

Intestine small, ileum 

Intestine small, jejunum 

Intestine small, duodenum 

Intestine large, cecum 

Intestine large, rectum 

Intestine large, colon 

Esophagus 

Alimentary System 

Tooth 

Stomach, glandular 

Stomach, forestomach 

Salivary glands 

Pancreas 

Mesentery 

Hepatocellular adenoma 

......................... 

......................... 

......................... 

......................... 

++++++++++++++++++++++++M 

+++++++++++++++++I++++++M 

++++++++++++++++++++++++A 

......................... 

X X 

+ 

......................... 

+++++++++++++++M+++++++++ 

......................... 

......................... 

+ 

Heart 

Cardiovascular System 

......................... 

Adrenal medulla 

Adrenal cortex 

Endocrine System 

Bilateral, pheochromocytoma benign 

Pheochromocytoma benign 

Pheochromocytoma malignant 

Carcinoma 

Adenoma 

Islets, pancreatic 

Pars distalis, adenoma 

Pituitary gland 

Adenoma 

Parathyroid gland 

Follicular cell, carcinoma 

C-cell, carcinoma 

C-cell, adenoma 

Thyroid gland 

......................... 

......................... 

......................... X X 

X 

++A++M++++++++++++IM+++++ 

......................... X X X 

++A++++++++++++++++++++++ 

X 

Tissue NOS 

General Body System 

Thoracic, chordoma 

Abdominal, chondrosarcoma 

Paraganglioma 

+ 

X 

+ 

Preputial gland 

Epididymis 

Genital System 

Carcinoma 

Adenoma 

Seminal vesicle 

Prostate 

.......................... 

......................... 

X X 

X 

......................... 

......................... 
Lesions in Male Rats 147 

0.5 mg/m3 (continued) 

Individual Animal Tumor Pathology of Male Rats in the 2-Year Inhalation Study of Nickel Sulfate Hexahydrate: 

TABLE A2 

8877936333333333666667777777 

8899912333333333333333333333 

6666677777777777777777777777 

Number of Days on Study 

Carcass ID Number 

4444444444444444444444444444 Total 

3728248224667789234454555668 Tissues1 

5833982789030440114695057170 Tumors 

Liver 

Intestine small, ileum 

Intestine small, jejunum 

Intestine small, duodenum 

Intestine large, cecum 

Intestine large, rectum 

Intestine large, colon 

Esophagus 

Alimentary System 

Tooth 

Stomach, glandular 

Stomach, forestomach 

Salivary glands 

Pancreas 

Mesentely 

Hepatocellular adenoma 

............................ 

............................ 

............................ 

............................ 

............................ 

+++++++++++++++I++++++++++++ 

............................ 

............................ 

............................ 

............................ 

............................ 

............................ 

+ + 

53 

53 

53 

53 

52 

50 

52 

53 

3 

53 

52 

53 

53 

1 

2 

Heart 

Cardiovascular System ............................ 53 

Adrenal medulla 

Adrenal cortex 

Endocrine System 

Bilateral, pheochromocytoma benign 

Pheochromocytoma benign 

Pheochromocytoma malignant 

Carcinoma 

Adenoma 

Islets, pancreatic 

Pars distalis, adenoma 

Pituitary gland 

Adenoma 

Parathyroid gland 

Follicular cell, carcinoma 

C-cell, carcinoma 

C-cell, adenoma 

Thyroid gland 

............................ 

X 

............................ 

X .x x x X X X X X 

X X 

X 

............................ X 

............................ X 

............................ x xxxx X xx X X 

............................ A 

X 

X 1 

2 

1 

52 

13 

53 

1 

48 

1 

4 

53 

2 

9 

1 

53 

53 

Tissue NOS 

General Body System 

Thoracic, chordoma 

Abdominal, chondrosarcoma 

Paraganglioma 

+ + 

1 

1 

1 

4 

X 

X 

Preputial gland 

Epididymis 

Genital System 

Carcinoma 

Adenoma 

............................ 

............................ 

53 

53 

1 

3 

53 

53 

X 

Seminal vesicle 

Prostate 

............................ 

............................ 
148 Nickel Sulfate Hexahydrate, NTP TR 454 

TABLE A2 

0.5 mg/m3 (continued) 

Individual Animal Tumor Pathology of Male Rats in the 2-Year Inhalation Study of Nickel Sulfate Hexahydrate: 

0903092363442888904801416 

Number of Days on Study 2123635678880222233345577 

3444455555556666666666666 

Carcass ID Number 

8632152712795435760821649 

6644787386472377754325226 

4444444444444444444444444 

Testes 

Genital System (continued) 

Interstitial cell, adenoma 

Bilateral, interstitial cell, adenoma xx xx X xxx xxxxxxxx ......................... 

xxx x xx X 

Lymph node, bronchial 

Lymph node 

Bone marrow 

Hematopoietic System 

......................... ++ + ++ ......................... +++ 

Thymus 

Spleen 

Lymph node, mediastinal 

Lymph node, mesenteric 

Lymph node, mandibular 

+++++++IM++++M+M++++M++++ 

......................... 

+M+++++++++++++++++++++++ 

......................... 

......................... 

Skin 

Mammary gland 

Integumentary System 

......................... X 

++.++++MMM+++++++++MM+++++ 

Fibroadenoma 

Subcutaneous tissue, osteosarcoma X 

Squamous cell papilloma 

Fibroma 

Basal cell carcinoma 

Basal cell adenoma X 

X 

Brain 

Nervous System 

Bone 

Musculoskeletal System 

Lung 

Larynx 

Respiratory System 

......................... 

......................... 

......................... 

......................... 

Chordoma, metastatic, tissue NOS 

Alveolar/bronchiolar carcinoma 

Alveolar/bronchiolar adenoma 

X 

Eye 

Special Senses System 

Trachea 

Nose ......................... 

......................... 

~ ~~ 

Multiple organs 

Systemic Lesions 

Urinary bladder 

Urethra 

Kidney 

Urinary System 

......................... Renal tubule, adenoma 

+ ......................... 

xxx xxxxxxxxxxxxxxxx ......................... Leukemia mononuclear 
Lesions in Male Rats 149 

0.5 mg/m3 (continued) 

Individual Animal Tumor Pathology of Male Rats in the 2-Year Inhalation Study of Nickel Sulfate Hexahydrate: 

TABLE A2 

8877936333333333666667777777 

8899912333333333333333333333 

6666677777777777777777777777 

Number of Days on Study 

Carcass ID Number 

4444444444444444444444444444 Total 

3728248224667789234454555668 Tissues1 

5833982789030440114695057170 Tumors 

Testes 

Genital System (continued) 

xx xxxxxxxxxxx xxxxxx xxxx ............................ 

11 

39 

53 

Interstitial cell, adenoma 

Bilateral, interstitial cell, adenoma 

xx X X 

Thymus 

Spleen 

Lymph node, mediastinal 

Lymph node, mesenteric 

Lymph node, mandibular 

Lymph node, bronchial 

Lymph node 

Bone marrow 

Hematopoietic System 

............................ ++ ++ 

++++++++++M++M++++++++++++++ 

............................ 

++++++++++++++++M++++++I++++ 

............................ 

............................ 

+++++++M++++++++++++++++++++ 

46 

53 

50 

53 

53 

52 

12 

53 

Skin 

Mammary gland 

Integumentary System 

Fibroadenoma 

Subcutaneous tissue, osteosarcoma 

Squamous cell papilloma 

Fibroma 

Basal cell carcinoma 

Basal cell adenoma 

++++M+M+++M++++++++++++M++++ 

1 

2 

3 

1 

1 

53 

1 

44 

............................ 

X 

X 

X 

X 

X 

Brain 

Nervous System 

Bone 

Musculoskeletal System 

............................ 53 

............................ 53 

Lung 

Larynx 

Respiratory System - 

............................ 

53 

53 

1 

1 

2 

53 

53 

............................ 

Chordoma, metastatic, tissue NOS 

Alveolar/bronchiolar carcinoma 

Alveolar/bronchiolar adenoma X X 

............................ 

............................ X 

Trachea 

Nose 

EY e 

Special Senses System 

+ 1 

Urinary bladder 

Urethra 

Kidney 

Urinary System 

Renal tubule, adenoma X 

............................ 

53 

1 

1 

53 

............................ 

Multiple organs 

Systemic Lesions 

xx xxxxxxxx xxxxx 

............................ 38 

53 

Leukemia mononuclear x xxx 
150 Nickel Sulfate Hexahydrate, NTP TR 454 

Statistical Analysis of Primary Neoplasms in Male Rats in the 2-Year Inhalation Study of Nickel Sulfate Hexahydrate 

TABLE A3 

O mg/m3 0.12 mg/m3 0.25 mg/m3 0.5 mg/m3 

Fisher exact test 

Cochran-Armita e testd 

Logistic regression testd 

Life table testd 

First incidence (days) 

Terminal rate' 

Adjusted rateb 

Overall ratea 

Adrenal Medulla: Benign Pheochromocytoma 

Fisher exact test 

Cochran-Armitage test 

Logistic regression test 

Life table test 

First incidence (days) 

Terminal rate 

Adjusted rate 

Overall rate 

Adrenal Medulla: Malignant Pheochromocytoma 

Fisher exact test 

Cochran-Armitage test 

Logistic regression test 

Life table test 

First incidence (days) 

Terminal rate 

Adjusted rate 

Overall rate 

Adrenal Medulla: Benign or Malignant Pheochromocytoma 

Fisher exact test 

Cochran-Armitage test 

Logistic regression test 

Life table test 

First incidence (days) 

Terminal rate 

Adjusted rate 

Overall rate 

Lung: Alveolarhonchiolar Adenoma or Carcinoma 

P=0.126N 

P=0.085N 

P=0.045N 

622 

7/16 (44%) 

61.2% 

16/54 (30%) 

% 

0116 (0%) 

0.0% 

0/54 (0%) 

e 

P=O.557 

P=O.566 

P=O.601 

- 

P=0.137N 

P=0.092N 

P=0.049N 

622 

7/16 (44%) 

61.2% 

16/54 (30%) 

P=O.O93 

P=O.O98 

P=O.137 

733 (T) 

1/16 (6%) 

6.3% 

1/54 (2%) 

P=0.477N 

P=0.523N 

580 

8/16 (50%) 

62.3% 

16/53 (30%) 

P=O.559 

P=O.123 

P=O.150 

632 

0/16 (0%) 

9.7% 

3/53 (6%) 

P=O.118 

P=O.439 

P=O.419 

580 

8/16 (50%) 

66.0% 

19/53 (36%) 

P=O.316 

0116 (0%) 

0.0% 

0/53 (0%) 

P=0.505N 

P=0.500N 

P=0.500N 

- 

P=0.204N 

P=0.185N 

47 1 

6/18 (33%) 

46.2% 

12/53 (23 %) 

P=0.274N 

P=O.244 

P=O.253 

65 1 

1/18 (6%) 

8.5% 

2/53 (4%) 

P=O.243 

P=0.274N 

P=0.243N 

47 1 

7/18 (39%) 

50.7% 

13/53 (25%) 

P=0.354N 

P=0.740N 

P=0.722N 

711 

0/18 (0%) 

4.0% 

1/53 (2%) 

P=O.748 

Fisher exact test 

Cochran-Armitage test 

Logistic regression test 

Life table test 

First incidence (days) 

Terminal rate 

Adjusted rate 

Overall rate 

Lung: Squamous Cell Carcinoma, Alveolar/bronchiolar Adenoma, or Alveolarlbronchiolar Carcinoma 

P=O.234 

P=O.249 P=0.236N P=0.456N 

P=O.315 P=0.236N P=0.447N 

733 (T) 71 1 

2/16 (13%) 0116 (0%) 0/18 (0%) 

12.5% 0.0% 4.0% 

2/54 (4 %) 0/53 (0%) 1/53 (2%) 

- 

P=0.252N P=0.507N 

P=0.142N 

P=0.088N 

688 

7/21 (33%) 

43.3% 

11/53 (21 %) 

P=0.202N 

P=O.554 

P=O.554 

733 (T) 

1/21 (5%) 

4.8% 

1/53 (2%) 

P=O.495 

P=0.168N 

P=0.122N 

688 

8/21 (38%) 

47.4% 

12/53 (23%) 

P=0.274N 

P=O.325 

P=O.396 

628 

2/21 (10%) 

11.8% 

3/53 (6%) 

P=O.302 

11.8% 

3/53 (6%) 

P=O.532 

P=O.614 

628 

2/21 (10%) 

P=O.491 
Lesions in Male Rats 151 

(continued) 

Statistical Analysis of Primary Neoplasms in Male Rats in the 2-Year Inhalation Study of Nickel Sulfate Hexahydrate 

TABLE A3 

0 mg/m3 0.12 mg/m3 0.25 mg/m3 0.5 mg/m3 

Fisher exact test 

Cochran-Armitage test 

Logistic regression test 

Life table test 

First incidence (days) 

Terminal rate 

Adjusted rate 

Overall rate 

Oral Cavity (Oral Mucosa or Tongue): Squamous Cell Carcinoma 

0/16 (0%) 0/16 (0%) 1/18 (6%) 

0.0% 2.9% 13.4% 

0/54 (0%) 1/53 (2%) 3/53 (6%) 

P=O.629 

P=0.627N P=O.494 P=O.135 

P=0.590N P=O.518 P=O.151 

- 646 697 

P=O.495 P=O.118 

Overall rate 

Oral Cavity (Oral Mucosa or Tongue): Squamous Cell Papilloma or Squamous Cell Carcinoma 

2/54 (4%) 

Fisher exact test 

Cochran-Armitage test 

Logistic regression test 

Life table test 

First incidence (days) 

Terminal rate 

Adjusted rate 

Fisher exact test 

Cochran-Armitage test 

Logistic regression test 

Life table test 

First incidence (days) 

Terminal rate 

Adjusted rate 

Overall rate 

Oral Mucosa: Squamous Cell Carcinoma 

Fisher exact test 

Cochran-Armitage test 

Logistic regression test 

Life table test 

First incidence (days) 

Terminal rate 

Adjusted rate 

Overall rate 

Pancreatic Islets: Adenoma 

Fisher exact test 

Cochran-Armitage test 

Logistic regression test 

Life table test 

First incidence (days) 

Terminal rate 

Adjusted rate 

Overall rate 

Pancreatic Islets: Adenoma or Carcinoma 

P=0.238N 

P=0.234N 

P=0.211N 

577 

0/16 (0%) 

7.3% 

0/16 (0%) 

0.0% 

0/54 (0%) 

P=O.530 

P=O.553 

P=O.586 

- 

P=O.171 

P=O.171 

P=O.198 

657 

0/16 (0%) 

6.8% 

2/52 (4%) 

P=O.O82 

P=O.O80 

P=O.O97 

657 

0116 (0%) 

6.8% 

2/52 (4%) 

P=O.685 

P=0.655N 

640 

0/16 (0%) 

5.3% 

2/53 (4%) 

P=O.684 

0116 (0%) 

0.0% 

0153 (0%) 

- 

- 

- 

- 

P=0.491N 

P=0.466N 

704 

0/16 (0%) 

4.3% 

1/51 (2%) 

P=0.507N 

P=0.491N 

P=0.466N 

704 

0116 (0%) 

4.3% 

1/51 (2%) 

P=0.507N 

P=O.343 

P=O.377 

617 

1/18 (6%) 

15.8% 

4/53 (8%) 

P=O.330 

P=O.135 

P=O.151 

697 

1/18 (6%) 

13.4% 

3/53 (6%) 

P=O.118 

P=0.494N 

P=0.477N 

733 (T) 

1/17 (6%) 

5.9% 

1/52 (2%) 

P=0.500N 

P=0.693N 

P=0.679N 

614 

1/17 (6%) 

8.4% 

2/52 (4%) 

P=0.691N 

0121 (0%) 

0.0% 

0/53 (0%) 

- 

- 

- 

- 

0121 (0%) 

0.0% 

0153 (0%) 

P=0.241N 

P=0.224N 

- 

P=0.252N 

0/21 (0%) 

0.0% 

0153 (0%) 

- 

- 

- 

- 

P=O.353 

P=O.384 

630 

2/21 (10%) 

14.9% 

4/53 (8%) 

P=O.348 

2/21 (10%) 

5/53 (9%) 

17.4% 

P=O.228 

P=O.261 

630 

P=O.226 
152 Nickel Sulfate Hexahydrate, NTP TR 454 

(continued) 

Statistical Analysis of Primary Neoplasms in Male Rats in the 2-Year Inhalation Study of Nickel Sulfate Hexahydrate 

TABLE A3 

O mg/mJ 0.12 mg/m3 0.25 mg/m3 0.5 mg/m3 

Fisher exact test 

Cochran-Armitage test 

Logistic regression test 

Life table test 

First incidence (days) 

Terminal rate 

Adjusted rate 

Overall rate 

Pituitary Gland (Pars Distalis): Adenoma 

Fisher exact test 

Cochran-Armitage test 

Logistic regression test 

Life table test 

First incidence (days) 

Terminal rate 

Adjusted rate 

Overall rate 

Preputial Gland: Adenoma 

Fisher exact test 

Cochran-Armitage test 

Logistic regression test 

Life table test 

First incidence (days) 

Terminal rate 

Adjusted rate 

Overall rate 

Preputial Gland: Carcinoma 

Fisher exact test 

Cochran-Armitage test 

Logistic regression test 

Life table test 

First incidence (days) 

Terminal rate 

Adjusted rate 

Overall rate 

Preputial Gland: Adenoma or Carcinoma 

Fisher exact test 

Cochran-Armitage test 

Logistic regression test 

Life table test 

First incidence (days) 

Terminal rate 

Adjusted rate 

Overall rate 

Skin: Fibroma 

P=O.453 

P=O.472 

P=0.450N 

505 

3/16 (19%) 

42.5% 

13/54 (24%) 

P=O.222 

P=O.212 

P=O.266 

622 

0116 (0%) 

7.8% 

2/54 (4 X) 

P=0.444N 

P=0.462N 

P=0.446N 

482 

0116 (0%) 

1.9% 

1/54 (2%) 

P=O.379 

P=O.359 

P=O.418 

482 

0/16 (0%) 

9.6% 

3/54 (6%) 

0116 (0%) 

0.0% 

0/54 (0%) 

P=O.o44 

P=O.O44 

P=O.O60 

- 

P=0.526N 

P=0.452N 

547 

3/15 (20%) 

42.4% 

12/51 (24%) 18/53 (34%) 13/53 (25%) 

P=0.565N 

0116 (0%) 

0.0% 

0153 (0%) 

P=0.232N 

P=0.231N 

- 

P=0.252N 

P=O.250 

P=O.333 

607 

0116 (0%) 

8.0% 

3/53 (6%) 

P=O.302. 

P=O.625 

P=0.632N 

607 

0/16 (0%) 

8.0% 

3/53 (6%) 

P=O.652 

P=O.515 

P=O.518 

704 

0116 (0%) 

4.3% 

1/53 (2%) 

P=O.495 

P=O.196 

P=O.292 

432 

8/18 (44%) 

59.2% 

P=O.180 

P=O.476 

P=O.513 

538 

1/17 (6%) 

9.9% 

3/52 (6%) 

P=O.482 

P=O.736 

P=0.750N 

679 

0/17 (0%) 

3.2% 

1/52 (2%) 

P=O.743 

P=O.461 

P=O.518 

538 

1/17 (6%) 

12.8% 

4/52 (8%) 

P=O.479 

0118 (0%) 

0.0% 

0153 (0%) 

- 

- 

- 

- 

P=0.571N 

P=0.439N 

629 

6/21 (29%) 

45.1% 

P=O.567 

P=O.479 

P=O.543 

460 

1/21 (5%) 

8.9% 

3/53 (6%) 

P=O.491 

P=O.717 

P=O.756 

563 

0121 (0%) 

2.2% 

1/53 (2%) 

P=O.748 

P=O.452 

P=O.534 

460 

1121 (5%) 

10.9% 

4/53 (8%) 

P=O.489 

P=O.124 

P=O.161 

62 8 

1/21 (5%) 

10.5% 

3/53 (6%) 

P=O. 118 
Lesions in Male Rats 153 

(continued) 

Statistical Analysis of Primary Neoplasms in Male Rats in the 2-Year Inhalation Study of Nickel Sulfate Hexahydrate 

TABLE A3 

0 mg/m3 0.12 mg/m3 0.25 mg/m3 0.5 mg/m3 

Fisher exact test 

Cochran-Armitage test 

Logistic regression test 

Life table test 

First incidence (days) 

Terminal rate 

Adjusted rate 

Overall rate 

Skin: Fibroma or Sarcoma 

Fisher exact test 

Cochran-Armitage test 

Logistic regression test 

Life table test 

First incidence (days) 

Terminal rate 

Adjusted rate 

Overall rate 

Skin: Keratoacanthoma 

Fisher exact test 

Cochtan-Armitage test 

Logistic regression test 

Life table test 

First incidence (days) 

Terminal rate 

Adjusted rate 

Overall rate 

or Squamous Cell Carcinoma 

Skin: Squamous Cell Papilloma, Keratoacanthoma, 

Fisher exact test 

Cochran-Armitage test 

Logistic regression .test 

Life table test 

First incidence (days) 

Terminal rate 

Adjusted rate 

Overall rate 

Testes: Adenoma 

Fisher exact test 

Cochran-Armitage test 

Logistic regression test 

Life table test 

First incidence (days) 

Terminal rate 

Adjusted rate 

Overall rate 

Thyroid Gland (Ccell): 

0116 (0%) 

0.0% 

0154 (0%) 

P=O.O53 

P=O.O55 

P=O.O73 

P=0.036N 

P=0.031N 

P=0.030N 

679 

1/16 (6%) 

17.2% 

4/54 (7%) 

Trichoepithelioma, 

P=O.527 

P=O.544 

P=0.518N 

679 

1/16 (6%) 

17.2% 

4/54 (7%) 

P=O.O63 

P=O.O32 

P=0.432N 

482 

16/16 (100%) 

100.0% 

45/54 (83 46) 

Adenoma 

P=0.016N 

P=0.013N 

P=0.008N 

577 

4/16 (25%) 

37.6% 

8/53 (15%) 

1/53 (2%) 1/53 (2%) 3/53 (6%) 

4.3% 4.0% 10.5% 

0116 (0%) 0/18 (0%) 1/21 (5%) 

704 711 628 

P=O.518 P=O.545 P=O.161 

P=O.515 P=O.514 P=O.124 

P=O.495 P=O.495 P=O.118 

1/53 (2%) 1/53 (2%) 0153 (0%) 

4.3% 3.6% 0.0% 

0/16 (0%) 0118 (0%) 0121 (0%) 

704 685 

P=O. 167N P=0.151N P=0.055N 

P=0.084N P=O.lSON P=O.O56N 

- 

Basal Cell Adenoma or Carcinoma, 

3/53 (6%) 3/53 (6%) 4/53 (8 X) 

13.4% 14.3% 15.1 % 

1/16 (6%) 2/18 (11%) 2/21 (10%) 

683 685 419 

P=0.465N P=0.436N P=0.566N 

P=0.343N P=0.465N P=0.638N 

P=0.511N P=0.511N P=O.632 

46/53 (87%) 45/53 (85%) 50/53 (94%) 

97.8% 97.8% 98.0% 

15/16 (94%) 17/18 (94%) 20/21 (95%) 

539 538 320 

P=0.474N P=0.367N P=0.468N 

P=0.535N P=O.624 P=O.O63 

P=O.409 P=O.517 P=O.O66 

1/53 (2%) 2/51 (4%) 1/52 (2%) 

6.3% 6.8% 4.8% 

1/16 (6%) 0118 (0%) 1/21 (5%) 

733 (T) 538 733 (T) 

P=O.O18N P=0.036N P=0.008N 

P=0.012N P=0.046N P=0.012N 
154 Nickel Sulfate Hexahydrate, NTP TR 454 

(continued) 

Statistical Analysis of Primary Neoplasms in Male Rats in the 2-Year Inhalation Study of Nickel Sulfate Hexahydrate 

TABLE A3 

O mg/m’ 0.12 mg/m3 0.25 mg/m3 0.5 mg/m3 

Fisher exact test 

Cochran-Armitage test 

Logistic regression test 

Life table test 

First incidence (days) 

Terminal rate 

Adjusted rate 

Overall rate 

Thyroid Gland (C-cell): Adenoma or Carcinoma 

Fisher exact test 

Cochran-Armitage test 

Logistic regression test 

Life table test 

First incidence (days) 

Terminal rate 

Adjusted rate 

Overall rate 

All Organs: Mononuclear Cell Leukemia 

Fisher exact test 

Cochran-Armitage test 

Logistic regression test 

Life table test 

First incidence (days) 

Terminal rate 

Adjusted rate 

Overall rate 

AU Organs: Benign Neoplasms 

Fisher exact test 

Cochran-Armitage test 

Logistic regression test 

Life table test 

First incidence (days) 

Terminal rate 

Adjusted rate 

Overall rate 

All Organs: Malignant Neoplasms 

P=0.104N 

P=0.092N 

P=0.062N 

577 

4/16 (25%) 

37.6% 

8/53 (15%) 

P=O.O86 

P=O.O48 

P=O.450 

496 

10/16 (63%) 

81.4% 

31/54 (57%) 

P=O.281 

P=O.215 

P=0.249N 

482 

16/16 (100%) 

100.0% 

50154 (93 %) 

P=O.257 

P=O.276 

P=0.383N 

262 

12/16 (75%) 

88.8% 

37/54 (69%) 

P=0.034N 

P=0.046N 

643 

1/16 (6%) 

8.8% 

2/53 (4%) 

P=0.046N 

P=O.243 

P=O.383 

539 

12/16 (75%) 

89.0% 

36/53 (68 %) 

P=O.178 

P=0.618N 

P=0.410N 

539 

16/16 (100%) 

100.0% 

50/53 (94%) 

P=O.511 

P=O.136 

P=O.361 

539 

13/16 (81%) 

93.1% 

43/53 (81 %) 

P=O.100 

P=0.046N 

P=0.036N 

538 

0118 (0%) 

6.8% 

2/51 (4%) 

P=0.053N 

P=O.108 

P=O.329 

55 1 

14/18 (78%) 

90.1 % 

38/53 (72%) 

P=O.O90 

P=O.647 

P=0.376N 

432 

18/18 (100%) 

100.0% 

50153 (94%) 

P=O.511 

P=O.169 

P=O.447 

279 

14/18 (78%) 

90.8% 

41/53 (77%) 

P=O.149 

P=0.077N 

P=0.054N 

67 1 

2/21 (10%) 

12.5% 

3/52 (6%) 

P=0.107N 

P=O.O52 

P=O.424 

539 

13/21 (62%) 

82.2% 

38/53 (72%) 

P=O.O90 

P=O.423 

P=0.275N 

320 

21/21 (100%) 

100.0% 

51/53 (96%) 

P=O.348 

P=O.232 

P=0.494N 

320 

15/21 (71%) 

86.9% 

41/53 (77%) 

P=O.209 
Lesions in Male Rats 155 

(continued) 

Statistical Analysis of Primary Neoplasms in Male Rats in the 2-Year Inhalation Study of Nickel Sulfate Hexahydrate 

TABLE A3 

O mg/m3 0.12 mg/m3 0.25 mglm3 0.5 mg/m3 

Fisher exact test 

Cochran-Armitage test 

Logistic regression test 

Life table test 

First incidence (days) 

Terminal rate 

Adjusted rate 

Overall rate 

All Organs: Benign or Malignant Neoplasms 

P=0.331N 

P=0.196N P=0.394N P=0.306N P=0.283N 

P=0.149N P=0.363N P=0.294N P=0.171N 

262 363 279 320 

16/16 (100%) 16/16 (100%) 18/18 (100%) 21/21 (100%) 

100.0% 100.0% 100.0% 100.0% 

53/54 (98 %) 52/53 (98 %) 51/53 (96%) 51/53 (96%) 

P=0.748N P=0.493N P=0.493N 

a Number of neoplasm-bearing animalslnumber of animals examined. Denominator is number of animals examined microscopically for adrenal gland, lung, 

(T)Terminal sacrifice 

compare directly the overall incidence rates. For all tests, a negative trend or a lower incidence in an exposure group is indicated by N. 

(directly or indirectly) the cause of death. The logistic regression test regards these lesions as nonfatal. The Cochran-Armitage and Fisher exact tests 

painvise comparisons between the controls and that exposed group. The life table test regards neoplasms in animals dying prior to terminal kill as being 

Beneath the control incidence are the P values associated with the trend test. Beneath the exposed group incidence are the P values corresponding to 

Observed incidence at terminal kill 

Kaplan-Meier estimated neoplasm incidence at the end of the study after adjustment for intercurrent mortality 

pancreatic islets, pituitary gland, preputial gland, testis, and thyroid gland; for other tissues, denominator is number of animals necropsied. 

e Not applicable; no neoplasms in animal group 
156 Nickel Sulfate Hexahydrate, NTP TR 454 

Historical Incidence of Lung Neoplasms in Untreated Male F344/N Ratsa 

TABLE A4 

Study 

Incidence in Controls 

Carcinoma 

Carcinoma Carcinoma or Squamous Cell 

Alveolarhronchiolar 

Alveolarhronchiolar Alveolarhronchiolar Squamous Cell Adenoma or Carcinoma 

Adenoma 

Historical Incidence at Lovelace Inhalation Toxicology Research Institute 

Talcb 

Nickel Sulfate Hexahydrate 

Nickel Subsulfide 

Nickel Oxide 

0149 

0154 

0153 

0154 

0149 

1/54 

0/53 

0154 

0149 

1154 

0153 

1154 

0149 

2/54 

0153 

1/54 

Overall Historical Incidence in Inhalation Studies 

Range 

Standard deviation 

Total 

0%-10% 

3.5% 

171703 (2.4%) 61703 (0.9%) 41703 (0.6%) 

1 .O% 0.9% 

0%-2% 0%-2% 0%-10% 

3.8% 

271703 (3.8%) 

Overall Historical Incidence in Feed Studies 

Range 

Standard deviation 

Total 

0%-6% 

2.0% 

2811,200 (2.3%) 

0%-4% 

1.2% 

1111,200 (0.9%) 0/1,200 (0%) 

0%-8% 

2.0% 

3911.200 (3.3%) 

Results of lifetime study 

a Data as of 17 June 1994 
Lesions in Male Rats 157 

of Nickel Sulfate Hexahydratea 

Summary of the Incidence of Nonneoplastic Lesions in Male Rats in the 2-Year Inhalation Study 

TABLE A5 

0 mg/m3 0.12 mg/m3 0.25 mg/m3 0.5 mg/m3 

Early deaths 

15-Month interim evaluation 

%Month interim evaluation 

Animals initially in study 

Disposition Summary 

Natural deaths 

Moribund 

Accidental death 

Terminal sacrifice 

Died last week of study 

Survivors 

5 

5 

64 

4 

34 

16 

5 

5 

63 

7 

30 

16 

5 

5 

63 

3 

31 

1 

18 

5 

5 

63 

4 

28 

20 

1 

Animals examined microscopically 64 63 63 63 

Lymph node, bronchial 

Hematopoietic System 

7-Month Interim Evaluation 

Hyperplasia, lymphoid 

Lymph node, mediastinal 

Hyperplasia, lymphoid 

Congestion 

Thymus 

(3) 

(5) 

(5) 

(5) 

(1) 

(4) 

(5) 

(4) 

(5) 

4 (80%) 

5 (100%) 

1 (100%) 

2 (50%) 

2 (40%) 

2 (50%) 

5 (100%) 

Lung 

Respiratory System 

Interstitium, infiltration cellular 

Bronchus, hyperplasia, lymphoid 

Alveolar epithelium, hyperplasia, focal 

Inflammation. chronic active 

Hyperplasia, macrophage 

Respiratory epithelium, metaplasia, squamous 

Respiratory epithelium, hyperplasia 

Respiratory epithelium, degeneration 

Olfactory epithelium, degeneration 

Olfactory epithelium, atrophy 

Nose 

(5) (5) 

4 (80%) 

1 (20%) 

4 (80%) 

5 (100%) 

2 (40%) 5 (100%) 

1 (20%) 

5 (100%) 

(5) (5) (5) 

1 (20%) 

1 (20%) 

1 (20%) 

(5) 

5 (100%) 

2 (40%) 

1 (20%) 

5 (100%) 

5 (100%) 

1 (20%) 

1 (20%) 

1 (20%) 

1 (20%) 

(5) 

Calculus, microscopic observation only 

Urinary bladder 

Nephropathy 

Kidney 

Urinary System 

(5) 

a Number of animals examined microscopically at the site and the number of animals with. lesion 
158 Nickel Sulfate Hexahydrate, NTP TR 454 

of Nickel Sulfate Hexahydrate (continued) 

Summary of the Incidence of Nonneoplastic Lesions in Male Rats in the 2-Year Inhalation Study 

TABLE A5 

0 mg/m3 0.12 mg/m3 0.25 mg/m3 OS mg/mg 

Special Senses System 

Nervous System 

Musculoskeletal System 

Integumentary System 

Genital System 

General Body System 

Endocrine System 

Cardiovascular System 

Alimentary System 

Systems Examined With No Lesions Observed 

?Month Interim Evaluation (continued) 

Intestine large, colon 

Alimentary System 

15-Month Interim Evaluation 

Parasite metazoan 

Intestine large, cecum 

Parasite metazoan 

Intestine large, rectum 

Parasite metazoan 

Hepatodiaphragmatic nodule 

Degeneration, cystic 

Basophilic focus 

Liver 

Acinus, atrophy 

Inflammation, focal 

(5) 

(5) 

(5) 

(5) 

(5) 

(5) 

(5) 

(5) 

(5) 

(5) 

(5) 

(5) 

(5) 

(5) 

(5) 

(5) 

1 (20%) 

1 (20%) 2 (40%) 

4 (80%) 

1 (20%) 

1 (20%) 

1 (20%) 

1 (20%) 

5 (100%) 

1 (20%) 

1 (20%) 

1 (20%) 

1 (20%) 

5 (100%) 

2 (40%) 

1 (20%) 

2 (40%) 

Pancreas (5) (5) (5) (5) 

1 (20%) 

Pars distalis, hyperplasia, focal 

Pituitary gland 

Hyperplasia 

Adrenal cortex 

Endocrine System 

cyst 

Germinal epithelium, degeneration 

Testes 

Inflammation 

Prostate 

Genital System 

(5) 

(5) 

(5) 

(4) 

(5) 

(5) 

(5) 

(5) 

1 (20%) 1 (25%) 

1 (20%) 

2 (40%) 1 (20%) 

cyst 

Thymus 

Hyperplasia, lymphoid 

Lymph node, bronchial 

Hyperplasia 

Bone marrow 

Hematopoietic System 
Lesions in Male Rats 159 

of Nickel Sulfate Hexahydrate (continued) 

Summary of the Incidence of Nonneoplastic Lesions in Male Rats in the 2-Year Inhalation Study 

TABLE A5 

O mg/m3 0.12 mg/m3 0.25 mg/m3 0.5 mg/m3 

Lung 

Respiratory System 

15-Month Interim Evaluation (continued) 

(5) 

Interstitium, infiltration cellular 

Alveolus, proteinosis 

Alveolar epithelium, hyperplasia, focal 

Inflammation, chronic active 

Hyperplasia, macrophage 

Fibrosis 

Respiratory epithelium, inflammation 

Respiratory epithelium, degeneration 

Olfactory epithelium, inflammation 

Olfactory epithelium, degeneration 4 (80%) 

1 (20%) 

Nose (5) 

1 (20%) 

1 (20%) 

1 (20%) 

2 (40%) 

1 (20%) 

(5) (5) 

3 (60%) 1 (20%) 

1 (20%) 

1 (20%) 

1 (20%) 

(5) 

5 (100%) 

5 (100%) 

2 (40%) 

4 (80%) 

1 (20%) 

1 (20%) 

Calculus, microscopic observation only 2 (40%) 

Urinary bladder 

Nephropathy 5 (100%) 

Kidney 

Urinary System 

(5) 

(5) 

(5) 

(5) 

(5) 

(5) 

(5) 

(5) 

4 (80%) 

5 (100%) 

2 (40%) 

4 (80%) 

1 (20%) 

5 (100%) 

Special Senses System 

Nervous System 

Musculoskeletal System 

Integumentary System 

General Body System 

Cardiovascular System 

Systems Examined With No Lesions Observed 

2- Year Study 

Alimentary System 

Parasite metazoan 

Autolysis 

Intestine large, colon 

Autolysis 

Intestine large, cecum 

Autolysis 

Intestine large, rectum 

Ulcer 

Autolysis 

Intestine small, duodenum 

Autolysis 

Peyer’s patch, hyperplasia 

Autolysis 

Intestine small, jejunum 

Intestine small, ileum 

(54) 

1 (2%) 

(54) 

2 (4%) 

(54) 

(53) 

1 (2%) 

1 (2%) 

1 (2%) 

1 (2%) 

2 (4%) 

(53) 

(53) 

(53) 

1 (2%) 4 (8%) 

(48) (53) 
160 

of Nickel Sulfate Hexahydrate (continued) 

Summary of the Incidence of Nonneoplastic Lesions in Male Rats in the 2-Year Inhalation Study 

TABLE A5 

0 mg/m3 0.12 mg/m3 0.25 mg/m3 0.5 mg/m3 

Liver 

Alimentary System (continued) 

2-Year Study (continued) 

Hepatocyte, necrosis 

Hepatocyte, hyperplasia 

Centrilobular, atrophy 

Bile duct, hyperplasia 

Thrombosis 

Mixed cell focus 

Infarct 

Hepatodiaphragmatic nodule 

Hematopoietic cell proliferation 

Fatty change 

Eosinophilic focus 

Degeneration, fatty 

Degeneration, cystic 

cyst 

Congestion 

Clear cell focus 

Basophilic focus 

Autolysis 

Angiectasis 

Mesentery 

cyst 

Atrophy, focal 

Hyperplasia, squamous 

Fat, necrosis 

Acinus, hyperplasia 

Acinus, atrophy 

Thrombosis 

Polyarteritis 

Infarct 

Cytoplasmic alteration 

Autolysis 

Ulcer 

Perforation 

Inflammation 

Hyperplasia, squamous 

Edema 

Diverticulum 

Stomach, forestomach 

Ulcer 

Necrosis 

Inflammation 

Erosion 

Autolysis 

Peridontal tissue, inflammation 

Peridontal tissue, hyperplasia 

Developmental malformation 

Pancreas 

Oral mucosa 

- 

Stomach, glandular 

Tooth 

(54) 

6 (11%) 

5 (9%) 

6 (11%) 

11 (20%) 

1 (2%) 

2 (4%) 

2 (4%) 

32 (59%) 

(2) 

16 (30%) 

1 (2%) 

6 (11%) 

36 (67%) 

4 (7%) 

2 (4%) 

1 (2%) 

4 (7%) 

1 (33%) 

1 (50%) 

(53) 

(3) 

1 (2%) 

1 (2%) 

5 (9%) 

(54) 

4 (7%) 

1 (2%) 

1 (2%) 

1 (2%) 

(54) 

(9) 

1 (2%) 

1 (2%) 

9 (100%) 

(53) 

5 (9%) 

28 (53%) 

1 (2%) 

11 (21%) 

7 (13%) 

5 (9%) 

12 (23%) 

2 (4%) 

1 (25%) 

(4) 

18 (34%) 

2 (4%) 

4 (8%) 

33 (62%) 

1 (2%) 

3 (6%) 

(2) 

1 (50%) 

(52) 

1 (2%) 

1 (2%) 

6 (12%) 

(53) 

2 (4%) 

1 (2%) 

1 (2%) 

(53) 

3 (100%) 

(53) 

2 (4%) 

2 (4%) 

41 (77%) 

2 (4%) 

4 (8%) 

1 (2%) 

5 (9%) 

12 (23%) 

7 (13%) 

5 (9%) 

12 (23%) 

1 (2%) 

5 (9%) 

37 (70%) 

(53) 

(4) 

2 (4%) 

1 (2%) 

9 (17%) 

(52) 

2 (4%) 

(53) 

1 (2%) 

1 (2%) 

1 (33%) 

1 (33%) 

2 (67%) 

(3) 

(53) 

4 (8%) 

35 (66%) 

10 (19%) 

5 (9%) 

8 (15%) 

8 (15%) 

7 (13%) 

1 (2%) 

7 (13%) 

35 (66%) 

1 (2%) 

1 (2%) 

(1) 

16 (30%) 

(53) 

1 (2%) 

6 (11%) 

1 (2%) 

1 (2%) 

(52) 

1 (2%) 

1 (2%) 

(53) 

1 (2%) 

(3) 

3 (100%) 
Lesions in Male Rats 161 

of Nickel Sulfate Hexahydrate (continued) 

Summary of the Incidence of Nonneoplastic Lesions in Male Rats in the 2-Year Inhalation Study 

TABLE A5 

0 mg/m3 0.12 mg/m3 0.25 mg/m3 0.5 mg/m3 

Heart 

Cardiovascular Syltem 

%Year Study (continued) 

(54) (53) (53) (53) 

Epicardium, inflammation 

Atrium, thrombosis 

Thrombosis 

Proliferation connective tissue 

Inflammation 

Infarct 

Fibrosis 

Cardiomyopathy 

Autolysis 1 (2%) 

31 (57%) 31 (58%) 29 (55%) 

1 (2%) 

1 (2%) 

32 (60%) 

5 (9%) 

1 (2%) 

5 (9%) 

1 (2%) 

1 (2%) 

8 (15%) 

1 (2%) 

2 (4%) 

Endocrine System 

Capsule, fibrosis 

Vacuolization cytoplasmic 

Hypertrophy 

Hyperplasia 

Degeneration, cystic 

Cytoplasmic alteration 

Autolysis 

Atrophy 

Adrenal cortex 

Hyperplasia 

Hemorrhage 

cyst 

Autolysis 

Parathyroid gland 

Hyperplasia 

Islets, pancreatic 

Angiectasis 

Pituitary gland 

Bilateral, hyperplasia 

Hyperplasia 

Pars distalis, hyperplasia, focal 

Pars distalis, hyperplasia, diffuse 

Pigmentation, ceroid 

Hemorrhage 

Follicular cell, hyperplasia, cystic 

C-cell, hyperplasia 

Autolysis 

Thyroid gland 

(54) (53) (53) (53) 

1 (2%) 

10 (19%) 

6 (11%) 

1 (2%) 

3 (6%) 1 (2%) 

1 (2%) 

16 (30%) 

4 (8%) 

1 (2%) 

11 (20%) 

1 (2%) 

3 (6%) 

17 (32%) 

4 (8%) 

1 (2%) 

1 (2%) 

Adrenal medulla (54) (53) (53) (53) 

3 (6%) 

2 (4%) 

28 (52%) 

1 (2%) 

1 (2%) 

2 (4%) 

2 (4%) 

20 (38%) 

1 (2%) 

2 (4%) 

18 (34%) 

2 (4%) 

4 (8%) 

26 (49%) 

1 (2%) 

1 (2%) 

2 (4%) 

1 (2%) 

(52) (51) (52) 

(48) 

(53) 

(49) (51) (51) 

(54) (51) (53) (53) 

1 (2%) 

3 (6%) 7 (14%) 3 (6%) 

cyst 

7 (13%) 

1 (2%) 

15 (29%) 

2 (4%) 

14 (26%) 15 (28%) 16 (30%) 

(53) (53) (5 1) (52) 

8 (16%) 

1 (2%) 

6 (12%) 

1 (2%) 

1 (2%) 

5 (9%) 

Tissue NOS 

General Body System 

Pelvic, ectopic tissue 

Oral, inflammation 

Mediastinum, polyarteritis 

Hemorrhage 

(4) 

1 (25%) 

1 (20%) 
162 Nickel Sulfate Hexahydrate, NTP TR 454 

of Nickel Sulfate Hexahydrate (continued) 

Summary of the Incidence of Nonneoplastic Lesions in Male Rats in the 2-Year Inhalation Study 

TABLE A5 

0 mg/d 0.12 mg/m3 0.25 mg/m3 0.5 mg/m3 

Coagulating gland 

Genital System 

&Year Study (continued) 

Inflammation 

Spermatocele 

Granuloma sperm 

Epididymis 

Inflammation 

Penis 

Inflammation 

Infiltration cellular 

Hyperplasia 

Ectasia 

Autolysis 

Atrophy 

Preputial gland 

Inflammation 

Prostate 

Inflammation 

Hyperplasia, cystic 

Hyperplasia 

Ectasia 

Autolysis 

Atrophy 

Seminal vesicle 

Interstitial cell, hyperplasia, focal 

Infarct 

cyst 

Atrophy 

Testes 

(53) 

1 (2%) 

1 (2%) 

(54) 

(1) 

2 (4%) 

1 (2%) 

1 (100%) 

2 (4%) 

1 (2%) 

3 (6%) 

(54) 

(53) 

2 (4%) 

(52) 

1 (2%) 

5 (10%) 

1 (2%) 

2 (4%) 

5 (9%) 5 (9%) 

2 (4%) 

2 (4%) 

2 (4%) 

(53) 

(53) 

,3 (6%) 

3 (6%) 

5 (9%) 

(53) 

(53) 

7 (13%) 

2 (4%) 

1 (2%) 

1 (2%) 

(53) 

(53) 

(54) 

2 (4%) 

1 (2%) 

1 (2%) 

1 (2%) 

1 (2%) 

(53) 

1 (2%) 

3 (6%) 10 (19%) 

1 (2%) 

(53) (53) 

4 (8%) 

(54) 

1 (2%) 

7 (13%) 

5 (9%) 

1 (2%) 

11 (20%) 7 (13%) 6 (11%) 

Hematopoietic System 

Myeloid cell, hyperplasia 

Erythroid cell, hyperplasia 

Atrophy, focal 

Atrophy 

Bone marrow 

Renal, pigmentation, hemosiderin 

Renal, inflammation 

Pancreatic, pigmentation, hemosiderin 

Pancreatic, inflammation 

Inguinal, inflammation, granulomatous 

Inguinal, hyperplasia, lymphoid 

Inguinal, hyperplasia, histiocytic 

Iliac, pigmentation 

Iliac, hyperplasia, plasma cell 

Lymph node 

(53) 

1 (2%) 

1 (8%) 

1 (8%) 

18 (34%) 

(12) 

(54) 

17 (31%) 

2 (4%) 

1 (2%) 

1 (2%) 

(1 1) 

1 (9%) 

1 (9%) 

1 (7%) 

1 (8%) 

1 (8%) 

1 (9%) 

1 (9%) 
Lesions in Male Rats 163 

of Nickel Sulfate Hexahydrate (continued) 

Summary of the Incidence of Nonneoplastic Lesions in Male Rats in the 2-Year Inhalation Study 

TABLE A5 

0 mg/m3 0.25 mg/m3 0.5 mg/m3 

Lymph node, bronchial 

Hematopoietic System (continued) 

2- Year Study (continued) 

Inflammation 

Hyperplasia, plasma cell 

Hyperplasia, lymphoid 

Edema 

Congestion 

Autolysis 

Inflammation 

Hyperplasia, plasma cell 

Hyperplasia, lymphoid 

Lymph node, mandibular 

Pigmentation, hemosiderin 

Hyperplasia, lymphoid 

Congestion 

Autolysis 

Pigmentation, hemosiderin 

Pigmentation 

Hyperplasia, plasma cell 

Hyperplasia, macrophage 

Hyperplasia, lymphoid 

Edema 

Congestion 

Autolysis 

Lymph node, mediastinal 

Pigmentation, hemosiderin 

Infarct 

Hyperplasia, lymphoid 

Hemorrhage 

Hematopoietic cell proliferation 

Fibrosis 

Congestion 

Autolysis 

Atrophy 

Angiectasis 

cyst 

Congestion 

Autolysis 

Atrophy 

Thymus 

Lymph node, mesenteric 

Spleen 

1 (2%) 

5 (10%) 

2 (4%) 

(52) 

1 (2%) 

1 (2%) 

1 (2%) 

1 (2%) 

(51) 

1 (2%) 

3 (6%) 

13 (24%) 

5 (9%) 

1 (2%) 

1 (2%) 

(49) 

1 (2%) 

1 (2%) 

(53) 

2 (4%) 

3 (6%) 

(53) 

1 (2%) 

1 (2%) 

(49) 

2 (4%) 

2 (4%) 

1 (2%) 

1 (2%) 

3 (6%) 

2 (4%) 

2 (4%) 

1 (2%) 

2 (4%) 

1 (2%) 

(53) 

16 (30%) 

2 (4%) 

1 (2%) 

(49) (48) 

16 (33%) 13 (27%) 

1 (2%) 

1 (2%) 

1 (2%) 

(47) 

2 (4%) 

3 (6%) 

(52) 

1 (2%) 

6 (12%) 

9 (17%) 

(53) 

2 (4%) 

(46) 

1 (2%) 

5 (11%) 

3 (7%) 

(51) 

1 (2%) 

1 (2%) 

14 (27%) 

1 (2%) 

1 (2%) 

(48) 

10 (21%) 

(52) 

1 (2%) 

10 (19%) 

2 (4%) 

1 (2%) 

(53) 

1 (2%) 

1 (2%) 

6 (11%) 

(53) 

(50) 

4 (8%) 

2 (4%) 

1 (2%) 

7 (14%) 

2 (4%) 

1 (2%) 

(53) 

14 (26%) 

1 (2%) 

1 (2%) 

2 (4%) 

1 (2%) 

1 (2%) 

(46) 

17 (37%) 

1 (2%) 
164 Nickel Sulfate Hexahydrate, NTP TR 454 

of Nickel Sulfate Hexahydrate (continued) 

Summary of the Incidence of Nonneoplastic Lesions in Male Rats in the 2-Year Inhalation Study 

TABLE A5 

0 mg/m3 0.12 rng/m3 0.25 mg/m3 0.5 mg/m3 

Mammary gland 

Integumentary System 

2-Year Study (continued) 

Hemorrhage 

Sebaceous gland, inflammation 

Prepuce, fibrosis 

Necrosis 

Inflammation 

Hyperkeratosis 

Edema 

Cyst epithelial inclusion 

Angiectasis 

Skin (53) 

(43) 

(53) 

(48) 

(53) 

(49) 

(53) 

(44) 

1 (2%) 

1 (2%) 

3 (6%) 1 (2%) 

1 (2%) 

1 (2%) 

2 (4%) 

1 (2%) 

2 (4%) 

1 (2%) 

1 (2%) 

Musculoskeletal System 

Hyperostosis 

Fibrous osteodystrophy 

Bone (54) (53) (53) (53) 

2 (4%) 

1 (2%) 

1 (2%) 1 (2%) 

Nervous System 

Ventricle, hydrocephalus 

Necrosis 

Infiltration cellular, histiocyte 

Infarct 

Hydrocephalus 

Hemorrhage 

Degeneration 

Compression 

Brain (54) (53) (53) (53) 

3 (6%) 

.5 (9%) 

1 (2%) 

1 (2%) 

1 (2%) 

1 (2%) 

2 (4%) 

2 (4%) 

5 (9%) 

1 (2%) 

5 (9%) 

1 (2%) 

5 (9%) 

1 (2%) 

1 (2%) 

1 (2%) 

Larynx 

Respiratory System 

(54) (52) (53) (53) 

Necrosis 

Metaplasia, squamous 

Inflammation 

Hyperplasia 

Interstitium, infiltration cellular 11 (20%) 

Alveolus, proteinosis 

Alveolar epithelium, hyperplasia, focal 3 (6%) 

Metaplasia, osseous 1 (2%) 

Inflammation, suppurative 

Inflammation, chronic active 

Hyperplasia, macrophage 

Hemorrhage 

Fibrosis 

Emphysema 

Congestion 

Autolysis 

1 (2%) 

13 (25%) 

3 (6%) 

8 (15%) 9 (17%) 

1 (2%) 

8 (15%) 

Lung (54) (53) (53) (53) 

11 (21%) 

9 (17%) 

5 (9%) 

6 (11%) 

1 (2%) 

3 (6%) 

1 (2%) 

2 (4%) 

14 (26%) 

7 (13%) 

2 (4%) 

3 (6%) 

2 (4%) 1 (2%) 

42 (79%) 

35 (66%) 

1 (2%) 

35 (66%) 

1 (2%) 

46 (87%) 

48 (91%) 

1 (2%) 

43 (81%) 

11 (21%) 

41 (77%) 

2 (4%) 

2 (4%) 

2 (4%) 

3 (6%) 

12 (23%) 

3 (6%) 
Lesions in Male Rats 165 

of Nickel Sulfate Hexahydrate (continued) 

Summary of the Incidence of Nonneoplastic Lesions in Male Rats in the 2-Year Inhalation Study 

TABLE A5 

Nose 

Respiratory System (continued) 

&Year Study (continued) 

Vomeronasal organ, inflammation 

Respiratory epithelium, metaplasia, squamous 

Respiratory epithelium, inflammation 

Respiratory epithelium, hyperplasia 

Respiratory epithelium, degeneration 

Olfactory epithelium, necrosis 

Olfactory epithelium, metaplasia, squamous 

Olfactory epithelium, inflammation 

Olfactory epithelium, degeneration 

Olfactory epithelium, atrophy 

Nasopharyngeal duct, inflammation 

Nasopharyngeal duct, hyperplasia, lymphoid 

Nasopharyngeal duct, hyperplasia 

Nasolacrimal duct, inflammation 

Nasolacrimal duct, hyperplasia 

Glands, inflammation 

Thrombosis, multiple 

Thrombosis 

(54) 

8 (15%) 

4 (7%) 

35 (65%) 

2 (4%) 

1 (2%) 

2 (4%) 

14 (26%) 

18 (33%) 

2 (4%) 

(52) 

1 (2%) 

6 (12%) 

4 (8%) 

1 (2%) 

2 (4%) 

4 (8%) 

16 (31%) 

1 (2%) 

2 (4%) 

12 (23%) 

16 (31%) 

(53) 

1 (2%) 

4 (8%) 

4 (8%) 

4 (8%) 

1 (2%) 

1 (2%) 

13 (25%) 

3 (6%) 

2 (4%) 

1 (2%) 

2 (4%) 

17 (32%) 

27 (51%) 

1 (2%) 

(53) 

3 (6%) 

1 (2%) 

8 (15%) 

1 (2%) 

14 (26%) 

7 (13%) 

1 (2%) 

1 (2%) 

34 (64%) 

6 (11%) 

24 (45%) 

Eye 

Special Senses System 

Synechia 

Retinal detachment 

Cataract 

(1) 

1 (100%) 

1 (100%) 

1 (100%) 

1 (100%) 

Urinary System 

Renal tubule, pigmentation 

Nephropathy 

Inflammation 

Infarct 

cyst 

Autolysis 

Kidney 

Calculus, microscopic observation only 

Autolysis 

Calculus, microscopic observation only 

Urinary bladder 

UEthra 

1 (2%) 

2 (4%) 

1 (100%) 

(1) 

7 (13%) 

50 (93%) 

(54) 

1 (2%) 

7 (13%) 

45 (87%) 

1 (2%) 

2 (4%) 

1 (2%) 

I (2%) 

(53) 

3 (100%) 

(3) 

(52) 

2 (4%) 

8 (15%) 

45 (87%) 

1 (2%) 

2 (4%) 

4 (8%) 

1 (2%) 

(53) 

(1) 

39 (74%) 

1 (100%) 

8 (15%) 

2 (4%) 
166 Nickel Sulfate Hexahydrate, NTP TR 454 
167 

OF NICKEL SULFATE HEXAHYDRATE 

SUMMARY OF LESIONS IN FEMALE RATS 

APPENDIX B 

IN THE 2-YEAR INHALATION STUDY 

TABLE B5 Summary of the Incidence of Nonneoplastic Lesions in Female Rats 

TABLE B4 Historical Incidence of Lung Neoplasms 

TABLE B3 Statistical Analysis of Primary Neoplasms in Female Rats 

TABLE B2 Individual Animal Tumor Pathology of Female Rats 

TABLE B1 Summary of the Incidence of Neoplasms in Female Rats 

in the 2-Year Inhalation Study of Nickel Sulfate Hexahydrate 

in Untreated Female F344/N Rats 

in the 2-Year Inhalation Study of Nickel Sulfate Hexahydrate 

in the 2-Year Inhalation Study of Nickel Sulfate Hexahydrate 

in the 2-Year Inhalation Study of Nickel Sulfate Hexahydrate ................ 

198 

197 

192 

174 

169 

................ 

................ 

.................................. 

................ 
168 Nickel Sulfate Hexahydrate, NTP TR 454 
Lesions in Female Rats 169 

Summary of the Incidence of Neoplasms in Female Rats in the 2-Year Inhalation Study of Nickel Sulfate Hexahydratea 

TABLE B1 

O mg/m3 0.12 mg/m3 0.25 mg/m3 0.5 mg/m3 

Early deaths 

15-Month interim evaluation 

%Month interim evaluation 

Animals initially in study 

Disposition Sumqary 

Natural deaths 

Moribund 

Accidental death 

Terminal sacrifice 

Missexed 

Missing 

Survivors 

Animals examined microscopically 

5 

5 

63 

4 

27 

22 

63 

5 

5 

63 

4 

32 

17 

63 

5 

5 

64 

3 

22 

28 

1 

63 

5 

5 

65 

3 

21 

1 

1 

29 

64 

Urinary System 

Special Senses System 

Respiratory System 

Nervous System 

Musculoskeletal System 

Integumentary System 

Hematopoietic System 

Genital System 

General Body System 

Endocrine System 

Cardiovascular System 

Alimentary System 

Systems Examined At 7 Months With No Neoplasms Observed 

15-Month Interim Evaluation 

Polyp stromal 

Uterus 

Genital System 

(5) (5) 

1 (20%) 

Multiple organsb 

Systemic Lesions 

Leukemia mononuclear 
170 Nickel Sulfate Hexahydrate, NTP TR 454 

(continued) 

Summary of the Incidence of Neoplasms in Female Rats in the 2-Year Inhalation Study of Nickel Sulfate Hexahydrate 

TABLE B1 

O mg/m’ 0.12 mg/m3 0.25 mg/m3 0.5 mg/m3 

Urinary System 

Special Senses System 

Respiratory System 

Nervous System 

Musculoskeletal System 

Integumentary System 

Hematopoietic System 

General Body System 

Endocrine System 

Cardiovascular System 

Alimentary System 

Systems Examined With No Neoplasms Observed 

15-Month Interim Evaluation (continued) 

Intestine large, colon 

Alimentary System 

2- Year Study 

Carcinoma, metastatic, pancreas 

Liver 

Fibrosarcoma 

Intestine small, ileum 

Carcinoma, metastatic, pancreas 

Intestine small, jejunum 

Carcinoma, metastatic, pancreas 

Intestine small, duodenum 

Lipoma 

Intestine large, cecum 

Carcinoma, metastatic, pancreas 

Oral mucosa 

Lipoma 

Mesentery 

Pancreas 

Squamous cell papilloma 

Squamous cell carcinoma 

Stomach, forestomach 

Salivary glands 

Carcinoma 

Stomach, glandular 

Carcinoma, metastatic, pancreas 

Carcinoma, metastatic, pancreas 

(53) (54) 

(53) 

(53) 

(53) (53) (54) 

(53) 

(54) 

(3) 

3 (100%) 

(2) 

1 (50%) 

1 (50%) 

(53) 

(1) 

1 (100%) 

(53) 

(53) 

(53) 

(53) 

(53) 

(53) (53) (54) 

Heart 

Cardiovascular System 
Lesions in Female Rats 171 

(continued) 

Summary of the Incidence of Neoplasms in Female Rats in the 2-Year Inhalation Study of Nickel Sulfate Hexahydrate 

TABLE B1 

O mg/m3 0.12 mg/m3 0.25 mg/m3 0.5 mg/m3 

Adrenal medulla 

Adrenal cortex 

Endocrine System 

&Year shcdy (continued) 

Pheochromocytoma benign 

Pheochromocytoma complex 

Pituitary gland 

Parathyroid gland 

Islets, pancreatic 

Thyroid gland 

Pars distalis, adenoma 

Follicular cell, carcinoma 

Follicular cell, adenoma 

C-cell, carcinoma 

C-cell, adenoma 

3 (6%) 

(54) 

(49) 

(54) 

3 (6%) 

2 (4%) 

22 (41%) 

(52) 

1 (2%) 

1 (2%) 

Tissue NOS 

General Body System 

(6) (4) 

Pericardial, carcinoma, metastatic, pancreas 1 (17%) 

Genital System 

Bilateral, adenoma 

Carcinoma 

Adenoma 

Clitoral gland 

Granulosa-theca tumor benign 

Granulosa cell tumor benign 

Granulosa cell tumor malignant 

Schwannoma malignant 

Sarcoma stromal 

Polyp stromal 

Carcinoma, metastatic, pancreas 

Schwannorna malignant 

Fibroma 

Carcinoma, metastatic, pancreas 

Ovary 

Uterus 

Vagina 

(51) 

4 (8%) 

(53) 

1 (2%) 

1 (2%) 

1 (2%) 

(54) 

3 (6%) 3 (6%) 

1 (2%) 

1 (2%) 

7 (13%) 

(1) 

1 (2%) 

(1) (1) 

1 (100%) 

1 (100%) 

1 (100%) 

Lymph node 

Bone marrow 

Hematopoietic System 

Iliac, carcinoma, metastatic, pancreas 

Squamous cell carcinoma, metastatic, oral 

Carcinoma, metastatic, pancreas 

Pancreatic, carcinoma, metastatic, pancreas 

Lymph node, mandibular 

Lymph node, bronchial 

mucosa 

(49) 

1 (2%) 
172 Nickel Sulfate Hexahydrate, NTP TR 454 

(continued) 

Summary of the Incidence of Neoplasms in Female Rats in the 2-Year Inhalation Study of Nickel Sulfate Hexahydrate 

TABLE B1 

O mg/m3 0.12 mg/m3 0.25 mg/m3 0.5 mg/m3 

Lymph node, mediastinal 

Lymph node, mesenteric 

Hematopoietic System (continued) 

2-Year Study (continued) 

Thymus 

Spleen (52) 

(52) (53) 

(48) (50) 

Carcinoma, metastatic, pancreas 

Carcinoma, metastatic, pancreas 

1 (2%) 

1 (2%) 

(49) 

(52) 

(48) 

(53) 

Mammary gland 

Integumentary System 

Fibroadenoma, multiple 

Fibroadenoma 

Adenoma 

Adenocarcinoma 

Subcutaneous tissue, sarcoma 

Pinna, fibroma 

Squamous cell carcinoma 

Plasma cell tumor malignant 

Fibroma 

Skin 

(52) 

3 (6%) 

14 (27%) 

1 (2%) 

4 (8%) 

(53) 

1 (2%) 

1 (2%) 

(53) (53) (54) 

2 (4%) 

16 (30%) 

4 (8%) 

1 (2%) 

2 (4%) 

8 (15%) 

1 (2%) 

1 (2%) 

2 (4%) 

7 (13%) 

1 (2%) 

(53) (52) (53) 

1 (2%) 

1 (2%) 

Bone 

Musculoskeletal System 

Osteosarcoma 

(53) (53) 

Brain 

Nervous System 

(52) 

Cerebrum, astrocytoma NOS 

Astrocytoma NOS 

Lung 

Respiratory System 

(52) (53) 

Squamous cell carcinoma, metastatic, 

Alveoladbronchiolar adenoma 

uncertain primary site 

Nose (51) (52) 

(53) (54) 

1 (2%) 

Carcinoma 

Zymbal’s gland 

Retrobulbar, carcinoma 

EY e 

Special Senses System 
Lesions in Female Rats 173 

(continued) 

Summary of the Incidence of Neoplasms in Female Rats in the 2-Year Inhalation Study of Nickel Sulfate Hexahydrate 

TABLE B1 

0 mg/m’ 0.12 mg/m3 0.25 mglm’ 0.5 mglm’ 

Kidney 

Urinary System 

%Year Study (continued) 

Urinary bladder 

(52) 

(53) 

(53) 

(53) 

(53) 

Papilloma 

Carcinoma, metastatic, pancreas 1 (2%) 

(53) 

1 (2%) 

Multiple organs 

Systemic Lesions 

Lymphoma malignant 

Leukemia mononuclear 

(53) (53) (53) (54) 

25 (47%) 25 (47%) 33 (62%) 

1 (2%) 

23 (43%) 

Total animals with primary neoplasms‘ 

Neoplasm Summary 

2-Year study 

I5-Month interim evaluation 

2-Year study 

15-Month interim evaluation 

2-Year study 

15-Month interim evaluation 

2-Year study 

15-Month interim evaluation 

2-Year study 

15-Month interim evaluation 

Total primary neoplasms 

Total animals with benign neoplasms 

Total benign neoplasms 

Total animals with malignant neoplasms 

Total malignant neoplasms 

49 

1 

52 

1 

50 

2 

48 

98 

1 

91 

2 

88 

1 

83 

35 

1 

35 

1 

42 36 

52 

1 

49 

1 

59 50 

37 

1 

33 

1 

35 29 

15-Month interim evaluation 

2-Year study 

2-Year study 

2-Year study 

16 

2 

36 

Total animals with malignant neoplasms 

Total metastatic neoplasms 

Total animals with metastatic neoplasms 

of uncertain primary site 

2-Year study 

Total animals with uncertain neoplasms - 

Total uncertain neoplasms 

benign or malignant 

2-Year study 

2-Year study 

38 

1 

41 

1 

3 

1 

33 

1 

1 

1 

a Number of animals examined microscopically at the site and the number of animals with neoplasm 

Primary neoplasms: all neoplasms except metastatic neoplasms 

Number of animals with any tissue examined microscopically 
174 Nickel Sulfate Hexahydrate, NTP TR 454 

0 mg/m3 

Individual Animal Tumor Pathology of Female Rats in the 2-Year Inhalation Study of Nickel Sulfate Hexahydrate: 

TABLE B2 

~ ~ ~ 

6368264912033338369736801 

4033468822444445666788899 

4555555566666666666666666 

2073386629591484865691090 

3929332827901118991722398 

1010111010011110001011100 

~~ ~~ ~~ 

Number of Days on Study 

Carcass ID Number 

Intestine large, colon 

Esophagus 

Alimentary System 

Intestine small, duodenum 

Intestine large, cecum 

Intestine large, rectum 

Mesentery 

Liver 

Intestine small, ileum 

Intestine small, jejunum 

Salivary glands 

Pancreas 

Oral mucosa 

Tooth 

Stomach, glandular 

Stomach, forestomach 

Carcinoma, metastatic, pancreas 

Carcinoma, metastatic, pancreas 

Carcinoma, metastatic, pancreas 

Carcinoma, metastatic, pancreas 

Carcinoma 

Squamous cell carcinoma 

Carcinoma, metastatic, pancreas 

Carcinoma, metastatic, pancreas 

A+++++++A++++++++++++++++ 

A+++++++A++++++++++++++++ 

A++++++++++++++++++++++++ 

X 

A++++++++++++++++++++++++ 

.......................... 

X 

A++++++++++++++++++++++++ 

A+++++++A++++++++++++++MM 

X 

A++++++++++++++++++++++++ 

A 

X 

+ 

X 

+ 

X 

+ 

A 

A++++++++++++++++++++++++ 

A++++++++++++++++++++++++ 

x 

A++++++++++++++++++++++++ 

+ 

X 

A++++++++++++++++++++++++ 

+ 

Heart 

Cardiovascular System 

Adrenal medulla 

Adrenal cortex 

Endocrine System 

Pituitary gland 

Parathyroid gland 

Islets, pancreatic 

Thyroid gland 

......................... 

A+++++++++M++++++++++++++ 

A++++++++++++++++++++++++ 

Pheochromocytoma benign X 

A++++++++++++++++++++++++ 

M++M+M+++++++++++++++++++ 

A++++++++++++++++++++++++ 

C-cell, carcinoma 

C-cell, adenoma 

Pars distalis, adenoma 

X 

xx x xxx x x 

A++++++++++++++++++++++++ 

Tissue NOS 

General Body System 

+ + + 

Pericardial, carcinoma, metastatic, 

pancreas X 

A: Autolysis precludes examination 

+ : Tissue examined microscopically 

I: Insufficient tissue 

M: Missing tissue 

Blank: Not examined 

X: Lesion present 
Lesions in Female Rats 175 

TABLE B2 

0 mg/m3 (continued) 

Individual Animal Tumor Pathology of Female Rats in the 2-Year Inhalation Study of Nickel Sulfate Hexahydrate: 

2634179999000011111222222222 

Number of Days on Study 9911222222333333333333333333 

6677777777777777777777771777 

Carcass ID Number 

1111110111011100011001111111 Total 

2030017134802389903880022233 Tissues/ 

5048534660818922741173703457 Tumors 

Intestine large, colon 

Esophagus 

Alimentary System 

Intestine small, duodenum 

Intestine large, cecum 

Intestine large, rectum 

Mesentery 

Liver 

Intestine small, ileum 

Intestine small, jejunum 

Salivary glands 

Pancreas 

Oral mucosa 

Tooth 

Stomach, glandular 

Stomach, forestomach 

Carcinoma, metastatic, pancreas 

Carcinoma, metastatic, pancreas 

Carcinoma, metastatic, pancreas 

Carcinoma, metastatic, pancreas 

Carcinoma 

Squamous cell carcinoma 

Carcinoma, metastatic, pancreas 

Carcinoma, metastatic, pancreas 

............................ 

............................ 

............................ 

............................ 

............................ 

............................ 

............................ 

............................ 

+ 

............................ 

............................ 

............................ 

............................ 

+ 3 

1 

52 

1 

52 

52 

1 

52 

3 

3 

1 

1 

52 

49 

1 

52 

1 

51 

51 

51 

1 

52 

53 

Heart 

Cardiovascular System 

............................ 53 

Adrenal medulla 

Adrenal cortex 

Endocrine System 

Pituitary gland 

Parathyroid gland 

Islets, pancreatic 

Thyroid gland 

Pheochromocytoma benign 

C-cell, carcinoma 

C-cell, adenoma 

Pars distalis, adenoma 

............................ 

............................ 

X 

............................ 

xx 

............................ 

++++++M+++++++++++++++++++++ 

............................ 

x xx xx xxx xx x 

X 1 

1 

52 

22 

52 

49 

52 

2 

51 

52 

Tissue NOS 

General Body System 

+ 

Pericardial, carcinoma, metastatic, 

pancreas 

+ + 

1 

6 
Nickel Sulfate Hexahydrate, NTp TR 454 

0 mg/m3 (continued) 

Individual Animal Tumor Pathology of Female Rats in the 2-Year Inhalation Study of Nickel Sulfate Hexahydrate: 

TABLE B2 

6368264912033338369736801 

Number of Days on Study 4033468822444445666788899 

4555555566666666666666666 

2073386629591484865691090 

3929332827901118991722398 

1010111010011110001011100 

Carcass ID Number 

Clitoral gland 

Genital System 

Adenoma 

A++++++++M+++++++++++++++ 

xx 

Uterus 

Ovary 

X 

A++++++++++++++++++++++++ 

A++++++++++++++++++++++++ 

Carcinoma, metastatic, pancreas 

Polyp stromal 

Carcinoma, metastatic, pancreas 

Granulosa cell tumor benign 

X X X 

Vagina 

X 

+ 

Lymph node 

Bone marrow 

Hematopoietic System 

pancreas 

pancreas 

+ 

A++++++++++++++++++++++++ 

+ + + + 

Pancreatic, carcinoma, metastatic, 

Iliac, carcinoma, metastatic, 

X 

A++++++++++++++++++++++++ 

X 

M++++++++++++++++++++++++ 

X 

Lymph node, mandibular 

Lymph node, bronchial 

Squamous cell carcinoma, metastatic, 

Carcinoma, metastatic, pancreas 

oral mucosa X 

Lymph node, mesenteric 

Integumentary System 

Thymus 

Spleen 

Lymph node, mediastinal 

Fibroadenoma, multiple 

Fibroadenoma 

Adenoma 

Adenocarcinoma 

Mammary gland 

Subcutaneous tissue, sarcoma 

Squamous cell carcinoma 

A+++++++A++++++I+++++++++ 

X 

A++++++++++++++++++++++++ 

X 

A+++M++++++++++++++++++++ 

A+++++++++++++++.+++++++++ 

Carcinoma, metastatic, pancreas 

Carcinoma, metastatic, pancreas 

M++++++++++++++++++++++++ 

X X 

X 

X xx xx X X 

X 

Skin ......................... X 

X 

Brain 

Nervous System 

Bone 

Musculoskeletal System ......................... 

A++++++++++++++++++++++++ 
Lesions in Female Rats 177 

0 mg/m3 (continued) 

Individual Animal Tumor Pathology of Female Rats in the 2-Year Inhalation Study of Nickel Sulfate Hexahydrate: 

TABLE B2 

2634179999000011111222222222 

Number of Days on Study 9911222222333333333333333333 

6677777777777777777777777777 

1111110111011100011001111111 Total 

2030017134802389903880022233 Tissues/ 

5048534660818922741173703457 Tumors 

Carcass ID Number 

Genital System 

Uterus 

Ovary 

Clitoral gland 

............................ X ............................ 

1 

1 

4 

1 

52 

1 

52 

4 

51 

Carcinoma, metastatic, pancreas 

Granulosa cell tumor benign 

Adenoma 

Carcinoma, metastatic, pancreas 

Polyp stromal 

X 

X 

............................ 

X 

Vagina 

Lymph node 

Bone marrow 

Hematopoietic System 

pancreas 

pancreas 

............................ 

1 

8 

52 

+ ++ 

Pancreatic, carcinoma, metastatic, 

Iliac, carcinoma, metastatic, 

52 

1 

50 

1 

48 

52 

1 

48 

1 

52 

1 

Lymph node, mandibular 

Lymph node, bronchial ++++++++M++++++M++++++++++++ 

Squamous cell carcinoma, metastatic, 

Carcinoma, metastatic, pancreas 

............................ 

oral mucosa 

Lymph node, mesenteric 

Integumentary System 

Thymus 

Spleen 

Lymph node, mediastinal 

Fibroadenoma, multiple 

Fibroadenoma 

Adenoma 

Adenocarcinoma 

Mammary gland 

Subcutaneous tissue, sarcoma 

Squamous cell carcinoma 

++++++++++++++++++++I +I +M+++ 

............................ 

Carcinoma, metastatic, pancreas 

Carcinoma, metastatic, pancreas 

............................. 

........................... 

............................ 

3 

14 

1 

4 

52 

1 

1 

53 

X 

xx 

X X X xxx 

X X 

Skin ............................ 

Bone 

Musculoskeletal System 

............................ 53 

Brain 

Nervous System ............................ 52 
178 Nickel Sulfate Hexahydrate, NTP TR 454 

TABLE B2 

0 mg/m3 (continued) 

Individual Animal Tumor Pathology of Female Rats in the 2-Year Inhalation Study of Nickel Sulfate Hexahydrate: 

6368264912033338369736801 

4033468822444445666788899 

4555555566666666666666666 

Number of Days on Study 

Carcass ID Number 

2073386629591484865691090 

3929332827901118991722398 

1010111010011110001011100 

Trachea 

Nose 

Lung 

Laxynx 

Respiratory System 

A++++++++++++++++++++++++ 

A++++++++++++++++++++++++ 

A+++++++A++++++++++++++++ 

A++.++++++++++++++++++++++ 

Urinary bladder 

Kidney 

Urinary System 

EY e 

Special Senses System 

+ 

......................... X 

A++++++++++++++++++++++++ 

Carcinoma, metastatic, pancreas 

~~~ ______~~~ 

Multiple organs 

Systemic Lesions ~~~ 

......................... Leukemia mononuclear X xxxxxx X xxxx 
Lesions in Female Rats 179 

0 mg/m3 (continued) 

Individual Animal Tumor Pathology of Female Rats in the 2-Year Inhalation Study of Nickel Sulfate Hexahydrate: 

TABLE B2 

2634179999000011111222222222 

9911222222333333333333333333 

6677777777777777777777777777 

Number of Days on Study 

Carcass ID Number 

1111110111011100011001111111 Total 

2030017134802389903880022233 Tissues/ 

5048534660818922741113703457 Tumors 

Trachea 

Nose 

Lung 

Larynx 

Respiratory System 

............................ 

............................ 

............................ 

++++++++++++++I+++++++++++++ 

52 

51 

52 

51 

EY e 

Special Senses System 

1 

Urinary bladder 

Kidney 

Urinary System 

............................ 

53 

1 

52 

Carcinoma, metastatic, pancreas 

............................ 

Multiple organs 

Systemic Lesions 

xx xxx x X 

............................ 25 

53 

Leukemia mononuclear xxx x x X 
180 Nickel Sulfate Hexahydrate, NTP TR 454 

TABLE B2 

0.12 mg/m3 

Individual Animal Tumor Pathology of Female Rats in the 2-Year Inhalation Study of Nickel Sulfate Hexahydrate: 

2977909930266057907634443 

Number of Days on Study 9833355578999000122344445 

3455555555555666666666666 

Carcass ID Number 

2379691869048178046971230 

7555773653267644771211678 

2222222222222222222222222 

Intestine large, cecum 

Intestine large, rectum 

Intestine large, colon 

Esophagus 

Alimentary System 

Intestine small, ileum 

Intestine small, jejunum 

Intestine small, duodenum 

Oral mucosa 

Mesentery 

Liver 

Fibrosarcoma 

Lipoma 

Squamous cell papilloma 

Squamous cell carcinoma 

Tooth 

Tongue 

Stomach, glandular 

Stomach, forestomach 

Salivary glands 

Pancreas 

......................... 

......................... 

++++++++++A+++++++++++++A 

......................... 

++++++++++A+++++++++++++A 

......................... 

......................... 

......................... ++ 

X 

+ 

......................... 

......................... 

......................... 

......................... 

+ 

+ + + 

Heart 

Cardiovascular System 

......................... 

Adrenal medulla 

Adrenal cortex 

Endocrine System 

Pituitary gland 

Parathyroid gland 

Islets, pancreatic 

Thyroid gland 

Pheochromocytoma benign 

Pars distalis, adenoma 

Follicular cell, carcinoma 

Follicular cell, adenoma 

C-cell, adenoma 

......................... 

......................... 

X 

......................... 

+++++++++++++I+++++++++++ 

......................... 

X 

......................... X xx X X X X xx 

X 

Tissue NOS 

General Body System 

+ ++ 

Carcinoma 

Adenoma 

Clitoral gland 

Genital System 

Schwannoma malignant 

Polyp stromal 

Granulosa cell tumor malignant 

......................... 

......................... X 

++++++++++++M++++++++++++ 

X 

Uterus 

Ovary 
Lesions in Female Rats 181 

TABLE B2 

0.12 mg/m3 (continued) 

Individual Animal Tumor Pathology of Female Rats in the 2-Year Inhalation Study of Nickel Sulfate Hexahydrate: 

6784468216599999990000111222 

5556617890222222223333333333 

6666666667777777777777771777 

2222222222222222222222222222 Total 

2344521664312244563571236123 Tissues1 

1503123931653829458057637870 Tumors 

Number of Days on Study 

Carcass ID Number 

Intestine large, cecum 

Intestine large, rectum 

Intestine large, colon 

Esophagus 

Alimentary System 

Intestine small, ileum 

Intestine small, jejunum 

Intestine small, duodenum 

Oral mucosa 

Mesentery 

Liver 

Fibrosarcoma 

Lipoma 

Squamous cell papilloma 

Squamous cell carcinoma 

Tooth 

Tongue 

Stomach, glandular 

Stomach, forestomach 

Salivary glands 

Pancreas 

............................ 

+++++++++++++I ++++I +++++++++ 

+++++++++++++M++++++++++++++ 

............................ 

53 

51 

50 

53 

53 

X 1 

............................ 

............................ 

............................ 

X ............................ 

+ 

X 

............................ 

............................ 53 53 

1 

1 

2 

2 

53 

1 

51 

53 

............................ 

............................ 

5 

1 

53 

53 

+ + 

Heart 

Cardiovascular System 

............................ 53 

Adrenal medulla 

Adrenal cortex 

Endocrine System 

Pituitary gland 

Parathyroid gland 

Islets, pancreatic 

Thyroid gland 

Pheochromocytoma benign 

Pars distalis, adenoma 

Follicular cell, carcinoma 

Follicular cell, adenoma 

C-cell, adenoma 

............................ 

X 

............................ 

............................ 

............................ 

xx 

............................ 

............................ 

X 

x xxxx xx x xx xxx X 

X 

X 

53 

24 

53 

52 

53 

4 

53 

53 

1 

1 

2 

Tissue NOS 

General Body System 

Carcinoma 

Adenoma 

Clitoral gland 

Genital System 

Schwannoma malignant 

Polyp stromal 

Granulosa cell tumor malignant 

+ 4 

............................ 

1 

4 

52 

1 

3 

53 

1 

53 

X xx 

uterus 

Ovary 

............................ X ............................ 

X X X 

X 
Nickel Sulfate Hexahydrate, NTP TR 454 

2977909930266051907634443 

9833355578999000122344445 

3455555555555666666666666 

2379691869048178046971230 

7555773653267644771211678 

2222222222222222222222222 

Number of Days on Study 

Carcass ID Number 

Bone marrow 

Hematopoietic System 

Schwannoma malignant 

Vagina 

Genital System (continued) 

X 

+ 

......................... 

Lymph node, mediastinal 

Lymph node, mesenteric 

Lymph node, mandibular 

Lymph node, bronchial 

Lymph node + + + 

++++++++++++++++++++M++++ 

......................... 

......................... 

+++++++++++++++M+++++++++ 

+ 

Thymus 

Spleen 

+++M+++++++++I+++++++++++ 

......................... 

Mammary gland 

Integumentary System 

Fibroadenoma, multiple 

Fibroadenoma 

Adenocarcinoma 

Skin 

xxxxx xx X X 

......................... 

xx ., A 

......................... Plasma cell tumor malignant X 

Bone 

Musculoskeletal System 

~~ ~ 

......................... 

Brain 

Nervous System 

~~ ~ ~~ 

......................... Cerebrum, astrocytoma NOS 

~ 

Trachea 

Nose 

Lung 

Larynx 

Respiratory System 

......................... 

......................... 

......................... 

......................... 

Retrobulbar, carcinoma 

EY e 

Special Senses System 

+ 

Urinary bladder 

Kidney 

Urinary System 

Papilloma 

......................... 

......................... 

Multiple organs 

Systemic Lesions 

Leukemia mononuclear x xxxx xx x ......................... x xx xx 
Lesions in Female Rats 183 

TABLE B2 

0.12 mg/m3 (continued) 

Individual Animal Tumor Pathology of Female Rats in the 2-Year Inhalation Study of Nickel Sulfate Hexahydrate: 

6784468216599999990000111222 

5556677890222222223333333333 

6666666667777777777777777777 

Number of Days on Study 

Carcass ID Number 

2222222222222222222222222222 Total 

2344521664312244563577236123 Tissues/ 

1503123931653829458057637870 Tumors 

Schwannoma malignant 

Vagina 

Genital System (continued) 

1 

1 

Thymus 

Spleen 

Lymph node, mediastinal 

Lymph node, mesenteric 

Lymph node, mandibular 

Lymph node, bronchial 

Lymph node 

Bone marrow 

Hematopoietic System 

............................ + + + 

++A+++++++++++++++++++++++++ 

+++M+++++++I++++++++++++++++ 

............................ 

+++++++M++++++++++++++++++++ 

............................ 

++A+++++++++M+++++++++++++++ 49 

52 

50 

53 

52 

52 

7 

53 

Mammary gland 

Integumentary System 

X 

............................ 

1 

53 

2 

16 

4 

53 

Fibroadenoma, multiple 

Fibroadenoma 

Adenocarcinoma 

Plasma cell tumor malignant 

xx x X 

xx X 

X 

Skin ............................ 

Bone 

Musculoskeletal System ............................ 53 

Brain 

Nervous System 

............................ 1 

53 

Cerebrum, astrocytoma NOS X 

Trachea 

Nose 

Lung 

Larynx 

Respiratory System 

............................ 

++A+++++++++++++++++++++++++ 

............................ 

............................ 

53 

52 

53 

53 

Retrobulbar, carcinoma 

EY e 

Special Senses System 

+ 

X 

+ t 

1 

4 

Urinary bladder 

Kidney 

Urinary System 

Papilloma 

............................ 

............................ 

1 

53 

53 

X 

Multiple organs 

Systemic Lesions 

xx 

............................ 25 

53 

Leukemia mononuclear xxx X xx xxxx 
184 Nickel Sulfate Hexahydrate, NTP TR 454 

0.25 mglm’ 

Individual Animal Tumor Pathology of Female Rats in the 2-Year Inhalation Study of Nickel Sulfate Hexahydrate: 

TABLE B2 

305879927885122255370601 

010012244445666677890011 

456666666666666666667777 

Number of Days on Study 

Carcass ID Number 

601406394807991718660244 

505766955797768868817568 

343333333333333333343333 

Mesentery 

Liver 

Intestine small, ileum 

Intestine small, jejunum 

Intestine small, duodenum 

Intestine large, cecum 

Intestine large, rectum 

Intestine large, colon 

Esophagus 

Alimentary System 

Oral mucosa 

Lipoma 

Stomach, glandular 

Stomach, forestomach 

Salivary glands 

Pancreas 

Squamous cell carcinoma 

........................ 

M+++++++++++++++++++++++ 

........................ 

M+++++++++++++++++++++++ 

........................ 

M+++++++++++++++++I+++++ 

........................ 

........................ 

+ 

+ + 

X X 

........................ 

........................ 

........................ 

........................ 

Heart 

Cardiovascular System 

......................... 

Adrenal medulla 

Adrenal cortex 

Endocrine System 

Pheochromocytoma benign 

Pheochromocytoma complex 

Pituitary gland 

Parathyroid gland 

Islets, pancreatic 

Thyroid gland 

C-cell, carcinoma 

C-cell, adenoma 

Pars distalis, adenoma 

........................ 

........................ 

........................ 

++++++++++++++++++M+++++ 

........................ X 

X 

........................ x x x xxx xxx 

X 

X 

xx 

Tissue NOS 

General Body System 

Adenoma 

Clitoral gland 

Genital System 

Vagina 

uterus 

Ovary 

~~ 

........................ 

........................ 

+++++++++++++++++++M++++ 

X 

Fibroma 

Polyp stromal X 
Lesions in Female Rats 185 

0.25 mgh’ (continued) 

Individual Animal Tumor Pathology of Female Rats in the 2-Year Inhalation Study of Nickel Sulfate Hexahydrate: 

TABLE B2 

~~ ~~~ ~ ~~ ~ 

59999900000011111111112222222 

12222233333333333333333333333 

77777777777777777777777777777 

33333433344433333444443334444 Total 

87799167901156699000117880112 Tissues/ 

51367582964782545178125232380 Tumors 

~~ ~~~ ~~~ ~ 

Number of Days on Study 

Carcass ID Number 

Esophagus 

Alimentary System 

............................. 53 

Mesentery 

Liver 

Intestine small, ileum 

Intestine small, jejunum 

Intestine small, duodenum 

Intestine large, cecum 

Intestine large, rectum 

Intestine large, colon 

Oral mucosa 

Lipoma 

Stomach, glandular 

Stomach, forestomach 

Salivary glands 

Pancreas 

Squamous cell carcinoma 

............................. 53 

++++++++++I ++++++++++I +++++++ 49 

............................. 53 

............................. 52 

............................. 53 

............................. 52 

............................. 53 

X 

+ 

............................. 

............................. 

............................. 

............................. 

53 

53 

53 

53 

2 

2 

1 

2 

Heart 

Cardiovascular System 

~~ ~~~ ~ ~~ ~ 

............................. 53 

~~ ~ ~~ ~ ~~ ~~~~ ~ 

Adrenal medulla 

Adrenal cortex 

Endocrine System 

~~ 

++++++++++++++++++M++++++++++ 51 

............................. 53 

2 

1 

............................. 53 

............................. 53 

Pheochromocytoma benign 

Pheochromocytoma complex 

X 

Parathyroid gland 

Islets, pancreatic 

Thyroid gland 

Pituitary gland 

C-cell, carcinoma 

C-cell, adenoma 

Pars distalis, adenoma 

2 

4 

............................. 53 

24 

............................. 53 

xxx xxx x x xx x xxx 

X 

xx 

Tissue NOS 

General Body System 

Adenoma 

Clitoral gland 

Genital System 

Ovary 

+ + 2 

............................. 53 

3 

............................. 52 

X X 

Vagina 

uterus 

Fibroma 

Polyp stromal 

1 

1 

3 

............................. 53 

X X 

X 

+ 
186 Nickel Sulfate Hexahydrate, NTP TR 454 

0.25 mg/m3 (continued) 

Individual Animal Tumor Pathology of Female Rats in the 2-Year Inhalation Study of Nickel Sulfate Hexahydrate: 

TABLE B2 

305879921885122255310601 

010012244445666677890011 

456666666666666666667777 

Number of Days on Study 

Carcass ID Number 

601406394807991718660244 

505766955797768868817568 

343333333333333333343333 

Thymus 

Spleen 

Lymph node, mediastinal 

Lymph node, mesenteric 

Lymph node, mandibular 

Lymph node, bronchial 

Lymph node 

Bone marrow 

Hematopoietic System 

++++++++++++I+++++++++++ 

........................ 

M++++++++++++++++++M++++ 

........................ 

........................ 

........................ 

++ + + + + + +++ ........................ 

Mammary gland 

Integumentary System 

Fibroadenoma, multiple 

Fibroadenoma 

Adenocarcinoma 

Fibroma 

Skin 

........................ X 

X X 

X X 

......................... 

Bone 

Musculoskeletal System 

Osteosarcoma 

........................ X 

Brain 

Nervous System 

........................ Astrocytoma NOS 

Lung 

Larynx 

Respiratory System 

X 

........................ 

........................ 

Squamous cell carcinoma, metastatic, 

uncertain primary site 

Trachea 

Nose 

........................ 

........................ 

Zymbal’s gland 

EY e 

Special Senses System 

Carcinoma 

Urinary bladder 

Kidney 

Urinary System 

Multiple organs 

Systemic Lesions 

X 

+ 

+ 

........................ 

........................ 

xxxx xx xxxx xxxxxxxxxx 

........................ Leukemia mononuclear 
Lesions in Female Rats 187 

0.25 mg/m3 (continued) 

Individual Animal Tumor Pathology of Female Rats in the 2-Year Inhalation Study of Nickel Sulfate Hexahydrate: 

TABLE B2 

~ 

59999900000~011111111112222222 

12222233333333333333333333333 

77777777777777777777777777777 

33333433344433333444443334444 Total 

87799167901156699000117880112 Tissues/ 

51367582964782545178125232380 Tumors 

~_____ ~________ 

Number of Days on Study 

Carcass ID Number 

Thymus 

Spleen 

Lymph node, mediastinal 

Lymph node, mesenteric 

Lymph node, mandibular 

Lymph node, bronchial 

Lymph node 

Bone marrow 

Hematopoietic System 

++++++++++M++++++++++++++++++ 51 

............................. 53 

+I +MI ++M+++MM+++I ++++++++++++ 44 

............................. 53 

++++M++++++++++++++++++++++++ 52 

+++++++++++++M++M++++++++++++ 51 

11 

............................. 53 

+ 

Mammary gland 

Integumentary System 

1 

+++++++++++++++M+++++++++++++ 52 

2 

xx 8 

1 

............................. 53 

Fibroadenoma, multiple 

Fibroadenoma 

Adenocarcinoma 

Fibroma 

X X X X 

Skin 

X 

Bone 

Musculoskeletal System 

1 

............................. 53 

Brain 

Nervous System 

Osteosarcoma 

............................. 1 53 

Astrocytoma NOS 

Lung 

Larynx 

Respiratory System 

++++++++++++++++++M++++++++++ 52 

............................. 53 

Squamous cell carcinoma, metastatic, 

uncertain primary site X 

............................. 53 

............................. 53 

1 

Trachea 

Nose 

Zymbal’s gland 

EY e 

Special Senses System 

Carcinoma 1 

1 

1 

Urinary bladder 

Kidney 

Urinary System 

............................. 53 

............................. 53 

Multiple organs 

Systemic Lesions 

............................. 53 

Leukemia mononuclear x xx X xx x xxx xx x 33 
188 Nickel Sulfate Hexahydrate, NTP TR 454 

TABLE B2 

0.5 mg/m3 

Individual Animal Tumor Pathology of Female Rats in the 2-Year Inhalation Study of Nickel Sulfate Hexahydrate: 

892302507788818784121587 

Number of Days on Study 217273789233346345668889 

012334444555555666666666 

479732209465094517434350 

429959004301205094941094 

554454555555555545455545 

Carcass ID Number 

Intestine large, colon 

Esophagus 

Alimentary System 

........................ 

........................ 

Mesentery 

Liver 

Intestine small, ileum 

Intestine small, jejunum 

Intestine small, duodenum 

Intestine large, cecum 

Intestine large, rectum 

, Oral mucosa 

Squamous cell carcinoma 

. Pancreas 

Tooth 

Stomach, glandular 

Stomach, forestomach 

Salivary glands 

......................... 

........................ 

........................ 

+++++++++++++A++++++++++ 

+++++++++++++A++++++++++ 

+++++I I +++++++++I +++++++ 

+ 

X 

+ 

........................ 

++++++++++++++++++M+++++ 

........................ 

........................ 

Heart 

Cardiovascular System 

........................ Lymphoma malignant, metastatic, 

thymus X 

Adrenal medulla 

Adrenal cortex 

Endocrine System 

Pituitary gland 

Parathyroid gland 

Islets, pancreatic 

Thyroid gland 

Pheochromocytoma benign 

C-cell, carcinoma 

C-cell, adenoma 

Pars distalis, adenoma 

........................ 

........................ 

........................ 

MM+++++++++++++++++++MM+ 

........................ 

....................... 

X X xx X 

X 

Tissue NOS 

General Body System 

Carcinoma 

Adenoma 

Clitoral gland 

Genital System 

Granulosa-theca tumor benign 

Granulosa cell tumor malignant 

Bilateral, adenoma 

Schwannoma malignant 

Sarcoma stromal 

Polyp stromal 

+ ++ 

........................ 

Ovary ........................ 

X 

uterus 

X 

........................ xx X 
Lesions in Female Rats 189 

0.5 mg/m3 (continued) 

Individual Animal Tumor Pathology of Female Rats in the 2-Year Inhalation Study of Nickel Sulfate Hexahydrate: 

TABLE B2 

299999990000000000111111222222 

Number of Days on Study 022222223333333333333333333333 

111111111111111111111111111111 

599201564674680388118268823592Tumors 

212455550112223335011334912335Tissuesl 

555555555555555555555555455555 Total 

Carcass ID Number 

Oral mucosa 

Mesentery 

Liver 

Intestine small, ileum 

Intestine small, jejunum 

Intestine small, duodenum 

Intestine large, cecum 

Intestine large, rectum 

Intestine large, colon 

Esophagus 

Alimentary System 

Tooth 

Stomach, glandular 

Stomach, forestomach 

Salivary glands 

Pancreas 

Squamous cell carcinoma 

.............................. 54 

.............................. 54 

+++++++++++I I +++I ++++I I ++++++I 45 

.............................. 53 

.............................. 53 

.............................. 54 

.............................. 53 

.............................. 54 

1 

1 

1 

.............................. 54 

.............................. 54 

.............................. 53 

.............................. 54 

+ 1 

Heart 

Cardiovascular System 

1 

.............................. 54 

Lymphoma malignant, metastatic, 

thymus 

Adrenal medulla 

Adrenal cortex 

Endocrine System 

Pituitary gland 

Parathyroid gland 

Islets, pancreatic 

Thyroid gland 

Pheochromocytoma benign 

C-cell, carcinoma 

C-cell, adenoma 

Pars distalis, adenoma 

.............................. 

.............................. 

X x X 

.............................. 

x xx x xxx .............................. 

++++++++++++++++M+++++++++++++ 

.............................. 

X xx xxxxxxx 

X X 

xx 

52 

22 

54 

49 

54 

3 

54 

54 

3 

2 

Tissue NOS 

General Body System 

Carcinoma 

Adenoma 

Clitoral gland 

Genital System 

Polyp stromal 

Granulosa-theca tumor benign 

Granulosa cell tumor malignant 

Bilateral, adenoma 

+ + 5 

X 1 

.............................. 54 

1 

1 

.............................. 54 

1 

X 1 

2 

.............................. 54 

X X 

X 

Ovary 

X 

Uterus 

X X X 

Schwannoma malignant 

Sarcoma stromal 

X 1 

1 
190 Nickel Sulfate Hexahydrate, NTP TR 454 

TABLE B2 

OS mg/m3 (continued) 

Individual Animal Tumor Pathology of Female Rats in the 2-Year Inhalation Study of Nickel Sulfate Hexahydrate: 

892302507788818784121587 

217273789233346345668889 

012334444555555666666666 

479732209465094517434350 

429959004301205094941094 

554454555555555545455545 

Number of Days on Study 

Carcass ID Number 

Lymph node, bronchial 

Lymph node 

Bone marrow 

Hematopoietic System 

+++IM+++++++++++++++++++ 

........................ + ++ 

Lymphoma malignant, metastatic, 

thymus X 

Thymus 

Spleen 

Lymph node, mediastinal 

Lymph node, mesenteric 

Lymph node, mandibular 

++++I +I +++++++++++++++++ ........................ 

++M+M+++++++++++++++++++ 

........................ 

++M++++++++I++++++++++++ 

Mammary gland 

Integumentary System 

Fibroadenoma, multiple 

Fibroadenoma 

Adenocarcinoma 

Pinna, fibroma 

Fibroma 

Skin 

........................ 

xx 

........................ X 

Skeletal muscle 

Bone 

Musculoskeletal System 

........................ + 

Spinal cord 

Brain 

Nervous System 

Lung 

Larynx 

Respiratory System 

........................ + 

........................ 

+++++++++++++A++++++++++ 

Alveolar/bronchiolar adenoma 

Lymphoma malignant, metastatic, 

thymus X 

Trachea 

Nose 

........................ 

........................ 

EY e 

Ear 

Special Senses System 

+ ++ 

+ 

+ ~ ~ 

Urinary bladder 

Kidney 

Urinary System 

Multiple organs 

Systemic Lesions 

~~~~~~~ _____ 

........................ 

........................ 

xxxx xxxx ........................ 

Lymphoma malignant 

Leukemia mononuclear x xx 

X 
Lesions in Female Rats 191 

0.5 mg/m3 (continued) 

Individual Animal Tumor Pathology of Female Rats in the 2-Year Inhalation Study of Nickel Sulfate Hexahydrate: 

TABLE B2 

299999990000~000000111111222222 

022222223333333333333333333333 

777777777777771777777777~77777 

Number of Days on Study 

~ 

Carcass ID Number 

~~ ~ ~~ 

599201564674680388718268823592Tumors 

212455550112223335011334912335Tissues/ 

555555555555555555555555455555 Total 

Lymph node, bronchial 

Lymph node 

Bone marrow 

Hematopoietic System 

Lymphoma malignant, metastatic, 

thymus 

Thymus 

Spleen 

Lymph node, mediastinal 

Lymph node, mesenteric 

Lymph node, mandibular 

++++++++++M+I+++++++++++M+++++ 49 

3 

.............................. 54 

.............................. 52 

.............................. 54 

++++++++++++++M++M++++++++++++ 50 

.............................. 54 

+++++++++++++++++++++I++M+++++ 50 

1 

Mammary gland 

Integumentary System 

Fibroadenoma, multiple 

Fibroadenoma 

Adenocarcinoma 

Pinna, fibroma 

Fibroma 

Skin 

X 1 

1 

+++++++++++++++++++++M++++++++ 53 

2 

xx 7 

1 

.............................. 54 

X 

xx X 

X X 

Skeletal muscle 

Bone 

Musculoskeletal System 

1 

.............................. 54 

Spinal cord 

Brain 

Nervous System 

1 

.............................. 54 

Lung 

Lalynx 

Respiratory System 

1 

.............................. 54 

.............................. 53 

Lymphoma malignant, metastatic, 

Alveolarlbronchiolar adenoma X 

thymus 

.............................. 54 

.............................. 54 

1 

Trachea 

Nose 

EY e 

Ear 

Special Senses System 

Urinary bladder 

Kidney 

Urinary System 

6 

1 

+ + 

.............................. 54 

.............................. 54 

Multiple organs 

Systemic Lesions 

Lymphoma malignant 

Leukemia mononuclear 

1 

xx X X 23 

.............................. 54 

x x x xx xx 
192 Nickel Sulfate Hexahydrate, NTP TR 454 

Statistical Analysis of Primary Neoplasms in Female Rats in the 2-Year Inhalation Study of Nickel Sulfate Hexahydrate 

TABLE B3 

0 mglm' 0.12 mg/m3 0.25 mg/m3 0.5 mg/mJ 

Fisher exact tes 

Cochran-AMta e testd 

Logistic regression testd 

Life table testd 

First incidence (days) 

Terminal rate' 

Adjusted rateb 

Overall ratea 

Adrenal Medulla: Benign Pheochromocytoma 

Fisher exact test 

Cochran-Armitage test 

Logistic regression test 

Life table test 

First incidence (days) 

Terminal rate 

Adjusted rate 

Overall rate 

Adrenal Medulla: Benign or Complex Pheochromocytoma 

Fisher exact test 

Cochran-Armitage test 

Logistic regression test 

Life table test 

First incidence (days) 

Terminal rate 

Adjusted rate 

Overall rate 

Clitoral Gland: Adenoma 

Fisher exact test 

Cochran-Armitage test 

Logistic regression test 

Life table test 

First incidence (days) 

Terminal rate 

Adjusted rate 

Overall rate 

Clitoral Gland: Adenoma or Carcinoma 

Fisher exact test 

Cochran-Armitage test 

Logistic regression test 

Life table test 

First incidence (days) 

Terminal rate 

Adjusted rate 

Overall rate 

Mammary Gland: Fibroadenoma 

6.6% 

2/51 (4%) 

P=O.550 

P=O.528 

P=0.516N 

584 

1 /22 (5 %) 

t! 

P=O.529 

P=O.506 

P=0.524N 

584 

1/22 (5 %) 

6.6% 

2/51 (4%) 

P=0.360N 

P=0.359N 

P=0.242N 

683 

1/22 (5%) 

13.9% 

4/51 (8%) 

13.9% 

4/5 1 (8 %) 

P=0.464N 

P=0.472N 

P=0.327N 

683 

1/22 (5%) 

P=0.016N 

P=0.014N 

P=O.OlON 

542 

7/22 (32%) 

49.0% 

17/53 (32%) 

P=O.349 

P=O.238 

644 

1/17 (6%) 

15.5% 

4/53 (8%) 

PzO.358 

P=O.349 

P=O.238 

644 

1/17 (6%) 

15.5% 

4/53 (8%) 

P=O.358 

P=O.539 

P=O.471 

596 

3/17 (18%) 

19.7% 

4/52 (8 %) 

P-0.631N 

P=O.403 

P=O.323 

596 

3/17 (18%) 

22.4% 

5/52 (10%) 

P=O.512 

P=0.527N 

P=O.262 

392 

1/17 (6%) 

44.1 % 

18/53 (34%) 

P=O.500 

P=0.679N 

P=0.628N 

71 1 

1/28 (4%) 

6.8% 

2/53 (4%) 

P=0.676N 

P=O.523 

P=O.584 

700 

1/28 (4%) 

9.6% 

3/53 (6%) 

P=O.518 

P=0.465N 

P=0.413N 

647 

2/28 (7%) 

9.2% 

3/52 (6%) 

P=0.489N 

P=0.465N 

P=0.413N 

647 

2/28 (7%) 

9.2% 

3/52 (6%) 

P=0.489N 

P=0.080N 

P=0.045N 

617 

6/28 (21 %) 

28.8% 

10153 (19%) 

P=0.090N 

P=O.484 

P=O.583 

729 (T) 

3/29 (10%) 

10.3% 

3/54 (6%) 

P=O.527 

P=O.484 

P=O.583 

729 (T) 

3/29 (10%) 

10.3% 

3/54 (6%) 

P=O.527 

P=0.500N 

P=0.405N 

729 (T) 

3/29 (10%) 

10.3% 

3/54 (6%) 

P=0.468N 

P=0.640N 

P=0.535N 

729 (T) 

4/29 (14%) 

13.8% 

4/54 (7%) 

P=0.610N 

P=0.074N 

P=0.036N 

538 

6/29 (21 %) 

26.8% 

9/54 (17%) 

P=0.051N 
Lesions in Female Rats 193 

(continued) 

Statistical Analysis of Primary Neoplasms in Female Rats in the 2-Year Inhalation Study of Nickel Sulfate Hexahydrate 

TABLE B3 

O mg/m3 0.12 mg/m3 0.25 mg/m3 0.5 mg/m3 

Fisher exact test 

Cochran-Armitage test 

Logistic regression test 

Life table test 

First incidence (days) 

Terminal rate 

Adjusted rate 

Overall rate 

Mammary Gland: Fibroadenoma or Adenoma 

Fisher exact test 

Cochran-Amitage test 

Logistic regression test 

Life table test 

First incidence (days) 

Terminal rate 

Adjusted rate 

Overall rate 

Mammary Gland: Carcinoma 

Fisher exact test 

Cochran-Armitage test 

Logistic regression test 

Life table test 

First incidence (days) 

Terminal rate 

Adjusted rate 

Overall rate 

Mammary Gland: Adenoma or Carcinoma 

Fisher exact test 

Cochran-Armitage test 

Logistic regression test 

Life table test 

First incidence (days) 

Terminal rate 

Adjusted rate 

Overall rate 

Mammary Gland: Fibroadenoma, Adenoma, or Carcinoma 

Fisher exact test 

Cochran-Armitage test 

Logistic regression test 

Life table test 

First incidence (days) 

Terminal rate 

Adjusted rate 

Overall rate 

Oral Mucosa: Squamous Cell Carcinoma 

P=O.OlON 

P=0.009N 

P=0.007N 

542 

7/22 (32%) 

50.5% 

18/53 (34%) 

P=0.073N 

P=0.066N 

P=0.044N 

643 

2/22 (9%) 

13.9% 

4/53 (8%) 

P=O.O4ON 

P=0.037N 

P=0.023N 

643 

2/22 (9%) 

16.3% 

5/53 (9%) 

P=0.002N 

P=0.002N 

P=0.001N 

542 

9/22 (41 %) 

59.4% 

22/53 (42%) 

P=0.277N 

P=0.159N 

P=0.298N 

536 

0/22 (0%) 

6.4% 

3/53 (6%) 

P=0.442N 

P=O.311 

392 

1/17 (6%) 

44.1 % 

18/53 (34%) 

P=0.581N 

P=O.501 

P=O.482 

706 

2/17 (12%) 

21.1% 

4/53 (8%) 

P=0.642N 

P=0.639N 

P=O.589 

706 

2/17 (12%) 

21.1% 

4/53 (8%) 

P=0.500N 

P=0.419N 

P=O.322 

392 

3/17 (18%) 

53.7 x 

21/53 (40.%) 

P=0.500N 

P=0.197N 

P=0.338N 

559 

0/17 (0%) 

2.1% 

1/53 (2%) 

P=0.309N 

P=0.055N 

P=0.031N 

617 

6/28 (21 %) 

28.8% 

10153 (19%) 

P=0.061N 

P=0.173N 

P=0.147N 

662 

0128 (0%) 

2.5% 

1/53 (2%) 

P=0.181N 

P=O.lOlN 

P=0.085N 

662 

0128 (0%) 

2.5% 

1/53 (2%) 

P=0.103N 

P=0.015N 

P=0.009N 

617 

6/28 (21 46) 

30.7% 

11/53 (21 %) 

P=0.018N 

P=0.568N 

P=0.468N 

661 

0128 (0%) 

5.1% 

2/53 (4%) 

P=0.500N 

P=0.050N 

P=0.025N 

538 

6/29 (21 %) 

26.8% 

9/54 (17%) 

P=0.033N 

P=O. 194N 

P=0.141N 

729 (T) 

1/29 (3%) 

3.4% 

1/54 (2%) 

P=0.176N 

P=0.116N 

P=O.O84N 

729 (T) 

1/29 (3 %) 

3.4% 

1/54 (2%) 

P=0.098N 

P=0.015N 

P=0.006N 

538 

7/29 (24 X) 

30.0% 

10154 (19%) 

P=0.008N 

P=0.178N 

P=0.355N 

480 

0129 (0%) 

2.1 % 

1/54 (2%) 

P=0.302N 
194 Nickel Sulfate Hexahydrate, NTP TR 454 

(continued) 

Statistical Analysis of Primary Neoplasms in Female Rats in the 2-Year Inhalation Study of Nickel Sulfate Hexahydrate 

TABLE B3 

O mg/m3 0.12 mg/m3 0.25 mg/m3 0.5 mg/rn3 

Fisher exact test 

Cochran-Armitage test 

Logistic regression test 

Life table test 

First incidence (days) 

Terminal rate 

Adjusted rate 

Overall rate 

Oral Mucosa: Squamous Cell Papilloma or Squamous Cell Carcinoma 

Fisher exact test 

Cochran-Armitage test 

Logistic regression test 

Life table test 

First incidence (days) 

Terminal rate 

Adjusted rate 

Overall rate 

Pituitary Gland (Pars Distalis): Adenoma 

Fisher exact test 

Cochran-Armitage test 

Logistic regression test 

Life table test 

First incidence (days) 

Terminal rate 

Adjusted rate 

Overall rate 

Thyroid Gland (C-cell): Adenoma 

Fisher exact test 

Cochran-Armitage test 

Logistic regression test 

Life table test 

First incidence (days) 

Terminal rate 

Adjusted rate 

Overall rate 

Thyroid Gland (C-cell): Carcinoma 

Fisher exact test 

Cochran-Armitage test 

Logistic regression test 

Life table test 

First incidence (days) 

Terminal rate 

Adjusted rate 

Overall rate 

Thyroid Gland (C-cell): Adenoma or Carcinoma 

P=0.228N 

P=0.145N 

P=0.232N 

536 

0/22 (0%) 

6.4% 

3/53 (6%) 

P=0.434N 

P=O.536 

P=0.142N 

62 1 

11/22 (50%) 

63.6% 

22/52 (42%) 

P=O.384 

P=O.376 

P=O.476 

62 1 

0122 (0%) 

2.2% 

1/52 (2 %) 

P=O.lOO 

P=O.127 

P=O.176 

729 (T) 

1/22 (5 %) 

4.5% 

1/52 (2%) 

P=O.107 

P=O. 106 

P=O.206 

62 1 

1/22 (5%) 

6.7% 

2/52 (4%) 

P=0.404N 

P=0.552N 

559 

1/17 (6%) 

7.9% 

2/53 (4%) 

P=0.500N 

P=O.268 

P=O. 118 

537 

9/17 (53%) 

72.3% 

24/53 (45 %) 

P=O.456 

P10.526 

P=O.419 

619 

1/17 (6%) 

8.4% 

2/53 (4%) 

P20.507 

0117 (0%) 

0.0% 

0153 (0%) 

P=0.495N 

P=0.551N 

P=0.551N 

- 

e 

P=O.686 

P-0.604 

619 

1/17 (6%) 

8.4% 

2/53 (4%) 

P-0.684N 

P=0.568N 

P=0.468N 

66 1 

0/28 (0%) 

5.1% 

2/53 (4%) 

P=0.500N 

P=O.549 

P=0.430N 

629 

14/28 (50%) 

62.1 % 

24/53 (45%) 

P=O.456 

P=O.174 

P=O.224 

648 

1/28 (4%) 

10.6% 

4/53 (8%) 

P=O.187 

P=O.585 

P=O.585 

729 (T) 

2/28 (7%) 

7.1% 

2/53 (4%) 

P=O.507 

P=O. 145 

P=O.200 

648 

3/28 (11%) 

17.3% 

6/53 (1 1 X) 

P=O.141 

P=0.178N 

P=0.355N 

480 

0/29 (0%) 

2.1 % 

1/54 (2%) 

P=0.302N 

P=O.463 

P=0.321N 

538 

16/29 (55%) 

62.3% 

22/54 (41 %) 

P=0.513N 

P=O.482 

P=O.547 

729 (T) 

2/29 (7%) 

6.9% 

2/52 (4%) 

P=O.500 

P=O.297 

P=O.379 

66 1 

2/29 (7%) 

9.5% 

3/52 (6%) 

P=O.309 

P=O.197 

P=O.292 

66 1 

4/29 (14%) 

16.2% 

5/52 (10%) 

P=O.218 
Lesions in Female Rats 195 

TABLE B3 

(continued) 

Statistical Analysis of Primary Neoplasms in Female Rats in the 2-Year Inhalation Study of Nickel Sulfate Hexahydrate 

O mg/m3 0.12 mg/m3 0.25 mg/m3 0.5 mg/m3 

Fisher exact test 

Cochran-Armitage test 

Logistic regression test 

Life table test 

First incidence (days) 

Terminal rate 

Adjusted rate 

Overall rate 

Uterus: Stromal Polyp 

Fisher exact test 

Cochran-Armitage test 

Logistic regression test 

Life table test 

First incidence (days) 

Terminal rate 

Adjusted rate 

Overall rate 

Uterus: Stromal Polyp or Stromal Sarcoma 

Fisher exact test 

Cochran-Armitage test 

Logistic regression test 

Life table test 

First incidence (days) 

Terminal rate 

Adjusted rate 

Overall rate 

All Organs: Mononuclear Cell Leukemia 

Fisher exact test 

Cochran-Armitage test 

Logistic regression test 

Life table test 

First incidence (days) 

Terminal rate 

Adjusted rate 

Overall rate 

All Organs: Benign Neoplasms 

Fisher exact test 

Cochran-Armitage test 

Logistic regression test 

Life table test 

First incidence (days) 

Terminal rate 

Adjusted rate 

Overall rate 

All Organs: Malignant Neoplasms 

P=O.149 

P=O.132 

P=O.240 

584 

1/22 (5%) 

12.3% 

4/53 (8%) 

P=O.O83 

P=O.O71 

P=O.154 

584 

1/22 (5%) 

12.3% 

4/53 (8%) 

P=0.407N 

P=O.273 

P=0.198N 

503 

8/22 (36%) 

62.0% 

25/53 (47%) 

P=0.353N 

P=O.519 

P=0.077N 

542 

15/22 (68 %) 

82.1 % 

35/53 (66%) 

P=0.113N 

P=0.348N 

P=0.063N 

503 

10/22 (45%) 

73.5% 

35/53 (66%) 

P=0.540N 

P=O.637 

656 

1/17 (6%) 

13.6% 

3/53 (6%) 

P=0.500N 

P=0.540N 

P=O.637 

656 

1/17 (6%) 

13.6% 

3/53 (6%) 

P=0.500N 

P=O.553 

P=O.218 

537 

7/17 (41 %) 

66.9% 

25/53 (47%) 

P=0.577N 

P=O.O70 

P=O.O20 

392 

13/17 (76%) 

90.9% 

42/53 (79%) 

P=O.O95 

P=0.445N 

P=O.211 

3 92 

10/17 (59%) 

80.8% 

34/53 (64%) 

P=0.500N 

P=0.492N 

P=0.421N 

675 

2/28 (7%) 

9.7% 

3153 (6%) 

P=0.500N 

P=0.492N 

P=0.421N 

675 

2/28 (7%) 

9.7% 

3/53 (6%) 

P=0.500N 

P=O.O66 

P=O.362 

403 

12/28 (43%) 

66.6% 

33/53 (62 %) 

P=O.O86 

P=0.460N 

P=0.225N 

617 

2 1 /28 (75 %) 

82.7% 

35/53 (66%) 

P=0.581N 

P=O.251 

P=0.381N 

403 

14/28 (50%) 

72.1 % 

37/53 (70%) 

P=O.418 

P=O.248 

P=O.319 

538 

4/29 (14%) 

20.3% 

7154 (1 3 %) 

P=O.274 

P=O.164 

P=O.236 

538 

4/29 (14%) 

22.9% 

8/54 (15%) 

P=O.189 

P=O.404 

P=0.308N 

475 

10129 (34%) 

54.2% 

23/54 (43 %) 

P=0.389N 

P=O.268 

P=0.336N 

480 

24/29 (83%) 

87.6% 

36/54 (67%) 

P=O.554 

P=0.172N 

P=0.152N 

272 

13/29 (45%) 

64.0% 

29/54 (54%) 

P=0.135N 
196 Nickel Sulfate Hexahydrate, NTP TR 454 

TABLE B3 

(continued) 

Statistical Analysis of Primary Neoplasms in Female Rats in the 2-Year Inhalation Study of Nickel Sulfate Hexahydrate 

O mg/m3 0.12 mg/mJ 0.25 mg/m3 0.5 mg/m3 

Fisher exact test 

Cochran-Armitage test 

Logistic regression test 

Life table test 

First incidence (days) 

Terminal rate 

Adjusted rate 

Overall rate 

All Organs: Benign or Malignant Neoplasms 

P=O. 156N 

P=0.571N P=O.140 P=O.551 P=O.334 

P=0.052N P=O.O43 P=0.203N P=0.217N 

503 392 403 

20122 (91 X) 16/17 (94%) 26/28 (93%) 28/29 (97%) 

96.1% 98.1% 96.1% 98.0% 

49/53 (92 %) 52/53 (98%) 50153 (94%) 48/54 (89%) 

P=O.181 P=O.500 P=0.383N 

a Number of neoplasm-bearing animalslnumber of animals examined. Denominator is number of animals examined microscopically for adrenal gland, 

(T)Terminal sacrifice 

compare directly the overall incidence rates. For all tests, a negative trend or a lower incidence in an exposure group is indicated by N. 

(directly or indirectly) the cause of death. The logistic regression test regards these lesions as nonfatal. The Cochran-Armitage and Fisher exact tests 

pairwise comparisons between the controls and that exposed group. The life table test regards neoplasms in animals dying prior to terminal kill as being 

Beneath the control incidence are the P values associated with the trend test. Beneath the exposed group incidence are the P values corresponding to 

Observed incidence at terminal kill 

Kaplan-Meier estimated neoplasm incidence at the end of the study after adjustment for intercurrent mortality 

clitoral gland, pituitary gland, thyroid gland, and uterus; for other tissues, denominator is number of animals necropsied. 

e Not applicable; no neoplasms in animal group 
Lesions in Female Rats 197 

Historical Incidence of Lung Neoplasms in Untreated Female F344/N Ratsa 

TABLE B4 

Study 

Incidence in Controls 

Carcinoma 

Carcinoma Carcinoma or Squamous Cell 

Alveolar/bronchiolar 

Alveolar/bronchiolar Alveolar/bronchiolar Squamous Cell Adenoma or Carcinoma 

Adenoma 

Historical Incidence at Lovelace Inhalation Toxicology Research Institute 

Talcb 

Nickel Sulfate Hexahydrate 

Nickel Subsulfide 

Nickel Oxide 

1150 

0152 

2/53 

1 I53 

0150 

0152 

0153 

0153 

0150 

0152 

0153 

0153 

1 I50 

0152 

2/53 

1/53 

Overall Historical Incidence in Inhalation Studies 

Range 

Standard deviation 

Total 

0%-4% 

1.5% 

71700 (1.1%) 01700 (0%) 01700 (0 %) 

0%-4% 

1.5% 

81700 (1.1 X) 

Overall Historical Incidence in Feed Studies 

Range 

Standard deviation 

Total 

0%-10% 

2.2% 

2011.201 (1.7%) 

0%-2% 

0.8% 

511,201 (0.4%) 011,201 (0%) 

0%-10% 

2.2% 

2511,201 (2.1%) 

Results of lifetime study 

a Data as of 17 June 1994 
198 Nickel Sulfate Hexahydrate, NTP TR 454 

of Nickel Sulfate Hexahydratea 

Summary of the Incidence of Nonneoplastic Lesions in Female Rats in the 2-Year Inhalation Study 

TABLE B5 

0 mg/m3 0.12 mg/mg 0.25 mg/mJ 0.5 mg/m3 

Early deaths 

IS-Month interim evaluation 

7-Month interim evaluation 

Animals initially in study 

Disposition Summary 

Natural deaths 

Moribund 

Accidental death 

Terminal sacrifice 

Missexed 

Missing 

Survivors 

5 

5 

63 

4 

27 

22 

5 

5 

63 

4 

32 

17 

5 

5 

64 

3 

22 

28 

1 

5 

5 

65 

3 

21 

1 

1 

29 

Animals examined microscopically 63 63 63 64 

7-Month Interim Evaluation 

Hyperplasia, lymphoid 

Lymph node, bronchial 

Hematopoietic System 

Hyperplasia, lymphoid 

Lymph node, mediastinal (3) 

(5) 

(5) 

(5) 

(5) 

(4) 

(5) 

(5) 

1 (20%) 

2 (40%) 

4 (80%) 

2 (40%) 

4 (100%) 

2 (40%) 

4 (80%) 

Lung 

Respiratory System 

Interstitium, infiltration cellular 

Alveolus, proteinosis 

Inflammation, chronic active 

Hyperplasia, macrophage 

Respiratory epithelium, inflammation 

Respiratory epithelium, degeneration 

Olfactory epithelium, degeneration 

Olfactory epithelium, atrophy 

Nose 

(5) 

2 (40%) 

2 (40%) 

1 (20%) 

1 (20%) 

2 (40%) 1 (20%) 

(5) (5) 

5 (100%) 

4 (80%) 

4 (80%) 

3 (60%) 

2 (40%) 

5 (100%) 

5 (100%) 

(5) (5) 

1 (20%) 

3 (60%) 

EY e 

Special Senses System 

(1) 

Cataract 1 (100%) 

Urinary System 

Nervous System 

Musculoskeletal System 

Integumentary System 

Genital System 

General Body System 

Endocrine System 

Cardiovascular System 

Alimentary System 

Systems Examined With No Lesions Observed 

a Number of animals examined microscopically at the site and the number of animals with lesion 
Lesions in Female Rats 199 

TABLE B5 

of Nickel Sulfate Hexahydrate (continued) 

Summary of the Incidence of Nonneoplastic Lesions in Female Rats in the 2-Year Inhalation Study 

0 mg/m3 0.12 mg/m3 0.25 mg/m3 0.5 mg/m3 

~~ ~ 

Intesiine large, rectum 

Alimentary System 

IS-Month Interim Evaluation 

Parasite metazoan 

Basophilic focus 

Angiectasis 

Liver (5) 

(5) 

(5) 

(5) 

(5) 

(4) 

(5) 

(5) 

1 (20%) 

4 (80%) 

1 (20%) 

4 (80%) 3 (60%) 4 (80%) 

Pituitary gland 

Endocrine System 

cyst 

Pars distalis, hyperplasia, focal 

(5) 

1 (20%) 

(5) (5) (5) 

1 (20%) 

1 (20%) 

1 (20%) 1 (20%) 

Hyperplasia 

Bone marrow 

Hematopoietic System 

Lymph node, mesenteric 

Hyperplasia, lymphoid 

Lymph node, bronchial 

Pigmentation, hemosiderin 

~~~~~~~~ ~~~~~~~~ 

Lung 

Larynx 

Respiratory System 

(5) 

(5) 

(5) 

(4) 

(5) 

(5) 

(5) 

(5) 

Inflammation 

Interstitium, infiltration cellular 

Alveolus, proteinosis 

Alveolar epithelium, hyperplasia, focal 

Inflammation, chronic active 

Hyperplasia, macrophage 

Fibrosis 

Respiratory epithelium, inflammation 

Respiratory epithelium, degeneration 

Olfactory epithelium, inflammation 

Olfactory epithelium, degeneration 

Olfactory epithelium, atrophy 

Epithelium, hyperplasia 

1 (25%) 

4 (80%) 

3 (60%) 

1 (20%) 

3 (60%) 

1 (20%) 

5 (100%) 

1 (20%) 

5 (100%) 

5 (100%) 

3 (60%) 

1 (20%) 

1 (20%) 

2 (40%) 

1 (20%) 

1 (20%) 

1 (20%) 

1 (20%) 

Nose (5) (5) (5) (5) 

4 (80%) 

3 (60%) 

2 (40%) 

2 (40%) 

3 (60%) 

3 (60%) 2 (40%) 

Trachea (5) (5) (5) (5) 

1 (20%) 

EY e 

Special Senses System 

(1) (1) (1) 

Anterior chamber, inflammation 1 (100%) 1 (100%) 1 (100%) 

Nephropathy 

Kidney 

Urinary System 

(5) (5) (5) (5) 

3 (60%) 2 (40%) 2 (40%) 5 (100%) 
200 Nickel Sulfate Hexahydrate, NTP TR 454 

of Nickel Sulfate Hexahydrate (continued) 

Summary of the Incidence of Nonneoplastic Lesions in Female Rats in the 2-Year Inhalation Study 

TABLE B5 

0 mg/m3 0.12 mg/m3 0.25 mg/m3 0.5 mg/m3 

Nervous System 

Musculoskeletal System 

Integumentary System 

Genital System 

General Body System 

Cardiovascular System 

Systems Examined With No Lesions Observed 

15-Month Interim Evaluation (continued) 

Intestine large, colon 

Alimentary System 

2- Year Study 

Hyperplasia, lymphoid 

Parasite metazoan 

Intestine large, rectum 

Parasite metazoan 

Ulcer 

Parasite metazoan 

Inflammation, granulomatous 

Hyperplasia, lymphoid 

Intestine large, cecum 

Peyer’s patch, hyperplasia, lymphoid 

Autolysis 

Peyer’s patch, hyperplasia 

Autolysis 

Ulcer 

Hepatocyte, necrosis 

Centrilobular, atrophy 

Bile duct, hyperplasia 

Thrombosis, multiple 

Mixed cell focus 

Inflammation 

Hepatodiaphragmatic nodule 

Granuloma 

Eosinophilic focus 

Degeneration, fatty 

Degeneration, cystic 

Congestion 

Clear cell focus 

Basophilic focus 

Angiectasis 

Hemorrhage 

Acinus, atrophy 

Necrosis 

Inflammation, granulomatous 

Infiltration cellular, lymphocyte 

Intestine small, jejunum 

Intestine small, duodenum 

Intestine small, ileum 

Liver 

Pancreas 

Mesentery 

(52) 

1 (2%) 

(51) 

(51) 

1 (2%) 

1 (2%) 

1 (2%) 

(51) 

1 (2%) 

(52) 

2 (4%) 

(49) 

1 (2%) 

4 (8%) 

45 (87%) 

3 (6%) 

2 (4%) 

15 (29%) 

4 (8%) 

13 (25%) 

2 (4%) 

10 (19%) 

1 (2%) 

4 (8%) 

4 (8%) 

5 (10%) 

(52) 

(52) 

(1) 

1 (2%) 

(53) 

(53) 

(49) 

1 (2%) 

(52) 

(53) I 

1 (2%) 

3 (6%) 

1 (2%) 

(52) 

(53) 

5 (9%) 

2 (4%) 

1 (2%) 

6 (11%) 

2 (4%) 

2 (4%) 

14 (26%) 

41 (77%) 

1 (2%) 

3 (6%) 

I (13%) 

16 (30%) 

(53) 

(2) 

1 (2%) 

4 (8%) 

(54) 

1 (2%) 

1 (2%) 

(53) 

(45) 

1 (2%) 

(54) 

(53) 

3 (6%) 

(53) 

(54) 

41 (76%) 

3 (6%) 

7 (13%) 

4 (7%) 

1 (2%) 

4 (7%) 

8 (15%) 

1 (2%) 

8 (15%) 

2 (4%) 

12 (22%) 

(54) 

(1) 

1 (2%) 

1 (2%) 
Lesions in Female Rats 201 

of Nickel Sulfate Hexahydrate (continued) 

Summary of the Incidence of Nonneoplastic Lesions in Female Rats in the 2-Year Inhalation Study 

TABLE B5 

0 mg/m3 0.12 mg/m3 0.25 mg/m3 0.5 mg/m3 

Salivary glands 

Alimentary System (continued) 

2-Yeur Study (continued) 

Stomach, forestomach 

Duct, submandibular gland, hyperplasia 

Ulcer 

Inflammation 

Hyperplasia 

Hyperkeratosis 

Edema 

Inflammation 

Hyperplasia 

Erosion 

Peridontal tissue, inflammation 

Epithelium alveolus, hyperplasia, squamous 

Inflammation 

Stomach, glandular 

Tooth 

Tongue 

(53) 

(53) 

(53) 

(54) 

1 (2%) 

1 (2%) 

1 (2%) 

2 (4%) 

1 (2%) 

(53) (54) 

1 (2%) 

Heart 

Cardiovascular System 

Thrombosis 

Cardiomyopathy 

(53) (53) (53) (54) 

12 (23%) 

1 (2%) 

9 (17%) 

1 (2%) 

8 (15%) 

1 (2%) 

13 (24%) 

1 (2%) 

Endocrine System 

Congestion 

Autolysis 

Adrenil cortex 

Vacuolization cytoplasmic 

Pigmentation, hemosiderin 

Necrosis 

Hypertrophy 

Hyperplasia 

Hemorrhage 

Degeneration 

Cytoplasmic alteration 

Hyperplasia 

cyst 

Angiectasis 

Adrenal medulla 

Parathyroid gland 

Hyperplasia 

Islets, pancreatic 

Hyperplasia, focal 

Hyperplasia 

Cyst 

(53) (54) 

1 (2%) 

1 (2%) 

7 (13%) 

1 (2%) 

8 (15%) 

1 (2%) 

(51) 

6 (11%) 

8 (15%) 

(53) 

1 (2%) 

2 (4%) 

1 (2%) 

4 (8%) 

(52) 

(53) 

1 (2%) 

5 (9%) 

1 (2%) 

7 (13%) 

(53) 

8 (15%) 

(53) 

(51) 

1 (2%) 

8 (15%) 

1 (2%) 

16 (30%) 

(54) 

8 (15%) 

(49) 

(54) 

1 (2%) 

1 (2%) 
202 Nickel Sulfate Hexahydrate, NTP TR 454 

of Nickel Sulfate Hexahydrate (continued) 

Summary of the Incidence of Nonneoplastic Lesions in Female Rats in the 2-Year Inhalation Study 

TABLE B5 

0 mg/m3 0.12 mg/m3 0.25 mg/m3 0.5 mg/m3 

&Year Study (continued) 

Endocrine System (continued) 

Pars distalis, hyperplasia, focal 

Pars distalis, hyperplasia, diffuse 

Hemorrhage 

cyst 

Autolysis 

Angiectasis 

Pituitary gland 

Follicular cell, hyperplasia 

C-cell, hyperplasia 

Fibrosis 

Autolysis 

Thyroid gland 

(52) 

4 (8%) 

-5 (10%) 

12 (23%) 

4 (8%) 

(52) 

9 (17%) 

1 (2%) 

(53) (53) 

1 (2%) 

3 (6%) 

5 (9%) 

15 (28%) 

5 (9%) 

11 (21%) 

3 (6%) 

2 (4%) 

1 (2%) 

1 (2%) 

(53) (53) 

7 (13%) 

1 (2%) 

7 (13%) 

(54) 

12 (22%) 

1 (2%) 

1 (2%) 

4 (7%) 

1 (2%) 

2 (4%) 

1 (2%) 

(52) 

1 (2%) 

8 (15%) 

Tissue NOS 

General Body System 

(6) (4) (2) 

Oral, inflammation, granulomatous 

Mediastinum, inflammation 

Abdominal, polyarteritis 

Inflammation, granulomatous 

Hemorrhage 

1 (17%) 

1 (25%) 

1 (25%) 

(5) 

1 (20%) 

1 (20%) 

Genital System 

Inflammation 

Hyperplasia, squamous 

Hyperplasia 

Ectasia 

Clitoral gland 

Bilateral, cyst 

cyst 

Congestion 

Atrophy 

Endometrium, hyperplasia 

Endometrium, fibrosis 

Inflammation 

Hemorrhage 

Fibrosis 

Uterus 

Ovary 

7 (13%) 

1 (2%) 

2 (4%) 

(52) 

1 (2%) 

7 (13%) 

1 (2%) 

1 (2%) 

2 (4%) 

(53) 

4 (8%) 

(53) 

1 (2%) 

2 (4%) 

(54) 

1 (2%) 

1 (2%) 

3 (6%) 

3 (6%) 

1 (2%) 

5 (9%) 

1 (2%) 

1 (2%) 

1 (2%) 

(54) 

(54) 

1 (2%) 

1 (2%) 

Hematopoietic System 

Myeloid cell, hyperplasia 

Necrosis 

Hyperplasia, reticulum cell 

Autolysis 

Atrophy, focal 

Atrophy, diffuse 

Atrophy 

Bone marrow (52) (53) (53) (54) 

2 (4%) 

10 (19%) 

1 (2%) 

1 (2%) 

1 (2%) 

1 (2%) 

9 (17%) 

1 (2%) 

8 (15%) 10 (19%) 
Lesions in Female Rats 203 

TABLE B5 

of Nickel Sulfate Hexahydrate (continued) 

Summary of the Incidence of Nonneoplastic Lesions in Female Rats in the 2-Year Inhalation Study 

0 mg/m3 0.12 mg/m3 0.25 mg/m3 0.5 mg/m’ 

Lymph node 

Hematopoietic System (continued) 

&Year Study (continued) 

Lymph node, bronchial 

Iliac, hyperplasia, lymphoid 

Hyperplasia, plasma cell 

Hyperplasia, lymphoid 

Congestion 

Inflammation, granulomatous 

Hyperplasia, plasma cell 

Hyperplasia, lymphoid 

Autolysis 

Lymph node, mandibular 

Pigmentation, hemosiderin 

Inflammation, granulomatous 

Inflammation 

Infarct 

Hyperplasia, macrophage 

Hyperplasia, lymphoid 

Hyperplasia, histiocytic 

Edema 

Congestion 

Autolysis 

Pigmentation 

Inflammation, granulomatous 

Hyperplasia, lymphoid 

Hyperplasia, histiocytic 

Hemorrhage 

Congestion 

Autolysis 

Necrosis 

Metaplasia, osseous 

Inflammation, focal 

Infarct 

Hyperplasia, RE cell 

Hyperplasia, histiocytic 

Hemorrhage 

Hematopoietic cell proliferation 

Fibrosis 

Autolysis 

Atrophy 

Angiectasis 

Autolysis 

Atrophy 

Lymph node, mesenteric 

Lymph node, mediastinal 

Spleen 

Thymus 

2 (4%) 

2 (4%) 

(52) 

2 (4%) 

3 (6%) 

1 (2%) 

(53) 

1 (2%) 

1 (2%) 

2 (4%) 

1 (2%) 

1 (2%) 

1 (2%) 

3 (6%) 

1 (2%) 

1 (2%) 

1 (2%) 

(48) 

1 (2%) 

2 (4%) 

1 (2%) 

1 (2%) 

1 (2%) 

3 (6%) 

1 (2%) 

1 (2%) 

1 (2%) 

(48) 

14 (29%) 

(50) 

6 (12%) 

2 (4%) 

4 (8%) 

1 (2%) 

1 (2%) 

1 (2%) 

2 (4%) 

(49) 

19 (39%) 

1 (2%) 

1 (2%) 

1 (2%) 

2 (4%) 

(50) 

7 (14%) 

1 (2%) 

1 (2%) 

1 (2%) 

4 (8%) 

(54) 

3 (6%) 

3 (6%) 

1 (2%) 

1 (2%) 
204 Nickel Sulfate Hexahydrate, NTP TR 454 

of Nickel Sulfate Hexahydrate (continued) 

Summary of the Incidence of Nonneoplastic Lesions in Female Rats in the 2-Year Inhalation Study 

TABLE B5 

0 mg/m3 0.12 mg/m3 0.25 mg/m3 0.5 mg/m3 

Integumentary System 

Epithelium, hyperplasia 

Duct, hyperplasia 

Duct, ectasia 

Hyperplasia, focal 

Hyperplasia 

Mammary gland 

Dermis, edema 

Inflammation 

Cyst epithelial inclusion 

Skin 

Bone 

Musculoskeletal System 

(53) (53) (53) (54) 

Tibia, fracture 

Ligament, intervertebral disc, degeneration 

Hyperostosis 

Fracture 

Hemorrhage 

Skeletal muscle 

1 (2%) 

2 (4%) 

1 (2%) 

1 (2%) 

4 (8%) 1 (2%) 3 (6%) 

(1) 

1 (100%) 

Brain 

Nervous System 

(52) (53) (53) (54) 

Ventricle, hydrocephalus 

Meninges, inflammation 

Necrosis 

Hydrocephalus 

Hemorrhage 

Degeneration 

Compression 

Autolysis 

Meninges, hemorrhage 

1 (2%) 

5 (9%) 

1 (2%) 

9 (17%) 14 (26%) 

1 (2%) 

1 (2%) 

1 (2%) 

1 (2%) 

5 (9%) 

2 (4%) 

1 (2%) 

1 (2%) 

1 (2%) 

Spinal cord (1) 

1 (100%) 

Larynx 

Respiratory System 

(51) (53) (52) (53) 

Metaplasia, squamous 

Inflammation 

Hyperplasia 

Inflammation, chronic active 

Hyperplasia, macrophage 

Hemorrhage 

Fibrosis 

Cyst, squamous 

Congestion 

1 (2%) 

12 (23%) 

1 (2%) 

1 (2%) 

10 (19%) 

1 (2%) 

7 (13%) 

1 (2%) 

1 (2%) 

15 (28%) 

2 (4%) 

9 (18%) 21 (40%) 

Lung (52) (53) (53) (54) 

9 (17%) 

8 (15%) 

1 (2%) 

14 (27%) 

1 (2%) 

2 (4%) 

49 (92%) 

32 (60%) 

45 (85%) 

52 (96%) 

45 (83%) 

49 (91%) 

13 (25%) 

Inflammation, suppurative 

Inflammation, granulomatous 

1 (2%) 

1 (2%) 
Lesions in Female Rats 205 

of Nickel Sulfate Hexahydrate (continued) 

Summary of the Incidence of Nonneoplastic Lesions in Female Rats in the 2-Year Inhalation Study 

TABLE B5 

0 mg/m3 0.12 mg/m3 0.25 mg/m3 0.5 mg/m3 

Lung (continued) 

Respiratory System (continued) 

2-YeUr study (continued) 

Interstitium, infiltration cellular 

Alveolus, proteinosis 

Alveolar epithelium, metaplasia, squamous 

Alveolar epithelium, hyperplasia, focal 

Alveolar epithelium, hyperplasia 

Vomeronasal organ, inflammation 

Respiratory epithelium, memplasia, squamous 

Respiratory epithelium, inflammation 

Respiratory epithelium, hyperplasia 

Respiratory epithelium, erosion 

Respiratory epithelium, degeneration 

Olfactory epithelium, metaplasia, squamous 

Olfactory epithelium, metaplasia 

Olfactory epithelium, inflammation 

Olfactory epithelium, erosion 

Olfactory epithelium, degeneration 

Olfactory epithelium, atrophy 

Nasopharyngeal duct, inflammation 

Nasopharyngeal duct, hyperplasia 

Nasolacrimal duct, inflammation 

Nasolacrimal duct, hyperplasia 

Nasolacrimal duct, ectasia 

Thrombosis, multiple 

Thrombosis 

Hemorrhage 

Congestion 

Metaplasia, squamous 

Inflammation 

Hyperplasia 

Autolysis 

Nose 

Trachea 

(52) 

13 (25%) 

1 (2%) 

5 (10%) 

(51) 

1 (2%) 

1 (2%) 

4 (8%) 

5 (10%) 

41 (80%) 

11 (22%) 

1 (2%) 

1 (2%) 

1 (2%) 

1 (2%) 

1 (2%) 

13 (25%) 

9 (18%) 

(52) 

(53) 

3 (6%) 

9 (17%) 

(52) 

4 (8%) 

18 (35%) 

1 (2%) 

1 (2%) 

1 (2%) 

4 (8%) 

8 (15%) 

17 (33%) 

14 (27%) 

(53) 

1 (2%) 

(53) 

4 (8%) 

22 (42%) 

7 (13%) 

(53) 

5 (9%) 

1 (2%) 

11 (21%) 

1 (2%) 

1 (2%) 

1 (2%) 

1 (2%) 

1 (2%) 

10 (19%) 

17 (32%) 

1 (2%) 

5 (9%) 

(53) 

1 (2%) 

1 (2%) 

1 (2%) 

(54) 

10 (19%) 

49 (91%) 

4 (7%) 

9 (17%) 

1 (2%) 

(54) 

1 (2%) 

3 (6%) 

1 (2%) 

1 (2%) 

12 (22%) 

7 (13%) 

1 (2%) 

1 (2%) 

8 (15%) 

1 (2%) 

2 (4%) 

13 (24%) 

17 (31%) 

(54) 

1 (2%) 

EY e 

Special Senses System 

Posterior chamber, inflammation 

Cornea, fibrosis 

Synechia 

Phthisis bulbi 

Inflammation 

Hemorrhage 

Cataract 

(1) (4) (1) (6) 

2 (33%) 

3 (50%) 

1 (17%) 

1 (17%) 

1 (25%) 

1 (25%) 

1 (25%) 

1 (100%) 

1 (100%) 
206 Nickel Sulfate Hexahydrate, NTP TR 454 

of Nickel Sulfate Hexahydrate (continued) 

Summary of the Incidence of Nonneoplastic Lesions in Female Rats in the 2-Year Inhalation Study 

TABLE B5 

0 mg/m3 0.12 mg/m’ 0.25 mg/m3 0.5 mg/m3 

Kidney 

Urinary System 

2- Yew (continued) 

Renal tubule, pigmentation 

Renal tubule, necrosis, acute 

Renal tubule, necrosis 

Renal tubule, degeneration 

Pelvis, dilatation 

Pigmentation 

Nephropathy 

Inflammation, granulomatous 

Infarct 

Degeneration, fatty 

cyst 

Congestion 

Autolysis 

Inflammation, granulomatous 

Inflammation 

Uri~~y bladder 

40 (77%) 

1 (2%) 

1 (2%) 

3 (6%) 

1 (2%) 

(53) 

(53) 

1 (2%) 

1 (2%) 

1 (2%) 

39 (74%) 

1 (2%) 

8 (15%) 

(53) 

39 (74%) 

1 (2%) 

1 (2%) 

1 (2%) 

1 (2%) 

2 (4%) 

8 (15%) 

(53) 

(54) 

2 (4%) 

1 (2%) 

39 (72%) 

1 (2%) 

6 (11%) 

1 (2%) 

(54) 

1 (2%) 
207 

OF NICKEL SULFATE HEXAHYDRATE 

SUMMARY OF LESIONS IN MALE MICE 

APPENDIX C 

IN THE 2-YEAR INHALATION STUDY 

TABLE C5 Summary of the Incidence of Nonneoplastic Lesions in Male Mice 

TABLE C4b Historical Incidence of Hepatocellular Neoplasms 

TABLE C4a Historical Incidence of Alveolar/bronchiolar Neoplasms 

TABLE C3 Statistical Analysis of Primary Neoplasms in Male Mice 

TABLE C2 Individual Animal Tumor Pathology of Male Mice 

TABLE C1 Summary of the Incidence of Neoplasms in Male Mice 

in the 2-Year Inhalation Study of Nickel Sulfate Hexahydrate 

in Untreated Male B6C3Fl Mice 

in Untreated Male B6C3Fl Mice 

in the 2-Year Inhalation Study of Nickel Sulfate Hexahydrate 

in the 2-Year Inhalation Study of Nickel Sulfate Hexahydrate 

in the 2-Year Inhalation Study of Nickel Sulfate Hexahydrate ................ 

241 

240 

239 

236 

212 

208 

................ 

................ 

................................... 

................................... 

................ 
208 Nickel Sulfate Hexahydrate, NTP TR 454 

Summary of the Incidence of Neoplasms in Male Mice in the 2-Year Inhalation Study of Nickel Sulfate Hexahydratea 

TABLE C1 

O mg/m3 0.25 mg/m3 0.5 mg/m3 1 mg/m3 

Early deaths 

15-Month interim evaluation 

%Month interim evahation 

Animals initially in study 

Disposition Summary 

Terminal sacrifice 

Natural deaths 

Moribund 

Survivors 

Animals examined microscopically 

5 

5 

71 

5 

30 

26 

71 

5 

5 

71 

9 

29 

23 

71 

5 

5 

72 

9 

29 

24 

72 

5 

5 

72 

10 

21 

25 

72 

Skin 

Integumentary System 

7-Month Interim Evaluation 

Subcutaneous tissue, mast cell tumor NOS 

(1) 

1 (100%) 

Urinary System 

Special Senses System 

Respiratory System 

Nervous System 

Musculoskeletal System 

Hematopoietic System 

Genital System 

General Body System 

Endocrine System 

Cardiovascular System 

Alimentary System 

Systems Examined With No Neoplasms Observed 

Liver 

Alimentary System 

15-Month Interim Evaluation 

(5) (5) (5) (5) 

Hepatocellular adenoma 2 (40%) 1 (20%) 1 (20%) 

Capsule, adenoma 

Adrenal cortex 

Endocrine System 
Lesions in Male Mice 209 

(continued) 

Summary of the Incidence of Neoplasms in Male Mice in the 2-Year Inhalation Study of Nickel Sulfate Hexahydrate 

TABLE C1 

O mg/m3 0.25 mg/m3 0.5 mg/m3 1 mg/m3 

Urinary System 

Special Senses System 

Respiratory System 

Nervous System 

Musculoskeletal System 

Integumentary System 

Hematopoietic System 

Genital System 

General Body System 

Cardiovascular System 

Systems Examined With No Neoplasms Observed 

15-Month Interim Evaluation (continued) 

2- Year Study 

Liver 

Intestine large, colon 

Gallbladder 

Alimentary System 

Carcinoma, metastatic, liver 

Histiocytic sarcoma 

HepatoceKular adenoma, multiple 

Hepatocellular adenoma 

Hepatocellular carcinoma, multiple 

Hepatocellular carcinoma 

Hemangiosarcoma 

Carcinoma 

Histiocytic sarcoma 

Carcinoma, metastatic, liver 

Histiocytic sarcoma 

Carcinoma, metastatic, liver 

Mesentery 

Pancreas 

Salivary glands 

17 (28%) 

1 (2%) 

(1) 

1 (100%) 

(61) 

1 (2%) 

1 (2%) 

1 (2%) 

6 (10%) 

3 (5%) 

8 (13%) 

(2) 

1 (2%) 

(61) 

3 (5%) 

2 (3%) 

1 (2%) 

18 (29%) 

12 (19%) 

(1) 

10 (17%) 

2 (3%) 

8 (13%) 

None 

Cardiovascular System 

Endocrine System 

Extra adrenal tissue, histiocytic sarcoma. 

Capsule, adenoma 

Adrenal cortex 

Thyroid gland 

Adenoma 

Islets, pancreatic 

Follicular cell, adenoma 

(61) (60) (61) (60) 

1 (2%) 

1 (2%) 

1 (2%) 3 (5%) 1 (2%) 

(61) 

(61) 

(61) 

(60) 

(61) 

(57) 

(62) 

(58) 

1 (2%) 

' 1 (2%) 

2 (3%) 1 (2%) 

Tissue NOS 

General Body System 

(1) (2) 

Hemangiosarcoma, metastatic, bone 1 (100%) 
210 Nickel Sulfate Hexahydrate, NTP TR 454 

(continued) 

Summary of the Incidence of Neoplasms in Male Mice in the 2-Year Inhalation Study of Nickel Sulfate Hexahydrate 

TABLE C1 

O mg/m3 0.25 mg/m3 0.5 mg/m3 1 mg/m3 

Epididymis 

Genital System 

2-YeUr Study (continued) 

Histiocytic sarcoma 

Histiocytic sarcoma 

Carcinoma, metastatic, liver 

Testes 

Bone marrow 

Hematopoietic System 

Histiocytic sarcoma 

Hemangiosarcoma, metastatic, bone 

Renal, histiocytic sarcoma 

Renal, carcinoma, metastatic, liver 

Pancreatic, carcinoma, metastatic, liver 

Iliac, histiocytic sarcoma 

Histiocytic sarcoma 

Carcinoma, metastatic, liver 

Lymph node, bronchial 

Spleen 

Lymph node, mediastinal 

Lymph node, mesenteric 

Lymph node, mandibular 

Lymph node 

Histiocytic sarcoma 

Hemangiosarcoma 

Thymus 

(61) 

1 (2%) 

1 (4%) 

1 (4%) 

(46) 

1 (2%) 

1 (5%) 

(49) (45) 

Skin 

Integumentary System 

Bone 

Musculoskeletal System 

Hemangiosarcoma 

None 

Nervous System 

Lung 

Larynx 

Respiratory System 

(61) 

(59) 

(61) 

(59) 

(62) 

(58) 

(61) 

(62) 

Hepatocellular carcinoma, metastatic, liver 

Carcinoma, metastatic, liver 

Alveolar/bronchiolar carcinoma, multiple 

Alveolar/bronchiolar carcinoma 

AIveolar/bronchiolar adenoma, multiple 2 (3%) 

Alveolar/bronchiolar adenoma 3 (5%) 4 (7%) 

2 (3%) 

3 (5%) 

1 (2%) 

3 (5%) 

1 (2%) 

3 (5%) 

.3 (5%) 

3 (5%) 

1 (2%) 

4 (7%) 

9 (15%) 10 (16%) 

1 (2%) 

1 (2%) 

2 (3%) 
Lesions in Male Mice 211 

(continued) 

Summary of the Incidence of Neoplasms in Male Mice in the 2-Year Inhalation Study of Nickel Sulfate Hexahydrate 

TABLE C1 

0 mg/m3 0.25 mg/m3 0.5 mg/m3 1 mg/m3 

Ear 

Special Senses System 

&Year study (continued) 

Adenoma 

Harderian gland 

Fibrosarcoma 

Urinary bladder 

Kidney 

Urinary System 

Histiocytic sarcoma 

Histiocytic sarcoma 

Multiple organsb 

Systemic Lesions 

Lymphoma malignant 

Histiocytic sarcoma 

Total animals with primary neoplasms' 

Neoplasm Summary 

2-Year study 

15-Month interim evaluation 

7-Month interim evaluation 

2-Year study 

15-Month interim evaluation 

'I-Month interim evaluation 

15-Month interim evaluation 

2-Year study 

15-Month interim evaluation 

benign or malignant 

2-Year study 

2-Year study 

2-Year study 

2-Year study 

2-Year study 

7-Month interim evaluation 

7-Month interim evaluation 

Total primary neoplasms 

Total animals with benign neoplasms 

Total benign neoplasms 

Total animals with uncertain neoplasms - 

Total metastatic neoplasms 

Total animals with metastatic neoplasms 

Total malignant neoplasms 

Total animals with malignant neoplasms 

Total uncertain neoplasms 

35 

2 

1 

41 

1 

38 

2 

27 

44 

2 

1 

50 

2 

54 

1 

31 

22 

2 

16 

2 

24 

1 

16 

24 

2 

17 

2 

28 

1 

18 

2 

2 

13 

20 22 25 13 

26 27 26 

3 2 3 

11 2 3 

1 

1 

a Number of animals examined microscopically at the site and the number of animals with neoplasm 

Primary neoplasms: all neoplasms except metastatic neoplasms 

Number of animals with any tissue examined microscopically 
212 Nickel Sulfate Hexahydrate, NTP TR 454 

TABLE C2 

0 mg/m3 

Individual Animal Tumor Pathology of Male Mice in the 2-Year Inhalation Study of Nickel Sulfate Hexahydrate: 

0752466235800305778178944 

3895111555677788999000011 

2234555555555555555666666 

2271936902074518793085148 

7325067441602113550304755 

0000000000000000000000000 

Number of Days on Study 

Carcass ID Number 

Alimentary System 

Gallbladder 

Esophagus 

Liver 

Intestine small, ileum 

Intestine small, jejunum 

Intestine small, duodenum 

Intestine large, cecum 

Intestine large, rectum 

Intestine large, colon 

Carcinoma, metastatic, liver 

Hepatocellular adenoma, multiple 

Hepatocellular adenoma 

Hepatocellular carcinoma 

Hemangiosarcoma 

Carcinoma 

Carcinoma, metastatic, liver 

Carcinoma, metastatic, liver 

Pharynx 

Pancreas 

Mesentery 

Salivary glands 

++++++++++M+++++MM+++++++ 

......................... 

......................... 

......................... 

......................... 

......................... 

++++++++++++++++++++++M++ 

++++IM++++++++++++++++M++ 

++++++++++++++++++++++M++ 

X 

X 

X x xx xx 

X xx X X X X 

X 

X 

+ 

......................... 

'+ 

......................... X 

Stomach, glandular 

Stomach, forestomach 

......................... 

......................... 

Heart 

Cardiovascular System ......................... 

Adrenal cortex 

Endocrine System 

Thyroid gland 

Pituitary gland 

Parathyroid gland 

Islets, pancreatic 

Adrenal medulla 

Capsule, adenoma 

Tissue NOS 

General Body System 

......................... 

......................... 

++++++++MIM+M++++++++++++ 

"+I ++M++++I +++++++++++++ ......................... 

......................... 

Hemangiosarcoma, metastatic, bone 

Epididymis 

Genital System 

Histiocytic sarcoma 

Carcinoma, metastatic, liver 

Prostate 

Preputial gland 

Penis 

......................... X 

++ 

......................... 

......................... + 

A: Autolysis precludes examination 

+ : Tissue examined microscopically 

I: Insufficient tissue 

M: Missing tissue 

Blank: Not examined 

X: Lesion present 
Lesions in Male Mice 213 

0 mg/m3 (continued) 

Individual Animal Tumor Pathology of Male Mice in the 2-Year Inhalation Study of Nickel Sulfate Hexahydrate: 

TABLE C2 

6702256784777777777888888 

1244467883333333333333333 

6666666667777717771777777 

8172506218404561789547916 

7242771004013336666011245 

0000000000000000000000000 

Number of Days on Study 

Carcass ID Number 

Alimentary System 

Gallbladder 

Esophagus 

Liver 

Intestine small, ileum 

Intestine small, jejunum 

Intestine small, duodenum 

Intestine large, cecum 

Intestine large, rectum 

Intestine large, colon 

Carcinoma, metastatic, liver 

Hepatocellular adenoma, multiple 

Hepatocellular adenoma 

Hepatocellular carcinoma 

Hemangiosarcoma 

Carcinoma 

Carcinoma, metastatic, liver 

Carcinoma, metastatic, liver 

Pharynx 

Pancreas 

Mesentery 

Stomach, glandular 

Stomach, forestomach 

Salivary glands 

++++++M++++++++++++++++++ 

+++++++++++++++++++M+++++ 

......................... 

+++++++++++++M+++++++++++ 

......................... 

......................... 

......................... 

I++++++++++++++++++++++++ 

......................... 

X 

X X 

X xx xxx 

X 

......................... 

......................... 

......................... 

......................... 

Adrenal cortex 

Endocrine System 

Heart 

Cardiovascular System ......................... 

......................... Capsule, adenoma 

Thyroid gland 

Pituitary gland 

Parathyroid gland 

Islets, pancreatic 

Adrenal medulla 

......................... 

++++M+++IM+++++++++++++++ 

M++++++MM+++++++M+++++++M 

......................... 

......................... 

Tissue NOS 

General Body System 

X 

+ 

Hemangiosarcoma, metastatic, bone 

Epididymis 

Genital System .......................... 

Histiocytic sarcoma 

Carcinoma, metastatic, liver 

X 

Prostate 

Preputial gland 

Penis + 

+++M+++++++++++++++++++++ 

+++++M+++++++++++++++++++ 
214 Nickel Sulfate Hexahydrate, NTP TR 454 

TABLE C2 

0 mg/m3 (continued) 

Individual Animal Tumor Pathology of Male Mice in the 2-Year Inhalation Study of Nickel Sulfate Hexahydrate: 

89999999999 

33333333333 

71111777117 

Number of Days on Study 

Carcass ID Number 

68068924653 

61222344451 

00000000000 

Tumors 

Tissues/ 

Total 

Gallbladder 

Esophagus 

Alimentary System 

Liver 

Intestine small, ileum 

Intestine small, jejunum 

Intestine small, duodenum 

Intestine large, cecum 

Intestine large, rectum 

Intestine large, colon 

Carcinoma, metastatic, liver 

Hepatocellular adenoma, multiple 

Hepatocellular adenoma 

. Hepatocellular carcinoma 

Hemangiosarcoma 

Carcinoma 

Carcinoma, metastatic, liver 

Carcinoma, metastatic, liver 

Pharynx 

Pancreas 

Mesentery 

Stomach, glandular 

Stomach, forestomach 

Salivary glands 

++++++M++++ 

+++++++++++ 

+++++++++++ 

++++++++++M 

+++++++++++ 

+++++++++++ 

+++M+++++++ 

++I +++++++M 

+++++++++++ 

X 

xx 

+++++++++++ 

+++++++++++ 

+++++++++++ 

+++++++++++ 

61 

61 

61 

1 

1 

61 

1 

1 

1 

17 

10 

1 

1 

61 

59 

61 

61 

59 

55 

60 

1 

56 

60 

Heart 

Cardiovascular System 

+++++++++++ 61 

Adrenal cortex 

Endocrine System 

Thyroid gland 

Pituitary gland 

Parathyroid gland 

Islets, pancreatic 

Adrenal medulla 

Capsule, adenoma 

+++++++++++ 

X 

+++++++++++ 

+++++M+++++ 

I ++++++M+++ 

+++++++++++ 

+++++++++++ 

61 

53 

49 

61 

61 

1 

61 

Tissue NOS 

General Body System 

Hemangiosarcoma, metastatic, bone 1 

1 

Epididymis 

Genital System 

Histiocytic sarcoma 

Carcinoma, metastatic, liver 

Prostate 

Preputial gland 

Penis 

+++++++++++ 

+++++++++++ 

+++++M+++++ 

60 

59 

4 

1 

1 

61 
Lesions in Male Mice 215 

0 mg/m3 (continued) 

Individual Animal Tumor Pathology of Male Mice in the 2-Year Inhalation Study of Nickel Sulfate Hexahydrate: 

TABLE C2 

Number of Days on Study 

0752466235800305778178944 

3895111555677788999000011 

2234555555555555555666666 

2271936902074518793085148 

7325067441602113550304755 

0000000000000000000000000 

Carcass ID Number 

Testes 

Seminal vesicle 

Genital System (continued) 

......................... 

......................... 

Lymph node 

Bone marrow 

Hematopoietic System 

......................... 

Carcinoma, metastatic, liver 

Renal, carcinoma, metastatic, liver 

Pancreatic, carcinoma, metastatic, liver 

Hemangiosarcoma, metastatic, bone 

++ ++ +++++ +++ + 

X 

X 

X 

Lymph node, mandibular 

Lymph node, bronchial ++MI +++MI +++I +M+++++++M++ 

++++++M++++++M+I+++++++++ 

Thymus 

Spleen 

Lymph node, mediastinal 

Lymph node, mesenteric 

......................... 

......................... 

MMMMMM++MM+++MMMMM+MMMIM+ 

+++++++++I+++++M+++++++++ 

Skin 

Mammary gland 

Integumentary System 

Bone 

Musculoskeletal System 

......................... 

......................... 

......................... Hemangiosarcoma 

Brain 

Nervous System 

Lung 

Larynx 

Respiratory System 

......................... 

++M++++++++++++++++++++++ 

Hepatocellular carcinoma, metastatic, liver 

Carcinoma, metastatic, liver 

Alveolar/bronchiolar carcinoma 

Alveolar/bronchiolar adenoma, multiple 

Alveolar/bronchiolar adenoma 

X 

X 

X 

Trachea 

Nose 

......................... 

......................... 

Ear 

Special Senses System 

Fibrosarcoma 

+ 

Urinary bladder 

Urethra 

Ureter 

Kidney 

Urinary System 

......................... + 

++ ++ + ......................... 

Multiple organs 

Systemic Lesions 

......................... 

Lymphoma malignant 

Histiocytic sarcoma 
Nickel Sulfate Hexahydrate, NTP TR 454 

TABLE C2 

0 mg/m3 (continued) 

Individual Animal Tumor Pathology of Male Mice in the 2-Year Inhalation Study of Nickel Sulfate Hexahydrate: 

6702256784777777777888888 

1244467883333333333333333 

6666666667777777777777777 

8172506218404561789547916 

7242771004013336666011245 

0000000000000000000000000 

Number of Days on Study 

Carcass ID Number 

Genital System (continued) 

Testes 

Seminal vesicle 

......................... 

......................... 

Lymph node 

Bone marrow 

Hematopoietic System 

Carcinoma, metastatic, liver 

Renal, carcinoma, metastatic, liver 

Pancreatic, carcinoma, metastatic, liver 

Hemangiosarcoma, metastatic, bone 

Lymph node, bronchial 

Thymus 

Spleen 

Lymph node, mediastinal 

Lymph node, mesenteric 

Lymph node, mandibular 

......................... X 

++ +++ + ++ 

++++I+MM+M+++++++M+++++++ 

+++M+++++++++++++I+M+++++ 

......................... 

+MMM++MMMMM+I ++"+MI +"MI 

+++++++++++++++M++++++I++ 

++++++++++M++++++++M+++++ 

Skin 

Mammary gland 

Integumentary System 

......................... 

......................... 

Bone 

Musculoskeletal System ......................... Hemangiosarcoma X 

Brain 

Nervous System 

......................... 

Larynx 

Respiratory System 

+++++++++++++++++I+++++++ 

Lung ......................... 

Hepatocellular carcinoma, metastatic, liver 

Carcinoma, metastatic, liver 

Alveolar/bronchiolar carcinoma 

Alveolarlbronchiolar adenoma, multiple 

Alveolar/bronchiolar adenoma X 

X xx 

X X 

X 

Ear 

Special Senses System 

Trachea 

Nose 

......................... 

......................... 

X 

+ 

Kidney 

Urinary System 

Fibrosarcoma 

......................... 

Urinary bladder 

Urethra 

Ureter + 

+ + ......................... 

Multiple organs 

Systemic Lesions ......................... 

Lymphoma malignant 

Histiocytic sarcoma X 

X 
Lesions in Male Mice 217 

0 mg/m3 (continued) 

Individual Animal Tumor Pathology of Male Mice in the 2-Year Inhalation Study of Nickel Sulfate Hexahydrate: 

TABLE C2 

77777777777 

Number of Days on Study 

89999999999 

33333333333 

Carcass ID Number 

68068924653 

61222344457 

00000000000 

Tumors 

Tissues/ 

Total 

Testes 

Seminal vesicle 

Genital System (continued) 

+++++++++++ 

+++++++++++ 

61 

61 

Lymph node 

Bone marrow 

Hematopoietic System 

Hemangiosarcoma, metastatic, bone 

+++++++++++ 

+ ++ 

Carcinoma, metastatic, liver 

Renal, carcinoma, metastatic, liver 

Pancreatic, carcinoma, metastatic, liver 

Lymph node, mandibular 

Lymph node, bronchial +I I M+++++++ 

+++++++++++ 

Thymus 

Spleen 

Lymph node, mediastinal 

Lymph node, mesenteric 

++++++++MM+ 

+++++++++++ 

I M+I M+M+MMM 

+++++++M+++ 

55 

61 

18 

56 

56 

1 

46 

1 

1 

24 

1 

61 

Integumentary System 

Skin 

Mammary gland 

+++++++++++ 

+++++++++++ 

61 

61 

Bone 

Musculoskeletal System 

+++++++++++ 61 

Hemangiosarcoma 1 

Brain 

Nervous System 

+++++++++++ 61 

Lung 

Larynx 

Respiratory System 

+++++++++++ 

+++++++++++ 

61 

61 

1 

1 

9 

2 

3 

61 

59 

Hepatocellular carcinoma, metastatic, liver 

Carcinoma, metastatic, liver 

Alveolar/bronchiolar carcinoma 

Alveolarlbronchiolar adenoma, multiple 

Alveolar/bronchiolar adenoma X X 

xxx X 

Ear 

Special Senses System 

Trachea 

Nose 

+++++++++++ 

+++++++++++ 

1 

2 

Fibrosarcoma 

Urinary bladder 

Urethra 

Ureter 

Kidney 

Urinary System 

+++++++++++ 

M++++++++++ 

+ ++ 

60 

10 

2 

61 

Multiple organs 

Systemic Lesions 

Lymphoma malignant 

Histiocytic sarcoma 

+++++++++++ 

X 2 

1 

61 
218 Nickel Sulfate Hexahydrate, NTP TR 454 

TABLE C2 

8265080667922924779144441 

I282031111455566666889912 

1123445555555555555555566 

2385488162852167076065612 

0109178686203969019826308 

2221211111222111221121221 

Number of Days on Study 

Carcass ID Number 

Liver 

Intestine small, ileum 

Intestine small, jejunum 

Intestine small, duodenum 

Intestine large, cecum 

Intestine large, rectum 

Intestine large, colon 

Gallbladder 

Esophagus 

Alimentary System 

Histiocytic sarcoma 

Hepatocellular adenoma, multiple 

Hepatocellular adenoma 

Hepatocellular carcinoma, multiple 

Hepatocellular carcinoma 

Histiocytic sarcoma 

MesenteIy 

......................... 

+++++++++++++++A+++++++++ 

......................... 

+++++++++++++++A+++++++++ 

......................... 

++++++++++++++++++++++M+M 

......................... 

......................... 

.......................... 

X xxx 

X X X 

X 

+ 

X 

Pancreas ......................... 

Stomach, glandular 

Stomach, forestomach 

Salivary glands 

Histiocytic sarcoma 

+++++++++++++++++++++I+++ 

......................... 

......................... X 

Heart 

Cardiovascular System ......................... 

Endocrine System 

Thyroid gland 

Pituitary gland 

Parathyroid gland 

Islets, pancreatic 

Adrenal medulla 

Extra adrenal tissue, histiocytic sarcoma 

Capsule, adenoma 

Adrenal cortex 

Follicular cell, adenoma 

......................... X 

X 

......................... 

M+++++++M++++++++M++++M++ 

MMMM+MMM++++++M+M+++MMM++ 

......................... 

MI1 ...................... 

X 

Tissue NOS 

General Body System 

Testes 

Seminal vesicle 

Prostate 

Preputial gland 

Penis 

Epididymis 

Genital System ......................... 

......................... 

......................... 

M++++++++++++++++++++++++ 

I++++++++++++++++++++++++ 

+ ++ 
Lesions in Male Mice 219 

0.25 mg/d (continued) 

Individual Animal Tumor Pathology of Male Mice in the 2-Year Inhalation Study of Nickel Sulfate Hexahydrate: 

TABLE C2 

Number of Days on Study 

0149331749401777177778888 

4444661899122333333333333 

6666666666777777117777777 

Carcass ID Number 

8979007343454342334985691 

6166230882287661199937718 

1211222112211111111121111 

Liver 

Intestine small, ileum 

Intestine small, jejunum 

Intestine small, duodenum 

Intestine large, cecum 

Intestine large, rectum 

Intestine large, colon 

Gallbladder 

Esophagus 

Alimentary System 

Histiocytic sarcoma 

Hepatocellular adenoma, multiple 

Hepatocellular adenoma 

Hepatocellular carcinoma, multiple 

Hepatocellular carcinoma 

Pancreas 

Histiocytic sarcoma 

Mesentery 

Stomach, glandular 

Stomach, forestomach 

Salivary glands 

Histiocytic sarcoma 

......................... 

......................... 

......................... 

......................... 

++++++++++++++++++++M++++ 

......................... 

......................... 

++++++++M++++++++++++++++ 

......................... 

X xx 

x xx 

xx x 

X 

+ 

.......................... 

......................... 

......................... 

......................... 

Heart 

Cardiovascular System 

......................... 

Endocrine System 

Extra adrenal tissue, histiocytic sarcoma 

Capsule, adenoma 

Adrenal cortex ++++++++++++++++++++M++++ 

Thyroid gland 

Pituitary gland 

Parathyroid gland 

Islets, pancreatic 

Adrenal medulla 

......................... 

M+++++++M++++++++++++++++ 

++M+IM+++++M++++M++M++M++ 

......................... 

++++++++++++++++++++M++++ 

Follicular cell, adenoma X 

Tissue NOS 

General Body System 

+ + 

Testes 

Seminal vesicle 

Prostate 

Preputial gland 

Penis 

Epididymis 

Genital System 

......................... + 

......................... 

......................... 

......................... 

......................... 
220 Nickel Sulfate Hexahydrate, NTP TR 454 

TABLE C2 

0.25 mg/m3 (continued) 

Individual Animal Tumor Pathology of Male Mice in the 2-Year Inhalation Study of Nickel Sulfate Hexahydrate: 

77777777777 

Number of Days on Study 

88889999999 

33333333333 

08957226824 

99027911123 

11221122222 

Carcass ID Number 

Tumors 

Tissues1 

Total 

Liver 

Intestine small, ileum 

Intestine small, jejunum 

Intestine small, duodenum 

Intestine large, cecum 

Intestine large, rectum 

Intestine large, colon 

Gallbladder 

Esophagus 

Alimentary System 

Hepatocellular carcinoma, multiple 

Hepatocellular carcinoma 

+++++++++++ 

+++++++++++ 

+++++++++++ 

+++++++++++ 

+++++++++++ 

I ++++++++++ 

+++++++++++ 

+++++++M+++ 

+++++++++++ 

X 

61 

60 

61 

60 

60 

57 

61 

59 

61 

3 

8 

Hepatocellular adenoma 6 

Histiocytic sarcoma 

Histiocytic sarcoma 

Hepatocellular adenoma, multiple 

Pancreas 

Mesentery 

+++++I +++++ 

Stomach, glandular 

Stomach, forestomach 

Salivary glands 

Histiocytic sarcoma 

+++++++++++ 

+++++++++++ 

+++++++++++ 

1 

2 

1 

1 

60 

60 

61 

1 

60 

Heart 

Cardiovascular System 

+++++++++++ 61 

Endocrine System 

Extra adrenal tissue, histiocytic sarcoma 

Capsule, adenoma 

Adrenal cortex +++++++++++ 

57 

1 

1 

60 

Adrenal medulla +++++++++++ 

Thyroid gland 

Pituitary gland 

Parathyroid gland 

Islets, pancreatic 

Follicular cell, adenoma 

+++++++++++ 

+++++M+++++ 

++++M++++++ 

+++++M+++++ 

61 

54 

41 

60 

2 

Tissue NOS 

General Body System 

Testes 

Seminal vesicle 

Prostate 

Preputial gland 

Penis 

Epididymis 

Genital System 

2 

+++++++++++ 

61 

61 

60 

59 

I 

61 

+ ++ 

+++++++++++ 

+++++++++++ 

+++++++++++ 

+++++++++++ 
Lesions in Male Mice 221 

0.25 mg/m3 (continued) 

Individual Animal Tumor Pathology of Male Mice in the 2-Year Inhalation Study of Nickel Sulfate Hexahydrate: 

TABLE C2 

Number of Days on Study 

8265080667922924779144441 

1282031111455566666889912 

1123445555555555555555566 

2385488162852167076065612 

0109178686203969019826308 

2221211111222111221121221 

Carcass ID Number 

Bone marrow 

Hematopoietic System ......................... 

Renal, histiocytic sarcoma 

Iliac, histiocytic sarcoma 

Histiocytic sarcoma 

Lymph node 

Spleen 

Lymph node, mediastinal 

Lymph node, mesenteric 

Lymph node, mandibular 

Lymph node, bronchial 

Histiocytic sarcoma 

Hemangiosarcoma 

Thymus 

......................... 

MMMMM+MMM+M+I+M++M++M+M++ 

+M+I+++M+++M+++++++++++++ 

++++++MM++M++++++++++++M+ 

M++M++++M++++M++++++I++++ 

X 

X 

++ + +++ 

X 

+ + ++ ++ 

+++++A+++++++++++++++++M+ 

X 

Skin 

Mammary gland 

Integumentary System 

......................... 

......................... 

Bone 

Musculoskeletal System 

......................... 

Brain 

Nervous System ......................... 

Lung 

Larynx 

Respiratory System 

X 

.......................... 

++++I++++++++++++++++++++ 

Hepatocellular carcinoma, metastatic, liver 

Alveolar/bronchiolar carcinoma, multiple 

Alveolar/bronchiolar carcinoma 

Alveolar/bronchiolar adenoma, multiple 

Alveolar/bronchiolar adenoma 

Trachea 

Nose 

......................... 

......................... 

Special Senses System 

Zymbal's gland 

Adenoma 

Harderian gland 

Urinary bladder 

Urethra 

Kidney 

Urinary System 

~ ~~ ~~ ~ 

+ 

X 

......................... Histiocytic sarcoma 

+ ++ ++ ++ 

X 

+++++++++++++++A+++++++++ 

Histiocytic sarcoma 

Multiple organs 

Systemic Lesions 

Lymphoma malignant 

Histiocytic sarcoma X 

.......................... 
222 Nickel Sulfate Hexahydrate, NTP TR 454 

TABLE C2 

0.25 mg/m3 (continued) 

Individual Animal Tumor Pathology of Male Mice in the %Year Inhalation Study of Nickel Sulfate Hexahydrate: 

0149331149401777777778888 

4444667899122333333333333 

6666666666777777777777777 

8979007343454342334985691 

6166230882287667799937778 

1211222112211111111121111 

Number of Days on Study 

Carcass ID Number 

Lymph node 

Histiocytic sarcoma 

Bone marrow 

Hematopoietic System 

......................... 

++++ + +++ + 

Renal, histiocytic sarcoma 

Iliac, histiocytic sarcoma 

Spleen 

Lymph node, mediastinal 

Lymph node, mesenteric 

Lymph node, mandibular 

Lymph node, bronchial 

Histiocytic sarcoma 

Hemangiosarcoma 

Thymus 

M++M+I +++++M++++++++++I ++ 

+++++"++++++++++++++I+++ 

......................... 

M+MI +MM+MM+M+M++++MI ++MMM 

+++++I+++++M+++++++++++M+ 

X 

++++++++++MMM++I "++++I M+ 

Skin 

Mammary gland 

Integumentary System 

......................... 

......................... 

Bone 

Musculoskeletal System 

......................... 

Brain 

Nervous System 

Lung 

Larynx 

Respiratory System 

......................... 

......................... 

......................... 

Hepatocellular carcinoma, metastatic, liver 

Alveolar/bronchiolar carcinoma, multiple 

Alveolar/bronchiolar carcinoma 

Alveolar/bronchiolar adenoma, multiple 

Alveolar/bronchiolar adenoma X X 

X X X xxx X 

X X 

......................... 

......................... X X 

Trachea 

Nose 

Special Senses System 

Zymbal's gland 

Adenoma 

Harderian gland 

Urinary bladder 

Urethra 

Kidney 

Urinary System 

X 

+ 

......................... Histiocytic sarcoma 

++ ++ ......................... Histiocytic sarcoma 

Multiple organs 

Systemic Lesions 

Lymphoma malignant 

Histiocytic sarcoma 

......................... 

X 
Lesions in Male Mice 223 

0.25 mg/m3 (continued) 

Individual Animal Tumor Pathology of Male Mice in the 2-Year Inhalation Study of Nickel Sulfate Hexahydrate: 

TABLE C2 

Number of Days on Study 

88889999999 

33333333333 

77717777777 

Carcass ID Number 

08951226824 

99027911123 

11221122222 

Tumors 

Tissues/ 

Total 

Histiocytic sarcoma 

Bone marrow 

Hematopoietic System 

Renal, histiocytic sarcoma 

Iliac, histiocytic sarcoma 

Lymph node 

Spleen 

Lymph node, mediastinal 

Lymph node, mesenteric 

Lymph node, mandibular 

Lymph node, bronchial 

Histiocytic sarcoma 

Hemangiosarcoma 

Thymus 

+++++++++++ 

+++++++++++ 

MMI I +I +MI MM 

+++++++M+++ 

++++I MM+M++ 

+I I ++++++++ 

+++M++++M++ 49 

1 

1 

61 

24 

53 

50 

49 

1 

1 

21 

1 

61 

Skin 

Mammary gland 

Integumentary System 

+++++++++++ 

+++++++++++ 

61 

61 

Bone 

Musculoskeletal System 

+++++++++++ 61 

Brain 

Nervous System +*++++++++++ 61 

Lung 

Larynx 

Respiratory System 

Hepatocellular carcinoma, metastatic, liver 

Alveolar/bronchiolar carcinoma, multiple 

Alveolar/bronchiolar carcinoma 

Alveolar/bronchiolar adenoma, multiple 

Alveolarlbronchiolar adenoma 

Trachea 

Nose 

X 

+++++++++++ 

+++++++++++ 

xx 

X 

X 

X 

+++++++++++ 

+++++++++++ 

61 

61 

2 

3 

10 

1 

4 

61 

59 

Special Senses System 

Zymbal’s gland 

Adenoma 

Harderian gland + 

X 

1 

2 

2 

Urinary bladder 

Urethra 

Kidney 

Urinary System 

Histiocytic sarcoma 

Histiocytic sarcoma 

+++++++++++ 

++ 

+++++++++++ 

1 

60 

13 

1 

61 

Multiple organs 

Systemic Lesions 

+++++++++++ 

1 

1 

61 

Lymphoma malignant 

Histiocytic sarcoma 
Nickel Sulfate Hexahydrate, NTP TR 454 

0.5 mg/m3 

Individual Animal Tumor Pathology of Male Mice in the 2-Year Inhalation Study of Nickel Sulfate Hexahydrate: 

TABLE C2 

5407495251382344811433417 

4813815881135566789911122 

2233344445555555555566666 

Number of Days on Study 

Carcass ID Number 

5335189984112579606338771 

8827529856695234574349528 

3333333333333333333333333 

Liver 

Intestine small, ileum 

Intestine small, jejunum 

Intestine small, duodenum 

Intestine large, cecum 

Intestine large, rectum 

Intestine large, colon 

Gallbladder 

Esophagus 

Alimentary System 

Histiocytic sarcoma 

Hepatocellular adenoma 

Hepatocellular carcinoma, multiple 

Hepatocellular carcinoma 

Hemangiosarcoma 

Tooth 

Stomach, glandular 

Stomach, forestomach 

Salivary glands 

Pancreas 

Mesentery 

++M++A+++++++++++++++++++ 

+"++A"+++++++++++++++++ 

+++++A+++++++++M+++++++++ 

+++++A++++M++++++M+++++++ 

+++++A+++++++++++++++++++ 

......................... 

++M++A++++++++++A++++++++ 

++M++A++++++++++A++++++++ 

++M++A++++,++++++A++++++++ 

X X xx 

xx X X 

xx 

X X 

X 

++M+++++++++++++A++++++++ 

......................... 

......................... 

I++++A+++++++++++++++++++ 

+ 

Adrenal cortex 

Endocrine System 

Heart 

Cardiovascular System 

Islets, pancreatic 

Adrenal medulla 

Capsule, adenoma 

......................... 

+++++A+++++++++++++++++++ 

X 

M+M++A+++++++++++++++++++ 

+++++A++++++++++++++++++M 

Thyroid gland 

Pituitary gland 

Parathyroid gland 

Adenoma 

Follicular cell, adenoma 

X 

+++M+++++M++++++++++I++M+ 

++++++++++M+++++++M++++++ 

X 

......................... 

Tissue NOS 

General Body System 

+ 

Epididymis 

Genital System ......................... Histiocytic sarcoma 

Testes 

Seminal vesicle 

Prostate 

Preputial gland 

Penis 

Histiocytic sarcoma 

X 

+++++A+++++++++++++++++++ 

+++++A+++++++++++M+++++++ 

+ ++++ 

......................... 

+++++A+++++++++++++++++++ 

X 
Lesions in Male Mice 225 

0.5 mg/m3 (continued) 

Individual Animal Tumor Pathology of Male Mice in the 2-Year Inhalation Study of Nickel Sulfate Hexahydrate: 

TABLE C2 

9902282692578117777188888 

2344441990012333333333333 

6666666667117777177177777 

3024648665043148452497806 

9842718299395233457834456 

3333333333333333333333333 

Number of Days on Study 

Carcass ID Number 

Liver 

Intestine small, ileum 

Intestine small, jejunum 

Intestine small, duodenum 

Intestine large, cecum 

Intestine large, rectum 

Intestine large, colon 

Gallbladder 

Esophagus 

Alimentary System 

Histiocytic sarcoma 

Hepatocellular adenoma 

Hepatocellular carcinoma, multiple 

Hepatocellular carcinoma 

Hemangiosarcoma 

Tooth 

Stomach, glandular 

Stomach, forestomach 

Salivary glands 

Pancreas 

Mesentely 

......................... 

+++++++++++++M+++++++++++ 

......................... 

......................... 

......................... 

+++++I I ++++++I ++++++++M++ 

......................... 

++++++++++++++++I ++++I ++M 

......................... 

X 

xx X X X 

x xx x X xx 

......................... 

......................... 

......................... 

......................... 

+ + 

Heart 

Cardiovascular System 

......................... 

Adrenal cortex 

Endocrine System 

Islets, pancreatic 

Adrenal medulla 

Capsule, adenoma 

Thyroid gland 

Pituitaly gland 

Parathyroid gland 

Adenoma 

Follicular cell, adenoma 

......................... X 

++++++++++M+++++I++++++++ 

++++++++++++++I++++++++++ 

MM+M+++++M++++++++++I++++ 

......................... 

........................ 

Tissue NOS 

General Body System 

Epididymis 

Genital System 

Testes 

Seminal vesicle 

Prostate 

Preputial gland 

Penis 

Histiocytic sarcoma 

Histiocytic sarcoma 

......................... X 

......................... 

......................... 

......................... 

......................... 

++ + +I 
226 Nickel Sulfate Hexahydrate, NTP TR 454 

TABLE C2 

0.5 mg/m3 (continued) 

Individual Animal Tumor Pathology of Male Mice in the 2-Year Inhalation Study of Nickel Sulfate Hexahydrate: 

888899999999 

333333333333 

777777777777 

793721019576 

667823445678 

333333333333 

Number of Days on Study 

Tumors 

Tissues/ 

Total 

Carcass ID Number 

Intestine small, duodenum 

Intestine large, cecum 

Intestine large, rectum 

Intestine large, colon 

Gallbladder 

Esophagus 

Alimentary System 

++++++++++++ 

++++++++++++ 

+I +++++I I +++ 

++++++++++++ 

++++++++++++ 

+.+++++++++++ 

59 

60 

50 

60 

56 

61 

Intestine small, jejunum ++++++++++++ 59 

Intestine small, ileum 

Tooth 

Stomach, glandular 

Stomach, forestomach 

Salivary glands 

Pancreas 

Mesentery 

Histiocytic sarcoma 

Hepatocellular adenoma 

Hepatocellular carcinoma, multiple 

Hepatocellular carcinoma 

Hemangiosarcoma 

Liver ++++++++++++ 

++++++++M+++ 

X 

X xx 

X 

xx x x X 

++++++++++++ 

++++++++++++ 

++++++++++++ 

++++++++++++ 

+ 

+ 4 

60 

62 

62 

60 

1 

1 

18 

3 

12 

2 

62 

57 

Heart 

Cardiovascular System 

++++++++++++ 62 

Adrenal cortex 

Endocrine System 

Islets, pancreatic 

Adrenal medulla 

Capsule, adenoma 

Thyroid gland 

Pituitary gland 

Parathyroid gland 

Adenoma 

Follicular cell, adenoma 

++++++++++++ 

X 

++++++++++++ 

++++++++++++ 

++++++++++++ 

++++++++++++ 

M++++++++I ++ 

61 

58 

51 

1 

57 

59 

3 

61 

1 

Tissue NOS 

General Body System 

1 

~~ 

Epididymis 

Genital System 

Testes 

Seminal vesicle 

Prostate 

Preputial gland 

Penis 

Histiocytic sarcoma 

++++++++++++ 

++++++++++++ 

++++++++++++ 

++++++++++++ 

++++++++++++ 

62 

61 

61 

60 

9 

2 

62 

Histiocytic sarcoma 1 
Lesions in Male Mice 227 

TABLE C2 

0.5 mg/m3 (continued) 

Individual Animal Tumor Pathology of Male Mice in the 2-Year Inhalation Study of Nickel Sulfate Hexahydrate: 

Number of Days on Study 

5407495251382344811433417 

4813815881135566789911122 

2233344445555555555566666 

Carcass ID Number 

5335189984112579606338771 

8827529856695234574349528 

3333333333333333333333333 

Lymph node, bronchial 

Lymph node 

Bone marrow 

Hematopoietic System 

Thymus 

Spleen 

Lymph node, mediastinal 

Lymph node, mesenteric 

Lymph node, mandibular 

Histiocytic sarcoma 

MI M+MA+M++I ++M+I +++I +M+++ 

++ 

+++++A+++++++++++++++++++ 

+ ++ ++ + 

X 

M++++A+M++++M++++++++++++ 

+++++A+++++++++++++++++++ 

MMMMMAM+MI ++"I +M++M+MMI M 

++M++A++++++++++A++++++++ 

++M++M+++++++++++++++++++ 

Skin 

Mammary gland 

Integumentary System 

......................... 

+++++M+++++++++++++++++++ 

Bone 

Musculoskeletal System 

......................... 

Brain 

Nervous System 

......................... 

Lung 

Larynx 

Respiratory System 

X 

......................... 

+++++A+I+++++++++++++++++ 

Hepatocellular carcinoma, metastatic, liver 

Alveolar/hronchiolar carcinoma, multiple 

Alveolar/bronchiolar carcinoma 

Alveolar/hronchiolar adenoma 

X 

X X 

Trachea 

Nose 

+++++A+++++++++++++++,+++ 

+++++A+++++++++++++++++++ 

Harderian gland 

EY e 

Special Senses System 

Adenoma X 

+ 

Urinary bladder 

Urethra 

Ureter 

Kidney 

Urinary System 

Multiple organs 

Systemic Lesions 

+++++A+++++++++++++++++++ 

+ 

+ 

+++++A+++++++++++++++++++ 

++ + + 

......................... 

Lymphoma malignant 

Histiocytic sarcoma X 
228 Nickel Sulfate Hexahydrate, NTP TR 454 

TABLE C2 

0.5 mgh3 (continued) 

Individual Animal Tumor Pathology of Male Mice in the 2-Year Inhalation Study of Nickel Sulfate Hexahydrate: 

2344447990012333333333333 

6666666667777777777777777 

Number of Days on Study 

9902282692578777177788888 

3333333333333333333333333 

Carcass ID Number 

3024648665043148452497806 

9842778299395233457834456 

Lymph node, bronchial 

Lymph node 

Bone marrow 

Hematopoietic System 

Histiocytic sarcoma 

+M+I++MM+M+++++++++++++++ 

+++ +++ + ......................... + 

Thymus 

Spleen 

Lymph node, mediastinal 

Lymph node, mesenteric 

Lymph node, mandibular 

++M++++++++++++++M+++++M+ 

......................... 

++M+MMM+MMM+I+M+MMM+M++MM 

+++M++M++++++++++++++++++ 

+++++M++++++++M+++++++M++ 

Skin 

Mammary gland 

Integumentary System 

......................... 

......................... 

Bone 

Musculoskeletal System 

......................... 

Brain 

Nervous System 

......................... 

Lung 

Larynx 

Respiratory System 

......................... 

++++++++++++++++++++I+M++ 

Hepatocellular carcinoma, metastatic, liver 

Alveolar/bronchiolar carcinoma, multiple 

Alveolar/bronchiolar carcinoma 

Alveolar/bronchiolar adenoma X 

X X 

X 

X 

Trachea 

Nose 

......................... 

......................... 

Harderian gland 

EY e 

Special Senses System 

Adenoma 

Urinary bladder 

Urethra 

Ureter 

Kidney 

Urinary System 

~~~ ~~ 

.......................... 

+ + ++++ ++ + ......................... 

Multiple organs 

Systemic Lesions 

X 

......................... 

Lymphoma malignant 

Histiocytic sarcoma X 
Lesions in Male Mice 229 

0.5 mgh' (continued) 

Individual Animal Tumor Pathology of Male Mice in the 2-Year Inhalation Study of Nickel Sulfate Hexahydrate: 

TABLE C2 

Number of Days on Study 

888899999999 

333333333333 

777777777777 

193721019576 

667823445678 

333333333333 

Tumors 

Tissues/ 

Total 

Carcass ID Number 

Lymph node, bronchial 

Lymph node 

Bone marrow 

Hematopoietic System 

++++++++++++ 

45 

20 

61 

++ + + 

++++++++M+++ 

Thymus 

Spleen 

Lymph node, mediastinal 

Lymph node, mesenteric 

Lymph node, mandibular 

Histiocytic sarcoma 

+++M+++++M++ 

++++++++++++ 

"++"MI MMM+ 

++++++++++++ 

++++++++++++ 

53 

61 

20 

57 

57 

1 

Skin 

Mammary gland 

Integumentary System 

++++++++++++ 

++++++++++++ 

62 

61 

Bone 

Musculoskeletal System 

++++++++++++ 62 

Brain 

Nervous System 

++++++++++++ 62 

Lung 

Larynx 

Respiratory System 

++++++++++++ 

++++++++++++ 

61 

61 

3 

1 

3 

3 

62 

58 

Hepatocellular carcinoma, metastatic, liver 

Alveolar/bronchiolar carcinoma, multiple 

Alveolarlbronchiolar carcinoma 

Alveolar/bronchiolar adenoma X 

Trachea 

Nose 

Harderian gland 

EY e 

Special Senses System 

Adenoma 

++++++++++++ 

++++++++++++ 

X 

+ 

+ 

2 

2 

1 

Urinary bladder 

Urethra 

Ureter 

Kidney 

Urinary System 

++++++++++++ 

60 

15 

1 

61 

++++++++M+++ 

+ 

Multiple organs 

Systemic Lesions 

Lymphoma malignant 

Histiocytic sarcoma 

++++++++++++ 

X X 3 

2 

62 
230 Nickel Sulfate Hexahydrate, NTP TR 454 

9844783933180247713401080 

6290450233667799900012334 

1334445555555555566666666 

2062811794382123315060045 

9654313345001038482322518 

4555555555555554545555554 

Number of Days on Study 

Carcass ID Number 

Liver 

Intestine small, ileum 

Intestine small, jejunum 

Intestine small, duodenum 

Intestine large, cecum 

Intestine large, rectum 

Intestine large, colon 

Gallbladder 

Esophagus 

Alimentary System 

Hepatocellular adenoma 

Hepatocellular carcinoma, multiple 

Hepatocellular carcinoma 

Tooth 

Stomach, glandular 

Stomach, forestomach 

Salivary glands 

Pharynx 

Pancreas 

Mesentery 

++++A+++++A++++++++++++++ 

++++A++++AA++++++++++++A+ 

++++A+++++A++++++++++++A+ 

++++A++++MA++++++++++++A+ 

++++A++++MA++++++++++++A+ 

+++IA+++++A++++++M++++MA+ 

++++A+++++A++++++++++++A+ 

++++A++A+M+++M++++AA+++++ 

......................... 

xx X 

X X X X xx 

+ 

++++A+++I+A++++++++++++++ 

++++A+++++A++++++++++++++ 

++++A+++++A++++++++++++++ 

++++A++++++++++++++++++++ 

Heart 

Cardiovascular System 

++++A++++++++++++++++++++ 

Adrenal cortex 

Endocrine System 

Thyroid gland 

Pituitary gland 

Parathyroid gland 

Islets, pancreatic 

Adrenal medulla 

Capsule, adenoma 

Follicular cell, adenoma 

++++A+++++A++++++++++++++ 

......................... 

++++A++++++++++++++++++++ 

M+++++++++M++M++M++I+M+++ 

++++A+++M+A++++M+++++++++ 

++++A+++++A++++++++M+++++ 

None 

General Body System 

Testes 

Seminal vesicle 

Prostate 

Preputial gland 

Penis 

Epididymis 

Genital System 

++++++M++++++++++++++++++ 

++++A++++++++++++++++++++ 

++++++M++++++++++++++++++ 

+ ++++ ++ + 

++++++M++++++++++++++++++ 

++++++M++++++++++++++++++ 
Lesions in Male Mice 231 

1 mg/m3 (continued) 

Individual Animal Tumor Pathology of Male Mice in the 2-Year Inhalation Study of Nickel Sulfate Hexahydrate: 

TABLE C2 

Number of Days on Study 

1175566999907777177777888 

4457777799023333333333333 

6666666666777777777777777 

Carcass ID Number 

36345.55094074860679678479 

2433391114928890000112999 

5555545555454445555555444 

Intestine small, duodenum 

Intestine large, cecum 

Intestine large, rectum 

Intestine large, colon 

Gallbladder 

Esophagus 

Alimentary System 

+M++++++++M++++++++++++++ 

......................... 

......................... 

......................... 

+++++++++++M++++M++++++++ 

+++++++++++++++++++I+++++ 

Liver 

Intestine small, ileum 

Intestine small, jejunum 

......................... 

+++++M+++++++++++++++++++ 

......................... 

Hepatocellular adenoma 

Hepatocellular carcinoma, multiple 

Hepatocellular carcinoma xx x X 

X 

X 

X X 

Tooth 

Stomach, glandular 

Stomach, forestomach 

Salivary glands 

Pharynx 

Pancreas 

Mesentery 

......................... + 

......................... 

......................... 

......................... 

+ 

Adrenal medulla 

Capsule, adenoma 

Adrenal cortex 

Endocrine System 

Heart 

Cardiovascular System 

......................... 

......................... 

+++++++++++M+++++++++++++ 

Thyroid gland 

Pituitary gland 

Parathyroid gland 

Islets, pancreatic 

Follicular cell, adenoma 

......................... 

+++M+++++M+++++++++++++M+ 

++M+MM+I ++M++++MI ++M++M++ 

......................... 

X 

None 

General Body System 

Prostate 

Preputial gland 

Penis 

Epididymis 

Genital System 

......................... ++ + ++ 

......................... 

......................... 

Testes 

Seminal vesicle 

......................... 

......................... 
232 Nickel Sulfate Hexahydrate, NTP TR 454 

1 mgh3 (continued) 

Individual Animal Tumor Pathology of Male Mice in the 2-Year Inhalation Study of Nickel Sulfate Hexahydrate: 

TABLE C2 

888889999999 

333333333333 

777777777777 

Number of Days on Study 

Carcass ID Number 

431489957139 

012252344555 

555555555555 

Tumors 

Tissues/ 

Total 

Intestine large, rectum 

Intestine large, colon 

Gallbladder 

Esophagus 

Alimentary System 

I I ++I ++I I +I + 

++++++++++++ 

++++++++++++ 

++++++++++++ 

50 

59 

54 

61 

Liver 

Intestine small, ileum 

Intestine small, jejunum 

Intestine small, duodenum 

Intestine large, cecum 

Hepatocellular adenoma 

Hepatocellular carcinoma, multiple 

Hepatocellular carcinoma 

Tooth 

Stomach, glandular 

Stomach, forestomach 

Salivary glands 

Pharynx 

Pancreas 

Mesentery 

++++++++++++ 

+++M++++++++ 

++++++++++++ 

++++++++++++ 

++++++++++++ 

X 

X 

X 

++++++++++++ 

+ 

++++++++++++ 

++++++++++++ 

++++++++++++ 

+ 2 

60 

60 

61 

2 

59 

1 

10 

2 

8 

60 

56 

59 

56 

58 

Adrenal cortex 

Endocrine System 

Heart 

Cardiovascular System 

Thyroid gland 

Pituitary gland 

Parathyroid gland 

Islets, pancreatic 

Adrenal medulla 

Capsule, adenoma 

++++++++++++ 61 

++++++++++++ 

1 

62 

58 

45 

58 

58 

1 

60 

++++++++++++ 

++++++++++++ 

++M+++++M+++ 

++++++++++++ 

++++++++++++ 

Follicular cell, adenoma 

None 

General Body System 

~~ ~~ 

Testes 

Seminal vesicle 

Prostate 

Preputial gland 

Penis 

Epididymis 

Genital System 

~~ 

++++++++++++ 

++++++++++++ 

++++++++++++ 

++++++++++++ 

+++++++++M++ 

61 

61 

61 

60 

13 

61 
Lesions in Male Mice 233 

1 mg/m3 (continued) 

Individual Animal Tumor Pathology of Male Mice in the 2-Year Inhalation Study of Nickel Sulfate Hexahydrate: 

TABLE C2 

Number of Days on Study 

9844783933180247713401080 

6290450233667799900012334 

1334445555555555566666666 

2062811794382123315060045 

9654313345001038482322518 

4555555555555554545555554 

Carcass ID Number 

Thymus 

Spleen 

Lymph node, mediastinal 

Lymph node, mesenteric 

Lymph node, mandibular 

Lymph node, bronchial 

Lymph node 

Bone marrow 

Hematopoietic System 

Skin 

Mammary gland 

Integumentary System 

+I++A++++MAM++++++++++M+M 

++++A+++++A++++++++++++++ 

+MMMMMMMM++MI +"+MI +MMM+M 

++++A+++++A+++M+++M++++++ 

MMM+A+++M+M++I+++M+M++++M 

+I++A+++M+++++M++++++M+++ 

++ +++ + ++++++ + ++ ++ 

++++A++++++++++++++++++++ 

++++A++++++++++++++++++++ 

++++A++++++++++++++++++++ 

Bone 

Musculoskeletal System 

......................... 

Brain 

Nervous System 

Lung 

Larynx 

Respiratory System 

......................... 

++++A++++++++++++++++++++ 

......................... 

Hepatocellular carcinoma, metastatic, liver 

Alveolarlbronchiolar carcinoma 

Alveolar/bronchiolar adenoma, multiple 

Alveolar/bronchiolar adenoma X 

X 

X 

Adenoma 

Harderian gland 

Special Senses System 

Trachea 

Nose 

++++++++++A++++++++++++++ 

++++A+++++A++++++++++++++ 

Urinary bladder 

Urethra 

Ureter 

Kidney 

Urinary System 

++++A+M+++A++++++++++++++ 

++ + ++ 

+ 

++++++'++++A++++++++++++++ 

+ 

+ + ++ 

Multiple organs 

Systemic Lesions 

.......................... 
234 Nickel Sulfate Hexahydrate, NTP TR 454 

TABLE C2 

1 mg/m3 (continued) 

Individual Animal Tumor Pathology of Male Mice in the 2-Year Inhalation Study of Nickel Sulfate Hexahydrate: 

1175566999907777777777888 

4457771799023333333333333 

6666666666777777777777777 

3634555094074860679678479 

2433391114928890000112999 

5555545555454445555555444 

Number of Days on Study 

Carcass ID Number 

Thymus 

Spleen 

Lymph node, mediastinal 

Lymph node, mesenteric 

Lymph node, mandibular 

Lymph node, bronchial 

Lymph node 

Bone marrow 

Hematopoietic System 

I++++++M++++++++M++++++++ 

+I+++++++++++++++MM+++M++ 

+M+M++++++++++++++++I++++ 

+ +++ ++ ......................... + 

++M++++MMM++++++M++++++M+ 

......................... 

++"+I ++"I +M+++++MMMI M+M 

Skin 

Mammary gland 

Integumentary System 

......................... 

......................... 

Brain 

Nervous System 

Bone 

Musculoskeletal System 

......................... 

......................... 

Lung 

Larynx 

Respiratory System 

......................... 

......................... 

Hepatocellular carcinoma, metastatic, liver 

Alveolar/bronchiolar carcinoma 

Alveoladbronchiolar adenoma, multiple 

Alveolar/bronchiolar adenoma X 

X 

X X 

Trachea 

Nose 

......................... 

......................... 

Adenoma 

Harderian gland 

Special Senses System 

X 

+ 

Urinary bladder 

Urethra 

Ureter 

Kidney 

Urinary System 

......................... 

++++ + + ......................... 

Multiple organs 

Systemic Lesions 

......................... 
Lesions in Male Mice 235 

1 mg/m3 (continued) 

Individual Animal Tumor Pathology of Male Mice in the 2-Year Inhalation Study of Nickel Sulfate Hexahydrate: 

TABLE C2 

I71177777717 

Number of Days on Study 

888889999999 

333333333333 

Carcass ID Number 

431489957139 

012252344555 

555555555555 

Tumors 

Tissues/ 

Total 

Thymus 

Spleen 

Lymph node, mediastinal 

Lymph node, mesenteric 

Lymph node, mandibular 

Lymph node, bronchial 

Lymph node 

Bone marrow 

Hematopoietic System 

+++M++++++++ 

+++M+++M+M++ 

++++++++++++ 

++ 

++++++++++++ 

I ++++M+++MM+ 

++++++++++++ 

MMMMM+M+++I M 

45 

60 

23 

54 

45 

54 

26 

61 

Skin 

Mammary gland 

Integumentary System 

++++++++++++ 

++++++++++++ 

61 

61 

Bone 

Musculoskeletal System ________~~ ~ ______~ ____~~ 

++++++++++++ 62 

Brain 

Nervous System _____~ 

62 

Lung 

Larynx 

Respiratory System 

++++++++++++ 

++++++++++++ 

1 

4 

61 

62 

Alveolar/bronchiolar adenoma, multiple 

Alveolarlbronchiolar adenoma xx 

Hepatocellular carcinoma, metastatic, liver 

Alveolar/bronchiolar carcinoma 

++++++++++++ 

++++++++++++ 

X 

Trachea 

Nose 

61 

60 

2 

3 

Adenoma 

Harderian gland 

Special Senses System 

1 

1 

Urinary bladder 

Urethra 

Ureter 

Kidney 

Urinary System 

++++++++++++ 

59 

16 

2 

61 

+ 

++++++++++++ 

Multiple organs 

Systemic Lesions 

++++++++++++ 62 
Nickel Sulfate Hexahydrate, NTP TR 454 

Statistical Analysis of Primary Neoplasms in Male Mice in the 2-Year Inhalation Study of Nickel Sulfate Hexahydrate 

TABLE C3 

O mg/m3 0.25 mg/m’ 0.5 mg/m’ 1 mg/m3 

Fisher exact test 

Cochran-Amita e testd 

Logistic regression testd 

Life table testd 

First incidence (days) 

Terminal rate’ 

Adjusted rateb 

Overall ratea 

Adrenal Cortex: Adenoma 

Fisher exact test 

Cochran-Armitage test 

Logistic regression test 

Life table test 

First incidence (days) 

Terminal rate 

Adjusted rate 

Overall rate 

Liver: Hepatocellular Adenoma 

Fisher exact test 

Cochran-Amitage test 

Logistic regression test 

Life table test 

First incidence (days) 

Terminal rate 

Adjusted rate 

Overall rate 

Liver: Hepatocellular Carcinoma 

Fisher exact test 

Cochran-Armitage test 

Logistic regression test 

Life table test 

First incidence (days) 

Terminal rate 

Adjusted rate 

Overall rate 

Liver: Hepatocellular Adenoma or Carcinoma 

Fisher exact test 

Cochran-Armitage test 

Logistic regression test 

Life table test 

First incidence (days) 

Terminal rate 

Adjusted rate 

Overall rate 

Lung: Alveolar/bronchiolar Adenoma 

i P=O.552 

P=O.556 

P=O.577 

737 (T) 

1/26 (4%) 

3.8% 

1/61 (2%) 

P=0.190N 

P=0.186N 

P=0.176N 

395 

9/26 (35%) 

47.2 % 

18/61 (30%) 

P=0.506N 

P=0.538N 

P=0.461N 

452 

2/26 (8 %) 

24.4% 

11/61 (18%) 

P=0.210N 

P=0.220N 

P=0.201N 

395 

11\26 (42 %) 

60.3% 

27/61 (44%) 

P=0.532N 

P=0.509N 

P=0.525N 

688 

4/26 (15%) 

18.4% 

5/61 (8%) 

P=O.756 

P=O.733 

552 

0122 (0%) 

2.0% 

1/60 (2 %) 

P=O.748 

P=0.014N 

P=0.030N 

517 

0/23 (0%) 

17.4% 

7/61 (11%) 

P=0.012N 

P=0.590N 

P=O.498 

552 

3/23 (13%) 

31.8% 

11/61 (18%) 

P=0.593N 

P=0.071N 

P=0.168N 

517 

3/23 (13%) 

43.6% 

18/61 (30%) 

P=0.066N 

P=O.606 

P=O.574 

552 

3/23 (13%) 

17.2% 

5/61 (8%) 

P=0.628N 

P=O.299 

P=O.306 

62 1 

1/24 (4%) 

9.6% 

3/61 (5%) 

P=O.309 

P=0.577N 

P=O.510 

284 

8/24 (33 %) 

48.9% 

18/62 (29%) 

P=0.556N 

P=O.211 

P=O.235 

482 

6/24 (25 X) 

39.7% 

15/62 (24%) 

P=O.269 

P=O.451 

P=O.365 

284 

12/24 (50%) 

67.4% 

29/62 (47%) 

P=O.461 

P=0.363N 

P=0.384N 

552 

1/24 (4%) 

9.1% 

3/62 (5%) 

P=0.350N 

P=O.761 

P=0.757N 

60 1 

012.5 (0%) 

2.2% 

1/60 (2%) 

P=O.748 

P=0.072N 

P=0.079N 

404 

3/25 (12%) 

25.3% 

10160 (17%) 

P=0.072N 

P=0.522N 

P=0.478N 

533 

3/25 (12%) 

26.9% 

10160 (17%) 

P=0.517N 

P=0.108N 

P=0.125N 

404 

6/25 (24%) 

44.7% 

19/60 (32%) 

P=0.107N 

P=0.614N 

P=O.615 

597 

3/25 (12%) 

17.2% 

5/61 (8%) 

P=0.628N 
Lesions in Male Mice 237 

(continued) 

Statistical Analysis of Primary Neoplasms in Male Mice in the 2-Year Inhalation Study of Nickel Sulfate Hexahydrate 

TABLE C3 

O mg/m3 0.25 mg/m3 0.5 mg/m3 1 mg/m3 

Fisher exact test 

Cochran-Armitage test 

Logistic regression test 

Life table test 

First incidence (days) 

Terminal rate 

Adjusted rate 

Overall rate 

Lung: Alveolarhronchiolar Carcinoma 

Fisher exact test 

Cochran-Armitage test 

Logistic regression test 

Life table test 

First incidence (days) 

Terminal rate 

Adjusted rate 

Overall rate 

Lung: Alveolarhronchiolar Adenoma or 

Fisher exact test 

Cochran-Annitage test 

Logistic regression test 

Life table test 

First incidence (days) 

Terminal rate 

Adjusted rate 

Overall rate 

All Organs: Malignant Lymphoma 

Fisher exact test 

Cochran-Armitage test 

Logistic regression test 

Life table test 

First incidence (days) 

Terminal rate 

Adjusted rate 

Overall rate 

All Organs: Benign Neoplasms 

Fisher exact test 

Cochran-Armitage test 

Logistic regression test 

Life table test 

First incidence (days) 

Terminal rate 

Adjusted rate 

Overall rate 

All Organs: Malignant Neoplasms 

P=0.012N 

P=0.009N 

P=0.012N 

516 

6/26 (23 %) 

29.5% 

9/61 (15%) 

Carcinoma 

P=0.042N 

P=0.029N 

P=0.040N 

516 

10126 (38%) 

43.6% 

13/61 (21%) 

P=0.237N 

P=0.233N 

P=0.248N 

737 (T) 

2/26 (8%) 

7.7% 

2/61 (3%) 

P=0.144N 

P=0.138N 

P=0.165N 

395 

12/26 (46%) 

59.9% 

24/61 (39%) 

48.9% 

20/61 (33 %) 

P=0.073N 

P=0.065N 

P=0.095N 

452 

8/26 (31 xj 

P=O.191 

P=O.155 

687 

11/23 (48%) 

51.6% 

13/61 (21%) 

P=O.240 

P=O.144 

P=O.l05 

552 

14/23 (61 %) 

65.4% 

18/61 (30%) 

P=O.203 

P=0.516N 

P=0.528N 

687 

0123 (0%) 

3.4% 

1/61 (2%) 

P=0.500N 

P=O.lOlN 

P=0.177N 

5 17 

5/23 (22%) 

41.8% 

16/61 (26%) 

P=0.088N 

P=O.368 

P=O.302 

552 

13/23 (57%) 

66.8% 

22/61 (36%) 

P=O.425 

P=0.122N 

P=0.138N 

613 

2/24 (8%) 

13.0% 

4/62 (6%) 

P=0.114N 

P=O. 11 1N 

P=0.135N 

552 

3/24 (13%) 

21.2% 

7/62 (1 1 %) 

P=0.103N 

P=O.480 

P=O.464 

728 

2/24 (8 %) 

12.0% 

3/62 (5 X) 

P=O.508 

P=O.503 

P=O.445 

284 

10124 (42%) 

60.5 46 

25/62 (40%) 

P=O.529 

P=O.222 

P=O.205 

482 

12/24 (50%) 

64.1 x 

25/62 (40%) 

P=O.248 

P=0.057N 

P=0.068N 

561 

2/25 (8%) 

9.8% 

3/61 (5%) 

P=0.063N 

P=0.142N 

P=O. 179N 

561 

5/25 (20%) 

26.2% 

8/61 (13%) 

P=0.169N 

0125 (0%) 

0.0% 

0162 (0%) 

P=0.246N 

P=0.246N 

- 

e 

P=0.244N 

P=0.078N 

P=O.lllN 

404 

7/25 (28%) 

42.5% 

16/62 (26%) 

P=0.079N 

P=O.lOON 

P=0.129N 

533 

5/25 (20%) 

34.8% 

13/62 (21%) 

P=O. lOlN 
238 Nickel Sulfate Hexahydrate, NTP TR 454 

(continued) 

Statistical Analysis of Primary Neoplasms in Male Mice in the 2-Year Inhalation Study of Nickel Sulfate Hexahydrate 

TABLE C3 

O mg/mJ 0.25 mg/m3 0.5 mg/m’ 1 mg/m3 

Fisher exact test 

Cochran-Armitage test 

Logistic regression test 

Life table test 

First incidence (days) 

Terminal rate 

Adjusted rate 

Overall rate 

All Organs: Benign or Malignant Neoplasms 

P=0.019N 

P=0.015N P=0.368N P=O.349 P=0.017N 

P=0.053N P=0.515N P=O.318 P=0.054N 

395 517 284 

19/26 (73 %) 17/23 (74%) 16/24 (67%) 11/25 (44%) 

83.8% 84.3% 82.9% 

39/61 (64%) 35/61 (57%) 42/62 (68%) 27/62 (44%) 

62.4% 

P=0.289N P=O.399 P=0.018N 

(T)Terminal sacrifice 

Not applicable; no neoplasms in animal group 

compare directly the overall incidence rates. For all tests, a negative trend .or a lower incidence in an exposure group is indicated by N. 

(directly or indirectly) the cause of death. The logistic regression test regards these lesions as nonfatal. The Cochran-Armitage and Fisher exact tests 

pairwise comparisons between the controls and that exposed group. The life table test regards neoplasms in animals dying prior to terminal kill as being 

Beneath the control incidence are the P values associated with the trend test. Beneath the exposed group incidence are the P values corresponding to 

Observed incidence at terminal kill 

Kaplan-Meier estimated neoplasm incidence at the end of the study after adjustment for intercurrent mortality 

and lung; for other tissues, denominator is number of animals necropsied. 

Number of neoplasm-bearing animalslnumber of animals examined. Denominator is number of animals examined microscopically for adrenal gland, liver, 
Lesions in Male Mice 239 

Historical Incidence of Alveolar/bronchiolar Neoplasms in Untreated Male B6C3F, Micea 

TABLE C4a 

Study Carcinoma 

Incidence in Controls 

Adenoma Adenoma or Carcinoma 

Historical Incidence at Lovelace Inhalation Toxicology Research Institute 

Talc 

Nickel Sulfate Hexahydrate 

Nickel Subsulfide 

Nickel Oxide 

6/45 

5/61 

6/61 

7/57 

Overall Historical Incidence in Inhalation Studies 

Range 

Standard deviation 

Total 

6%-36% 

7.0% 

141/952 (14.8%) 

Overall Historical Incidence in Feed Studies 

Range 

Standard deviation 

Total 

4%-28% 

6.4% 

194/1,319 (14.7%) 

7/45 

9/61 

7/61 

4/57 

0%-16% 

5.7% 

75/952 (7.9%) 

0%-14% 

3.9% 

64/1,319 (4.9%) 

12/45 

13/61 

13/61 

9/57 

10%-42% 

8.0% 

205/952 (21.5 %) 

4%-32% 

1.6% 

249/1,319 (18.9%) 

a Data as of 17 March 1994 
240 Nickel Sulfate Hexahydrate, NTP TR 454 

Historical Incidence of Hepatocellular Neoplasms in Untreated Male B6C3Fl Micea 

TABLE C4b 

Study Carcinoma 

Incidence in Controls 

Adenoma Adenoma or Carcinoma 

Historical Incidence at Lovelace Inhalation Toxicology Research Institute 

Talc 

Nickel Sulfate Hexahydrate 

Nickel Subsulfide 

Nickel Oxide 

3/45 

18/61 

13/61 

8/57 

Overall Historical Incidence in Inhalation Studies 

Range 

Standard deviation 

Total 

4%46% 

11.7% 

201/952 (21.1%) 

6/45 

11/61 

11/61 

6/57 

9%-29% 

5.8% 

185/952 (19.4%) 

9/45 

2716 1 

24/6 1 

12/57 

11%-60% 

12.6% 

360/952 (37.8%) 

Overall Historical Incidence in Feed Studies 

Range 

Standard deviation 

Total 

13.2% 

34411,316 (26.1%) 

7.2% 

22011,316 (16.7%) 

13.9% 

509/1,316 (38.7%) 

4%-60% 3%-29% 10%-68% 

a Data as of 17 June 1994 
Lesions in Male Mice 241 

of Nickel Sulfate Hexahydratea 

Summary of the Incidence of Nonneoplastic Lesions in Male Mice in the 2-Year Inhalation Study 

TABLE C5 

O mg/mg 0.25 mg/m3 0.5 mg/m3 1 mg/m3 

Early deaths 

IS-Month interim evaluation 

FMonth interim evaluation 

Animals initially in Study 

Disposition Summary 

Terminal sacrifice 

Natural deaths 

Moribund 

Survivors 

5 

5 

71 

5 

30 

26 

5 

5 

71 

9 

29 

23 

5 

5 

72 

9 

29 

24 

5 

5 

72 

10 

27 

25 

Animals examined microscopically 71 71 I2 12 

Liver 

Alimentary System 

7-Month Interim Evaluation 

Hepatocyte, hyperplasia 

Preputial gland 

Genital System 

Ectasia 

Hyperplasia, lymphoid 

Lymph node, bronchial 

Hematopoietic System 

Hyperplasia, lymphoid 

Lymph node, mediastinal 

Lung 

Respiratory System 

Interstitium, infiltration cellular 

Inflammation, acute 

Hyperplasia, macrophage 

Olfactory epithelium, atrophy 

Inflammation, acute 

Nose 

(5) (5) (5) (5) 

1 (20%) 

1 (20%) 

5 (100%) 

1 (20%) 

(5) (5) (51 (5) 

1 (20%) 2 (40%) 1 (20%) 

2 (40%) 

2 (40%) 

Urinary System 

Special Senses System 

Nervous System 

Musculoskeletal System 

Integumentary System 

General Body System 

Endocrine System 

Cardiovascular System 

Systems Examined With No Lesions Observed 

a Number of animals examined microscopicalIy at the site and the number of animals with lesion 
242 Nickel Sulfate Hexahydrate, NTP TR 454 

Of Nickel Sulfate Hexahydrate (continued) 

Summary Of the Incidence of Nonneoplastic Lesions in Male Mice in the 2-Year Inhalation Study 

TABLE C5 

0 mg/m3 0.25 mg/m3 0.5 mg/mg 1 mg/m3 

Liver 

Alimentary System 

15-Month Interim Evaluation 

Hepatocyte, hyperplasia 

Infarct, focal 

(5) 

1 (20%) 

(5) 

1 (20%) 

Thyroid gland 

Endocrine System 

Follicular cell, hyperplasia, focal 

(5) 

1 (20%) 

Genital System 

Inflammation 

Ectasia 

Preputial gland (5) (5) (5) (5) 

2 (40%) 

5 (100%) 

2 (40%) 

5 (100%) 5 (100%) 

3 (60%) 

5 (100%) 

Lymph node 

Hematopoietic System 

Renal, hyperplasia, lymphoid 

Lumbar, hyperplasia, lymphoid 

Inguinal, thrombosis 

Inguinal, hyperplasia, lymphoid 

Iliac, inflammation 

Iliac, hyperplasia, lymphoid 

Inflammation 

Lymph node, mandibular 

Hyperplasia, macrophage 

Hyperplasia, lymphoid 

Lymph node, bronchial 

(1) 

1 (100%) 

1 (100%) 

(4) (5) 

1 (25%) 

1 (25%) 3 (60%) 

(4) (5) 

1 (20%) 

(2) (2) 

2 (100%) 

1 (50%) 

1 (50%) 

1 (50%) 

2 (100%) 

1 (50%) 

1 (50%) 

(5) (5) 

1 (20%) 

4 (80%) 

(5) (4) 

Integumentary System 

Subcutaneous tissue, inflammation 

Dermis, inflammation, chronic active 

Ulcer, chronic active 

Skin (5) (5) 

1 (20%) 

(5) (5) 

1 (20%) 

1 (20%) 

Lung 

Larynx 

Respiratory System 

Inflammation 

Interstitium, inflammation, focal 

Interstitium, infiltration cellular 

Alveolus, proteinosis 

Alveolar epithelial hyperplasia, focal 

Bronchialization 

Inflammation, chronic active 

Hyperplasia, macrophage 

(5) 

(5) 

(5) 

(5) 

(5) 

(4) 

(5) 

(3) 

1 (20%) 

1 (20%) 

1 (20%) 4 (80%) 

5 (100%) 

4 (80%) 

5 (100%) 

3 (60%) 

1 (20%) 

5 (100%) 

1 (20%) 
Lesions in Male Mice 243 

of Nickel Sulfate Hexahydrate (continued) 

Summary of the Incidence of Nonneoplastic Lesions in Male Mice in the 2-Year Inhalation Study 

TABLE C5 

0 mg/m’ 0.25 mg/m’ 0.5 mg/m’ 1 mg/m’ 

Nose 

Respiratory System (continued) 

15-Month Interim Evaluation (continued) 

(5) (5) (5) (5) 

Vomeronasal organ, infiltration cellular, 

Respiratory epithelium, degeneration 

Olfactory epithelium, degeneration 

Olfactory epithelium, atrophy 

Glands, inflammation 

Inflammation, acute 

Developmental malformation 1 (20%) 

1 (20%) 

2 (40%) 

2 (40%) 

1 (20%) 

1 (20%) 

3 (60%) 

1 (20%) 

1 (20%) 

polymorphonuclear 1 (20%) 

Trachea (5) (5) (5) (5) 

Inflammation 1 (20%) 1 (20%) 

Urinary System 

Special Senses System 

Nervous System 

Musculoskeletal System 

General Body System 

Cardiovascular System 

Systems Examined With No Lesions Observed 

Esophagus 

Alimentary System 

2- Year Study 

Autolysis 

Gallbladder 

Hyperkeratosis 

Hemorrhage 

Autolysis 

Intestine large, colon 

Anus, inflammation 

Autolysis 

Intestine large, rectum 

Hyperplasia, lymphoid 

Autolysis 

Intestine large, cecum 

Autolysis 

Intestine small, duodenum 

Peyer’s patch, inflammation 

Peyer’s patch, hyperplasia 

Autolysis 

Intestine small, jejunum 

Autolysis 

(60) 

(56) 

(60) 

(61) 

(59) 

(61) 

(60) 

(56) 

(61) 

(59) 

(54) 

(61) 

2 (3%) 

1 (2%) 

1 (2%) 

1 (2%) 

1 (2%) 

1 (2%) 

3 (5%) 

1 (2%) 

(55) (57) (50) (50) 

1 (2%) 

1 (2%) 

1 (2%) 

4 (7%) 

1 (2%) 

1 (2%) 

(59) (60) (60) (58) 

2 (3%) 

1 (2%) 

(61) 

(61) 

(61) 

(60) 

(59) 

(59) 

(59) 

(56) 

1 (2%) 

1 (2%) 

1 (2%) 

1 (2%) 

3 (5%) 

2 (4%) 

I (2%) 1 (2%) 

Intestine small, ileum (59) (60) (57) (56) 

3 (5%) 
244 Nickel Sulfate Hexahydrate, NTP TR 454 

of Nickel Sulfate Hexahydrate (continued) 

Summary of the Incidence of Nonneoplastic Lesions in Male Mice in the 2-Year Inhalation Study 

TABLE C5 

0 mg/m3 0.25 mg/m3 0.5 mg/mJ 1 mg/m3 

Liver 

Alimentary System (continued) 

2-Year Study (continued) 

Centrilobular, degeneration 

Bile duct, cyst 

Pigmentation 

Necrosis, diffuse 

Necrosis 

Inflammation 

Infarct 

Hepatodiaphragmatic nodule 

Fatty change 

Eosinophilic focus 

cyst 

Congestion 

Clear cell focus 

Basophilic focus 

Autolysis 

Angiectasis, focal 

Inflammation 

Acinus, hyperplasia 

Inflammation 

cyst 

Autolysis 

Atrophy 

Autolysis 

Salivary glands 

Hyperplasia, squamous 

Hyperkeratosis 

Hyperplasia, squamous 

Autolysis 

Stomach, forestomach 

Peridontal tissue, inflammation 

Inflammation 

Autolysis 

Pancreas 

Mesentery 

Pharynx 

Stomach, glandular 

Tooth 

1 (2%) 

1 (2%) 

2 (3%) 4 (7%) 

1 (2%) 

1 (2%) 

1 (2%) 

1 (2%) 

1 (2%) 

6 (10%) 

2 (3%) 

1 (2%) 

3 (5%) 

1 (2%) 

5 (8%) 

5 (8%) 

1 (2%) 

1 (2%) 

1 (2%) 

1 (2%) 

7 (11%) 

1 (2%) 

1 (2%) 

1 (2%) 

7 (11%) 

1 (2%) 

(1) 

1 (2%) 

1 (2%) 

1 (2%) 

(1) 

1 (100%) 

(61) 

1 (2%) 

(60) 

1 (2%) 

(60) 

2 (3%) 

(2) 

2 (100%) 

Heart 

Cardiovascular System 

Atrium, thrombosis 

Thrombosis 

Inflammation 

Cardiomyopathy 

2 (3%) 
Lesions in Male Mice 245 

of Nickel Sulfate Hexahydrate (continued) 

Summary of the Incidence of Nonneoplastic Lesions in Male Mice in the 2-Year Inhalation Study 

TABLE C5 

0 mg/m3 0.25 mg/m3 0.5 mg/m3 1 mg/m3 

Adrenal cortex 

Endocrine System 

Capsule, hyperplasia 

Infarct 

Hypertrophy 

Hyperplasia 

Cyst multilocular 

Accessory adrenal cortical nodule 

Infarct 

Adrenal medulla 

Parathyroid gland 

Hyperplasia 

Islets, pancreatic 

Autolysis 

Pituitary gland 

Autolysis 

Pars distalis, hyperplasia 

Follicular cell, hyperplasia, cystic 

Follicular cell, hyperplasia 

Autolysis 

Thyroid gland 

cyst 

2 (3%) 1 (2%) 

1 (2%) 

1 (2%) 

3 (5%) 

1 (2%) 

1 (2%) 

(57) 

(54) 

1 (2%) 

(61) 

2 (4%) 

(61) (61) 

25 (41%) 

1 (2%) 

1 (2%) 

26 (43%) 26 (43%) 

Abdominal. abscess 

Tissue NOS 

General Body System 

Autolysis 

Epididymis 

Genital System 

Inflammation 

Hyperplasia, squamous 

Bacterium 

Penis 

Duct, hyperplasia 

Inflammation 

Ectasia 

cyst 

Autolysis 

Atrophy 

Preputial gland 

Inflammation 

Hyperplasia 

Congestion 

Autolysis 

Prostate 

4 (100%) 

2 (29%) 

2 (29%) 

(59) (59) 

1 (2%) 

35 (59%) 

31 (53%) 

1 (2%) 

1 (2%) 

1 (2%) 

1 (2%) 

(60) 

23 (39%) 

45 (76%) 

34 (57%) 

32 (53%) 

1 (2%) 

35 (58%) 

37 (62%) 

1 (2%) 

(61) 

3 (5%) 

1 (2%) 

3 (5%) 3 (5%) 2 (3%) 
246 Nickel Sulfate Hexahydrate, NTP TR 454 

of Nickel Sulfate Hexahydrate (continued) 

Summary of the Incidence of Nonneoplastic Lesions in Male Mice in the 2-Year Inhalation Study 

TABLE C5 

0 mg/m3 0.25 mg/m3 0.5 mg/m3 1 mg/m3 

Seminal vesicle 

Genital System (continued) 

2-Year Study (continued) 

Inflammation 

Hyperplasia 

Hemorrhage 

Ectasia 

Autolysis 

Tunic, inflammation 

Granuloma sperm 

Autolysis 

Atrophy 

Testes 

~~ 

~~~~ 

Hematopoietic System 

Myeloid cell, hyperplasia 

Erythroid cell, hyperplasia 

Autolysis 

Bone marrow 

Renal, inflammation 

Renal, hyperplasia, plasma cell 

Renal, hyperplasia, lymphoid 

Renal, hyperplasia, histiocytic 

Renal, congestion 

Popliteal, hyperplasia, plasma cell 

Pancreatic, thrombosis 

Pancreatic, hyperplasia, lymphoid 

Lumbar, hyperplasia, plasma cell 

Inguinal, pigmentation 

Inguinal, inflammation 

Inguinal, hyperplasia, plasma cell 

Inguinal, hyperplasia, lymphoid 

Inguinal, hyperplasia, histiocytic 

Iliac, pigmentation 

Iliac, inflammation 

Iliac, hyperplasia, plasma cell 

Iliac, hyperplasia, lymphoid 

Iliac, hyperplasia, histiocytic 

Inflammation 

Hyperplasia, plasma cell 

Hyperplasia, macrophage 

Hyperplasia, lymphoid 

Hyperplasia, histiocytic 

Hematopoietic cell proliferation 

Edema 

Congestion 

Lymph node, bronchial 

(61) (61 1 (61) (61) 

1 (4%) 

12 (20%) 

1 (2%) 

18 (30%) 

1 (2%) 

12 (50%) 

4 (17%) 

1 (4%) 

15 (25%) 12 (20%) 

Lymph node (24) (21) (20) (26) 

1 (5%) 

10 (48%) 

1 (5%) 

7 (35%) 

4 (20%) 

12 (46%) 

1 (4%) 

1 (5%) 

4 (20%) 

7 (35%) 

2 (10%) 

1 (5%) 

1 (5%) 

1 (5%) 

1 (2%) 

1 (5%) 

1 (5%) 

1 (5%) 

11 (42%) 

2 (8%) 

1 (4%) 

2 (8%) 

1 (4%) 

6 (25%) 

8 (33%) 

1 (5%) 

2 (10%) 

5 (24%) 

11 (52%) 

1 (4%) 

2 (8%) 

2 (8%) 

1 (4%) 

3 (12%) 

1 (4%) 

2 (8%) 

5 (21%) 

1 (4%) 2 (8%) 

1 (5%) 

(46) (49) (45) (54) 

1 (2%) 

4 (8%) 

2 (4%) 

1 (2%) 

2 (4%) 

1 (2%) 

1 (2%) 

1 (2%) 

2 (4%) 

8 (18%) 

2 (4%) 

39 (72%) 

17 (31%) 

1 (2%) 
Lesions in Male Mice 247 

of Nickel Sulfate Hexahydrate (continued) 

Summary of the Incidence of Nonneoplastic Lesions in Male Mice in the 2-Year Inhalation Study 

TABLE C5 

0 mg/m3 0.25 mg/m3 0.5 mg/m3 1 mg/m3 

Lymph node, mandibular 

Hematopoietic System (c'ontinued) 

2-YeUr study (continued) 

Inflammation 

Hyperplasia, plasma cell 

Hyperplasia, lymphoid 

Ectasia 

Inflammation 

Hyperplasia, lymphoid 

Hyperplasia, histiocytic 

Hematopoietic cell proliferation 

Edema 

Congestion 

Atrophy 

Angiectasis 

Pigmentation 

Hyperplasia, plasma cell 

Hyperplasia, lymphoid 

Hyperplasia, histiocytic 

Congestion 

Autolysis 

Lymph node, mediastinal 

Inflammation 

Hyperplasia, lymphoid 

Hyperplasia, histiocytic 

Hematopoietic cell proliferation 

Autolysis 

Angiectasis 

Atrophy 

Lymph node, mesenteric 

Spleen 

Thymus 

Skin 

Integumentary System 

Tail, necrosis 

Tail, inflammation 

Tail, hyperkeratosis 

Subcutaneous tissue, inflammation 

Subcutaneous tissue, edema 

Prepuce, inflammation 

Prepuce, hyperplasia, squamous 

Prepuce, edema 

Pinna, inflammation 

Foot, necrosis 

Foot, inflammation 

Necrosis 

Inflammation, chronic 

Inflammation 

Hyperplasia, squamous 

Hyperkeratosis 

(57) 

4 (7%) 

1 (2%) 

1 (2%) 

2 (4%) 

1 (2%) 

3 (6%) 

2 (4%) 

(53) 

1 (2%) 

1 (2%) 

1 (2%) 

(57) (54) 

2 (4%) 

1 (2%) 

1 (2%) 

4 (7%) 

1 (2%) 

2 (4%) 4 (8%) 1 (2%) 

5 (9%) 

4 (8%) 

2 (4%) 

2 (4%) 

(24) 

2 (4%) 

2 (4%) 

2 (4%) 

3 (6%) 

1 (4%) 

1 (4%) 

1 (4%) 

1 (4%) 

1 (4%) 

(23) 

5 (9%) 

(18) 

2 (8%) 

1 (6%) 

1 (6%) 

12 (20%) 

1 (2%) 

1 (4%) 

(61) 

1 (2%) 

1 (2%) 

9 (15%) 11 (18%) 

15 (31%) 

2 (3%) 

3 (5%) 

(49) 

1 (2%) 5 (8%) 

(55) 

28 (51%) 

(53) 

19 (36%) 

(45) 

13 (29%) 

(61) 

1 (2%) 

1 (2%) 

4 (6%) 

1 (2%) 

3 (5%) 

5 (8%) 1 (2%) 1 (2%) 

1 (2%) 

1 (2%) 

1 (2%) 

1 (2%) 

1 (2%) 

1 (2%) 

1 (2%) 

1 (2%) 

8 (13%) 

1 (2%) 

15 (25%) 19 (31%) 

1 (2%) 

13 (21%) 

11 (18%) 

5 (8%) 

1 (2%) 

1 (2%) 

6 (10%) 

2 (3%) 

1 (2%) 

4 (7%) 

2 (3%) 2 (3%) 

6 (10%) 
248 Nickel Sulfate Hexahydrate, NTP TR 454 

of Nickel Sulfate Hexahydrate (continued) 

Summary of the Incidence of Nonneoplastic Lesions in Male Mice in the 2-Year Inhalation Study 

TABLE C5 

0 mg/m3 0.25 mg/m3 0.5 mg/m3 1 mg/m3 

study (continued) 

Bone 

Musculoskeletal System 

Femur, osteoporosis 

Femur, hyperostosis 

Brain 

Nervous System 

Thalamus, degeneration 

Meninges, inflammation 

Hippocampus, degeneration 

Cerebrum, degeneration 

Congestion 

Autolysis 

Larynx 

Respiratory System 

(59) (59) (58) (62) 

Hyperplasia, squamous 

Autolysis 

Interstitium, infiltration cellular 

Bronchiole, hyperplasia 

Alveolus, proteinosis 

Bronchialization 

Thrombosis, multiple 

Inflammation, chronic active 

Inflammation 

Infarct 

Hyperplasia, macrophage 

Hemorrhage 

Fibrosis 

Congestion 

Autolysis 

Respiratory epithelium, metaplasia, squamous 1 (2%) 

Respiratory epithelium, inflammation 

Respiratory epithelium, degeneration 

Olfactory epithelium, inflammation 

Olfactory epithelium, degeneration 

Olfactory epithelium, atrophy 

Autolysis 

Epithelium, hyperplasia 

Autolysis 

1 (2%) 

1 (2%) 

1 (2%) 

1 (2%) 

35 (56%) 

1 (2%) 

1 (2%) 

1 (2%) 

Lung (61) (61) (62) (61) 

2 (3%) 

1 (2%) 

6 (10%) 

1 (2%) 

1 (2%) 

1 (2%) 

1 (2%) 

1 (2%) 

59 (97%) 

1 (2%) 

2 (3%) 

2 (3%) 

1 (2%) 

9 (15%) 

4 (7%) 19 (31%) 

8 (13%) 

42 (69%) 

39 (64%) 

1 (2%) 

29 (48%) 

37 (62%) 

1 (2%) 

17 (28%) 

5 (8%) 

2 (3%) 

1 (2%) 

3 (5%) 

Nose (61) (61) (61) (60) 

12 (20%) 

1 (2%) 

1 (2%) 

2 (3%) 

2 (3%) 

2 (3%) 

2 (3%) 

1 (2%) 

5 (8%) 

Trachea (61) (61) (61) (61) 

1 (2%) 

1 (2%) 1 (2%) 

EY e 

Special Senses System 

Phthisis bulbi 

(1) 

1 (100%) 
Lesions in Male Mice 249 

of Nickel Sulfate Hexahydrate (continued) 

Summary of the Incidence of Nonneoplastic Lesions in Male Mice in the 2-Year Inhalation Study 

TABLE C5 

0 mg/m3 0.25 mg/m3 0.5 mg/m3 1 mg/m3 

&"y (continued) 

Kidney 

Urinary System - 

Renal tubule, pigmentation 

Pelvis, dilatation 

Cortex, cyst 

Nephropathy 

Mineralization 

Metaplasia, osseous 

Inflammation 

Hydronephrosis 

Fibrosis 

Dilatation 

Congestion 

Autolysis 

Inflammation 

Dilatation 

Transitional epithelium, hyperplasia 

Inflammation 

Calculus, microscopic observation only 

Transitional epithelium, metaplasia, squamous 

Transitional epithelium, hyperplasia 

Inflammation 

Hemorrhage 

Dilatation 

Congestion 

Calculus, microscopic observation only 

Autolysis 

Urinary bladder 

Ureter 

Urethra 

(61) 

8 (13%) 

16 (26%) 

9 (15%) 

1 (2%) 

(2) 

1 (10%) 

10 (100%) 

1 (50%) 

1 (50%) 

( 10) 

(60) 

I (12%) 

1 (2%) 

1 (2%) 

1 (2%) 

(61) 

1 (2%) 

1 (2%) 

1 (2%) 

7 (11%) 

19 (31%) 

2 (3%) 

8 (13%) 

1 (2%) 

(13) 

2 (15%) 

4 (31%) 

8 (62%) 

2 (3%) 

1 (2%) 

(60) 

1 (2%) 

1 (2%) 

6 (10%) 

(61) 

8 (13%) 

2 (3%) 

10 (16%) 

1 (2%) 

9 (15%) 

(1) 

1 (100%) 

(15) 

15 (100%) 

3 (20%) 

(60) 

1 (2%) 

9 (15%) 

1 (2%) 

1 (2%) 

1 (2%) 

1 (2%) 

(61) 

1 (2%) 

8 (13%) 

2 (3%) 

1 (2%) 

7 (11%) 

(2) 

10 (16%) 

5 (31%) 

14 (88%) 

2 (100%) 

(16) 

(59) 

2 (3%) 

3 (5%) 

6 (10%) 

1 (2%) 

2 (3%) 
250 Nickel Sulfate Hexahydrate, NTP TR 454 
251 

OF NICKEL SULFATE HEXAHYDRATE 

SUMMARY OF LESIONS IN FEMALE MICE 

APPENDIX D 

IN THE 2-YEAR INHALATION STUDY 

TABLE D5 Summary of the Incidence of Nonneoplastic Lesions in Female Mice 

TABLE D4 Historical Incidence of Alveolar/bronchiolar Neoplasms 

TABLE D3 Statistical Analysis of Primary Neoplasms in Female Mice 

TABLE D2 Individual Animal Tumor Pathology of Female Mice 

TABLE Dl Summary of the Incidence of Neoplasms in Female Mice 

in the 2-Year Inhalation Study of Nickel Sulfate Hexahydrate 

in Untreated Female B6C3Fl Mice 

in the 2-Year Inhalation Study of Nickel Sulfate Hexahydrate 

in the 2-Year Inhalation Study of Nickel Sulfate Hexahydrate 

in the 2-Year Inhalation Study of Nickel Sulfate Hexahydrate ................ 

303 

302 

298 

259 

252 

................ 

................ 

.................................. 

................ 
252 Nickel Sulfate Hexahydrate, NTP TR 454 

Summary of the Incidence of Neoplasms in Female Mice in the 2-Year Inhalation Study of Nickel Sulfate Hexahydratea 

TABLE Dl 

0 mg/m3 0.25 mg/m3 0.5 mg/m3 1 mg/m3 

Early deaths 

15-Month interim evaluation 

%Month interim evaluation 

Animals initially in study 

Disposition Summary 

Terminal sacrifice 

Died last week of study 

Natural deaths 

Moribund 

Survivors 

5 

5 

71 

7 

20 

33 

1 

5 

5 

70 

10 

11 

38 

1 

5 

5 

70 

4 

11 

45 

5 

5 

70 

6 

17 

31 

Animals examined microscopically 71 70 70 70 

Urinary System 

Special Senses System 

Respiratory System 

Nervous System 

Musculoskeletal System 

integumentary System 

Hematopoietic System 

Genital System 

General Body System 

Endocrine System 

Cardiovascular System 

Alimentary System 

Systems Examined At 7 Months With No Neoplasms Observed 

15-Month Interim Evaluation 

Liver 

Alimentary System 

Hepatocellular adenoma 

(5) (5) 

2 (40%) 1 (20%) 

Ovary 

Genital System 

Luteoma 

(5) 

1 (20%) 

Harderian gland 

Special Senses System 

Adenoma 
Lesions in Female Mice 253 

(continued) 

Summary of the Incidence of Neoplasms in Female Mice in the 2-Year Inhalation Study of Nickel Sulfate Hexahydrate 

TABLE Dl 

O mg/m3 0.25 mg/m3 0.5 mg/m3 1 mg/m3 

Urinary System 

Respiratory System 

Nervous System 

Musculoskeletal System 

Integumentary System 

Hematopoietic System 

General Body System 

Endocrine System 

Cardiovascular System 

Systems Examined With No Neoplasms Observed 

15-Month Interim Evaluation (continued) 

2-Year Study 

Intestine large, cecum 

Intestine large, rectum 

Intestine large, colon 

Gallbladder 

Alimentary System 

Wall, cholangiocarcinoma, metastatic, liver 

Lymphatic, cholangiocarcinoma, metastatic, 

Anus, squamous cell papilloma 

liver 

Intestine small, duodenum 

Serosa, cholangiocarcinoma, metastatic, liver 

Histiocytic sarcoma 

Adenocalcinoma 

Intestine small, jejunum 

Liver 

Intestine small, ileum 

Histiocytic sarcoma 

Pheochromocytoma malignant, metastatic, 

Osteosarcoma, metastatic, bone 

Histiocytic sarcoma 

Hepatocellular adenoma, multiple 

Hepatocellular adenoma 

Hepatocellular carcinoma, multiple 

Hepatocellular carcinoma 

Hemangiosarcoma 

Cholangiocarcinoma 

Carcinoma, metastatic, lung 

adrenal medulla 

Mesentery 

Histiocytic sarcoma 

Fibrosarcoma, metastatic, skeletal muscle 

Fibrosarcoma, metastatic, skin 

Cholangiocarcinoma, metastatic, liver 

Carcinoma, metastatic, lung 

1 (2%) 

(57) (59) 

1 (2%) 

1 (2%) 

1 (2%) 

3 (5%) 

1 (2%) 

8 (13%) 

1 (2%) 

10 (17%) 

1 (2%) 

7 (11%) 

2 (3%) 

1 (2%) 

13 (22%) 

5 (8%) 

9 (15%) 5 (8%) 

2 (3%) 

1 (2%) 

10 (17%) 

1 (2%) 

2 (3%) 

11 (18%) 

1 (2%) 

(4) (4) 

1 (25%) 

1 (25%) 

1 (14%) 

1 (14%) 

1 (20%) 

1 (20%) 

1 (25%) 
254 Nickel Sulfate Hexahydrate, NTP TR 454 

O mg/m3 0.25 mg/m3 0.5 mg/m3 1 mg/m’ 

Pancreas 

Alimentary System (continued) 

%Year Study (continued) 

(60) 

Histiocytic sarcoma 

Fibrosarcoma, metastatic, skin 

Cholangiocarcinoma, metastatic, liver 

Salivary glands 

Serosa, cholangiocarcinoma, metastatic, liver 

Squamous cell papilloma 

Histiocytic sarcoma 

Stomach, forestomach 

Carcinoma, metastatic, lung 

1 (2%) 

1 (2%) 

(61) 

(61) 

Stomach, glandular (60) 

Heart 

Cardiovascular System 

(61) (59) (60) (60) 

Neoplasm NOS, metastatic, uncertain primary 

Fibrosarcoma, metastatic, skin 

Carcinoma, metastatic, lung 

Epicardium, cholangiocarcinoma. metastatic, 

1 (2%) 

1 (2%) 

liver 

site 

1 (2%) 

1 (2%) 

Endocrine System 

Extra adrenal tissue, carcinoma, metastatic, 

Capsule, adenoma 

Adrenal cortex 

Pheochromocytoma malignant 

Extra adrenal tissue, histiocytic sarcoma 

Extra adrenal tissue, cholangiocarcinoma, 

Cholangiocarcinoma, metastatic, liver 

Adenoma 

Pheochromocytoma benign 

metastatic, liver 

lung 

Adrenal medulla 

Islets, pancreatic 

Pituitary gland 

Parathyroid gland 

Pars intermedia, adenoma 

Pars distalis, adenoma 

Follicular cell, adenoma, multiple 

Follicular cell, adenoma 

Carcinoma, metastatic, lung 

Thyroid gland 

(60) 

1 (2%) 

1 (2%) 

1 (2%) 

1 (2%) 

1 (2%) 

1 (2%) 

(60) 

(59) 

1 (2%) 

2 (3%) 

(60) 

1 (2%) 
Lesions in Female Mice 255 

(continued) 

Summary of the Incidence of Neoplasms in Female Mice in the 2-Year Inhalation Study of Nickel Sulfate Hexahydrate 

TABLE Dl 

0 mg/m3 0.25 mg/m3 0.5 mg/m3 1 mg/m3 

SfZ" (continued) 

Tissue NOS 

General Body System 

(5) (8) (4) (3) 

Mediastinum, cholangiocarcinoma, metastatic, 

Mediastinum, carcinoma, metastatic, lung 

Fibrosarcoma, metastatic, skin 

Thoracic, neoplasm NOS, metastatic, 

Thoracic, carcinoma, metastatic, lung 

Mediastinum, fibrosarcoma, metastatic, skin 1 (20%) 

1 (25%) 

1 (25%) 

liver 1 (13%) 

1 (25%) 

uncertain primary site 1 (13%) 

Genital System 

Bilateral, cholangiocarcinoma, metastatic, 

Tubulostromal adenoma 

Histiocytic sarcoma 

Granulosa cell tumor benign 

Granulosa cell tumor malignant 

Cystadenoma 

Ovary 

Periovarian tissue, histiocytic sarcoma 

Polyp stromal, multiple 

Polyp stromal 

Leiomyosarcoma 

Leiomyoma 

Histiocytic sarcoma 

Hemangioma 

Fibroma 

Cholangiocarcinoma, metastatic, liver 

Fibroma 

liver 

Uterus 

Vagina 

(59) 

2 (3%) 

1 (2%) 

1 (2%) 

1 (2%) 

1 (2%) 

1 (2%) 

1 (2%) 

1 (2%) 

1 (2%) 

1 (2%) 

1 (2%) 1 (2%) 2 (3%) 

1 (2%) 

2 (3%) 1 (2%) 

1 (2%) 

2 (3%) 

Lymph node 

Bone marrow 

Hematopoietic System 

(11) 

(61) 

Histiocytic sarcoma 

Inguinal, histiocytic sarcoma 1 (9%) 

Inguinal, carcinoma, metastatic, lung 

Iliac, histiocytic sarcoma 1 (9%) 

Iliac, fibrosarcoma, metastatic, skin 1 (9%) 

Axillary, histiocytic sarcoma 

Axillary, fibrosarcoma, metastatic, skin 1 (9%) 

Axillary, carcinoma, metastatic, lung 

1 (8%) 

1 (9%) 

1 (9%) 

1 (8%) 

1 (8%) 1 (8%) 

Renal, histiocytic sarcoma 

Pancreatic, neoplasm NOS 

Pancreatic, histiocytic sarcoma 

Pancreatic, carcinoma, metastatic, lung 

1 (9%) 

1 (9%) 

1 (9%) 2 (15%) 

1 (8%) 

1 (8%) 

1 (8%) 

1 (8%) 

3 (23%) 
256 Nickel Sulfate Hexahydrate, NTP TR 454 

(continued) 

Summary of the Incidence of Neoplasms in Female Mice in the 2-Year Inhalation Study of Nickel Sulfate Hexahydrate 

TABLE Dl 

O mg/m’ 0.25 mg/m3 0.5 mg/m3 1 mg/m3 

Lymph node, bronchial 

Hematopoietic System (continued) 

study (continued) 

Neoplasm NOS, metastatic, uncertain primary 

Neoplasm NOS, metastatic, lung 

Histiocytic sarcoma 

Fibrosarcoma, metastatic, skin 

Cholangiocarcinoma, metastatic, liver 

Carcinoma, metastatic, lung 

site 

Mast cell tumor benign 

Histiocytic sarcoma 

Carcinoma, metastatic 

Lymph node, mandibular 

Histiocytic sarcoma 

Cholangiocarcinoma, metastatic, liver 

Carcinoma, metastatic, lung 

Lymph node, mesenteric 

Neoplasm NOS, metastatic, uncertain primary 

Histiocytic sarcoma 

Fibrosarcoma, metastatic, skin 

Cholangiocarcinoma, metastatic, liver 

Carcinoma, metastatic, lung 

Lymph node, mediastinal 

site 

Spleen 

Capsule, cholangiocarcinoma, metastatic, 

Histiocytic sarcoma 

Hemangiosarcoma 

liver 

Thymus 

Neoplasm NOS, metastatic, uncertain primary 

Histiocytic sarcoma 

Fibrosarcoma, metastatic, skin 

Cholangiocarcinoma, metastatic, liver 

Carcinoma, metastatic, lung 

site 

(58) 

1 (2%) 

(56) 

1 (2%) 

1 (2%) 

1 (2%) 

1 (2%) 

1 (2%) 

1 (2%) 1 (2%) 2 (4%) 

1 f2%) 

(56) 

1 (2%) 2 (3%) 

(56) 

1 (2%) 

1 (3%) 

2 (4%) 

(33) 

1 (2%) 

(30) 

1 (4%) 

1 (3%) 

1 (4%) 1 (3%) 1 (5%) 

1 (4%) 

(58) (60) 

1 (2%) 

(60) 

2 (3%) 1 (2%) 

1 (2%) 

(54) (56) 

1 (2%) 

1 (2%) 

1 (2%) 

1 (2%) 

2 (4%) 

1 (2%) 

Integumentary System 

Fibroadenoma 

Carcinoma 

Mammary gland 

Subcutaneous tissue, carcinoma, metastatic, 

Squamous cell papilloma 

Basosquamous tumor malignant 

(61) 

2 (3%) 

Skin (61) 

1 (2%) 

(60) 

1 (2%) 

lung 

Subcutaneous tissue, fibrosarcoma 5 (8%) 1 (2%) 

2 (3%) 

Subcutaneous tissue, hemangioma 1 (2%) 
Lesions in Female Mice 257 

(continued) 

Summary of the Incidence of Neoplasms in Female Mice in the 2-Year Inhalation Study of Nickel Sulfate Hexahydrate 

TABLE Dl 

O mg/m3 0.25 mg/m3 0.5 mg/m3 1 mg/m3 

Bone 

Musculoskeletal System 

2-YelZr study (continued) 

(61) 

Vertebra, osteosarcoma 

Maxilla, histiocytic sarcoma 

Maxilla, fibrosarcoma, metastatic, skin 1 (2%) 

Diaphragm, cholangiocarcinoma, metastatic, 

Abdominal, cholangiocarcinoma, metastatic, 

Abdominal, carcinoma, metastatic, lung 

Neoplasm NOS, metastatic, uncehin primary 

Fibrosarcoma, metastatic, skin 

Skeletal muscle (4) 

1 (25%) 

site 

liver 

liver 

1 (2%) 

(3) 

1 (33%) 

1 (33%) 

1 (33%) 

1 (33%) 

1 (2%) 

Brain 

Nervous System 

Lung 

Larynx 

Respiratory System 

(61) 

(58) 

(60) 

(56) 

(60) 

(58) 

(60) 

(56) 

Alveolar/bronchiolar carcinoma 

Alveolarlbronchiolar adenoma 

Carcinoma, metastatic, lung 1 (2%) 

4 (7%) 

3 (5%) 

3 (5%) 

3 (5%) 2 (3%) 

8 (13%) 1 (2%) 

Neoplasm NOS 

Histiocytic sarcoma 

Hepatocellular carcinoma, metastatic, liver 

Hepatocellular carcinoma, metastatic 

Fibrosarcoma, metastatic, skin 

Cholangiocarcinoma, metastatic, liver 

Carcinoma 

Alveolar/bronchiolar carcinoma, multiple 

1 (2%) 

1 (2%) 

2 (3%) 

1 (2%) 

1 (2%) 

1 (2%) 

1 (2%) 

1 (2%) 

1 (2%) 

1 (2%) 

1 (2%) 

1 (2%) 

Neoplasm NOS, metastatic, uncertain primary 

Trachea 

site 

(61) 

Special Senses System 

Carcinoma 

Zymbal’s gland 

Adenoma 

Harderian gland 
258 Nickel Sulfate Hexahydrate, NTP TR 454 

(continued) 

Summary of the Incidence of Neoplasms in Female Mice in the 2-Year Inhalation Study of Nickel Sulfate Hexahydrate 

TABLE Dl 

O mg/m3 0.25 mg/m3 0.5 mg/m3 1 mg/m3 

Kidney 

Urinary System 

2-Yew Study (continued) 

(61) (60) (60) (60) 

Perirenal tissue, cholangiocarcinoma, 

Histiocytic sarcoma 

Fibrosarcoma, metastatic, skin 

Carcinoma, metastatic, lung 

metastatic, liver 

1 (2%) 

1 (2%) 

1 (2%) 

1 (2%) 

1 (2%) 

1 (2%) 2 (3%) 

Urinary bladder (59) (60) (58) (58) 

Serosa, cholangiocarcinoma, metastatic, liver 

Multiple organsb 

Systemic Lesions 

Lymphoma malignant 

Histiocytic sarcoma 

(61) (60) (60) (60) 

7 (11%) 

1 (2%) 

12 (20%) 

4 (7%) 

9 (15%) 

2 (3%) 4 (7%) 

6 (10%) 

Total animals with primary neoplasms' 

Neoplasm Summary 

15-Month interim evaluation 

2-Year study 

15-Month interim evaluation 

2-Year study 

15-Month interim evaluation 

2-Year study 

15-Month interim evaluation 

uncertain primary site 

2-Year study 

2-Year study 

2-Year study 

2-Year study 

2-Year study 

2-Year study 

Total uncertain neoplasms 

2-Year study 

benign or malignant 

2-Year study 

41 

Total primaIy neoplasms 

63 

Total animals with benign neoplasms 

27 

Total benign neoplasms 

3 

28 

26 

35 

Total animals with malignant neoplasms 

Total metastatic neoplasms 

Total animals with metastatic neoplasms 

Total malignant neoplasms 

Total animals with malignant neoplasms 

14 

Total animals with uncertain neoplasms - 

45 

1 

78 

1 

34 

1 

41 

1 

27 

37 

33 

5 

1 

40 

2 

58 

2 

22 

2 

28 

2 

26 

29 

2 

15 

36 

2 

49 

2 

16 

2 

20 

2 

25 

28 

6 

13 

a Number of animals examined microscopically at the site and the number of animals with neoplasm 

Primary neoplasms: all neoplasms except metastatic neoplasms 

Number of animals with any tissue examined microscopically 
Lesions in Female Mice 259 

0 mg/m3 

Individual Animal Tumor Pathology of Female Mice in the 2-Year Inhalation Study of Nickel Sulfate Hexahydrate: 

TABLE D2 

Number of Days on Study 

~~~ ~ ~~ ~ ~ 

5854800755867794506057443 

3538943489922225579000112 

0233345555566666666777777 

7840804963912508261338473 

1102832255801243511949991 

1111011111011111111010001 

Carqass ID Number 

Liver 

Intestine small, ileum 

Intestine small, jejunum 

Intestine small, duodenum 

Intestine large, cecum 

Intestine large, rectum 

Intestine large, colon 

Gallbladder 

Esophagus 

Alimentary System 

Histiocytic sarcoma 

Hepatocellular adenoma, multiple 

Hepatocellular adenoma 

Hepatocellular carcinoma 

Fibrosarcoma, metastatic, skin 

Histiocytic sarcoma 

Fibrosarcoma, metastatic, skin 

Stomach, glandular 

Stomach, forestomach 

Salivaly glands 

Histiocytic sarcoma 

MesenteIy 

Pancreas 

......................... 

......................... 

......................... 

+++++M+M+++++++++++++++++ 

......................... 

++++++++++++++++I +++++I +M 

......................... 

......................... 

......................... 

X 

X 

X X 

X 

+ 

X 

+ + 

X 

++ 

X 

++++++++++++++++++++++++M 

X .I A 

......................... 

......................... 

......................... 

Heart 

Cardiovascular System 

Fibrosarcoma, metastatic, skin 

......................... X 

Pheochromocytoma benign 

Adrenal medulla 

Capsule, adenoma 

Adrenal cortex 

Endocrine System 

Parathyroid gland 

Adenoma 

Islets, pancreatic 

Thyroid gland 

Pituitary gland 

+++++++++++++++++M+++++++ 

+++++++++++++++++M+++++++ 

X 

MMM+++++MMMIM++++M+++++MM 

......................... X 

++++++++++++++++++++++++M 

xx xx 

++++++++++++++M++++++++++ 

Follicular cell, adenoma 

Pars distalis, adenoma 

Tissue NOS 

General Body System 

+ ++ + 

Mediastinum, fibrosarcoma, 

metastatic, skin X 

A: Autolysis precludes examination 

+ : Tissue examined microscopically 

I: Insufficient tissue 

M: Missing tissue 

Blank: Not examined 

X: Lesion present 
260 Nickel Sulfate Hexahydrate, NTF' TR 454 

TABLE D2 

0 mg/m3 (continued) 

Individual Animal Tumor Pathology of Female Mice in the 2-Year Inhalation Study of Nickel Sulfate Hexahydrate: 

2233333333333333333333333 

7777777777777777777717717 

Number of Days on Study 

lOOOllllllOOOlltlllllllOl 

58000000001111~~1~2222233 

Carcass ID Number 

8155235349202172150681072 

0889001333899223440223684 

Intestine small, duodenum 

Intestine large, cecum 

Intestine large, rectum 

Intestine large, colon 

Gallbladder 

Esophagus 

Alimentary System 

+++++++++++++++++M+++++++ 

......................... 

++++++++I++++++++++++++++ 

......................... 

+++++++++++++++++++I+++++ 

......................... 

Liver 

Intestine small, ileum 

Intestine small, jejunum 

......................... 

......................... 

......................... 

Hepatocellular adenoma, multiple 

Hepatocellular adenoma 

Hepatocellular carcinoma X 

X 

X X 

X X 

X X 

Fibrosarcoma, metastatic, skin 

Histiocytic sarcoma 

Fibrosarcoma, metastatic, skin 

Histiocytic sarcoma 

Stomach, glandular 

Stomach, forestomach 

Salivary glands 

Histiocytic sarcoma 

Mesentery 

Pancreas 

+ + 

......................... 

......................... 

.......................... 

+++M+++++++++++++++++++++ 

Heart 

Cardiovascular System ......................... Fibrosarcoma, metastatic, skin 

Pheochromocytoma benign 

Adrenal medulla 

Capsule, adenoma 

Adrenal cortex 

Endocrine System 

Parathyroid gland 

Adenoma 

Islets, pancreatic 

Thyroid gland 

Pituitary gland 

Follicular cell, adenoma 

Pars distalis, adenoma 

......................... 

......................... 'x 

+++++++++++++I+++++++++++ 

++++M++++++++++++-++++++++ 

M+++++++++++MMM++M+MM+II + 

X X X 

......................... 

Tissue NOS 

General Body System 

Mediastinum, fibrosarcoma, 

metastatic, skin 

+ 
Lesions in Female Mice 261 

0 mg/m3 (continued) 

Individual Animal Tumor Pathology of Female Mice in the 2-Year Inhalation Study of Nickel Sulfate Hexahydrate: 

TABLE D2 

Number of Days on Study 

33346666666 

33333333333 

77777777777 

Carcass ID Number 

61436165707 

45528990355 

11110001111 

Tumors 

Tissues/ 

Total 

Gallbladder 

Esophagus 

Alimentary System 

+++++++++++ 

+++++++++++ 

60 

61 

Liver 

Intestine small, ileum 

Intestine small, jejunum 

Intestine small, duodenum 

Intestine large, cecum 

Intestine large, rectum 

Intestine large, colon 

Histiocytic sarcoma 

Hepatocellular adenoma, multiple 

Hepatocellular adenoma 

Hepatocellular carcinoma 

Fibrosarcoma, metastatic, skin 

Histiocytic sarcoma 

Fibrosarcoma, metastatic, skin 

Stomach, glandular 

Stomach, forestomach 

Salivary glands 

Histiocytic sarcoma 

Mesentery 

Pancreas 

+++++++++++ 

+++++++++++ 

+++++++++++ 

+++++++++++ 

+++++++++++ 

+++++++++++ 

+++++++++++ 

xx xx x X 

X 

+++++++++++ 

+++++++++++ 

+++++++++++ 

+++++++++++ 

1 

1 

7 

1 

2 

11 

7 

61 

61 

61 

58 

61 

57 

61 

60 

61 

61 

1 

1 

60 

Heart 

Cardiovascular System 

Fibrosarcoma, metastatic, skin 

+++++++++++ 

1 

61 

Adrenal cortex 

Endocrine System 

+++++++++++ 60 

Pheochromocytoma benign 

Adrenal medulla 

Capsule, adenoma 

Parathyroid gland 

Adenoma 

Islets, pancreatic 

Thyroid gland 

Pituitary gland 

Follicular cell, adenoma 

Pars distalis, adenoma 

+++++++++++ 

+++++++++++ 

X 

+++++++++++ 

X 

+++++++++++ 

+++I +++++++ 

X 1 

60 

8 

59 

40 

2 

60 

1 

60 

1 

Tissue NOS 

General Body System 

1 

5 

Mediastinum, fibrosarcoma, 

metastatic, skin 

Lesions in Female Mice 263 

0 mg/m3 (continued) 

Individual Animal Tumor Pathology of Female Mice in the 2-Year Inhalation Study of Nickel Sulfate Hexahydrate: 

TABLE D2 

5800000000111111112222233 

2233333333333333333333333 

I177771777777777777717777 

8155235349202172150681072 

0889001333899223440223684 

1000111111000111111111101 

Number of Days on Study 

Carcass ID Number 

Ovary 

Clitoral gland 

Genital System 

Histiocytic sarcoma 

Granulosa cell tumor benign 

Cystadenoma 

Polyp stromal 

Leiomyoma 

Histiocytic sarcoma 

Uterus 

X 

......................... 

......................... 

X 

......................... 

X X 

Lymph node 

Bone marrow 

Hematopoietic System 

Renal, histiocytic sarcoma 

Pancreatic, histiocytic sarcoma 

Inguinal, histiocytic sarcoma 

Iliac, histiocytic sarcoma 

Iliac, fibrosarcoma, metastatic, skin 

Axillary, fibrosarcoma, metastatic, skin 

Histiocytic sarcoma 

Fibrosarcoma, metastatic, skin 

Lymph node, bronchial 

Lymph node, mediastinal 

Histiocytic sarcoma 

Lymph node, mesenteric 

Lymph node, mandibular 

Fibrosarcoma, metastatic, skin 

Histiocytic sarcoma 

Hemangiosarcoma 

Spleen 

Histiocytic sarcoma 

Fibrosarcoma, metastatic, skin 

Thymus 

+ 

......................... + + 

++++++++++++++++++++I++++ 

++++++M++++++MI++++++++++ 

t++++++++++++M++I++++++++ 

+MMM+I ++++++++M+I ""+I MI 

......................... 

......................... 

Skin 

Carcinoma 

Mammary gland 

Integumentary System 

Subcutaneous tissue, fibrosarcoma 

Basosquamous tumor malignant 

......................... X 

......................... X 

Bone 

Musculoskeletal System 

......................... 

Fibrosarcoma, metastatic, skin 

Maxilla, fibrosarcoma, metastatic, skin 

Skeletal muscle + 

Brain 

Nervous System 

......................... 
264 Nickel Sulfate Hexahydrate, NTP TR 454 

TABLE D2 

0 mg/m3 (continued) 

Individual Animal Tumor Pathology of Female Mice in the 2-Year Inhalation Study of Nickel Sulfate Hexahydrate: 

33346666666 

33333333333 

77777777777 

61436165707 

45528990355 

11110001111 

Number of Days on Study 

Tumors 

Tissues/ 

Total 

Carcass ID Number 

Ovary 

Clitoral gland 

Genital System 

+++++++++++ 

+++++++++++ 

2 

1 

1 

61 

1 

1 

2 

59 

58 

Histiocytic sarcoma 

Granulosa ceil tumor benign 

Cystadenoma 

Polyp stromal 

Leiomyoma 

Histiocytic sarcoma 

X 

uterus +++++++++++ 

Lymph node 

Bone marrow 

Hematopoietic System 

+++++++++++ 

+ 

Renal, histiocytic sarcoma 

Pancreatic, histiocytic sarcoma 

Inguinal, histiocytic sarcoma 

Iliac, histiocytic sarcoma 

Iliac, fibrosarcoma, metastatic, skin 

Axillary, fibrosarcoma, metastatic, skin 

Histiocytic sarcoma 

Fibrosarcoma, metastatic, skin 

Lymph node, bronchial 

Lymph node, mediastinal 

Histiocytic sarcoma 

Lymph node, mesenteric 

Lymph node, mandibular 

Fibrosarcoma, metastatic, skin 

Histiocytic sarcoma 

Hemangiosarcoma 

Spleen 

Histiocytic sarcoma 

Fibrosarcoma, metastatic, skin 

Thymus 

++I +I ++++++ 

+++++++++++ 

++++++M++++ 

+“++I M++++ 

+++++++++++ 

X 

M+++M++++++ 

1 

1 

1 

11 

61 

1 

1 

1 

1 

1 

50 

1 

1 

58 

1 

1 

61 

1 

30 

1 

57 

56 

Skin 

Carcinoma 

Mammary gland 

Integumentary System 

+++++++++++ 

61 

2 

61 

X 

+++++++++++ 

Subcutaneous tissue, fibrosarcoma 

Basosquamous tumor malignant 

5 

1 

Skeletal muscle 

Bone 

Musculoskeletal System 

+++++++++++ 

Fibrosarcoma, metastatic, skin 

Maxilla, fibrosarcoma, metastatic, skin 

+ 

1 

4 

1 

61 

Brain 

Nervous System 

+++++++++++ 61 
Lesions in Female Mice 265 

0 mgh3 (continued) 

Individual Animal Tumor Pathology of Female Mice in the 2-Year Inhalation Study of Nickel Sulfate Hexahydrate: 

TABLE D2 

5854800155867194506057443 

3538943489922225579000112 

0233345555566666666111117 

I840804963912508261338413 

1102832255801243511949991 

1111011111011111111010001 

Number of Days on Study 

Carcass ID Number 

Lung 

Larynx 

Respiratory System 

......................... 

M++++I++++++++++++++++++M 

Hepatocellular carcinoma, metastatic, liver 

Fibrosarcoma, metastatic, skin 

Alveolar/bronchiolar carcinoma 

Alveolarlbronchiolar adenoma 

X 

X 

X 

Trachea 

Nose 

......................... 

......................... 

None 

Special Senses System 

Urinary bladder 

Kidney 

Urinary System 

Fibrosarcoma, metastatic, skin 

......................... X ........................ 

Multiple organs 

Systemic Lesions 

Lymphoma malignant 

Histiocytic sarcoma 

xx 

......................... X 

X 
266 Nickel Sulfate Hexahydrate, NTP TR 454 

O mg/m3 (continued) 

Individual Animal Tumor Pathology of Female Mice in the 2-Year Inhalation Study of Nickel Sulfate Hexahydrate: 

TABLE D2 

5800000000111111112222233 

2233333333333333333333333 

7777777777777777777777777 

Number of Days on Study 

Carcass ID Number 

lOOOllflllOOOllllllllllOl 

8155235349202172150681072 

0889001333899223440223684 

Lung 

Larynx 

Respiratory System 

Alveolarhronchiolar carcinoma 

Alveolarhronchiolar adenoma 

......................... 

.......................... X 

xx X 

Hepatocellular carcinoma, metastatic, liver 

Fibrosarcoma, metastatic, skin 

Trachea 

Nose 

......................... 

......................... 

None 

Special Senses System 

Urinary bladder 

Kidney 

Urinary System 

Fibrosarcoma, metastatic, skin 

++++++++++I++++++++++++++ 

......................... 

Multiple organs 

Systemic Lesions 

X 

......................... 

Lymphoma malignant 

Histiocytic sarcoma 

X X X 
Lesions in Female Mice 267 

O mg/m3 (continued) 

Individual Animal Tumor Pathology of Female Mice in the 2-Year Inhalation Study of Nickel Sulfate Hexahydrate: 

TABLE D2 

33346666666 

33333333333 

77777777777 

61436165707 

45528990355 

11110001111 

Number of Days on Study 

Tumors 

Tissues/ 

Total 

Carcass ID Number 

Lung 

Larynx 

Respiratory System 

+++++++++++ 

+++++++++++ 

61 

61 

1 

1 

4 

3 

61 

58 

Hepatocellular carcinoma, metastatic, liver 

Fibrosarcoma, metastatic, skin 

Alveolar/bronchiolar carcinoma 

Alveolar/bronchiolar adenoma xx 

Trachea 

Nose 

+++++++++++ 

+++++++++++ 

None 

Special Senses System 

Urinary System 

Systemic Lesions 

Urinary bladder 

Kidney 

Multiple organs 

+++++++++++ 

59 

1 

61 

Fibrosarcoma, metastatic, skin 

+++++++++++ 

+++++++++++ 

7 

1 

61 

Lymphoma malignant 

Histiocytic sarcoma 
268 Nickel Sulfate Hexahydrate, NTP TR 454 

0.25 mglm’ 

Individual Animal Tumor Pathology of Female Mice in the 2-Year Inhalation Study of Nickel Sulfate Hexahydrate: 

TABLE D2 

Number of Days on Study 

4158319884459629731580000 

1679815781234677801223333 

0333455556666666677777777 

~ ~~~~~~~~~~~~~~~~ 

Carcass ID Number 

2795778166337600326187030 

6500078805976626481444568 

2233322232222232223222222 

Gallbladder 

Esophagus 

Alimentary System 

+++M++++M++++AM+++++A++++ 

++++M++++++++++++++++++++ 

Wall, cholangiocarcinoma, metastatic, liver X 

Intestine large, cecum 

Intestine large, rectum 

Intestine large, colon 

++++++++A++++AA++++++++++ 

++++++++A++++A+++++++++++ 

++++++++A++++AA++++++++++ 

Lymphatic, cholangiocarcinoma, 

Anus, squamous cell papilloma X 

Histiocytic sarcoma 

Intestine small, duodenum 

metastatic, liver 

Serosa, cholangiocarcinoma, 

X 

++++++++A++++A+++++++++++ 

Intestine small, jejunum 

metastatic, liver 

Liver 

Intestine small, ileum 

Histiocytic sarcoma 

X 

++++++++A++++A+++++++++++ 

++++++++A++++A+++++++++++ 

+++++++++++++A+++++++++++ 

Pheochromocytoma malignant, metastatic, 

Histiocytic sarcoma 

Hepatocellular adenoma, multiple 

Hepatocellular adenoma 

Hepatocellular carcinoma, multiple 

Hepatocellular carcinoma 

Cholangiocarcinoma 

adrenal medulla 

xx x x X X 

X 

X xx X 

X 

SalivaIy glands 

Pancreas 

Mesentery 

Squamous cell papilloma 

Histiocytic sarcoma 

Stomach, forestomach 

Cholangiocarcinoma, metastatic, liver 

Cholangiocarcinoma, metastatic, liver 

X 

X 

X 

X 

X 

+ ++ + 

++++++++A++++A+++++++++++ 

+++++++++++++A+++++++++++ 

++++++++A++++A+++++++++++ 

Serosa, cholangiocarcinoma, 

metastatic, liver X 

Heart 

Cardiovascular System 

Tooth 

Stomach, glandular ++++++++A++++A+++++++++++ 

++++M++++++++++++++++++++ 

Neoplasm NOS, metastatic, 

uncertain primary site X 

Epicardium, cholangiocarcinoma, 

metastatic, liver X 
Lesions in Female Mice 269 

0.25 mg/m3 (continued) 

Individual Animal Tumor Pathology of Female Mice in the 2-Year Inhalation Study of Nickel Sulfate Hexahydrate: 

TABLE D2 

Number of Days on Study 

0000001111111111222233333 

3333333333333333333333333 

7771777777777777777177117 

Carcass ID Number 

9242584631401571250459886 

8990114456677890579044567 

2223332222222223222322222 

Gallbladder 

Esophagus 

Alimentary System 

Intestine large, cecum 

Intestine large, rectum 

Intestine large, colon 

~~~~~~ 

Wall, cholangiocarcinoma, metastatic, liver 

Lymphatic, cholangiocarcinoma, 

Anus, squamous cell papilloma 

Histiocytic sarcoma 

Intestine small, duodenum 

metastatic, liver 

Intestine small, jejunum 

metastatic, liver 

Serosa, cholangiocarcinoma, 

Liver 

Intestine small, ileum 

Histiocytic sarcoma 

Pheochromocytoma malignant, 

Histiocytic sarcoma 

Hepatocellular adenoma, multiple 

Hepatocellular adenoma 

Hepatocellular carcinoma, multiple 

Hepatocellular carcinoma 

Cholangiocarcinoma 

metastatic, adrenal medulla 

Salivary glands 

Pancreas 

Mesentery 

Serosa, cholangiocarcinoma, 

Squamous cell papilloma 

Histiocytic sarcoma 

Stomach, forestomach 

Cholangiocarcinoma, metastatic, liver 

Cholangiocarcinoma, metastatic, liver 

metastatic, liver 

Tooth 

Stomach, glandular 

......................... 

......................... 

......................... 

......................... 

......................... 

......................... X 

......................... X 

......................... 

......................... 

xx 

X xx xx 

X 

X 

X xx 

X 

......................... 

......................... 

......................... 

X 

X 

......................... ++ 

Heart 

Cardiovascular System 

Epicardium, cholangiocarcinoma, 

Neoplasm NOS, metastatic, 

metastatic, liver 

uncertain primary site 

......................... 
270 Nickel Sulfate Hexahydrate, NTP TR 454 

TABLE D2 

0.25 mg/m3 (continued) 

Individual Animal Tumor Pathology of Female Mice in the Inhalation Study of Nickel Sulfate Hexahydrate: 

3333366666 

3333333333 

1111111111 

Number of Days on Study 

Carcass ID Number 

9182991941 

I991158911 

2223322233 

Tumors 

Tissues/ 

Total 

Gallbladder 

Esophagus 

Alimentary System 

Intestine large, cecum 

Intestine large, rectum 

Intestine large, colon 

Wall, cholangiocarcinoma, metastatic, liver 

Lymphatic, cholangiocarcinoma, 

Anus, squamous cell papilloma 

Histiocytic sarcoma 

Intestine small, duodenum 

metastatic, liver 

Intestine small, jejunum 

metastatic, liver 

Serosa, cholangiocarcinoma, 

Liver 

Intestine small, ileum 

Histiocytic sarcoma 

Pheochromocytoma malignant, 

Histiocytic sarcoma 

Hepatocellular adenoma, multiple 

Hepatocellular adenoma 

Hepatocellular carcinoma, multiple 

Hepatocellular carcinoma 

Cholangiocarcinoma 

metastatic, adrenal medulla 

Salivary glands 

Pancreas 

Mesentery 

Serosa, cholangiocarcinoma, 

Squamous cell papilloma 

Histiocytic sarcoma 

Stomach, forestomach 

Cholangiocarcinoma, metastatic, liver 

Cholangiocarcinoma, metastatic, liver 

metastatic, liver 

Tooth 

Stomach, glandular 

++++++++++ 

+.+++++++++ 

+++++++M++ 

++++++++++ 

++++++++++ 

++M+++++++ 

++++++++++ 

++++++++++ 

++++++++++ 

xx X 

X 

++++++++++ 

++++++++++ 

++++++++++ 

++++++++++ 

57 

1 

57 

51 

1 

55 

59 

1 

SI 

1 

2 

1 

13 

5 

9 

1 

59 

58 

1 

58 

1 

1 

4 

1 

1 

1 

58 

59 

1 

58 

2 

58 

1 

Heart 

Cardiovascular System 

Epicardium, cholangiocarcinoma, 

Neoplasm NOS, metastatic, 

metastatic, liver 

uncertain primary site 

++++++++++ 

1 

1 

59 
Lesions in Female Mice 271 

0.25 mg/m3 (continued) 

Individual Animal Tumor Pathology of Female Mice in the 2-Year Inhalation Study of Nickel Sulfate Hexahydrate: 

TABLE D2 

Number of Days on Study 

4158319884459629731580000 

1679815781234677801223333 

0333455556666666677777777 

Carcass ID Number 

2795778166337600326187030 

6500078805976626481444568 

2233322232222232223222222 

Adrenal cortex 

Endocrine System 

Extra adrenal tissue, cholangiocarcinoma, 

metastatic, liver 

Adrenal medulla 

Pheochromocytoma benign 

Pheochromocytoma malignant 

Cholangiocarcinoma, metastatic, liver 

Adenoma 

Islets, pancreatic 

Thyroid gland 

Pituitary gland 

Parathyroid gland 

Follicular cell, adenoma, multiple 

Pars distalis, adenoma 

++++++++++++IA+++++++++++ 

X 

+++++I ++++++I A+++++++++++ 

X 

X 

++++++++A++++A+++++++++++ 

X 

++++M++++++++++++++++++++ 

X 

+++++++M+++++A++++++I++++ 

+++MM+++M+MMMMM+I++M+++++ 

X X 

Tissue NOS 

General Body System 

Thoracic, neoplasm NOS, metastatic, 

Mediastinum, cholangiocarcinoma, 

uncertain primary site 

metastatic, liver 

++ 

X 

X 

+ 

Ovary 

Clitoral gland 

Genital System 

+++++++++++++A+++++++++++ 

I++++++++++++++++++++++++ 

Bilateral, cholangiocarcinoma, 

Granulosa cell tumor malignant 

Cystadenoma 

metastatic, liver 

Uterus 

Polyp stromal, multiple 

Polyp stromal 

Histiocytic sarcoma 

Fibroma 

Cholangiocarcinoma, metastatic, liver X 

X 

......................... 

X 

X 

X 

Histiocytic sarcoma 

Bone marrow 

Hematopoietic System 

Renal, histiocytic sarcoma 

Inguinal, histiocytic sarcoma 

Iliac, histiocytic sarcoma 

Lymph node 

+++++++++++++A+++++++++++ 

X 

X 

+ 

X 

+ ++ + 
272 Nickel Sulfate Hexahydrate, NTP TR 454 

Number of Days on Study 

0000001111111111222233333 

3333333333333333333333333 

7777777777777777777777777 

9242584631401571250459886 

8990114456677890579044567 

2223332222222223222322222 

Carcass ID Number 

Adrenal cortex 

Endocrine System 

~ ~~~~~~~~~~~~~~~~~~~~ ~ ~~ ~ ~~ ~ ~ ~ 

......................... Extra adrenal tissue, cholangiocarcinoma, 

metastatic, liver 

Adrenal medulla 

Pheochromocytoma benign 

Pheochromocytoma malignant 

Cholangiocarcinoma, metastatic, liver 

Adenoma 

Islets, pancreatic 

Thyroid gland 

Pituitary gland 

Parathyroid gland 

Follicular cell, adenoma, multiple 

Pars distalis, adenoma 

......................... 

++++++++++++++++I++++++++ 

++++++M++++++++++++++++++ 

+++MM+++M++++++++M+++++M+ 

X X X X xx ......................... X 

Tissue NOS 

General Body System 

+ + + 

Thoracic, neoplasm NOS, metastatic, 

Mediastinum, cholangiocarcinoma, 

uncertain primary site 

metastatic, liver 

Ovary 

Clitoral gland 

Genital System 

+++++++++++M+++++++++++++ 

........................ 

Bilateral, cholangiocarcinoma, 

Granulosa cell tumor malignant 

Cystadenoma 

metastatic, liver 

Uterus ......................... 

Polyp stromal, multiple 

Polyp stromal 

Histiocytic sarcoma 

Fibroma 

Cholangiocarcinoma, metastatic, liver 

Histiocytic sarcoma 

Bone marrow 

Hematopoietic System 

Renal, histiocytic sarcoma 

Inguinal, histiocytic sarcoma 

Iliac, histiocytic sarcoma 

Lymph node 

X 

X 

......................... 

++ + + + 

X 
Lesions in Female Mice 273 

0.25 mg/m3 (continued) 

Individual Animal Tumor Pathology of Female Mice in the 2-Year Inhalation Study of Nickel Sulfate Hexahydrate: 

TABLE D2 

3333366666 

3333333333 

7717117777 

9182991941 

7991158911 

2223322233 

Number of Days on Study 

Tumors 

Tissues/ 

Total 

Carcass ID Number 

Adrenal cortex 

Endocrine System 

Extra adrenal tissue, cholangiocarcinoma, 

metastatic, liver 

Adrenal medulla 

Pheochromocytoma benign 

Pheochromocytoma malignant 

Cholangiocarcinoma, metastatic, liver 

Adenoma 

Islets, pancreatic 

Thyroid gland 

Pituitary gland 

Parathyroid gland 

Follicular cell, adenoma, multiple 

Pars distalis, adenoma 

++++++++++ 

++++++++++ 

++++M+++++ 

X 

++++++++++ 

M+++++++++ 

++++++++++ 

58 

1 

59 

9 

56 

44 

1 

1 

56 

1 

1 

57 

1 

Tissue NOS 

General Body System 

Thoracic, neoplasm NOS, metastatic, 

Mediastinum, cholangiocarcinoma, 

uncertain primary site 

metastatic, liver 

+ t 

Ovary 

Clitoral gland 

Genital System 

Bilateral, cholangiocarcinoma, 

Granulosa cell tumor malignant 

Cystadenoma 

metastatic, liver 

uterus 

Polyp stromal, multiple 

Polyp stromal 

Histiocytic sarcoma 

Fibroma 

Cholangiocarcinoma, metastatic, 

++++++++++ 

+M++++++++ 

X 

X 

++++++++++ 

liver 

1 

1 

58 

56 

1 

2 

1 

1 

1 

60 

1 

Histiocytic sarcoma 

Bone marrow 

Hematopoietic System 

Renal, histiocytic sarcoma 

Inguinal, histiocytic sarcoma 

Iliac, histiocytic sarcoma 

Lymph node 

++++++++++ 

4- 

1 

1 

1 

11 

1 

59 
274 Nickel Sulfate Hexahydrate, NTP TR 454 

TABLE D2 

0.25 mgh3 (continued) 

Individual Animal Tumor Pathology of Female Mice in the 2-Year Inhalation Study of Nickel Sulfate Hexahydrate: 

4158319884459629731580000 

1679815781234677801223333 

0333455556666666677777777 

Number of Days on Study 

Carcass ID Number 

2795778166337600326187030 

6500078805976626481444568 

2233322232222232223222222 

Lymph node, bronchial 

Hematopoietic System (continued) 

M+++M++++++++A+++++++++++ 

Cholangiocarcinoma, metastatic, liver X 

Neoplasm NOS, metastatic, 

Histiocytic sarcoma 

uncertain primary site 

Lymph node, mesenteric 

Histiocytic sarcoma 

Lymph node, mandibular 

Histiocytic sarcoma 

Cholangiocarcinoma, metastatic, liver 

Neoplasm NOS, metastatic, 

Histiocytic sarcoma 

Cholangiocarcinoma, metastatic, liver 

Lymph node, mediastinal 

uncertain primary site 

Spleen 

metastatic, liver 

Capsule, cholangiocarcinoma, 

Histiocytic sarcoma 

Thymus 

Neoplasm NOS, metastatic, 

Cholangiocarcinoma, metastatic, liver 

uncertain primary site 

X 

X 

++++M++I +++++A+I +++++++++ 

X 

++++++++A+A++AI +++++A++++ 

X 

X 

MMM+MM+++M+MMMMM+++++M+MM 

X 

X 

X 

++++++++++A++A+++++++++++ 

X 

X 

+IM++++++++++A+++++++++++ 

X 

X 

Integumentary System 

Fibroadenoma 

Carcinoma 

Mammary gland 

Subcutaneous tissue, hemangioma 

Squamous cell papilloma 

~~ 

++++++++++++IA+++++++++++ 

X 

Skin ......................... 

X 

Skeletal muscle 

Bone 

Musculoskeletal System 

Neoplasm NOS, metastatic, 

uncertain primary site 

......................... ++ 

X 

+ 

Diaphragm, cholangiocarcinoma, 

Abdominal, cholangiocarcinoma, 

metastatic, liver 

metastatic, liver X 

X 

Brain 

Nervous System 

+++++++++++++A+++++++++++ 
Lesions in Female Mice 275 

0.25 mg/m’ (continued) 

Individual Animal Tumor Pathology of Female Mice in the 2-Year Inhalation Study of Nickel Sulfate Hexahydrate: 

TABLE D2 

Number of Days on Study 

0000001111111111222233333 

3333333333333333333333333 

7777777777777777777777777 

Carcass ID Number 

9242584631401571250459886 

8990114456677890579044567 

2223332222222223222322222 

Lymph node, bronchial 

Hematopoietic System (continued) 

......................... 

Neoplasm NOS, metastatic, 

Histiocytic sarcoma 

Cholangiocarcinoma, metastatic, liver 

uncertain primary site 

Lymph node, mesenteric 

Histiocytic sarcoma 

Lymph node, mandibular 

Histiocytic sarcoma 

Cholangiocarcinoma, metastatic, liver 

Neoplasm NOS, metastatic, 

Histiocytic sarcoma 

Cholangiocarcinoma, metastatic, liver 

Lymph node, mediastinal 

uncertain primary site 

Spleen 

metastatic, liver 

Capsule, cholangiocarcinoma, 

Histiocytic sarcoma 

Thymus 

Neoplasm NOS, metastatic, 

Cholangiocarcinoma, metastatic, liver 

uncertain primaIy site 

......................... 

++++++++++++M++I ++++++I ++ 

M++MM++++++M++MMI+MMM+MMM 

......................... X 

+++++++++I++++++++M++++++ 

Mammary gland 

Integumentary System ......................... 

Subcutaneous tissue, hemangioma 

Squamous cell papilloma 

Fibroadenoma 

Carcinoma 

X 

Skin ......................... X 

Skeletal muscle 

Bone 

Musculoskeletal System 

......................... 

Diaphragm, cholangiocarcinoma, 

Abdominal, cholangiocarcinoma, 

Neoplasm NOS. metastatic, 

metastatic, liver 

metastatic, liver 

uncertain primary site 

Brain 

Nervous System 

......................... 
276 Nickel Sulfate Hexahydrate, NTP TR 454 

0.25 mg/m3 (continued) 

Individual Animal Tumor Pathology of Female Mice in the 2-Year Inhalation Study of Nickel Sulfate Hexahydrate: 

TABLE D2 

3333366666 

3333333333 

7777777777 

Number of Days on Study 

Carcass ID Number 

9182997947 

7991158911 

2223322233 

Tumors 

Tissues/ 

Total 

Lymph node, bronchial 

Hematopoietic System (continued) 

~~ ____ ____ 

++I +++++++ 

Neoplasm NOS, metastatic, 

Histiocytic sarcoma 

Cholangiocarcinoma, metastatic, liver 

uncertain primary site 

Lymph node, mesenteric 

Histiocytic sarcoma 

Lymph node, mandibular 

Histiocytic sarcoma 

Cholangiocarcinoma, metastatic, liver 

Neoplasm NOS, metastatic, 

Histiocytic sarcoma 

Cholangiocarcinoma, metastatic, liver 

Lymph node, mediastinal 

++++++++++ 

++++++++++ 

++MM++MM+M 

1 

1 

54 

1 

1 

28 

1 

1 

52 

1 

56 

1 

uncertain primary site 

2 

58 

1 

Spleen ++++++++++ 

metastatic, liver 

Capsule, cholangiocarcinoma, 

Histiocytic sarcoma 

1 

54 

1 

Thymus M+++++++++ 

Neoplasm NOS, metastatic, 

Cholangiocarcinoma, metastatic, liver 

Integumentary System 

uncertain primary site 

Fibroadenoma 

Carcinoma 

Mammary gland 

Subcutaneous tissue, hemangioma 

Squamous cell papilloma 

1 

++++++++++ 

1 

1 

58 

1 

1 

Skin ++++++++I + 59 

Skeletal muscle 

Bone 

Musculoskeletal System 

++++++++++ 

1 

3 

60 

Diaphragm, cholangiocarcinoma, 

Abdominal, cholangiocarcinoma, 

Neoplasm NOS, metastatic, 

metastatic, liver 

metastatic, liver 

uncertain primary site 

1 

1 

Brain 

Nervous System 

++++++++++ 59 
Lesions in Female Mice 277 

0.25 mg/m3 (continued) 

Individual Animal Tumor Pathology of Female Mice in the 2-Year Inhalation Study of Nickel Sulfate Hexahydrate: 

TABLE D2 

Number of Days on Study 

4158319884459629731580000 

1679815781234677801223333 

0333455556666666677771777 

Carcass ID Number 

2795778166331600326187030 

6500078805976626481444568 

2233322232222232223222222 

Lung 

Larynx 

Respiratory System 

~ ~ ______~~ 

Neoplasm NOS, metastatic, 

Histiocytic sarcoma 

Hepatocellular carcinoma, metastatic, liver 

Hepatocellular carcinoma, metastatic 

Cholangiocarcinoma, metastatic, liver 

Alveolarlbronchiolar carcinoma 

Alveolar/bronchiolar adenoma 

uncertain primary site 

Trachea 

Nose 

......................... 

+++I M++M++++I ++++++++++++ 

xx 

X 

X 

X 

X X 

X 

X 

......................... 

+++++++++++++A+++++++++++ 

~~ 

Harderian gland 

Ear 

Special Senses System 

Adenoma 

~~~ ~ 

+ 

X 

+ 

Wdney 

Urinary System ......................... 

metastatic, liver 

Perirenal tissue, cholangiocarcinoma, 

Histiocytic sarcoma X 

X 

Urinaj bladder ......................... Serosa, cholangiocarcinoma, 

metastatic, liver X 

Multiple organs 

Systemic Lesions 

Lymphoma malignant 

Histiocytic sarcoma 

......................... X X 

xx x x X 
278 Nickel Sulfate Hexahydrate, NTP TR 454 

0.25 mg/m3 (continued) 

Individual Animal Tumor Pathology of Female Mice in the 2-Year Inhalation Study of Nickel Sulfate Hexahydrate: 

TABLE D2 

0000001111111111222233333 

3333333333333333333333333 

7777777777777777777777777 

Number of Days on Study 

Carcass ID Number 

9242584631401571250459886 

8990114456677890579044567 

2223332222222223222322222 

Lung 

Larynx 

Respiratory System 

......................... 

......................... 

Neoplasm NOS, metastatic. 

Histiocytic sarcoma 

Hepatocellular carcinoma, metastatic, liver 

Hepatocellular carcinoma, metastatic 

Cholangiocarcinoma, metastatic, liver 

Alveolarlbronchiolar carcinoma 

Alveolar/bronchiolar adenoma 

X X 

uncertain primary site 

Trachea 

Nose 

Harderian gland 

Ear 

Special Senses System 

Adenoma 

......................... 

......................... 

X 

+ 

Kidney 

Urinary System 

......................... 

metastatic, liver 

Perirenal tissue, cholangiocarcinoma, 

Histiocytic sarcoma 

Urinary bladder ......................... Serosa, cholangiocarcinoma, 

Multiple organs 

Systemic Lesions 

metastatic, liver 

......................... 

Lymphoma malignant 

Histiocytic sarcoma X 

xx X 

X 

xx 
Lesions in Female Mice 279 

0.25 mg/d (continued) 

Individual Animal Tumor Pathology of Female Mice in the 2-Year Inhalation Study of Nickel Sulfate Hexahydrate: 

TABLE D2 

Number of Days on Study 

3333366666 

3333333333 

7771777777 

9182997947 

7991158911 

2223322233 

Tumors 

Tissues1 

Total 

Carcass ID Number 

Lung 

Larynx 

Respiratory System 

Hepatocellular carcinoma, metastatic 

Cholangiocarcinoma, metastatic, liver 

Alveolar/bronchiolar carcinoma 

Alveolar/bronchiolar adenoma 

++++++++++ 

++++++++++ 

X 

Neoplasm NOS, metastatic, 

Histiocytic sarcoma 

Hepatocellular carcinoma, metastatic, liver 

uncertain primary site 

Trachea 

Nose 

++++++++++ 

++++++++++ 

1 

2 

1 

1 

3 

3 

60 

56 

60 

59 

1 

Harderian gland 

Ear 

Special Senses System 

Adenoma 2 

2 

1 

Kidney 

Urinary System 

++++++++++ 

metastatic, liver 

Perirenal tissue, cholangiocarcinoma, 

Histiocytic sarcoma 

Urinary bladder ++++++++++ 

Serosa, cholangiocarcinoma, 

metastatic, liver 

1 

60 

60 

1 

1 

Multiple organs 

Systemic Lesions 

Lymphoma malignant 

Histiocytic sarcoma 

++++++++++ 

X X 12 

4 

60 
280 Nickel Sulfate Hexahydrate, NTP TR 454 

TABLE D2 

0.5 mg/m3 

Individual Animal Tumor Pathology of Female Mice in the 2-Year Inhalation Study of Nickel Sulfate Hexahydrate: 

4409774996221140000000000 

3513671245778813333333333 

3455556666666677777777777 

8471849829998975601255824 

1513527753126650011112247 

4444444444444444444444444 

Number of Days on Study 

Carcass ID Number 

Intestine small, duodenum 

Intestine large, cecum 

Intestine large, rectum 

Intestine large, colon 

Gallbladder 

Esophagus 

Alimentary System 

Liver 

Intestine small, ileum 

Intestine small, jejunum 

Adenocarcinoma 

Hepatocellular adenoma 

Hepatocellular carcinoma 

++++A++++++++++++++++++++ 

......................... 

+++++++++I+++++++++++++++ 

......................... 

++++MM+++++++M+++++++++++ 

......................... 

......................... 

++++A++++++++++++++++++++ 

++++A++++++++++++++++++++ 

X xx X X 

X X X 

Histiocytic sarcoma 

Carcinoma, metastatic, lung 

Histiocytic sarcoma 

Hepatocellular adenoma, multiple 

X 

++ 

X 

Mesentery 

X 

+ + 

Pancreas ......................... 

Stomach, glandular 

Stomach, forestomach 

Salivary glands 

Histiocytic sarcoma 

Tooth 

Carcinoma, metastatic, lung 

+++++M+++++++++++++++++++ 

......................... 

......................... 

X 

Heart 

Cardiovascular System ......................... Carcinoma, metastatic, lung X 

Adrenal cortex 

Endocrine System ......................... 

Extra adrenal tissue, histiocytic sarcoma 

Extra adrenal tissue, carcinoma, 

metastatic, lung X 

X 

Islets, pancreatic 

Adrenal medulla 

++++++++++++++I++++++++++ 

......................... 

Pituitary gland 

Parathyroid gland 

Adenoma 

Follicular cell, adenoma 

Pars intermedia, adenoma 

Pars distalis, adenoma 

Thyroid gland 

+++++M+++++++++++++++++++ 

++M++++++M+M+M+MM++++M+++ 

X 

x ......................... 

Tissue NOS 

General Body System 

X 

+ + + 

Thoracic, carcinoma, metastatic, lung 

Mediastinum, carcinoma, metastatic, lung 

Fibrosarcoma, metastatic, skin 

X 

X 
Lesions in Female Mice 281 

0.5 mg/m3 (continued) 

Individual Animal Tumor Pathology of Female Mice in the 2-Year Inhalation Study of Nickel Sulfate Hexahydrate: 

TABLE D2 

Number of Days on Study 

1111111222222222333333366 

3333333333333333333333333 

7777777777777777777777777 

Carcass ID Number 

4444444.444444444444444444 

3750965183432330467153721 

0034451001123478022445702 

Intestine small, duodenum 

Intestine large, cecum 

Intestine large, rectum 

Intestine large, colon 

Gallbladder 

Esophagus 

Alimentary System 

Liver 

Intestine small, ileum 

Intestine small, jejunum 

Adenocarcinoma 

Histiocytic sarcoma 

Hepatocellular adenoma, multiple 

Hepatocellular adenoma 

Hepatocellular carcinoma 

Pancreas 

Histiocytic sarcoma 

Carcinoma, metastatic, lung 

Stomach, glandular 

Stomach, forestomach 

Salivary glands 

Histiocytic sarcoma 

Tooth 

Mesentery 

Carcinoma, metastatic, lung 

......................... 

......................... 

++++I++++++M+++++++++++++ 

++++M+++++++++++++M++++++ 

......................... 

+++++I+++++++++++++++++++ 

......................... 

......................... 

......................... 

X X 

X X xx 

X 

X 

......................... 

......................... 

......................... 

X 

......................... 

+ 

Heart 

Cardiovascular System 

Carcinoma, metastatic, lung 

......................... 

Adrenal cortex 

Endocrine System 

Extra adrenal tissue, histiocytic sarcoma 

Extra adrenal tissue, carcinoma, 

metastatic, lung 

Adenoma 

Islets, pancreatic 

Adrenal medulla 

Pituitary gland 

Parathyroid gland 

Follicular cell, adenoma 

Pars intermedia, adenoma 

Pars distalis, adenoma 

Thyroid gland 

......................... 

......................... 

+++++++++M+++++++++++M+++ 

......................... 

......................... 

X 

xx X 

......................... X 

~ ~~ ~~~~~~~ 

Tissue NOS 

General Body System 

Thoracic, carcinoma, metastatic, lung 

Mediastinum, carcinoma, metastatic, lung 

Fibrosarcoma, metastatic, skin 
282 Nickel Sulfate Hexahydrate, NTP TR 454 

0.5 mg/m3 (continued) 

Individual Animal Tumor Pathology of Female Mice in the 2-Year Inhalation Study of Nickel Sulfate Hexahydrate: 

TABLE D2 

3333333333 

7777777777 

Number of Days on Study 

6666666666 

20780'50726 

2344556677 

4444444444 

Carcass ID Number 

Tumors 

Tissues1 

Total 

Gallbladder 

Esophagus 

Alimentary System 

++++++++++ 

57 

59 

++++++++++ 

Intestine small, duodenum 

Intestine large, cecum 

Intestine large, rectum 

Intestine large, colon 

Liver 

Intestine small, ileum 

Intestine small, jejunum 

Adenocarcinoma 

Histiocytic sarcoma 

Hepatocellular adenoma, multiple 

Hepatocellular adenoma 

Hepatocellular carcinoma 

Pancreas 

Histiocytic sarcoma 

Carcinoma, metastatic, lung 

Stomach, glandular 

Stomach, forestomach 

Salivary glands 

Histiocytic sarcoma 

Tooth 

Mesentery 

Carcinoma, metastatic, lung 

++++++++++ 

++++++++++ 

M++++++++I 

++++++++++ 

X 

++++++++++ 

++++++M+++ 

++++++++++ 

X 

++++++++++ 

++++++++++ 

++++++++++ 

++++++++++ 

59 

60 

55 

58 

1 

1 

4 

2 

1 

10 

5 

60 

58 

59 

1 

1 

1 

59 

60 

60 

1 

60 

Heart 

Cardiovascular System 

++++++++++ 

1 

60 

Carcinoma, metastatic, lung 

Adrenal cortex 

Endocrine System 

++++++++++ 60 

Extra adrenal tissue. histiocytic sarcoma 

Extra adrenal tissue, carcinoma, 

metastatic, lung 

Islets, pancreatic 

Adrenal medulla 

++++++++++ 

++++++++++ 

Pituitary gland 

Parathyroid gland 

Adenoma 

Follicular cell, adenoma 

Pars intermedia, adenoma 

Pars distalis, adenoma 

Thyroid gland 

++++++++++ 

++++++M+++ 

X 

++++++++++ 

2 

60 

1 

5 

59 

50 

1 

59 

60 

1 

1 

Tissue NOS 

General Body System 

+ 

1 

1 

1 

4 

Thoracic, carcinoma, metastatic, lung 

Mediastinum, carcinoma, metastatic, lung 

Fibrosarcoma, metastatic, skin 
Lesions in Female Mice 283 

0.5 mg/m3 (continued) 

Individual Animal Tumor Pathology of Female Mice in the 2-Year Inhalation Study of Nickel Sulfate Hexahydrate: 

TABLE D2 

4409774996221140000000000 

3513671245778813333333333 

3455556666666677777777777 

8471849829998975601255824 

1513527753126650011112247 

4444444444444444444444444 

Number of Days on Study 

Carcass ID Number 

Ovary 

Clitoral gland 

Genital System 

Uterus 

~~ 

Histiocytic sarcoma 

Leiomyosarcoma 

Histiocytic sarcoma 

Hemangioma 

Fibroma 

Vagina 

......................... 

++I+M+++++++++++M++++M+++ 

X 

......................... 

X 

X 

Bone marrow 

Hematopoietic System 

......................... Lyfnph node 

Renal, histiocytic sarcoma 

Pancreatic, neoplasm NOS 

Pancreatic, histiocytic sarcoma 

Pancreatic, carcinoma, metastatic, lung 

Inguinal, carcinoma, metastatic, lung 

Iliac, histiocytic sarcoma 

Axillary, carcinoma, metastatic, lung 

Histiocytic sarcoma 

Carcinoma, metastatic, lung 

Lymph node, bronchial 

Lymph node, mesenteric 

Histiocytic sarcoma 

Lymph node, mandibular 

Histiocytic sarcoma 

Carcinoma, metastatic, lung 

Histiocytic sarcoma 

Carcinoma, metastatic, lung 

Lymph node, mediastinal 

Histiocytic sarcoma 

Thymus 

Spleen 

X 

+++ + + + 

X 

X 

X 

+++++I++M++++++++++++++++ 

X 

......................... X 

++++++++++I++++++++++++++ 

X 

X 

+MM++++MI+MM+M+++MMM+++++ 

X 

......................... 

++++++++++++++++M++++++++ 

Skin 

Mammary gland 

Integumentary System 

Subcutaneous tissue, fibrosarcoma 

Subcutaneous tissue, carcinoma, 

metastatic, lung 

++++++++++++++++++++++I++ 

......................... 

X 

X 

Skeletal muscle 

Bone 

Musculoskeletal System 

......................... 

Abdominal, carcinoma, metastatic, lung 

Maxilla, histiocytic sarcoma X 

+ 

X 

+ + 
284 Nickel Sulfate Hexahydrate, NTP TR 454 

TABLE D2 

0.5 mgh’ (continued) 

Individual Animal Tumor Pathology of Female Mice in the 2-Year Inhalation Study of Nickel Sulfate Hexahydrate: 

3333333333333333333333333 

7777777777177777717777177 

Number of Days on Study 

1111111222222222333333366 

4444444444444444444444444 

Carcass ID Number 

3750965183432330461153721 

0034457001123478022445702 

Ovary 

Clitoral gland 

Genital System 

Uterus ......................... 

......................... 

+++++++++++M+++++++M++++M 

Histiocytic sarcoma 

Leiomyosarcoma 

Histiocytic sarcoma 

Hemangioma 

Fibroma 

Vagina 

Lymph node 

Bone marrow 

Hematopoietic System 

+ + ......................... +++ + 

Inguinal, carcinoma, metastatic, lung 

Iliac, histiocytic sarcoma 

Axillary, carcinoma, metastatic, lung 

X 

Renal, histiocytic sarcoma 

Pancreatic, neoplasm NOS 

Pancreatic, histiocytic sarcoma 

Pancreatic, carcinoma, metastatic, 

Histiocytic sarcoma 

Carcinoma, metastatic, lung 

Lymph node, bronchial 

Lymph node, mesenteric 

Histiocytic sarcoma 

Lymph node, mandibular 

Histiocytic sarcoma 

Carcinoma, metastatic, lung 

Histiocytic sarcoma 

Carcinoma, metastatic, lung 

Lymph node, mediastinal 

Histiocytic sarcoma 

Thymus 

Spleen 

lung 

A 

X 

......................... 

X 

+++++++I+++++++M+++++++++ 

X 

......................... 

X 

++M++MI ++M++++M+I +MM+MMMM 

X 

++++++I+++++++++M++++++++ 

X 

......................... 

X 

Skin 

Mammary gland 

Integumentary System 

Subcutaneous tissue, fibrosarcoma 

Subcutaneous tissue, carcinoma, 

metastatic, fung 

......................... 

......................... 

Skeletal muscle 

Bone 

Musculoskeletal System ......................... 

Abdominal, carcinoma, metastatic, lung 

Maxilla, histiocytic sarcoma 
Lesions in Female Mice 285 

0.5 mg/m3 (continued) 

Individual Animal Tumor Pathology of Female Mice in the 2-Year Inhalation Study of Nickel Sulfate Hexahydrate: 

TABLE 02 

~~ ~~~ 

Number of Days on Study 

6666666666 

3333333333 

1111111111 

~ ~~ ~~ ~ 

Carcass ID Number 

2018050126 

2344556677 

4444444444 

Tumors 

Tissues/ 

Total 

Ovary 

Clitoral gland 

Genital System 

Uterus 

Histiocytic sarcoma 

Leiomyosarcoma 

Histiocytic sarcoma 

Hemangioma 

Fibroma 

Vagina 

++++++++++ 

++M+++++++ 

++++++++++ 

X 

X 

+ 

1 

1 

1 

1 

1 

60 

1 

60 

52 

Lymph node 

Bone marrow 

Hematopoietic System 

++++++++++ 

1 

13 

60 

+ 

Renal, histiocytic sarcoma 

Pancreatic, neoplasm NOS 

Pancreatic, histiocytic sarcoma 

Pancreatic, carcinoma, metastatic, lung 

Inguinal, carcinoma, metastatic, lung 

Iliac, histiocytic sarcoma 

Axillary, carcinoma, metastatic, lung 

Histiocytic sarcoma 

Carcinoma, metastatic, lung 

Lymph node, bronchial 

Lymph node, mesenteric 

Histiocytic sarcoma 

Lymph node, mandibular 

Histiocytic sarcoma 

Carcinoma, metastatic, lung 

Histiocytic sarcoma 

Carcinoma, metastatic, lung 

Lymph node, mediastinal 

Histiocytic sarcoma 

Thymus 

Spleen 

++++++++++ 

++++++++++ 

+++++++M++ 

++M++MM+MM 

++++++++++ 

++M++M+M++ 

2 

1 

1 

1 

1 

1 

2 

1 

56 

2 

60 

1 

1 

58 

1 

1 

33 

54 

1 

60 

Skin 

Mammary gland 

Integumentary System 

Subcutaneous tissue, fibrosarcoma 

Subcutaneous tissue, carcinoma, 

metastatic, lung 

++++++++++ 

++++++++++ 

59 

60 

1 

1 

Skeletal muscle 

Bone 

Musculoskeletal System 

++++++-I-+++ 

Abdominal, carcinoma, metastatic, lung 

Maxilla, histiocytic sarcoma 

1 

3 

1 

60 
286 Nickel Sulfate Hexahydrate, NTP TR 454 

0.5 mg/m3 (continued) 

Individual Animal Tumor Pathology of Female Mice in the 2-Year Inhalation Study of Nickel Sulfate Hexahydrate: 

TABLE D2 

4409774996221140000000000 

3513671245778813333333333 

3455556666666677777777777 

8471849829998975601255824 

1513527753126650011112247 

4444444444444444444444444 

Number of Days on Study 

Carcass ID Number 

Brain 

Nervous System 

Lung 

Larynx 

Respiratory System 

++++++M++++++++++++++++++ 

......................... 

......................... 

X X 

......................... 

......................... 

Alveolar/bronchiolar carcinoma, multiple 

Alveolarbronchiolar carcinoma 

Alveolar/bronchiolar adenoma 

X 

Trachea 

Nose 

Harderian gland 

Ear 

Special Senses System 

Zymbal’s gland 

Lacrimal gland 

Adenoma 

Carcinoma 

xx 

++ 

X 

+ 

+ 

~ ~ ~~ 

Kidnev 

Urinary System ......................... Histiocytic sarcoma X 

Multiple organs 

Systemic Lesions 

Urinary bladder +++++++++++++A+++++++++++ 

......................... 

Lymphoma malignant 

Histiocytic sarcoma 

xx 

X 

X 
Lesions in Female Mice 

TABLE D2 

287 

0.5 mg/m3 (continued) 

Individual Animal Tumor Pathology of Female Mice in the 2-Year Inhalation Study of Nickel Sulfate Hexahydrate: 

1111111222222222333333366 

3333333333333333333333333 

7777777777777777777777777 

3750965183432330467153721 

0034457001123478022445702 

4444444444444444444444444 

Number of Days on Study 

Carcass ID Number 

Brain 

Nervous System 

Lung 

Larynx 

Respiratory System 

......................... 

......................... 

+++++I+++++++++++++++++++ 

Alveolarlbronchiolar carcinoma, multiple 

Alveolar/bronchiolar carcinoma 

Alveolarlbronchiolar adenoma 

X 

X 

X X 

Trachea 

Nose 

Harderian gland 

Ear 

Special Senses System 

Zymbal’s gland 

Lacrimal gland 

Adenoma 

Urinary System 

Carcinoma 

Systemic Lesions 

Urinary bladder 

Kidney 

Multiple organs 

......................... 

......................... 

+ 

+++++++++M+++++++++++++++ 

X 

......................... Histiocytic sarcoma 

X 

......................... 

Lymphoma malignant 

Histiocytic sarcoma 

X X X xx 

X 

+ 

X 

+ 
288 Nickel Sulfate Hexahydrate, NTP TR 454 

0.5 l"lg/m3 (continued) 

Individual Animal Tumor Pathology of Female Mice in the 2-Year Inhalation Study of Nickel Sulfate Hexahydrate: 

TABLE D2 

6666666666 

3333333333 

7777777777 

2018050726 

2344556677 

4444444444 

Number of Days on Study 

Tumors 

Tissues1 

Total 

Carcass ID Number 

Brain 

Nervous System 

Lung 

Larynx 

Respiratory System 

++++++++++ 59 

X 

++++++++++ 

++I +++++++ 

60 

60 

1 

8 

2 

60 

58 

Alveolar/bronchiolar carcinoma, multiple 

Alveolar/bronchiolar carcinoma 

Alveolar/bronchiolar adenoma 

X xx 

Trachea 

Nose 

Harderian gland 

Ear 

Special Senses System 

Zymbal's gland 

Lacrimal gland 

Adenoma 

Urinary System 

Carcinoma 

Systemic Lesions 

Urinary bladder 

Kidney 

Multiple organs 

++++++++++ 

++++++++++ 

+ 

1 

1 

1 

4 

4 

2 

++++++++++ 

58 

2 

60 

Histiocytic sarcoma 

++++++++++ 

++++++++++ 

9 

2 

60 

Lymphoma malignant 

Histiocytic sarcoma 

X 
Lesions in Female Mice 289 

1 mg/m3 

Individual Animal Tumor Pathology of Female Mice in the 2-Year Inhalation Study of Nickel Sulfate Hexahydrate: 

TABLE D2 

1010373612216149959834800 

8167956126679005677911233 

2333344555555666666677777 

4214353781658561676948034 

8180973009011013926076989 

5656556665666666565655555 

Number of Days on Study 

Carcass ID Number 

Liver 

Intestine small, ileum 

Intestine small, jejunum 

Intestine small, duodenum 

Intestine large, cecum 

Intestine large, rectum 

Intestine large, colon 

Gallbladder 

Esophagus 

Alimentary System 

Osteosarcoma, metastatic, bone 

Histiocytic sarcoma 

Hepatocellular adenoma, multiple 

Hepatocellular adenoma 

Hepatocellular carcinoma, multiple 

Hepatocellular carcinoma 

Hemangiosarcoma 

Carcinoma, metastatic, lung 

Histiocytic sarcoma 

Fibrosarcoma, metastatic, skeletal muscle 

Mesentery 

Tooth 

Stomach, glandular 

Stomach, forestomach 

Salivary glands 

Pancreas 

......................... 

++++++++++A++++++++++++++ 

++++++++++A++++++++++++++ 

++M+++++++A++++++++++++++ 

++++++++++A++++++++++++++ 

++M++++++M++++++I “++I +++ ......................... 

+++++M+AM+A+++++M+++I++++ 

......................... 

X 

X 

xx x x 

X 

xx x 

X 

X xx 

+ + 

X 

......................... 

......................... 

......................... 

......................... 

+ 

Heart 

Cardiovascular System ......................... 

Islets, pancreatic 

Adrenal medulla 

Adrenal cortex 

Endocrine System 

Pituitary gland 

Parathyroid gland 

Adenoma 

Thyroid gland 

Follicular cell, adenoma 

Carcinoma, metastatic, lung 

Pars distalis, adenoma 

......................... 

......................... 

......................... 

++I +++++MI +++++++++++++++ 

+++++MMMMMM+++M++++M++M++ 

X xx ......................... X 

Tissue NOS 

General Body System 

+ 
290 Nickel Sulfate Hexahydrate, NTP TR 454 

TABLE D2 

0001111112222222222223333 

3333333333333333333333333 

7777777777777777777777777 

Number of Days on Study 

8069934473401230681205751 

9228911336677778882236890 

5665566665555555556665556 

Carcass ID Number 

Intestine small, ileum 

Intestine small, jejunum 

Intestine small, duodenum 

Intestine large, cecum 

Intestine large, rectum 

Intestine large, colon 

Gallbladder 

Esophagus 

Alimentary System 

......................... 

......................... 

......................... 

......................... 

+I I ++++++"I ++++++I ++++++ ......................... 

.......................... 

......................... 

Liver ......................... 

Hepatocellular carcinoma, multiple 

Hepatocellular carcinoma 

Hemangiosarcoma 

Carcinoma, metastatic, lung 

X xx 

X 

Osteosarcoma, metastatic, bone 

Histiocytic sarcoma 

Hepatocellular adenoma, multiple 

Hepatocellular adenoma 

Mesentery 

X X 

++ 

X 

Histiocytic sarcoma 

Fibrosarcoma, metastatic, skeletal muscle X 

Tooth 

Stomach, glandular 

Stomach, forestomach 

Salivary glands 

Pancreas 

......................... 

......................... 

......................... 

......................... 

Heart 

Cardiovascular System ......................... 

Adrenal medulla 

Adrenal cortex 

Endocrine System 

......................... 

......................... 

Islets, pancreatic ......................... 

Pituitary gland 

Parathyroid gland 

Adenoma 

Pars distalis, adenoma 

Thyroid gland 

Follicular cell, adenoma 

Carcinoma, metastatic, lung 

X 

.......................... 

++++++++++++++++++I++M+++ 

x ......................... 

X 

Tissue NOS 

General Body System + + 
Lesions in Female Mice 291 

1 mg/m3 (continued) 

Individual Animal Tumor Pathology of Female Mice in the 2-Year Inhalation Study of Nickel Sulfate Hexahydrate: 

TABLE D2 

Number of Days on Study 

3336666666 

3333333333 

7777777777 

Carcass ID Number 

3567782079 

2336779012 

6665555666 

Tumors 

Tissues/ 

Total 

Liver 

Intestine small, ileum 

Intestine small, jejunum 

Intestine small, duodenum 

Intestine large, cecum 

Intestine large, rectum 

Intestine large, colon 

Gallbladder 

Esophagus 

Alimentary System 

Osteosarcoma, metastatic, bone 

Histiocytic sarcoma 

Hepatocellular adenoma, multiple 

Hepatocellular adenoma 

Hepatocellular carcinoma, multiple 

Hepatocellular carcinoma 

Hemangiosarcoma 

Carcinoma, metastatic, lung 

Histiocytic sarcoma 

Fibrosarcoma, metastatic, skeletal muscle 

Mesentery 

Tooth 

Stomach, glandular 

Stomach, forestomach 

Salivary glands 

Pancreas 

++++++++++ 

++++++++++ 

++++++++++ 

++++++++++ 

++++++++++ 

+++++I ++++ 

++++++++++ 

++++++++++ 

++++++++++ 

X 

X X 

+ 

+,+++++++++ 

++++++++++ 

++++++++++ 

+M++++++++ 59 

60 

60 

60 

1 

1 

5 

1 

3 

1 

8 

1 

10 

1 

1 

60 

59 

59 

58 

59 

47 

60 

54 

60 

1 

Heart 

Cardiovascular System 

++++++++++ 60 

Islets, pancreatic 

Adrenal medulla 

Adrenal cortex 

Endocrine System 

Pituitary gland 

Parathyroid gland 

Adenoma 

Thyroid gland 

Follicular cell, adenoma 

Carcinoma, metastatic, lung 

Pars distalis, adenoma 

++++++++++ 

++++++++++ 

++++++++++ 

++++++++++ 

++++++++++ 

++++++++++ 

60 

60 

60 

57 

49 

1 

1 

1 

60 

4 

Tissue NOS 

General Body System 

3 
292 Nickel Sulfate Hexahydrate, NTP TR 454 

1 mg/m3 (continued) 

Individual Animal Tumor Pathology of Female Mice in the 2-Year Inhalation Study of Nickel Sulfate Hexahydrate: 

TABLE D2 

1010373612216149959834800 

8167956126679005677911233 

2333344555555666666677777 

Number of Days on Study 

Carcass ID Number 

4214353781658561676948034 

8180973009011013926076989 

5656556665666666565655555 

Ovary 

Clitoral gland 

Genital System 

+++++++M+++++++++++++++++ 

+++++++++++++++I+++++++++ 

Periovarian tissue, histiocytic sarcoma 

Tubulostromal adenoma 

Granulosa cell tumor benign 

Polyp stromal 

Histiocytic sarcoma 

X 

Uterus ......................... X 

Histiocytic sarcoma 

Bone marrow 

Hematopoietic System 

Renal, histiocytic sarcoma 

Pancreatic, histiocytic sarcoma 

Iliac, histiocytic sarcoma 

Axillary, histiocytic sarcoma 

Lymph node 

Neoplasm NOS, metastatic, lung 

Histiocytic sarcoma 

Carcinoma, metastatic, lung 

Lymph node, bronchial 

Mast cell tumor benign 

Histiocytic sarcoma 

Carcinoma, metastatic 

Lymph node, mandibular 

Lymph node, mediastinal 

Histiocytic sarcoma 

Lymph node, mesenteric 

Carcinoma, metastatic, lung 

Carcinoma, metastatic, lung 

Histiocytic sarcoma 

Histiocytic sarcoma 

Histiocytic sarcoma 

Thymus 

Spleen 

......................... X 

X 

X 

++ ++ + +++ 

X 

X xx 

......................... 

X 

X X 

X 

++++++M+++++++++++MM+++++ 

X 

X X 

++++M+++++M++++M ++++M+++ 

X 

MMMMMMMMI M+++MMM++I MM++MM 

X 

X 

......................... 

......................... X 

X 

X X 

Skin 

Carcinoma 

Mammary gland 

Integumentary System 

......................... 

......................... 

Subcutaneous tissue, hemangioma 

Subcutaneous tissue, fibrosarcoma X 
Lesions in Female Mice 293 

1 mg/m3 (continued) 

Individual Animal Tumor Pathology of Female Mice in the 2-Year Inhalation Study of Nickel Sulfate Hexahydrate: 

TABLE D2 

0001111112222222222223333 

3333333333333333333333333 

7777717777777777777777777 

8069934473401230681205751 

9228911336677778882236890 

566556666555.5555556665556 

Number of Days on Study 

Carcass ID Number 

Ovary 

Clitoral gland 

Genital System 

Periovarian tissue, histiocytic sarcoma 

Tubulostromal adenoma 

Granulosa cell tumor benign 

Polyp stromal 

Histiocytic sarcoma 

Uterus 

......................... 

......................... 

X 

X 

......................... 

X 

Histiocytic sarcoma 

Bone marrow 

Hematopoietic System 

Renal, histiocytic sarcoma 

Pancreatic, histiocytic sarcoma 

Iliac, histiocytic sarcoma 

Axillary, histiocytic sarcoma 

Lymph node 

Neoplasm NOS, metastatic, lung 

Histiocytic sarcoma 

Carcinoma, metastatic, lung 

Lymph node, bronchial 

Mast cell tumor benign 

Histiocytic sarcoma 

Carcinoma, metastatic 

Lymph node, mandibular 

Lymph node, mediastinal 

Histiocytic sarcoma 

Lymph node, mesenteric 

Carcinoma, metastatic, lung 

Carcinoma, metastatic, lung 

Histiocytic sarcoma 

Histiocytic sarcoma 

Histiocytic sarcoma 

Thymus 

Spleen 

~~ ~~~~ 

......................... 

+ + ++ + 

+M+++++++I+++++++++++++++ 

+++++++++++++++++M+++++++ 

X 

+M++++++++++M+M+++++++++M 

I +I I MM++M++I +++I M+MM+I ++M 

+++++++M+++++++++++++++M+ 

......................... 

Carcinoma 

Mammary gland 

Integumentary System 

Subcutaneous tissue, hemangioma 

Subcutaneous tissue, fibrosarcoma 

Skin 

......................... 

......................... X 

X 
294 Nickel Sulfate Hexahydrate, NTP TR 454 

1 mg/m3 (continued) 

Individual Animal Tumor Pathology of Female Mice in the 2-Year Inhalation Study of Nickel Sulfate Hexahydrate: 

TABLE D2 

3336666666 

3333333333 

7777777777 

3.567782079 

2336719012 

6665555666 

Number of Days on Study 

Tumors 

Tissues1 

Total 

Carcass ID Number 

Ovary 

Clitoral gland 

Genital System 

++M+++++++ 

1 

2 

60 

1 

1 

1 

59 

58 

++++++++++ 

Periovarian tissue, histiocytic sarcoma 

Tubulostromal adenoma 

Granulosa cell tumor benign 

Polyp stromal 

Histiocytic sarcoma 

uterus ++++++++++ 

X 

Histiocytic sarcoma 

Bone marrow 

Hematopoietic System 

Renal, histiocytic sarcoma 

Pancreatic, histiocytic sarcoma 

Iliac, histiocytic sarcoma 

Axillary, histiocytic sarcoma 

Lymph node 

Neoplasm NOS, metastatic, lung 

Histiocytic sarcoma 

Carcinoma, metastatic, lung 

Lymph node, bronchial 

Mast cell tumor benign 

Histiocytic sarcoma 

Carcinoma, metastatic 

Lymph node, mandibular 

Lymph node, mediastinal 

Histiocytic sarcoma 

Lymph node, mesenteric 

Histiocytic sarcoma 

Histiocytic sarcoma 

Carcinoma, metastatic, lung 

Thymus 

Spleen 

~~~ ~~ 

++++++++++ 

+++++M++++ 56 

1 

3 

1 

1 

13 

1 

60 

++++++M+++ 

++++++++++ 

X 

MM+M+I M+MM 

++++++++++ 

+++++M++++ 

1 

2 

1 

1 

1 

22 

2 

51 

1 

2 

1 

55 

56 

1 

60 

Carcinoma 

Mammary gland 

Integumentary System 

Histiocytic sarcoma 

Carcinoma, metastatic, lung 

Subcutaneous tissue, hemangioma 

Subcutaneous tissue, fibrosarcoma 

Skin 

2 

1 

++++++++++ 

++++++++++ 

1 

2 

60 

1 

60 

X 
Lesions in Female Mice 295 

1 mg/m3 (continued) 

Individual Animal Tumor Pathology of Female Mice in the 2-Year Inhalation Study of Nickel Sulfate Hexahydrate: 

TABLE D2 

1010373612216149959834800 

8167956126679005677911233 

2333344555555666666677777 

4214353781658561676948034 

8180973009011013926076989 

5656556665666666565655555 

Number of Days on Study 

Carcass ID Number 

~~~~ 

Bone 

Musculoskeletal System 

~~ 

Vertebra, osteosarcoma 

......................... X 

Brain 

Nervous System 

......................... 

Lung 

Larynx 

Respiratory System 

Carcinoma, metastatic, lung 

Neoplasm NOS 

Histiocytic sarcoma 

Hepatocellular carcinoma, metastatic, liver 

Fibrosarcoma, metastatic, skin 

Carcinoma 

Alveolar/bronchiolar carcinoma 

Trachea 

Nose 

......................... X 

......................... X 

X 

X 

X 

X 

X 

++++++++++A++++++++++++++ 

......................... 

None 

Special Senses System 

Kidney 

Urinary System 

Histiocytic sarcoma 

Carcinoma, metastatic, lung 

Urinary bladder 

......................... X 

X 

++++++++++A++++++++++++++ 

Multiple organs 

Systemic Lesions 

Lymphoma malignant 

Histiocytic sarcoma 

......................... X xx 

X X 
296 Nickel Sulfate Hexahydrate, NTP TR 454 

1 mg/m3 (continued) 

Individual Animal Tumor Pathology of Female Mice in the 2-Year Inhalation Study of Nickel Sulfate Hexahydrate: 

TABLE D2 

0001111112222222222223333 

3333333333333333333333333 

7777177777777777177717771 

Number of Days on Study 

Carcass ID Number 

8069934473401230681205751 

9228911336677778882236890 

5665566665555555556665556 

Vertebra, osteosarcoma 

Bone 

Musculoskeletal System 

......................... 

Lung 

Larynx 

Respiratory System 

Brain 

Nervous System 

......................... 

......................... 

++I +I +++++++I +++I ++++++++ 

Carcinoma, metastatic, lung 

Neoplasm NOS 

Histiocytic sarcoma 

Hepatocellular carcinoma, metastatic, liver 

Fibrosarcoma, metastatic, skin 

Carcinoma 

Alveolar/bronchiolar carcinoma 

Trachea 

Nose 

......................... 

......................... 

None 

Special Senses System 

Urinary System 

Kidney 

Histiocytic sarcoma 

Carcinoma, metastatic, lung 

Urinary bladder 

......................... 

......................... 

Multiple organs 

Systemic Lesions 

Lymphoma malignant 

Histiocytic sarcoma 

......................... 

xx X X 
Lesions in Female Mice 297 

1 mg/m3 (continued) 

Individual Animal Tumor Pathology of Female Mice in the 2-Year Inhalation Study of Nickel Sulfate Hexahydrate: 

TABLE D2 

3336666666 

3333333333 

7777777777 

Number of Days on Study 

Carcass ID Number 

3567782079 

2336779012 

6665555666 

Tumors 

Tissues/ 

Total 

Bone 

Musculoskeletal System 

Vertebra, osteosarcoma 

++++++++++ 

1 

60 

Brain 

Nervous System ~~ ~ 

++++++++++ 60 ~~ 

Lung 

Larynx 

Respiratory System ~~ ~ 

Carcinoma, metastatic, lung 

Neoplasm NOS 

Histiocytic sarcoma 

Hepatocellular carcinoma, metastatic, liver 

Fibrosarcoma, metastatic, skin 

Carcinoma 

Alveolar/bronchiolar carcinoma 

Trachea 

Nose 

~~~~~~ 

++++++++++ 

++++++++++ 

++++++++++ 

++++++++++ 

59 

60 

1 

1 

1 

1 

1 

1 

60 

1 

56 

None 

Special Senses System 

Kidney 

Urinary System 

Histiocytic sarcoma 

Carcinoma, metastatic, lung 

Urinary bladder 

++++++++++ 

+++++++M++ 58 

1 

1 

60 

Multiple organs 

Systemic Lesions 

Lymphoma malignant 

Histiocytic sarcoma 

++++++++++ 

X 

6 

4 

60 
298 Nickel Sulfate Hexahydrate, NTP TR 454 

0 mg/m’ 0.25 mg/m’ 0.5 mglm’ 1 mg/m3 

Fisher exact test 

Cochm-Armita e testd 

Logistic regression testd 

Life table tese 

First incidence (days) 

Terminal rate‘ 

Adjusted rateb 

Overall ratea 

Harderian Gland: Adenoma 

Fisher exact test 

Cochran-Armitage test 

Logistic regression test 

Life table test 

First incidence (days) 

Terminal rate 

Adjusted rate 

Overall rate 

Liver: Hepatocellular Adenoma 

Fisher exact test 

Cochran-Armitage test 

Logistic regression test 

Life table test 

First incidence (days) 

Terminal rate 

Adjusted rate 

Overall rate 

Liver: HepatoceUular Carcinoma 

Fisher exact test 

Cochran-Armitage test 

Logistic regression test 

Life table test 

First incidence (days) 

Terminal rate 

Adjusted rate 

Overall rate 

Liver: Hepatocellular Adenoma or Carcinoma 

Fisher exact test 

Cochran-Armitage test 

Logistic regression test 

Life table test 

First incidence (days) 

Terminal rate 

Adjusted rate 

Overall rate 

Lung: Alveolarhronchiolar Adenoma 

% 

0134 (0%) 

0.0% 

0161 (0%) 

e 

P=0.560N 

P=0.563N 

P=0.547N 

- 

P=0.160N 

P=0.161N 

P=O.llON 

547 

11/34 (32%) 

35.0% 

13/61 (21%) 

P=O.386 

P=O.353 

P=O.410 

530 

4/34 (12%) 

17.4% 

7/61 (1 1 %) 

P=0.333N 

P=0.344N 

P=0.273N 

530 

14/34 (41 %) 

45.9% 

18/61 (30%) 

P=0.074N 

P=0.067N 

P=0.059N 

730 (T) 

3/34 (9%) 

8.8% 

3/61 (5%) 

P=O.236 

P=O.262 

635 

1/39 (3 %) 

4.6% 

2/60 (3 X) 

P=O.244 

P=O.519 

P=0.529N 

635 

13/39 (33%) 

34.7% 

14/59 (24%) 

P=O.461 

P=O.O42 

P=O.123 

51 1 

4/39 (10%) 

27.7% 

14/59 (24%) 

P=O.O63 

P=O.O39 

P=O.125 

51 1 

17/39 (44%) 

55.5% 

28/59 (47%) 

P=O.O33 

P=0.638N 

P=0.602N 

711 

1/39 (3%) 

7.2% 

3/60 (5 %) 

P=O.652 

P=O.O68 

P=O.O97 

672 

2/45 (4%) 

8.3% 

4/60 (7 X) 

P=O.O57 

P=0.314N 

P=0.172N 

68 1 

10145 (22%) 

23.8% 

11/60 (18%) 

P=0.428N 

P=0.350N 

P=0.245N 

68 1 

4/45 (9%) 

10.8% 

5/60 (8%) 

P=0.393N 

P=0.245N 

P=O.lOlN 

68 1 

14/45 (31 X) 

32.5% 

15/60 (25%) 

P=0.362N 

P=0.373N 

P=0.373N 

730 (T) 

2/45 (4%) 

4.4% 

2/60 (3 %) 

P=0.508N 

0137 (0%) 

0.0% 

0160 (0%) 

- 

- 

- 

- 

P=0.26tN 

P=O. 193N 

669 

6/37 (16%) 

22.2% 

9/60 (15%) 

P=0.254N 

P=O.188 

P=O.251 

516 

5/37 (14%) 

23.6% 

11/60 (18%) 

P=O.211 

P=O.464 

P=O.567 

516 

11/37 (30%) 

41 .O% 

19/60 (32%) 

P=O.476 

0137 (0%) 

0.0% 

0/60 (0%) 

P=0.125N 

P=0.106N 

P=0.106N 

- 
Lesions in Female Mice 299 

(continued) 

Statistical Analysis of Primary Neoplasms in Female Mice in the 2-Year Inhalation Study of Nickel Sulfate Hexahydrate 

TABLE D3 

O mg/m3 0.25 mg/m3 0.5 mg/m3 1 mg/m3 

Fisher exact test 

Cochran-Armitage test 

Logistic regression test 

Life table test 

First incidence (days) 

Terminal rate 

Adjpsted rate 

Overall rate 

Lung: Alveolarhronchiolar Carcinoma 

Fisher exact test 

Cochran-Armitage test 

Logistic regression test 

Life table test 

First incidence (days) 

Terminal rate 

Adjusted rate 

Overall rate 

Lung: Alveolarhronchiolar Adenoma or Carcinoma 

Fisher exact test 

Cochran-Armitage test 

Logistic regression test 

Life table test 

First incidence (days) 

Terminal rate 

Adjusted rate 

Overall rate 

Pituitary Gland (Pars Distalis): Adenoma 

Fisher exact test 

Cochran-Armitage test 

Logistic regression test 

Life table test 

First incidence (days) 

Terminal rate 

Adjusted rate 

Overall rate 

Skin (Subcutaneous Tissue): Fibrosarcoma 

Fisher exact test 

Cochran-Armitage test 

Logistic regression test 

Life table test 

First incidence (days) 

Terminal rate 

Adjusted rate 

Overall rate 

Uterus: Stromal Polyp 

10.7% 

4/61 (7%) 

P=0.410N 

P=0.415N 

P=0.378N 

627 

3/34 (9%) 

P=O.lllN 

P=O.lllN 

P=0.089N 

627 

6/34 (18 %) 

19.3% 

7/61 (11%) 

P=0.096N 

P=0.086N 

P=0.072N 

696 

4/33 (12%) 

20.6% 

8/59 (14%) 

P=0.237N 

P=0.276N 

P=0.239N 

384 

0134 (0%) 

9.5% 

5/61 (8%) 

P=O.246W 

P=0.246N 

P=0.229N 

730 (T) 

2/34 (6%) 

5.9% 

2/61 (3%) 

P=0.493N 

P=0.444N 

649 

2/39 (5 X) 

7.1% 

3/60 (5%) 

P=0.509N 

P=0.481N 

P=0.415N 

649 

3/39 (8%) 

13.9% 

6/60 (10%) 

P=0.513N 

P=O.491 

P=O.589 

559 

7/38 (18%) 

21.8% 

9/56 (16%) 

P=O.453 

0139 (0%) 

0.0% 

0160 (0%) 

P=0.037N 

P=0.037N 

- 

P=0.030N 

P=O.502 

P=O.545 

614 

1/39 (3 X) 

P=O.492 

P=O.149 

P=O.238 

656 

7/45 (16%) 

18.9% 

9/60 (15%) 

P=O.114 

P=O.371 

P=O.512 

656 

8/45 (18%) 

21.1% 

10/60 (17%) 

P=O.288 

P=0.190N 

P=0.144N 

730 (T) 

5/45 (1 1 %) 

11.1% 

5/59 (8 %) 

P=0.279N 

P=O.lSlN 

P=0.095N 

510 

0145 (0%) 

1.7% 

1/60 (2%) 

P=0.107N 

0145 (0%) 

0.0% 

0160 (0%) 

P=0.252N 

P=0.179N 

P=0.179N 

- 

P=0.346N 

P=0.332N 

562 

0137 (0%) 

4.3% 

2/60 (3%) 

P=0.348N 

P=0.088N 

P=0.077N 

562 

0137 (0%) 

4.3% 

2/60 (3 %) 

P=O.O86N 

P=0.186N 

P=0.172N 

60 1 

1/37 (3%) 

9.4% 

4/57 (7%) 

P=0.198N 

P=0.239N 

P=0.233N 

393 

1/37 (3%) 

4.4% 

2/60 (3 %) 

P=0.226N 

P=0.470N 

P=0.470N 

730 (T) 

1/37 (3%) 

2.7% 

1/60 (2%) 

P=0.506N 
300 Nickel Sulfate Hexahydrate, NTP TR 454 

O mg/m3 0.25 mg/m3 0.5 mg/m3 1 mg/m3 

Fisher exact test 

Cochran-Arrnitage test 

Logistic regression test 

Life table test 

First incidence (days) 

Terminal rate 

Adjusted rate 

Overall rate 

All Organs: Malignant Lymphoma 

Fisher exact test 

Cochran-Armitage test 

Logistic regression test 

Life table test 

First incidence (days) 

Terminal rate 

Adjusted rate 

Overall rate 

All Organs: Histiocytic Sarcoma 

Fisher exact test 

Cochran-Amitage test 

Logistic regression test 

Life table test 

First incidence (days) 

Terminal rate 

Adjusted rate 

Overall rate 

All Organs: Benign Neoplasms 

Fisher exact test 

Cochran-Armitage test 

Logistic regression test 

Life table test 

First incidence (days) 

Terminal rate 

Adjusted rate 

Overall rate 

All Organs: Malignant Neoplasms 

P=0.297N 

P=0.305N 

P=0.258N 

626 

3/34 (9%) 

17.6% 

7/61 (11%) 

P=O.212 

P=O.212 

P=O.217 

670 

0/34 (0%) 

2.3% 

1/61 (2%) 

P=O.OOSN 

P=0.004N 

P=0.003N 

547 

17/34 (50%) 

60.9% 

27/61 (44%) 

P=O.535 

P=O.534 

P=0.467N 

384 

12/34 (35%) 

53.2% 

26/61 (43 %) 

P=O.174 

P=O.238 

687 

9/39 (23 %) 

28.4% 

12/60 (20%) 

P=O.149 

P=O.172 

P=O.213 

398 

2/39 (5 X) 

9.1 % 

4/60 (7%) 

P=O.177 

P=O.145 

P=O.333 

559 

25/39 (64%) 

70.5% 

34/60 (57%) 

P=0.118 

P=O.486 

P=0.478N 

398 

15/39 (38%) 

52.4% 

27/60 (45 %) 

P=O.468 

P=O.435 

PzO.574 

567 

6/45 (13%) 

18.3% 

9/60 (15%) 

P=O.381 

P=O.474 

P~O.551 

577 

1/45 (2 %) 

4.0% 

2/60 (3 %) 

P=O.494 

P=0.155N 

P=0.056N 

672 

20/45 (44%) 

47.8% 

23/60 (38%) 

P=0.317N 

€'=OS67 

P=0.252N 

510 

17/45 (38%) 

47.7% 

26/60 (43 %) 

P=O.542 

P=0.523N 

P=0.467N 

596 

4/37 (11%) 

15.0% 

6/60 (10%) 

P=0.513N 

P=O.O89 

P=O.181 

57 1 

1/37 (3 %) 

8.8% 

4/60 (7 %) 

P=O.177 

P=0.032N 

P=0.025N 

60 1 

11/37 (30%) 

37.7% 

16/60 (27%) 

P=0.033N 

P=O.546 

P=0.516N 

393 

12/37 (32%) 

50.1 % 

26/60 (43 %) 

P=O.542 
Lesions in Female Mice 301 

(continued) 

Statistical Analysis of Primary Neoplasms in Female Mice in the 2-Year Inhalation Study of Nickel Sulfate Hexahydrate 

TABLE D3 

O mg/m3 0.25 mg/m3 0.5 mg/m3 1 mg/m3 

Fisher exact test 

Cochran-Armitage test 

Logistic regression test 

Life table test 

First incidence (days) 

Terminal rate 

Adjusted rate 

Overall rate 

All Organs: Benign or Malignant Neoplasms 

P=0.131N 

P=0.128N P=O.264 P=0.480N P=0.263N 

P=0.129N P=0.545N P=O. 115N P=0.223N 

384 398 510 393 

24/34 (71 %) 28/39 (72 %) 30/45 (67%) 19/37 (51 %) 

80.1 % 80.4% 73.1% 66.6% 

41/61 (67%) 45/60 (75 %) 41/60 (68%) 36/60 (60%) 

P=O.229 P=O.525 P=0.263N 

a Number of neoplasm-bearing animals/number of animals examined. Denominator is number of animals examined microscopically for liver, lung, pituitary 

(T)Terminal sacrifice 

compare directly the overall incidence rates. For all tests, a negative trend or a lower incidence in an exposure group is indicated by N. 

(directly or indirectly) the cause of death. The logistic regression test regards these lesions as nonfatal. The Cochran-Armitage and Fisher exact tests 

painvise comparisons between the controls and that exposed group. The life table test regards neoplasms in animals dying prior to terminal kill as being 

Beneath the control incidence are the P values associated with the trend test. Beneath the exposed group incidence are the P values corresponding to 

Observed incidence at terminal kill 

Kaplan-Meier estimated neoplasm incidence at the end of the study after adjustment for intercurrent mortality 

gland, and uterus; for other tissues, denominator is number of animals necropsied. 

e Not applicable; no neoplasms in animal group 
302 Nickel Sulfate Hexahydrate, NTP TR 454 

Historical Incidence of Alveolar/bronchiolar Neoplasms in Untreated Female B6C3F, Micea 

TABLE D4 

Study Carcinoma 

Incidence in Controls 

Adenoma Adenoma or Carcinoma 

Historical Incidence at Lovelace Inhalation Toxicology Research Institute 

Talc 

Nickel Sulfate Hexahydrate 

Nickel Subsulfide 

Nickel Oxide 

3/46 

3/61 

3/58 

2/64 

Overall Historical Incidence in Inhalation Studies 

Range 

Standard deviation 

Total 

0%-14% 

3/1 % 

6/94 (6.5%) 

Overall Historical Incidence in Feed Studies 

Range 

Standard deviation 

Total 

0%-24% 

5.0% 

78/1,319 (5.9%) 

2/46 

4/6 1 

7/58 

4/64 

0%-12% 

3.2% 

38/94 (4.0%) 

0%-8% 

2.3% 

26/1,319 (2.0%) 

5/46 

7/6 1 

9/58 

6/64 

0%-16% 

3.7% 

97/94 (10.3%) 

2%-26% 

5.3% 

102/1.319 (7.7%) 

a Data as of 17 June 1994 
Lesions in Female Mice 303 

of Nickel Sulfate Hexahydratea 

Summary of the Incidence of Nonneoplastic Lesions in Female Mice in the 2-Year Inhalation Study 

TABLE D5 

0 mg/m3 0.25 mglm’ 0.5 mg/m3 1 mg/m3 

Early deaths 

15-Month interim evaluation 

%Month interim evnlwtion 

Animals initially in study 

Disposition Summary 

Terminal sacrifice 

Died last week of study 

Natural deaths 

Moribund 

Survivors 

Animals examined microscopically 

5 

5 

71 

7 

20 

33 

1 

71 

5 

5 

70 

10 

11 

38 

1 

70 

5 

5 

70 

4 

11 

45 

70 

5 

5 

70 

6 

17 

37 

70 

Stomach, forestomach 

Alimentary System 

7-Month Interim Evaluation 

Diverticulum 

(1) 

1 (100%) 

Uterus 

Genital System 

Endometrium, hyperplasia 

Hyperplasia, lymphoid 

Lymph node, bronchial 

Hematopoietic System 

Hyperplasia, plasma cell 

Hyperplasia, lymphoid 

Lymph node, mandibular 

Lung 

Respiratory System 

(5) (5) (5) (5) 

Interstitium, infiltration cellular 

Inflammation, chronic active 

Hyperplasia, macrophage 

Olfactory epithelium, respiratory epithelium, 

Inflammation, acute 

1 (20%) 

1 (20%) 

2 (40%) 

5 (100%) 

4 (80%) 

Nose (5) (5) (5) (5) 

1 (20%) 

3 (60%) 4 (80%) 

1 (20%) 

1 (20%) 

degeneration 

Urinary System 

Special Senses System 

Nervous System 

Musculoskeletal System 

Integumentary System 

General Body System 

Endocrine System 

Cardiovascular System 

Systems Examined With No Lesions Observed 

a Number of animals examined microscopically at the site and the number of animals with lesion 
304 Nickel Sulfate Hexahydrate, NTP TR 454 

of Nickel Sulfate Hexahydrate (continued) 

Summary of the Incidence of Nonneoplastic Lesions in Female Mice in the 2-Year Inhalation Study 

TABLE D5 

0 mg/m3 0.25 mg/m3 0.5 mg/m3 1 mg/m3 

Parathyroid gland 

Endocrine System 

15-Month Interim Evaluation 

Thyroid gland 

Pituitary gland 

(5) 

(5) 

(4) 

(5) 

(5) 

(3) 

(5) 

(5) 

(5) 

(5) 

(4) 

(3) 

cyst 1 (33%) 

cyst 

Pars distalis, hyperplasia, focal 1 (20%) 2 (50%) 

1 (20%) 

Follicular cell, hyperplasia, focal 1 (20%) 

Clitoral gland 

Genital System 

Inflammation 

Ectasia 

Ovary 

Endometrium, hyperplasia 

Periovarian tissue, cyst 

cyst 

Uterus 

Hyperplasia, lymphoid 

Lymph node, bronchial 

Hematopoietic System 

Thymus 

Hyperplasia, lymphoid 

Spleen 

Hyperplasia, lymphoid 

Lymph node, mandibular 

Hyperplasia, macrophage 

cyst 

Skin 

Integumentary System 

(5) 

Subcutaneous tissue, inflammation 

Lung 

Larynx 

Respiratory System 

Hyperplasia, macrophage 

Inflammation 

Interstitium, infiltration cellular 

Alveolus, proteinosis 

Alveolar epithelial hyperplasia, focal 

Bronchialization 

Inflammation, chronic active 

1 (20%) 

(5) 

(4) 

(5) 

(2) 

(5) 

(4) 

1 (20%) 

1 (25%) 

1 (20%) 

2 (40%) 

5 (100%) 

5 (100%) 

5 (100%) 

5 (100%) 

5 (100%) 

1 (20%) 
Lesions in Female Mice 305 

of Nickel Sulfate Hexahydrate (continued) 

Summary of the Incidence of Nonneoplastic Lesions in Female Mice in the 2-Year Inhalation Study 

TABLE D5 

O mg/m3 0.25 mg/m3 0.5 mg/m3 1 mg/m3 

Nose 

Respiratory System (continued) 

IS-Month Interim Evaluation (continued) 

(5) (5) (5) (5) 

Vomeronasal organ, infiltration cellular, 

Respiratory epithelium, degeneration 

Olfactory epithelium, degeneration 

Olfactory epithelium, atrophy 

Inflammation, acute 

1 (20%) 

1 (20%) 

1 (20%) 

1 (20%) 

2 (40%) 

1 (20%) 

1 (20%) 

2 (40%) 

1 (20%) 

2 (40%) 

polymorphonuclear 

Urinary System 

Special Senses System 

Nervous System 

Musculoskeletal System 

General Body System 

Cardiovascular System 

Alimentary System 

Systems Examined With No Lesions Observed 

Gallbladder 

Alimentary System 

2-Year Study 

Concretion 

Autolysis 

Autolysis 

Autolysis 

Dilatation 

Autolysis 

Intussusception 

Inflammation 

Autolysis 

Autolysis 

Peyer’s patch, hyperplasia, lymphoid 

Bile duct, degeneration 

Necrosis, diffuse 

Necrosis 

Inflammation 

Infarct 

Hepatodiaphragmatic nodule 

Hemorrhage 

Hematopoietic cell proliferation 

Fatty change 

Eosinophilic focus 

Congestion 

Basophilic focus 

Intestine small, duodenum 

Intestine large, cecum 

Intestine large, rectum 

Intestine small, jejunum 

Liver 

Intestine small, ileum 

1 (2%) 

(61) 

2 (3%) 

1 (2%) 

1 (2%) 

1 (2%) 

4 (7%) 

2 (3%) 

1 (2%) 

2 (3%) 

(55) 

1 (2%) 

1 (2%) 

1 (2%) 

4 (7%) 

1 (2%) 

1 (2%) 

(55) 

1 (2%) 

(58) 

2 (3%) 

1 (2%) 

1 (2%) 

2 (3%) 

1 (2%) 

1 (2%) 

1 (2%) 

1 (2%) 

6 (10%) 

2 (3%) 
306 Nickel Sulfate Hexahydrate, NTP TR 454 

TABLE D5 

of Nickel Sulfate Hexahydrate (continued) 

Summary of the Incidence of Nonneoplastic Lesions in Female Mice in the 2-Year Inhalation Study 

0 mg/m3 0.25 mg/m3 0.5 mg/m3 1 mg/m3 

Alimentary System (continued) 

Necrosis 

Inflammation, chronic 

Inflammation 

Infiitration cellular, lymphocyte 

Mesentery 

Duct, ectasia 

Duct, cyst, multiple 

Acinus, hyperplasia, focal 

Inflammation 

Infiltration cellular, lymphocyte 

Amyloid deposition 

Angiectasis 

Salivary glands 

Inflammation 

Hyperplasia, squamous 

Stomach, forestomach 

Peridontal tissue, inflammation 

Hyperplasia 

Pancreas 

Tooth 

Stomach, glandular 

(7) 

1 (14%) 

(4) 

1 (25%) 

1 (25%) 

(58) 

1 (2%) 

1 (2%) 

1 (2%) 

1 (2%) 

1 (2%) 

1 (2%) 

1 (2%) 

(60) 

1 (2%) 

(60) 

(2) 

2 (100%) 

(1) 

1 (100%) 

Heart 

Cardiovascular System 

(61) (59) (60) (60) 

Inflammation 

Infdtration cellular, lymphocyte 

Cardiomyopathy 1 (2%) 

1 (2%) 

1 (2%) 

2 (3%) 1 (2%) 

Endocrine System 

Extra adrenal tissue, inflammation 

Capsule, hyperplasia 

Hypertrophy 

Hyperplasia 

cyst 

Adrenal cortex 

Mineralization 

Hyperplasia 

Adrenal medulla 

Bilateral, hyperplasia 

Hyperplasia 

cyst 

Parathyroid gland 

Pars distalis, hyperplasia 

Pars distalis, angiectasis 

cyst 

Congestion 

Angiectasis 

Pituitary gland 

Follicular cell, hyperplasia, cystic 

Inflammation 

Thyroid gland 

(60) 

1 (2%) 

1 (2%) 

(57) 

1 (2%) 

(60) 

1 (2%) 

(40) (50) 

1 (2%) 

(49) 

1 (2%) 

1 (2%) 

1 (3%) 

(59) (59) (57) 

1 (2%) 

1 (2%) 

15 (25%) 

8 (14%) 

1 (2%) 

(60) 

12 (20%) 

3 (5%) 

(60) 

22 (37%) 

2 (4%) 

8 (14%) 

(59) 

20 (34%) 

2 (3%) 

11 (19%) 

1 (2%) 

(60) 

27 (45%) 27 (45%) 
Lesions in Female Mice 307 

of Nickel Sulfate Hexahydrate (continued) 

Summary of the Incidence of Nonneoplastic Lesions in Female Mice in the 2-Year Inhalation Study 

TABLE D5 

Tissue NOS 

General Body System 

%Year Study (continued) 

(5) (8) (4) (3) 

Mediastinum, infiltration cellular, 

Abdominal, inflammation 

Abdominal, cyst 

Thrombosis 

Mediastinum, inflammation 

1 (20%) 

1 (25%) 

1 (13%) 

1 (13%) 

1 (13%) 1 (33%) 

lymphocyte 

1 (20%) 

~~~ 

Genital System 

Pigmentation 

Inflammation 

Hyperplasia, squamous 

Ectasia 

Atrophy 

Clitoral gland 

Bilateral, cyst 

Pigmentation, hemosiderin 

Inflammation 

Hemorrhage 

cyst 

Atrophy 

Angiectasis 

Endometrium, hyperplasia 

Thrombosis 

Prolapse 

Inflammation 

Infiltration cellular, lymphocyte 

Hemorrhage 

Dilatation 

Congestion 

Ovary 

Uterus 

4 (7%) 

4 (7%) 

1 (2%) 

4 (7%) 2 (3%) 

3 (5%) 

2 (3%) 

(59) 

1 (2%) 

(59) 

1 (2%) 

1 (2%) 

2 (3%) 

8 (14%) 

1 (2%) 

1 (2%) 

(60) 

6 (10%) 

1 (2%) 

8 (14%) 

1 (2%) 

17 (28%) 

1 (2%) 

1 (2%) 

(60) 

1 (2%) 

25 (42%) 

1 (2%) 

1 (2%) 

1 (2%) 

1 (2%) 

1 (2%) 

30 (49%) 39 (65%) 41 (68%) 

Hematopoietic System 

Myeloid cell, hyperplasia 

Erythroid cell, hyperplasia 

Myelofibrosis 

Hyperplasia, plasma cell 

Hyperplasia, megakaryocyte 

Hyperplasia, histiocytic 

Bone marrow 

Pancreatic, inflammation 

Pancreatic, hyperplasia, lymphoid 

Pancreatic, hematopoietic cell proliferation 

Inguinal, pigmentation 

Inguinal, hyperplasia, lymphoid 

Inguinal, hyperplasia, histiocytic 

Iliac, hyperplasia, plasma cell 

Iliac, hyperplasia, lymphoid 

Lymph node 

(61) 

6 (10%) 

1 (2%) 

39 (64%) 

1 (2%) 

1 (2%) 

1 (2%) 

1 (9%) 

1 (9%) 

(11) 

(60) 

1 (2%) 

(60) 

1 (2%) 

3 (27%) 

4 (7%) 

43 (73%) 

1 (8%) 

2 (3%) 

52 (87%) 

(11) (13) 

1 (8%) 

3 (5%) 

41 (68%) 

1 (8%) 

1 (8%) 

1 (8%) 

1 (8%) 

2 (15%) 

1 (8%) 

(13) 

2 (18%) 2 (15%) 

1 (9%) 1 (8%) 

1 (9%) 
308 Nickel Sulfate Hexahydrate, NTP TR 454 

of Nickel Sulfate Hexahydrate (continued) 

Summary of the Incidence of Nonneoplastic Lesions in Female Mice in the 2-Year Inhalation Study 

TABLE D5 

0 mg/m3 0.25 mg/m3 0.5 mg/m3 1 mg/m3 

Lymph node (continued) 

Hematopoietic System (continued) 

2-YeUr shcdy (continued) 

Renal, hyperplasia, plasma cell 

Renal, hyperplasia, lymphoid 

Renal, hyperplasia, histiocytic 

Renal, fibrosis 

Inflammation 

Hyperplasia,-plasma cell 

Hyperplasia, macrophage 

Hyperplasia, lymphoid 

Hyperplasia, histiocytic 

Hemorrhage 

Edema 

Congestion 

Amyloid deposition 

Lymph node, bronchial 

Congestion 

Lymph node, mandibular 

- cyst 

Inflammation 

Hyperplasia, plasma cell 

Hyperplasia, mast cell 

Hyperplasia, lymphoid 

' Hyperplasia, histiocytic 

Inflammation 

Hyperplasia, plasma cell 

Hyperplasia, lymphoid 

Hyperplasia, histiocytic 

Hemorrhage 

Hematopoietic cell proliferation 

Edema 

Congestion 

Inflammation 

Hyperplasia, plasma cell 

Hyperplasia, lymphoid 

Hyperplasia, histiocytic 

Lymph node, mediastinal 

Necrosis 

Hyperplasia, plasma cell 

Hyperplasia, lymphoid 

Hematopoietic cell proliferation 

Congestion 

Angiectasis 

Hyperplasia, lymphoid 

Autolysis 

Atrophy 

Lymph node, mesenteric 

Spleen 

Thymus 

(11) 

1 (9%) 

1 (9%) 

(50) 

1 (2%) 

1 (2%) 

1 (2%) 

2 (4%) 

2 (4%) 

15 (30%) 

15 (27%) 

1 (2%) 

1 (2%) 

(56) 

5 (9%) 

(57) 

1 (2%) 

1 (2%) 

4 (7%) 

1 (2%) 

1 (2%) 

1 (2%) 

(30) 

1 (3%) 

3 (10%) 

(61) 

10 (16%) 

11 (18%) 

3 (5%) 

15 (26%) 

1 (2%) 

(58) 

2 (18%) 

(54) 

1 (2%) 

1 (2%) 

9 (17%) 

5 (9%) 

6 (11%) 

2 (4%) 

(52) 

3 (6%) 

1 (2%) 

1 (2%) 

1 (4%) 

1 (4%) 

(58) 

4 (7%) 

9 (16%) 

1 (2%) 

(54) 

11 (20%) 

(13) 

2 (15%) 

1 (8%) 

1 (8%) 

(56) 

37 (66%) 

26 (46%) 

1 (2%) 

1 (2%) 

(55) 

5 (9%) 

1 (2%) 

1 (2%) 

1 (2%) 

4 (7%) 

(51) 

2 (4%) 

2 (4%) 

1 (2%) 

(22) 

3 (14%) 

(60) 

1 (2%) 

10 (17%) 

9 (15%) 

(56) 

1 (2%) 

1 (2%) 

12 (21%) 
Lesions in Female Mice 309 

of Nickel Sulfate Hexahydrate (continued) 

Summary of the Incidence of Nonneoplastic Lesions in Female Mice in the 2-Year Inhalation Study 

TABLE D5 

0 mg/m3 0.25 mg/m3 0.5 mg/m3 1 mg/m3 

study (continued) 

Integumentary System 

Hyperplasia 

Ectasia 

Mammary gland 

Tail, inflammation 

Subcutaneous tissue, edema 

Pinna, inflammation 

Neck, inflammation 

Hindlimb, hemorrhage 

Dermis, inflammation, granulomatous 

Dermis, fibrosis 

Ulcer 

Inflammation 

Skin 

(61) 

1 (2%) 

1 (2%) 

1 (2%) 

1 (2%) 

1 (2%) 

1 (2%) 

1 (2%) 

1 (2%) 

1 (2%) 

Bone 

Musculoskeletal System 

(61) (60) (60) (60) 

Tibia, fracture 

Periosteum, femur, inflammation 

Fibula, fracture 

Femur, hyperostosis 

Inflammation 

Skeletal muscle 

1 (25%) 

1 (2%) 

1 (2%) 

1 (2%) 1 (2%) 

1 (2%) 

(4) (3) (3) 

1 (33%) 

Nervous System 

Pons, degeneration 

Meninges, inflammation 

Cerebmm, degeneration 

Compression 

Brain 

Larynx 

Respiratory System 

Inflammation 

Hyperplasia 

Degeneration 

Alveolus, proteinosis 

Alveolar epithelium, metaplasia, squamous 

Alveolar epithelial hyperplasia, focal 

Bronchialization 

Mineralization 

Inflammation, chronic active 

Inflammation 

Hyperplasia, macrophage 

Hemorrhage 

Emphysema 

Congestion 

Lung 

4 (7%) 

1 (2%) 

1 (2%) 

1 (2%) 

7 (11%) 

1 (2%) 

(61) (60) 

1 (2%) 

1 (2%) 

1 (2%) 

7 (12%) 

1 (2%) 

1 (2%) 

24 (40%) 

9 (15%) 

2 (3%) 

3 (5%) 

1 (2%) 

1 (2%) 

(60) 

53 (88%) 

14 (23%) 

32 (53%) 

1 (2%) 

11 (18%) 

59 (98%) 

40 (67%) 

45 (75%) 

45 (75%) 

1 (2%) 
310 Nickel Sulfate Hexahydrate, NTP TR 454 

of Nickel Sulfate Hexahydrate (continued) 

Summary of the Incidence of Nonneoplastic Lesions in Female Mice in the 2-Year Inhalation Study 

TABLE D5 

0 mg/m3 0.25 mg/m3 0.5 mg/m3 1 mg/m3 

Lung (continued) 

Respiratory System (continued) 

2-YeUt' shldy (continued) 

Pleura, inflammation 

Interstitium, infiltration cellular 

Bronchiole, degeneration 

Squamous epithelium, inflammation 

Squamous epithelium, hyperplasia 

Respiratory epithelium, metaplasia, squamous 

Respiratory epithelium, inflammation 

Respiratory epithelium, degeneration 

Olfactory epithelium, inflammation 

Olfactory epithelium, degeneration 

Olfactory epithelium, atrophy 

Hemorrhage 

Degeneration 

Nose 

Trachea 

4 (7%) 16 (27%) 

7 (12%) 

14 (24%) 

1 (2%) 

8 (14%) 

2 (3%) 

1 (2%) 

1 (2%) 

1 (2%) 

1 (2%) 

2 (3%) 

11 (18%) 

7 (12%) 

2 (3%) 

8 (13%) 

17 (28%) 

1 (2%) 

(59) 

1 (2%) 

5 (8%) 

11 (18%) 

3 (5%) 

11 (18%) 

4 (7%) 

1 (2%) 

(60) 

Ear 

Special Senses System 

Extraorbital,' hyperplasia, plasma cell 

Lacrimal gland 

External ear, inflammation 

Hemorrhage 

Kidney 

Urinary System 

Renal tubule, necrosis, acute 

Perirenal tissue, inflammation 

Pelvis, dilatation 

Medulla, cyst 

Glomerulus, inflammation 

Nephropathy 

Mineralization 

Metaplasia, osseous 

Inflammation 

Fibrosis 

Transitional epithelium, hyperplasia 

Inflammation 

Infiltration cellular, lymphocyte 

Hemorrhage 

Calculus, microscopic observation only 

Autolysis 

Angiectasis 

Urinary bladder 

1 (2%) 

3 (5%) 

1 (2%) 

1 (2%) 

1 (2%) 

2 (3%) 

1 (2%) 

1 (2%) 

2 (3%) .. 

1 (2%) 

(60) 

1 (2%) 

1 (2%) 

1 (2%) 

1 (2%) 

1 (2%) 

1 (2%) 

1 (2%) 1 (2%) 
311 

GENETIC TOXICOLOGY 

APPENDIX E 

............................... 

TABLE El Induction of Trifluorothymidine Resistance in L5178Y Mouse Lymphoma Cells 

Mourn LYMPHOMA MUTAGENICITYEST PROTOCOL 312 

RESULTS ......................................................... 312 

by Nickel Sulfate Hexahydrate ..................................... 313 
312 Nickel Sulfate Hexahydrate, NTP TR 454 

GENETIC TOXICOLOGY 

were replicated. 

was added. All treatment levels within an experiment, including concurrent positive and solvent controls, 

and to normal medium for 3 to 5 days. For cloning, horse serum content was increased and Noble agar 

medium containing THMG (thymidine, hypoxanthine, methotrexate, glycine) for 1 day, to THG for 1 day, 

of spontaneously occurring trifluorothymidine (TFT)-resistant cells, subcultures were exposed once to 

supplemented Fischer's medium; normal cycling time was approximately 10 hours. To reduce the number 

toxicity. L5178Y mouse lymphoma TK+'- cells were maintained at 37" C as suspension cultures in 

was supplied as a coded aliquot by Radian Corporation (Austin, TX). The high dose was determined by 

The experimental protocol is presented in detail by McGregor et al. (1988). Nickel sulfate hexahydrate 

MOUSE LYMPHOMA MUTAGENICITY TEST PROTOCOL 

performed with S9. 

performed without S9; because a clearly positive response was obtained, the experiment was not 

efficiency. Plates were incubated at 37 O C in 5 % CO, for 10 to 12 days. This assay is initially 

selection of TFT-resistant cells (TK-'-), and in nonselective medium and soft agar to determine cloning 

expression period, cells were plated in medium and soft agar supplemented with trifluorothymidine for 

phenotype. Cell density was monitored so that log phase growth was maintained. After the 48-hour 

cells were resuspended in fresh medium and incubated for an additional 2 days to express the mutant 

continued for 4 hours at which time the medium plus nickel sulfate hexahydrate was removed, and the 

Treated cultures contained 6 X lo6 cells in 10 mL of medium. Incubation with nickel sulfate hexahydrate 

conclusion, and the absence of both a trend and peak response resulted in a "negative" call. 

be considered capable of inducing TFT-resistance; a single significant response led to a "questionable" 

trend and peak responses. Both iesponses had to be significant (P10.05) for nickel sulfate hexahydrate to 

and data evaluation are presented in Caspary et al. (1988). All data were evaluated statistically for both 

Minimum criteria for accepting an experiment as valid and a detailed description of the statistical analysis 

RESULTS 

mutation assay in L5178Y cells without S9 activation (Table El); the test was not performed with S9. 

Nickel sulfate hexahydrate (effective dose range, 500-800 pg/mL) was positive in the mouse lymphoma 
Genetic Toxicity 313 

by Nickel Sulfate Hexahydratea 

Induction of Trifluorothymidine Resistance in L5178Y Mouse Lymphoma Cells 

TABLE El 

OlglmLI (%I ("/.I Fraction' 

Compound Concentration Efficiency Total Growth Count Fractionb Mutant 

Cloning Relative Mutant Mutant Average 

Trial 1 

-s9 

Medium 

51 

59 

70 

107 

76 

117 

117 

112 

94 

76 

63 

45 

61 

Methyl methanesulfonate 

15 30 

45 

47 

50 

266 

312 

297 

234 

265* 

Nickel sulfate hexahydrate 300 

400d 

89 148 120 45 

81 

75 

118 

132 

120 

117 

49 

52 

51 

61 

83 

72 

500 

72 

71 

90 

105 

131 

178 

600 

76 

65 

33 

19 

180 

235 

79 

I20 

99* 

700 

45 

47 

6 

8 

312 

274 

233 

194 

241* 

800 

lethal 

lethal 
314 Nickel Sulfate Hexahydrate, NTP TR 454 

by Nickel Sulfate Hexahydrate (continued) 

Induction of Trifluorothymidine Resistance in L5178Y Mouse Lymphoma Cells 

TABLE El 

WmL) (%) (%I Fraction 

Compound Concentration Efficiency Total Growth Count Fraction Mutant 

Cloning Relative Mutant Mutant Average 

Medium 

Trial 2 

-s9 (continued) 

87 

1 1 1 

94 

110 

98 

103 

98 

101 

145 

129 

154 

168 

56 

39 

55 

51 

50 

Methyl methanesulfonate 

15 61 

55 

32 

30 

227 

317 

125 

193 

159* 

Nickel sulfate hexahydrate 400d 

71 

95 

37 

40 

165 

190 

78 

67 

72 

500 

39 

25 

86 

61 

173 

205 

67 

112 

90* 

600 

47 

65 

12 

16 

262 

279 

187 

143 

165* 

700 

73 

30 

8 

5 

362 

365 

166 

408 

287* 

800 

51 

43 

5 

5 

292 

293 

192 

226 

209* 

900 

lethal 

lethal 

* Significant positive response (P10.05) 

Acidic pH shift at 400 pglmL 

Mean standard of error from three replicate plates of approximately 113 (3 x IO6) cells each 

MF = mutant fraction. 

Mutant fraction (frequency) is a ratio of the mutant count to the cloning efficiency, divided by 3 (to amve at MF/l X lo6 cells treated); 

a Study performed at Inveresk Research International. The experimental protocol and these data are presented in McGregor el al. (1988). 
315 

ORGAN-WEIGHT-TO-BODY=WEIGHT RATIOS 

ORGAN WEIGHTS AND 

APPENDIX F 

TABLE M 

TABLE F2 

TABLE F1 

TABLE F4 

TABLE F7 

TABLE F6 

TABLE F5 

TABLE MI 

of Nickel Sulfate Hexahydrate 

at the 15-Month Interim Evaluation in the 2-Year Inhalation Study 

Organ Weights and Organ-Weight-to-Body-Weight Ratios for Mice 

of Nickel Sulfate Hexahydrate 

at the 7-Month Interim Evaluation in the 2-Year Inhalation Study 

Organ Weights and Organ-Weight-to-Body-Weight Ratios for Mice 

in the 13-Week Inhalation Study of Nickel Sulfate Hexahydrate 

Organ Weights and Organ-Weight-to-Body-Weight Ratios for Mice 

in the 16-Day Inhalation Study of Nickel Sulfate Hexahydrate 

Organ Weights and Organ-Weight-to-Body-Weight Ratios for Mice 

of Nickel Sulfate Hexahydrate 

at the 15-Month Interim Evaluation in the 2-Year Inhalation Study 

Organ Weights and Organ-Weight-to-Body-Weight Ratios for Rats 

of Nickel Sulfate Hexahydrate 

at the 7-Month Interim Evaluation in the 2-Year Inhalation Study 

Organ Weights and Organ-Weight-to-Body-Weight Ratios for Rats 

in the 13-Week Inhalation Study of Nickel Sulfate Hexahydrate 

Organ Weights and Organ-Weight-to-Body-Weight Ratios for Rats 

in the 16-Day Inhalation Study of Nickel Sulfate Hexahydrate 

Organ Weights and Organ-Weight-to-Body-Weight Ratios for Rats 

................ 

317 

316 

............... 

..................................... 319 

..................................... 

322 

321 

320 

................ 

............... 

..................................... 324 

..................................... 325 
316 Nickel Sulfate Hexahydrate, NTP TR 454 

of Nickel Sulfate Hexahydratea 

Own Weights and Organ-Weight-to-Body-Weight Ratios for Rats in the 1fj-Day Inhalation Study 

TABLE F1 

0 mg/m3 3.5 mg/m3 7 mg/m3 15 mg/m3 30 mg/m3 60 mg/m3 

Brain 

Necropsy body wt 

Male 

n 

Relative 

Absolute 

Relative 

Absolute 

Relative 

Absolute 

Relative 

Absolute 

Relative 

Absolute 

Relative 

Absolute 

Relative 

Absolute 

Heart 

R. Kidney 

Liver 

Lung 

R. Testis 

Thymus 

Brain 

Necropsy body wt 

Female 

Relative 

Absolute 

Relative 

Absolute 

Relative 

Absolute 

Relative 

Absolute 

Relative 

Absolute 

Relative 

Absolute 

Heart 

R. Kidney 

Liver 

Lung 

Thymus 

5 

225 f 5 

1.55 f 0.12 

0.348 f 0.025 

5.76 f 0.19 

1.294 f 0.018 

4.36 f 0.07 

0.980 f 0.020 

40.83 f 0.53 

9.200 f 0.302 

3.73 f 0.05 

0.840 f 0.023 

3.19 f 0.06 

0.718 f 0.019 

7.85 f 0.23 

1.764 f 0.025 

147 f 4 

11.42 f 0.28 

1.674 f 0.011 

5.19 f 0.39 

0.760 f 0.051 

35.50 f 0.94 

5.220 f 0.211 

3.97 f 0.14 

0.583 f 0.019 

3.64 f 0.16 

0.534 f 0.021 

1.83 f 0.08 

0.270 f 0.014 

5 

162 f 8** 

0.688 f 0.033** 

4.02 f 0.14* 

0.646 f 0.017 

10.54 f 0.46** 

1.690 f 0.022* 

4.26 f 0.04 

8.90 f 0.28** 

1.440 f 0.087** 

43.84 f 1.07 

7.080 f 0.340** 

6.82 f 0.46 

1.090 f 0.046 

1.03 * 0.13** 

0.170 f 0.027** 

120 f 7** 

0.542 f 0.024 

13.36 f 0.61 

1.590 f 0.025** 

4.54 f 0.19** 

0.196 f 0.022** 

10.66 f 0.43* 

1.280 f 0.086* 

38.14 f 0.68 

4.580 f 0.260 

4.35 f 0.14 

0.519 f 0.017 

1.62 f 0.12 

5 

136 f 2** 

0.632 f 0.009 

12.15 f 0.12** 

1.654 f 0.020** 

0.796 k 0.081** 

10.63 f 0.36** 

1.450 f 0.029** 

44.04 f 1.09 

6.OOO f 0.202** 

4.49 f 0.05* 

0.611 f 0.012** 

4.64 f 0.06** 

5.87 f 0.65 

0.69 f 0.12** 

0.093 f 0.016** 

105 f 2** 

15.36 f 0.31** 

1.606 f 0.010* 

0.524 f 0.014 

5.02 f 0.19** 

0.535 f 0.021 

5.12 f 0.26** 

37.28 f 1.54 

3.900 f 0.152** 

1.14 f 0.14** 

0.1 19 f 0.015** 

12.24 f 0.63** 

1.280 f 0.058* 

5 

127 f 2** 

0.618 f 0.019 

12.93 f 0.23** 

1.640 f 0.025** 

0.818 * 0.105** 

11.03 f 0.25** 

1.400 f 0.032* 

41.71 f 2.97 

5.280 f 0.341** 

4.84 f 0.07** 

0.613 f 0.007** 

4.87 f 0.13** 

6.43 f 0.77 

0.84 f 0.10** 

0.106 f 0.012** 

100 f 5** 

0.516 f 0.035 

16.19 f 0.76** 

1.606 f 0.011* 

5.15 f 0.22** 

0.527 f 0.021 

13.18 f 0.47** 

1.320 f 0.080* 

37.70 f 1.28 

3.760 f 0.150** 

5.28 f 0.08** 

0.98 f 0.18** 

0.101 f 0.022** 

5 

123 f 9** 

0.626 f 0.046 

13.73 f 0.93** 

1.654 f 0.009** 

0.462 f 0.029** 

11.57 f 0.83** 

1.400 f 0.071* 

37.71 f 2.38 

4.580 f 0.287** 

4.70 f 0.36** 

0.566 f 0.017** 

5.14 f 0.37** 

3.81 f 0.26 

0.52 f 0.12** 

0.064 f 0.015** 

93 f 3** 

0.478 f 0.032 

16.84 f 0.50** 

1.564 f 0.025** 

5.11 f 0.21** 

0.525 f 0.042 

5.64 f 0.42** 

0.54 f 0.12** 

0.051 f 0.012** 

14.99 * 2.90** 

1.400 f 0.279** 

44.49 f 2.15** 

4.160 f 0.301** 

5 

112 f 7** 

0.630 f 0.038 

14.98 f 0.93** 

1.652 f 0.027** 

0.618 f 0.128** 

14.12 f 1.35** 

1.620 f 0.269** 

41.09 f 1.70 

4.600 f 0.356** 

5.41 f 0.29** 

0.612 f 0.068** 

5.71 f 0.50** 

5.36 f 0.84 

0.43 f 0.17** 

0.053 f 0.023** 

90 f 6**b 

0.482 f 0.032 

18.19 f 1.45** 

1.594 f 0.015* 

5.42 f 0.28** 

0.548 f 0.034 

6.16 f 0.27** 

3.280 f 0.312** 

0.65 f 0.17** 

0.061 f 0.016** 

17.46 f 2.47** 

1.520 f 0.166** 

36.58 f 2.23 

a Organ weights and body weights are given in grams; organ-weight-to-body-weight ratios are given as mg organ weighug body weight 

** P10.01 

* Significantly different (PSO.05) from the control group by Williams’ or Dunnett’s test 

All animals in this exposure group died early 

(mean f standard error). 
Organ Weight Analyses 317 

of Nickel Sulfate Hexahydratea 

Organ Weights and Organ-Weight-to-Body-Weight Ratios for Rats in the 13-Week Inhalation Study 

TABLE F2 

0 mg/m3 0.12 mg/m3 0.25 mg/m3 0.5 mglm3 1 mg/m3 2 mg/m3 

Brain 

Necropsy body wt 

n 

Male 

Relative 

Absolute 

Relative 

Absolute 

Relative 

Absolute 

Relative 

Absolute 

Relative 

Absolute 

Relative 

Absolute 

Relative 

Absolute 

Heart 

R. Kidney 

Liver 

1 

Lung 

R. Testis 

Thymus 

10 

327 f 5 

0.82 f 0.03 

0.268 f 0.011 

4.30 f 0.14 

1.402 f 0.033 

4.13 f 0.14 

1.350 f 0.043 

35.09 f 0.63 

11.480 f 0.241 

3.38 f 0.06 

1.108 f 0.030 

2.95 f 0.09 

0.966 f 0.035 

5.78 f 0.07 

1.889 f 0.013 

10 10 10 10 9 

328 f 4 334 f 5 311 f 5 324 f 5 310 f 8 

1.888 f 0.017 1.907 f 0.019 1.860 f 0.021 1.916 f 0.010 1.870 f 0.024 

5.76 f 0.06 5.71 f 0.08 6.00 f 0.07 5.93 f 0.09 6.06 f 0.13* 

0.930 f 0.018 0.958 f 0.026 0.968 f 0.046 0.960 f 0.019 0.912 f 0.028 

2.83 f 0.05 2.87 f 0.09 3.11 f 0.13 2.97 f 0.06 2.96 f 0.10 

1.062 f 0.026 1.120 f 0.022 1.079 f 0.035 1.082 f 0.018 1.063 f 0.041 

3.24 f 0.07 3.35 f 0.04 3.48 f 0.10 3.35 f 0.04 3.44 f 0.14 

11.830 f 0.235 11.690 f 0.316 10.890 f 0.294 11.090 f 0.164 10.644 f 0.244* 

36.04 f 0.58 34.94 f 0.66 35.06 f 0.77 34.30 f 0.42 34.43 f 0.55 

1.376 f 0.012 1.375 f 0.052 1.376 f 0.031 1.443 f 0.042 1.352 f 0.035 

4.20 f 0.06 4.11 f 0.13 4.43 f 0.07 4.46 f 0.11 4.38 f 0.11 

0.248 f 0.009 0.261 rt 0.014 0.265 f 0.009 0.273 f 0.015 0.254 f 0.017 

0.76 f 0.03 0.78 f 0.04 0.86 f 0.03 0.84 f 0.04 0.83 f 0.06 
318 Nickel Sulfate Hexahydrate, NTP TR 454 

of Nickel Sulfate Hexahydrate (continued) 

Organ Weights and Organ-Weight-to-Body-Weight Ratios for Rats in the 13-Week Inhalation Study 

TABLE F2 

0 mg/m3 0.12 mg/m3 0.25 mg/m3 0.5 mg/m3 1 mg/m3 2 mg/m3 

Brain 

Necropsy body wt 

n 

Female 

Relative 

Absolute 

Relative 

Absolute 

Relative 

Absolute 

Relative 

Absolute 

Relative 

Absolute 

Relative 

Absolute 

Heart 

R. Kidney 

Liver 

Lung 

Thymus 

10 

198 f 5 

1.23 f 0.04 

0.244 f 0.010 

5.18 f 0.11 

1.022 f 0.021 

36.34 f 0.61 

7.180 f 0.149 

3.64 f 0.08b 

0.713 f 0.015b 

3.35 f 0.06 

0.661 f 0.013 

9.03 f 0.23 

1.778 f 0.016 

10 

195 f 5 

35.46 f 1.05 

6.960 f 0.357 

3.60 f 0.08 

0.704 f 0.026 

3.44 f 0.09 

0.673 f 0.026 

9.13 f 0.15 

1.777 f 0.021 

1.16 f 0.02 

0.227 f 0.007 

5.20 f 0.09 

1.017 f 0.033 

10 

193 f 4 

6.05 f 0.17** 

1.162 f 0.016** 

35.47 f 0.63 

6.850 f 0.231 

3.84 f 0.12b 

0.740 f 0.023b 

3.51 f 0.08 

0.675 f 0.015 

9.18 f 0.19 

1.763 f 0.014 

1.16 f 0.03 

0.223 f 0.007 

10 

189 f 3 

7.06 f 0.29** 

1.335 f 0.051** 

33.78 f 0.80 

6.400 f 0.193 

3.68 f 0.09 

0.697 f 0.019 

3.72 f 0.16 

0.703 f 0.030 

9.25 f 0.19 

1.748 f 0.015 

1.16 f 0.05 

0.219 f 0.011 

10 

193 f 3 

8.87 f 0.14** 

1.715 f 0.040** 

34.15 f 0.85 

6.600 f 0.183 

3.62 f 0.07 

0.698 f 0.013 

3.47 f 0.13 

0.669 f 0.019 

9.11 f 0.16 

1.758 * 0.025 

1.26 f 0.06 

0.245 f 0.013 

10 

184 f 4 

9.48 f 0.24 

1.738 f 0.024 

3.55 f 0.06 

0.653 f 0.016 

3.69 f 0.08 

0.678 f 0.015 

9.33 f 0.15**b 

1.722 f 0.044**b 

33.99 f 0.73 

6.270 f 0.227** 

1.34 f 0.08b 

0.249 f 0.017b 

a Organ weights and body weights are given in grams; organ-weight-to-body-weight ratios are given as mg organ weightlg body weight 

** PSO.01 

* Significantly different (PsO.05) from the control group by Williams’ or Dunnett’s test 

n=9 

(mean f standard error). 
Organ Weight Analyses 319 

in the 2-Year Inhalation Study of Nickel Sulfate Hexahydratea 

Organ Weights and Organ-Weight-to-Body-Weight Ratios for Rats at the 7-Month Interim Evaluation 

TABLE F3 

0 mg/m3 0.12 mg/m3 0.25 mg/mJ 0.5 mg/m3 

Brain 

Necropsy body wt 

Male 

n 

Relative 

Absolute 

Relative 

Absolute 

Relative 

Absolute 

Relative 

Absolute 

Relative 

Absolute 

Relative 

Absolute 

Relative 

Absolute 

R. Kidney 

Liver 

Lung 

Spleen 

R. Testis 

Thymus 

Brain 

Necropsy body wt 

Female 

Relative 

Absolute 

Relative 

Absolute 

Relative 

Absolute 

Relative 

Absolute 

Relative 

Absolute 

Relative 

Absolute 

R. Kidney 

Liver 

Lung 

Spleen 

Thymus 

5 

427 f 9 

0.72 f 0.07 

0.309 f 0.035 

3.51 f 0.40 

1.484 f 0.150 

1.86 f 0.03 

0.792 f 0.012 

3.93 f 0.15 

1.674 f 0.037 

39.88 f 1.12 

17.034 f 0.607 

3.52 f 0.15 

1.498 f 0.040 

4.79 f 0.12 

2.040 f 0.015 

245 f 6 

1.06 f 0.08 

0.260 f 0.019 

2.29 f 0.04 

0.560 f 0.020 

5.10 f 0.05 

1.250 f 0.041 

39.08 f 1.33 

9.582 f 0.493 

3.92 f 0.16 

0.960 f 0.050 

7.60 f 0.23 

1.856 f 0.045 

5 

390 f 7 

0.73 f 0.05 

0.285 f 0.016 

3.78 f 0.12 

1.470 f 0.032 

1.90 f 0.04 

0.740 f 0.028 

4.16 f 0.18 

1.622 f 0.080 

38.55 f 0.71 

15.032 f 0.449 

3.44 f 0.09 

1.344 f 0.055 

5.01 f 0.13 

1.950 f 0.043 

230 f 13 

0.91 f 0.05 

0.208 f 0.015 

2.24 f 0.07 

0.512 f 0.021 

5.35 f 0.26 

1.220 f 0.041 

38.54 f 1.06 

8.836 f 0.428 

3.99 f 0.14 

0.910 f 0.019 

7.87 f 0.39 

1.790 f 0.024 

5 

379 f 25 

0.54 f 0.04 

0.208 f 0.027* 

4.11 f 0.26 

1.534 f 0.038 

1.88 f 0.02 

0.712 f 0.043 

4.39 f 0.13* 

1.650 f 0.076 

35.94 f 2.34 

13.794 f 1.611 

3.59 f 0.09 

1.360 f 0.098 

5.67 f 0.64 

2.090 f 0.107 

236 f 8 

1.01 f 0.06 

0.237 f 0.016 

2.30 f 0.11 

0.540 f 0.023 

5.17 f 0.22 

1.218 f 0.071 

37.57 f 0.89 

8.860 f 0.404 

3.98 f 0.18 

0.938 f 0.061 

7.82 f 0.29 

1.834 f 0.042 

5 

395 f 7 

5.06 f 0.03 

2.OOO f 0.031 

3.46 f 0.08 

1.368 f 0.034 

37.32 f 1.33 

14.742 f 0.559 

1.886 f 0.056 

4.77 f 0.08** 

1.96 f 0.05 

0.772 f 0.019 

3.89 f 0.10 

1.534 f 0.019 

0.66 f 0.04 

0.260 f 0.021 

233 f 5 

7.75 f 0.18 

1.804 f 0.021 

3.84 f 0.14 

0.896 f 0.036 

39.05 f 1.83 

9.094 f 0.410 

6.24 f 0.20** 

1.454 f 0.047* 

2.33 f 0.05 

0.542 f 0.011 

0.87 f 0.05 

0.203 f 0.015 

a Organ weights and body weights are given in grams; organ-weight-to-body-weight ratios are given as mg organ weight/g body weight 

** P10.01 

* Significantly different (P10.05) from the control group by William’ or Dunnett’s test 

(mean f standard error). 
320 Nickel Sulfate Hexahydrate, NTP TR 454 

in the 2-Year Inhalation Study of Nickel Sulfate Hexahdyratea 

Organ Weights and Organ-Weight-to-Body-Weight Ratios for Rats at the 15-Month Interim Evaluation 

TABLE F4 

0 mg/m3 0.12 mg/m3 0.25 mg/m3 0.5 mg/m3 

n 5 5 5 5 

Brain 

Necropsy body wt 

Male 

Relative 

Absolute 

Relative 

Absolute 

Relative 

Absolute 

Relative 

Absolute 

Relative 

Absolute 

Relative 

Absolute 

R. Kidney 

Liver 

Lung 

Spleen 

Thymus 

485 f 7 486 f 14 472 f 10 469 f 8 

4.26 f 0.08 

2.064 f 0.014 

4.28 f 0.12 

2.074 f 0.020 

4.41 f 0.16 

2.074 f 0.048 

4.39 f 0.08 

2.056 f 0.007 

36.69 f 0.61 

17.788 f 0.504 

3.26 f 0.06 

1.582 f 0.041 

3.29 f 0.13 

1.594 f 0.056 

3.42 f 0.14 

1.608 f 0.046 

3.44 f 0.16 

1.610 f 0.055 

35.75 f 1.20 

17.384 f 0.827 

36.87 f 0.58 

17.370 f 0.278 

37.55 f 1.29 

17.614 f 0.697 

4.38 f 0.26 

2.118 f 0.100 

5.12 f 0.25 

2.482 f 0.102 

5.32 f 0.27 

2.504 f 0.107 

6.39 f 0.55** 

2.996 f 0.264** 

2.17 f 0.07 

1.050 f 0.033 

2.02 f 0.05 

0.980 f 0.034 

0.62 f 0.06 

0.294 f 0.034 

2.44 f 0.39 

1.142 f 0.174 

2.12 * 0.12 

0.994 f 0.061 

0.61 f 0.06 

0.287 f 0.025 

0.60 f 0.06 

0.289 f 0.032 

0.59 f 0.05 

0.291 f 0.032 

Necropsy body wt 

Female 

287 f 16 290 f 5 284 f 6 287 f 6 

Brain 

Relative 

Absolute 

Relative 

Absolute 

Relative 

Absolute 

Relative 

Absolute 

Relative 

Absolute 

Relative 

Absolute 

R. Kidney 

Liver 

Lung 

Spleen 

Thymus 

6.53 f 0.36 

1.848 f 0.028 

6.54 f 0.12 

1.896 f 0.017 

6.53 f 0.14 

1.852 f 0.014 

6.60 f 0.12 

1.894 f 0.050 

3.36 f 0.10 

0.952 f 0.022 

3.67 f 0.16 

1.054 f 0.064 

3.33 f 0.21 

0.944 f 0.038 

3.48 f 0.16 

1.012 f 0.056 

32.51 f 1.32 

9.282 f 0.482 

31.98 f 1.24 

9.288 f 0.445 

31.62 f 0.60 

8.998 f 0.366 

32.07 f 0.82 

9.196 f 0.275 

5.41 f 0.36 

1.576 f 0.128 

5.27 f 0.20 

1.492 f 0.042 

6.36 f 0.36** 

1.818 f 0.075** 

4.81 f 0.22 

1.372 f 0.068 

1.90 * 0.14 

0.544 f 0.038 

2.00 f 0.22 

0.562 f 0.038 

3.10 f 1.40 

0.920 f 0.433 

2.95 f 1.15 

0.830 f 0.314 

0.83 f 0.13 

0.244 f 0.046 

0.72 f 0.07 

0.208 f 0.018 

0.81 * 0.08 

0.231 f 0.025 

0.80 f 0.07 

0.229 f 0.017 

a Organ weights and body weights are given in grams; organ-weight-to-body-weight ratios are given as mg organ weighug body weight 

** Significantly different (P10.01) from the control group by Williams’ or Dunnett’s test 

(mean f standard error). 
Organ Weight Analyses 321 

of Nickel Sulfate Hexahydratea 

Organ Weights and Organ-Weight-to-Body-Weight Ratios for Mice in the 16-Day Inhalation Study 

TABLE F5 

0 mg/m3 3.5 mg/m3 7 mglm' 15 mg/m3 30 mg/m3 60 mg/m3 

Brain 

Necropsy body wt 

Male 

n 

Relative 

Absolute 

Relative 

Absolute 

Relative 

Absolute 

Relative 

Absolute 

Relative 

Absolute 

Relative 

Absolute 

Relative 

Absolute 

Heart 

R. Kidney 

Liver 

Lung 

R. Testis 

Thymus 

Brain 

Necropsy body wt 

Female 

Relative 

Absolute 

Relative 

Absolute 

Relative 

Absolute 

Relative 

Absolute 

Relative 

Absolute 

Relative 

Absolute 

Heart 

R. Kidney 

Liver 

Lung 

Thymus 

5 

24.0 f 0.4 

1.95 f 0.20 

0.047 f 0.004 

4.18 f 0.07 

0.100 f 0.000 

8.35 f 0.14 

0.200 f 0.000 

54.22 f 1.10 

1.300 f 0.032 

8.77 f 0.28 

0.210 f 0.005 

4.76 f 0.22 

0.114 f 0.005 

18.37 f 0.36 

0.440 f 0.003 

20.2 f 0.3 

53.48 f 0.91 

1.080 f 0.020 

7.52 f 0.20 

0.152 f 0.005 

5.35 f 0.09 

0.108 f 0.002 

21.88 f 0.25 

0.442 f 0.007 

2.93 f 0.17 

0.059 f 0.003 

7.87 f 1.13 

0.160 f 0.024 

5 

22.9 f 0.2 

18.52 f 0.28 

0.424 f 0.004 

1.55 f 0.16 

0.036 f 0.004 

4.10 * 0.10 

0.094 f 0.002 

10.48 f 1.06 

0.240 f 0.024 

59.41 f 2.27 

1.360 f 0.051 

8.52 f 0.47 

0.195 f 0.010 

5.24 f 0.14 

0.120 f 0.003 

19.5 f 0.7 

2.81 f 0.40 

0.055 f 0.009 

11.50 f 1.52 

0.220 f 0.020 

57.58 f 0.62 

1.120 f 0.037 

7.09 f 0.20 

0.138 f 0.006 

5.55 f 0.33 

0.108 f 0.007 

22.80 f 0.64 

0.442 f 0.005 

5 

17.5 f 0.4**b 

0.136 f 0.007 

24.60 f 0.91** 

0.430 f 0.016 

0.163 f 0.005** 

7.79 f 0.44** 

0.082 f 0.004** 

22.91 f 0.55** 

0.400 f O.OOO** 

61.55 f 2.66 

1.080 f 0.066* 

9.30 f 0.15 

4.71 f 0.30 

0.76 f 0.06** 

0.013 f 0.001** 

13.2 f 0.5**b 

0.116 f 0.013 

28.89 f 2.10** 

0.378 f 0.015* 

1.30 f 0.21** 

0.017' f 0.003** 

27.16 f 1.26** 

0.360 f 0.024** 

55.43 f 4.17 

0.740 f 0.081** 

9.03 f 0.28** 

0.120 f 0.007** 

8.76 f 0.92** 

5 

17.1 f 0.4**b 

24.48 f 1.13** 

0.416 f 0.012 

0.134 f 0.013 

7.89 f 0.84** 

0.161 f 0.008** 

9.41 f 0.25 

61.02 f 1.20 

1.040 f 0.024** 

21.10 f 1.36** 

0.360 f 0.024** 

0.078 f 0.004** 

4.58 f 0.23 

0.86 f 0.14** 

0.015 f 0.002** 

13.9 f 0.3**b 

27.77 f I.%** 

0.386 f 0.023 

0.122 f 0.012 

8.82 f 0.92** 

9.47 f 0.37** 

0.132 f 0.006** 

54.56 f 3.14 

0.760 f 0.051** 

25.83 f 1.40** 

0.360 f 0.024** 

0.91 f 0.09** 

0.013 f 0.001** 

5 

17.0 f 0.5**b 

0.136 f 0.009 

25.43 f 1.34** 

0.430 f 0.013 

0.161 f 0.009** 

8.06 f 0.67** 

9.44 f 0.38 

0.078 f 0.002** 

21.10 f 2.22** 

0.360 f 0.040** 

57.31 f 5.03 

0.980 f 0.102** 

4.60 i- 0.13 

1.01 f 0.41** 

0.018 f 0.008** 

13.5 f 0.4**b 

0.118 f 0.015 

32.92 f 2.21** 

0.442 f 0.025 

1.48 f 0.23** 

0.020 f 0.003** 

28.44 f 2.13** 

0.380 f 0.020** 

65.24 f 1.55* 

0.880 f 0.037** 

9.15 f 0.28** 

0.123 f 0.005** 

8.81 f 1.14** 

5 

16.5 f 0.4**b 

0.136 f 0.010 

24.11 f 1.01** 

0.396 f 0.014 

0.150 f 0.004** 

8.30 f 0.69** 

9.12 f 0.11 

0.85 * 0.10** 

0.014 f 0.002** 

4.86 f 0.09* 

0.080 f 0.003** 

23.20 f 1.53** 

0.380 f 0.020** 

63.16 f 2.38 

1.040 f 0.051** 

13.2 f O.l**b 

0.104 f 0.004 

32.14 f 0.50** 

0.424 f 0.004 

0.91 f 0.10** 

0.012 f 0.001** 

30.31 f 0.28** 

0.400 f 0.000** 

55.91 f 4.67 

0.740 f 0.068** 

9.12 f 0.36** 

0.120 f 0.005** 

7.87 f 0.26** 

a Organ weights and body weights are given in grams; organ-weight-to-body-weight ratios are given as mg organ weight/g body weight 

** PSO.01 

* Significantly different (PlO.05) from the control group by Williams' or Dunnett's test 

All animals in this exposure group died early 

(mean f standard error). 
322 Nickel Sulfate Hexahydrate, NTP TR 454 

of Nickel Sulfate Hexahydrate" 

Organ Weights and Organ-Weight-to-Body-Weight Ratios for Mice in the 13-Week Inhalation Study 

TABLE F6 

0 mg/m3 0.12 mg/m3 0.25 mg/m3 0.5 mg/m3 1 mg/m3 2 mg/m3 

Brain 

Necropsy body wt 

n 

Male 

Relative 

Absolute 

Relative 

Absolute 

Relative 

Absolute 

Relative 

Absolute 

Relative 

Absolute 

Relative 

Absolute 

Relative 

Absolute 

Heart 

R. Kidney 

Liver 

Lung 

R. Testis 

Thymus 

30.3 f 0.6 

6 

1.12 f 0.08 

0.034 f 0.002 

3.75 f 0.11 

0.113 f 0.002 

6.62 f 0.13 

0.200 f o.oO0 

57.79 f 1.67 

1.750 f 0.062 

9.62 f 0.27 

0.292 f 0.012 

5.51 f 0.27 

0.167 f 0.008 

14.89 f 0.36 

0.450 f 0.007 

30.8 f 0.9 

8 

54.07 f 1.84 

1.663 f 0.073 

9.76 f 0.35 

0.300 f 0.013 

5.25 f 0.16 

0.161 f 0.006 

14.60 f 0.46 

0.446 f 0.007 

0.200 f o.oO0 

1.16 f 0.11 

0.036 f 0.004 

3.83 f 0.10 

0.118 f 0.003 

6.54 f 0.18 

30.0 f 0.4 

10 

1.09 f 0.09 

0.033 f 0.003 

3.87 f 0.13 

0.116 f 0.004 

6.68 f 0.08 

0.200 f 0;Ooo 

53.42 f 0.90 

1.600 f 0.030 

10.54 f 0.24 

0.316 f 0.009 

5.45 f 0.15 

0.163 f 0.004 

14.89 f 0.31 

0.445 f 0.005 

31.0 f 0.8 

10 

1.08 f 0.05 

0.033 f 0.001 

4.21 f 0.59 

0.129 f 0.016 

6.78 f 0.25 

0.210 f 0.010 

56.35 f 1.31 

1.750 f 0.073 

10.61 f 0.23 

0.329 f 0.012 

5.52 f 0.14 

0.171 f 0.006 

15.28 f 0.28 

0.472 f 0.008 

10 

31.8 f 0.9 

13.87 f 0.52 

0.439 f 0.015 

5.63 f 0.19 

0.178 f 0.005 

10.54 f 0.36 

0.334 f 0.012 

56.65 f 0.73 

1.800 f 0.054 

7.87 f 0.49* 

0.250 f 0.017** 

3.47 f 0.32 

0.108 f 0.009 

1.06 f 0.06 

0.034 f 0.002 

10 

30.1 * 1.1 

15.49 f 0.64 

0.460 f 0.005 

5.66 f 0.20 

0.169 f 0.006 

10.05 f 0.45 

0.299 f 0.009 

53.97 f 1.72 

1.610 f 0.041 

10.43 f 0.51** 

0.310 f 0.010** 

3.84 * 0.20 

0.114 f 0.004 

1.27 f 0.10 

0.038 f 0.002 
Organ Weight Analyses 323 

of Nickel Sulfate Hexahydrate (continued) 

Organ Weights and Organ-Weight-to-Body-Weight Ratios for Mice in the 13-Week Inhalation Study 

TABLE F6 

0 mg/m3 0.12 mg/m3 0.25 mg/m3 0.5 mg/m3 1 mg/m3 2 mg/mJ 

Brain 

Necropsy body wt 

n 

Female 

Relative 

Absolute 

Relative 

Absolute 

Relative 

Absolute 

Relative 

Absolute 

Relative 

Absolute 

Relative 

Absolute 

Heart 

R. Kidney 

Liver 

Lung 

Thymus 

1 

25.8 f 0.6 

1.66 f 0.14 

0.042 f 0.003 

7.78 f 0.18 

0.200 f 0.000 

57.64 f 0.75 

1.486 f 0.040 

7.94 f 0.18 

0.204 f 0.005 

5.22 f 0.18 

0.134 f 0.004 

18.12 f 0.37 

0.466 f 0.004 

26.3 f 0.5 

10 

0.200 f 0.000 

57.98 f 1.77 

1.530 f 0.072 

7.67 f 0.12 

0.202 f 0.006 

4.98 f 0.12 

0.131 f 0.004 

17.71 f 0.29 

0.465 f 0.008 

1.52 f 0.10 

0.040 f 0.002 

7.63 f 0.16 

27.1 f 0.6 

10 

1.68 f 0.06 

0.045 f 0.001 

7.40 f 0.14 

0.200 f 0.000 

54.78 f 1.18 

1.490 f 0.057 

7.45 f 0.13 

0.202 f 0.006 

4.93 f 0.08 

0.134 f 0.004 

17.25 f 0.23 

0.467 f 0.004 

26.0 f 0.3 

10 

0.200 f 0.000 

57.27 f 0.76 

1.490 f 0.028 

8.04 f 0.15 

0.209 f 0.004 

5.27 f 0.15 

0.137 f 0.004 

17.78 f 0.27 

0.462 f 0.005 

1.72 f 0.11 

0.045 f 0.002 

7.70 f 0.09 

26.3 f 0.4 

10 

1.66 f 0.10 

0.044 f 0.003 

8.42 f 0.59 

0.220 f 0.013 

54.44 f 0.65 

1.430 f 0.021 

7.57 f 0.17 

0.199 f 0.005 

4.98 f 0.10 

0.131 f 0.003 

17.92 f 0.33 

0.470 f 0.003 

24.1 f 0.5 

10 

1.54 f 0.07 

0.038 f 0.001 

10.94 f 0.55** 

0.270 f 0.015** 

54.75 f 0.62 

1.350 f 0.034 

7.92 f 0.13 

0.195 f 0.004 

5.34 f 0.16 

0.131 f 0.003 

18.85 f 0.38 

0.463 f 0.005 

a Organ weights and body weights are given in grams; organ-weight-to-body-weight ratios are given as mg organ weightfg body weight 

** P<O.Ol 

* Significantly different (PSO.05) from the control group by Williams’ or Dunnett’s test 

(mean f standard error). 
324 Nickel Sulfate Hexahydrate, NTP TR 454 

in the 2-Year Inhalation Study of Nickel Sulfate Hexahydratea 

Organ Weights and Organ-Weight-to-Body-Weight Ratios for Mice at the 7-Month Interim Evaluation 

TABLE M 

0 mg/m3 0.25 mg/m3 0.5 mg/m3 1 mg/m3 

Brain 

Necropsy body wt 

Male 

n 

Relative 

Absolute 

Relative 

Absolute 

Relative 

Absolute 

Relative 

Absolute 

Relative 

Absolute 

Relative 

Absolute 

Relative 

Absolute 

R. Kidney 

Liver 

Lung 

Spleen 

R. Testis 

Thymus 

Brain 

Necropsy body wt 

Female 

Relative 

Absolute 

Relative 

Absolute 

Relative 

Absolute 

Relative 

Absolute 

Relative 

Absolute 

Relative 

Absolute 

R. Kidney 

Liver 

Lung 

Spleen 

Thymus 

5 

35.6 f 1.1 

13.47 f 0.50 

0.478 f 0.005 

1.10 f 0.03 

0.039 f 0.002 

3.49 f 0.12 

0.124 f 0.004 

2.31 f 0.22 

0.082 f 0.007 

5.94 f 0.08 

0.212 f 0.009 

49.23 f 1.61 

1.752 f 0.064 

11.39 f 0.32 

0.406 f 0.017 

32.6 f 1.6 

3.34 f 0.24 

0.108 f 0.007 

6.69 f 0.60 

0.218 f 0.022 

48.82 f 1.54 

1.582 f 0.044 

7.27 f 0.30 

0.236 f 0.012 

14.41 f 0.57 

0.466 f 0.010 

1.49 f 0.06 

0.049 f 0.004 

5 

36.5 f 2.5 

0.94 f 0.12 

0.034 f 0.004 

3.53 f 0.12 

0.128 f 0.006 

2.35 f 0.31 

0.084 f 0.009 

5.60 f 0.18 

0.204 f 0.013 

52.11 f 3.05 

1.876 f 0.053 

11.32 f 0.43 

0.410 f 0.016 

13.13 f 0.77 

0.472 f 0.007 

32.5 f 1.2 

14.40 f 0.76 

0.464 f 0.007 

47.70 f 1.10 

1.544 f 0,033 

8.31 f 0.97 

0.270 f 0.035 

1.22 f 0.10 

0.040 f 0.004 

3.08 f 0.16 

0.100 f 0.007 

6.54 f 0.50 

0.212 f 0.017 

5 

35.7 f 0.5 

0.96 f 0.11 

0.034 f 0.004 

3.42 f 0.11 

0.122 f 0.004 

2.30 f 0.11 

0.082 i 0.004 

6.17 f 0.33 

0.220 f 0.011 

50.27 f 2.67 

1.794 f 0.089 

10.97 f 0.29 

0.392 f 0.012 

12.94 f 0.25 

0.462 f 0.008 

30.1 f 0.8 

7.90 f 0.25 

0.238 f 0.010 

15.73 f 0.48 

0.472 f 0.006 

51.48 f 1.01 

1.548 f 0.038 

7.16 f 0.24 

0.216 f 0.012 

3.19 f 0.14 

0,096 f 0.005 

1.41 f 0.07 

0.042 f 0.002 

5 

35.8 f 0.5 

12.69 f 0.23 

0.454 f 0.010 

1.01 f 0.14 

0.036 f 0.005 

3.47 f 0.10 

0.124 f 0.002 

2.74 f 0.45 

0.098 f 0.016 

6.48 f 0.21 

0.232 f 0.009 

46.41 f 1.35 

1.660 f 0.048 

10.68 f 0.41 

0.382 f 0.014 

29.9 f 0.8 

8.29 f 0.09 

0.248 f 0.006 

16.21 f 0.35 

0.484 f 0.005 

50.72 f 0.85 

1.518 f 0.050 

3.61 f 0.12 

0.108 f 0.005 

8.42 f O.IR* 

0.252 f 0.009 

1.36 f 0.16 

0.041 f 0.005 

* Significantly different (P 50.05) from the control group by Williams’ or Dunnett’s test a Organ weights and body weights are given in grams; organ-weight-to-body-weight ratios are given as mg organ weight/g body weight (mean f standard 

error). 
Organ Weight Analyses 325 

in the 2-Year Inhalation Study of Nickel Sulfate Hexahydratea 

Organ Weights and Organ-Weight-to-Body-Weight Ratios for Mice at the 15-Month Interim Evaluation 

TABLE F8 

Brain 

Necropsy body wt 

Male 

n 

Relative 

Absolute 

Relative 

Absolute 

Relative 

Absolute 

Relative 

Absolute 

Relative 

Absolute 

Relative 

Absolute 

R. Kidney 

Liver 

Lung 

Spleen 

Thymus 

Brain 

Necropsy body wt 

Female 

Relative 

Absolute 

Relative 

Absolute 

Relative 

Absolute 

Relative 

Absolute 

Relative 

Absolute 

Relative 

Absolute 

R. Kidney 

Liver 

Lung 

Spleen 

Thymus 

5 

39.5 f 1.3 

1.06 f 0.14 

0.042 f 0.006 

2.46 f 0.20b 

0.096 f 0.005b 

6.19 f 0.63 

0.242 f 0.020 

53.80 f 4.90 

2.108 f 0.156 

11.25 f 0.90 

0.440 f 0.024 

12.04 f 0.65 

0.472 f 0.012 

39.6 f 2.5 

12.39 f 0.71 

0.484 f 0.010 

1.21 f 0.13 

0.048 f 0.006 

4.34 f 0.89 

0.166 f 0.028 

6.17 f 0.54 

0.240 f 0.014 

48.27 f 3.33 

1.890 f 0.102 

7.98 f 0.74 

0.310 f 0.017 

5 

41.0 f 0.8 

0.84 f 0.07 

0.034 f 0.002 

1.85 f 0.14 

0.076 f 0.007 

6.13 f 0.22 

0.252 f 0.013 

48.73 f 2.38 

1.996 f 0.086 

10.84 f 1.06 

0.444 f 0.043 

11.56 f 0.21 

0.474 f 0.009 

37.4 f 1.3 

3.42 f 0.54 

0.126 f 0.017 

6.50 f 0.39 

0.242 f 0.013 

48.63 f 2.17 

1.810 f 0.058 

7.45 f 0.33 

0.278 f 0.014 

13.22 f 0.44 

0.492 f 0.005 

1.22 f 0.14 

0.045 f 0.004 

5 

41.1 f 1.8 

0.85 f 0.07 

0.035 f 0.002 

2.34 f 0.35 

0.094 f 0.011 

6.38 f 0.44 

0.260 f 0.013 

52.28 f 2.76 

2.132 f 0.063 

11.19 f 0.73 

0.456 f 0.019 

11.82 f 0.51 

0.482 f 0.006 

42.6 f 4.8 

6.67 f 0.53 

0.276 f 0.015 

49.45 f 4.56 

2.040 f 0.105 

7.04 f 0.47 

0.292 f 0.012 

11.71 f 1.12 

0.478 f 0.012 

3.19 f 0.50 

0.130 f 0.014 

1.26 f 0.16 

0.055 f 0.013 

5 

42.6 f 1.9 

11.42 f 0.61 

0.482 f 0.007 

10.63 f 1.03 

0.448 f 0.034 

50.53 f 3.78 

2.132 f 0.115 

0.306 f 0.012** 

7.23 f 0.36 

2.44 f 0.46 

0.102 f 0.017 

0.94 f 0.13 

0.041 f 0.007 

34.2 f 0.9 

14.54 f 0.51 

0.496 f 0.007 

7.82 f 0.44 

0.266 f 0.009 

52.03 f 1.46 

1.778 f 0.040 

9.57 f 0.64** 

0.326 f 0.016** 

3.72 f 0.23 

0.128 f 0.010 

1.28 f 0.17 

0.044 f 0.007 

a Organ weights and body weights are given in grams; organ-weight-to-body-weight ratios are given as mg organ weightlg body weight (mean f standard 

** Significantly different (P~0.01) from the control group by Williams’ or Dunnett’s test 

n=4 

error). 
326 Nickel Sulfate Hexahydrate, NTP TR 454 
327 

HEMATOLOGY RESULTS 

APPENDIX G 

TABLE 64 Hematology Data for Mice at the 15-Month Interim Evaluation 

TABLE G3 Hematology Data for Mice in the 13-Week Inhalation Study 

TABLE 62 Hematology Data for Rats at the 15-Month Interim Evaluation 

TABLE G1 Hematology Data for Rats in the 13-Week Inhalation Study 

in the 2-Year Inhalation Study of Nickel Sulfate Hexahydrate 

of Nickel Sulfate Hexahydrate 

in the 2-Year Inhalation Study of Nickel Sulfate Hexahydrate 

of Nickel Sulfate Hexahydrate ..................................... 

333 

331 

330 

328 

................ 

..................................... 

................ 
328 Nickel Sulfate Hexahydrate, NTP TR 454 

TABLE G1 

Hematology Data for Rats in the 13-Week Inhalation Study of Nickel Sulfate Hexahydratea ~~ 

0 mg/m3 0.12 mg/m3 0.25 mg/m3 0.5 mg/m3 1 mg/m’ 2 mg/m3 

Male 

n 10 10 

Nucleated erythrocytes (103/pL) 

Eosinophils (103/pL) 

Monocytes (103/pL) 

Lymphocytes (103/pL) 

Segmented neutrophils ( 103/pL) 

Leukocytes (103/pL) 

Reticulocytes ( 106/pL) 

Mean cell hemoglobin concentration (gldL) 

Mean cell volume (E) 

Erythrocytes (106/pL) 

Hemoglobin (g/dL) 

Hematocrit (%) 

44.5 f 0.5 44.3 f 0.5 

15.4 f 0.2 15.6 f 0.1 

8.45 f 0.10 8.55 f 0.08 

53.4 f 0.2 52.6 f.O.3 

34.5 f 0.1 35.1 f 0.2* 

0.6 f 0.0 0.7 f 0.1 

2.72 f 0.20 2.60 f 0.24 

0.69 f 0.07 0.66 f 0.07 

1.96 f 0.14 1.85 f 0.16 

0.04 f 0.01 0.05 f 0.02 

0.03 f 0.01 6.04 f 0.02 

0.07 f 0.01 0.09 f 0.02 

10 

35.5 f 0.2** 

52.3 f 0.2 

8.77 f 0.08 

16.0 f 0.1* 

45.1 f 0.3 

0.06 f 0.02 

0.01 f 0.01 

0.06 f 0.02 

2.40 f 0.23 

0.97 f 0.12 

3.44 f 0.29 

0.5 f 0.1 

10 

35.3 f 0.2** 

52.4 f 0.4 

8.57 f 0.09 

15.6 f 0.1 

44.4 f 0.5 

0.09 f 0.02 

0.02 f 0.01 

0.06 f 0.04 

1.70 f 0.21 

0.90 f 0.11 

2.67 f 0.32 

0.4 f 0.1 

10 

35.2 f 0.2** 

53.1 f 0.8 

8.55 f 0.09 

15.7 f 0.1 

44.6 f 0.4 

0.06 f 0.01 

0.00 f 0.00 

0.05 f 0.01 

1.52 f 0.16 

1.04 f 0.12* 

2.63 f 0.27 

0.6 f 0.1 

9 

35.9 f 0.4** 

52.2 f 0.2* 

8.57 f 0.16 

15.8 f 0.2 

44.2 f 0.9 

0.12 f 0.06 

0.05 f 0.02 

0.04 f 0.01 

2.07 f 0.17 

1.33 f 0.09** 

3.49 f 0.24 

0.4 f 0.1 
Hematology 329 

Hematology Data for Rats in the 13-Week Inhalation Study of Nickel Sulfate Hexahydrate (continued) 

TABLE G1 

0 mg/m3 0.12 mg/m3 0.25 mg/m3 0.5 mg/m3 1 mg/m3 2 mg/m3 

Female 

n 10 10 

Nucleated erythrocytes ( 103/pL) 

Eosinophils (103/pL) 

Monocytes (103/pL) 

Lymphocytes (lO’lpL) 

Segmented neutrophils ( 103/pL) 

Leukocytes (103/pL) 

Reticulocytes (106/pL) 

Mean cell hemoglobin concentration (g/dL) 

Mean cell volume (fL) 

Erythrocytes (106/pL) 

Hemoglobin (g/dL) 

Hematocrit (X) 

34.9 f 0.2 34.8 f 0.1 

56.7 f 0.2 56.5 f 0.2 

7.31 f 0.17 7.42 f 0.07 

14.2 f 0.3 14.4 f 0.1 

40.9 f 1.0 41.3 f 0.4 

0.06 f 0.02 0.07 f 0.02 

0.05 f 0.02 0.03 f 0.01 

0.03 f 0.01 0.02 f 0.01 

1.97 f 0.25 2.11 f 0.28 

0.40 f 0.08 0.42 f 0.06 

2.45 f 0.33 2.59 f 0.33 

0.3 f 0.0 0.5 f O.O* 

10 

39.3 f 1.8 

34.9 f 0.1 

56.4 f 0.3 

7.06 f 0.32 

13.7 f 0.6 

0.14 f 0.03 

0.05 f 0.01 

0.04 f 0.02 

2.13 f 0.14 

0.79 f 0.11 ** 

3.01 f 0.23 

0.5 f 0.1* 

10 

34.7 f 0.1 

57.1 f 0.2 

7.43 f 0.06 

14.5 f 0.1 

41.8 f 0.3 

0.09 * 0.02 

0.02 f 0.01 

0.06 f 0.02 

2.57 f 0.23 

1.03 f 0.09** 

3.68 f 0.29* 

0.5 f 0.1** 

10 

34.8 f 0.1 

57.4 f 0.3 

7.59 f 0.05* 

14.9 f 0.1** 

42.8 f 0.4* 

0.18 f 0.04* 

0.02 f 0.02 

0.06 f 0.01 

3.26 f 0.16** 

1.08 f 0.05** 

4.42 f 0.16** 

0.5 f 0.1** 

10 

34.8 f 0.1 

56.5 f 0.2 

7.57 f 0.07* 

14.7 f 0.2* 

42.3 f 0.4 

0.09 f 0.03 

0.03 f 0.01 

0.08 f 0.01* 

3.07 f 0.28** 

1.13 f 0.14** 

4.31 f 0.41** 

0.6 f 0.1** 

a Mean f standard error; statistical tests were performed on unrounded data. 

** PSO.01 

* Significantly different (PSO.05) from the control group by Dunn’s or Shirley’s test 
330 Nickel Sulfate Hexahydrate, NTP TR 454 

of Nickel Sulfate Hexahydratea 

Hematology Data for Rats at the 15-Month Interim Evaluation in the 2-Year Inhalation Study 

TABLE 62 

O mg/m3 0.12 mg/m3 0.25 mg/m3 0.5 mg/m’ 

Male 

n 

Mean cell hemoglobin 

Mean cell hemoglobin (pg) 

Mean cell volume (fL) 

Erythrocytes (1061pL) 

Hemoglobin (g/dL) 

Hematocrit (%) 

Nucleated erythrocytes (103/pL) 

Eosinophils (lO’/pL) 

Monocytes (103/pL) 

Lymphocytes (103/pL) 

Segmented neutrophils (103/pL) 

Leukocytes (103/pL) 

Reticulocytes ( 106/pL) 

concentration (gIdL) 

Female 

n 

Mean cell hemoglobin 

Mean cell hemoglobin (pg) 

Mean cell volume (a) 

Erythrocytes (106/pL) 

Hemoglobin (gIdL) 

Hematocrit ( W) 

Nucleated erythrocytes (103/pL) 

Eosinophils ( 103/pL) 

Monocytes (103/pL) 

Lymphocytes (10 IpL) 

Segmented neutro hils (103/pL) 

Leukocytes (103/pL) 

Reticulocytes (106/pL) 

concentration (gIdL) 

P 

5 

18.4 f 0.1 

55.0 f 0.3 

8.39 f 0.11 

15.4 f 0.2 

46.5 f 0.6 

0.00 f 0.00 

0.16 f 0.04 

0.16 f 0.05 

3.72 f 0.24 

1.56 f 0.12 

5.60 f 0.27 

0.3 f 0.1 

33.2 f 0.2 

5 

19.4 f 0.8 

62.2 f 2.0 

8.02 f 0.48 

15.4 f 0.2 

50.5 f 4.7 

0.04 f 0.02 

0.04 f 0.02 

0.24 f 0.07 

3.42 f 0.17 

0.98 f 0.08 

4.68 f 0.19 

0.3 f 0.1 

31.2 f 2.0 

5 

18.3 f 0.2 

54.6 f 0.2 

8.66 f 0.13 

15.8 f 0.1 

47.7 f 0.6 

0.02 f 0.01 

0.08 f 0.02 

0.22 f 0.05 

3.80 f 0.36 

2.02 f 0.37 

6.12 f 0.60 

0.3 f 0.0 

33.3 f 0.3 

5 

20.3 f 0.3 

60.8 f 0.9 

7.86 f 0.12 

15.5 f 0.2 

46.5 f 1.0 

33.3 f 0.3 

0.03 f 0.03b 

0.02 f 0.02 

0.23 f 0.13b 

3.18 f 0.30b 

1.08 f 0.2b 

4.50 f 0.53b 

0.2 f O.Ob 

4 

18.2 f 0.3 

55.8 f 0.8 

8.69 f 0.15 

15.9 f 0.1 

48.6 f 0.5* 

0.09 f 0.04* 

0.08 f 0.03 

0.23 f 0.03 

3.58 f 0.21 

1.58 f 0.27 

5.45 f 0.22 

0.3 f 0.1 

32.6 f 0.3 

5 

19.9 f 0.2 

62.0 f 2.3 

7.61 f 0.17 

15.2 f 0.3 

47.3 f 1.6 

0.01 f 0.01 

0.02 f 0.02 

0.18 f 0.07 

3.56 f 0.42 

0.98 f 0.14 

4.72 f 0.56 

0.4 f 0.2 

32.1 f 0.9 

5 

18.3 f 0.2 

55.6 f 0.6 

8.69 f 0.16 

15.8 f 0.2 

48.5 f 1.2 

0.04 f 0.02 

0.10 f 0.00 

0.22 f 0.04 

3.50 f 0.14 

1.72 f 0.12 

5.52 f 0.20 

0.3 f 0.0 

32.7 f 0.6 

3 

20.3 f 0.0 

60.0 f 0.6 

7.97 f 0.07 

16.1 f 0.2 

47.9 f 0.1 

0.04 f 0.01 

0.07 f 0.03 

0.10 f 0.06 

2.87 f 0.38 

1.17 f 0.29 

4.20 f 0.64 

0.3 f 0.0 

33.7 f 0.5 

* Significantly different (PSO.01) from the control group by Dun” or Shirley’s test a Mean f standard error; statistical tests were performed on unrounded data. 

b=4 
Hematology 331 

Hematology Data for Mice in the 13-Week Inhalation Study of Nickel Sulfate Hexahydratea 

TABLE 63 

0 mg/m3 0.12 mg/m’ 0.25 mgh3 0.5 mg/mJ 1 mg/d 2 mg/m3 

n 

Male 

2 5 

Nucleated erythrocytes ( 103/pL) 

Eosinophils (103/pL) 

Monocytes (103/pL) 

Lymphocytes (103/pL) 

Segmented neutrophils ( 103/pL) 

Leukocytes (103/pL) 

Reticulocytes (106/pL) 

Mean cell hemoglobin concentration (g/dL) 

Mean cell volume (fL) 

Erythrocytes (106/pL) 

Hemoglobin (gldL) 

Hematocrit (%) 

40.9 f 1.0 36.3 f 2.3 

14.9 f 0.7 13.1 f 0.9 

8.22 f 0.15 6.90 f 0.63 

50.5 f 0.5 54.0 f 2.2 

36.3 f 0.7 35.9 f 0.6 

0.5 f 0.2 0.7 f 0.1 

1.30 f 0.40 1.46 f 0.26 

0.65 f 0.07 0.66 f 0.17 

0.64 f 0.31 0.79 f 0.14 

0.00 f 0.00 0.00 f 0.00 

0.02 f 0.02 0.01 f 0.01 

0.02 f 0.00 0.02 f 0.01 

4 

37.0 f 0.4 

53.5 f 2.0 

7.69 f OS2 

14.9 f 0.1 

40.2 f 1.6 

0.08 f 0.07 

0.00 f 0.00 

0.05 f 0.02 

2.06 f 0.43 

0.64 f 0.08 

2.15 f 0.47 

0.7 f 0.2 

5 

36.3 f 0.3 

51.2 f 0.6 

8.36 f 0.11 

15.3 * 0.3 

42.3 f 0.9 

0.01 f 0.00 

0.00 f 0.00 

0.00 f 0.00 

0.42 f 0.11 

0.43 f 0.19 

0.86 f 0.28 

0.3 f 0.1 

5 

36.1 f 0.2 

53.0 f 1.6 

8.04 f 0.43 

15.1 f 0.5 

41.9 f 1.4 

0.02 f 0.01 

0.01 f 0.01 

0.06 f 0.05 

0.86 f 0.45 

0.48 f 0.22 

1.42 f 0.73 

0.6 f 0.1 

5 

35.9 f 1.0 

50.0 f 0.3 

8.18 f 0.48 

14.4 f 0.6 

40.4 f 2.5 

0.06 f 0.04 

0.01 f 0.01 

0.04 f 0.02 

1.12 f 0.21 

0.45 f 0.09 

1.62 f 0.26 

0.7 f 0.1 
332 Nickel Sulfate Hexahydrate, NTP TR 454 

Hematology Data for Mice in the 13-Week Inhalation Study of Nickel Sulfate Hexahydrate (continued) 

TABLE 63 

0 mg/m3 0.12 mg/m3 0.25 mg/m3 0.5 mg/m3 1 mg/m3 2 mg/m3 

n 

Female 

7 10 

Nucleated erythrocytes (lO’/pL) 

Eosinophils (103/pL) 

Monocytes (103/pL) 

Lymphocytes (103/pL) 

Segmented neutrophils (103/pL) 

Leukocytes (103/pL) 

Reticulocytes ( 106/pL) 

Mean cell hemoglobin concentration (g/dL) 

Mean cell volume (fL) 

Erythrocytes (106/pL) 

Hemoglobin (gldL) 

Hematocrit (%) 

39.9 f 1.1 38.4 f 1.3 

14.4 f 0.3 14.1 f 0.5 

7.89 f 0.23 7.61 f 0.27 

51.1 f 0.4 51.0 f 0.3 

36.2 f 0.5 36.5 f 0.2 

0.3 f 0.1 0.5 f 0.1 

1.66 f 0.15 1.70 f 0.10 

0.28 f 0.04 0.36 f 0.09 

1.33 f 0.13 1.30 f 0.09 

0.02 f 0.01 0.01 f 0.00 

0.03 f 0.01 0.03 f 0.01 

0.01 f 0.01 0.04 f 0.01 

10 

0.4 f 0.1 

36.2 f 0.3 

50.9 f 0.2 

8.03 f 0.11 

14.6 f 0.2 

40.4 f 0.5 

0.06 f 0.02 

0.03 f 0.01 

0.01 f 0.01 

1.27 f 0.09 

0.33 f 0.04 

1.64 f 0.12 

10 

2.15 f 0.19 

0.4 f 0.1 

36.1 f 0.5 

51.2 f 0.4 

8.09 f 0.11 

14.8 f 0.2 

40.9 f 0.7 

0.05 f 0.02 

0.02 f 0.01 

0.02 f 0.01 

1.56 f 0.17 

0.54 f 0.08** 

10 

0.3 f 0.0 

37.0 f 0.3 

51.0 f 0.3 

8.11 f 0.11 

15.1 f 0.1** 

40.8 f 0.5 

2.60 f 0.24** 

0.59 f 0.09* 

0.07 f 0.03 

0.04 f 0.01 

0.02 f 0.01 

1.95 f 0.17* 

10 

0.3 f 0.0 

36.4 f 0.2 

50.9 f 0.2 

8.15 f 0.11 

14.9 f 0.3* 

40.9 f 0.6 

0.09 f 0.02* 

0.05 * 0.02 

0.03 f 0.01 

1.95 f 0.11* 

0.49 f 0.05* 

2.52 f 0.13** 

a Mean f standard error; statistical tests were performed on unrounded data. 

** P 10.01 

* Significantly different (PlO.05) from the control group by DUM’S or Shirley’s test 
Hematology 333 

of Nickel Sulfate Hexahydratea 

Hematology Data for Mice at the 15-Month Interim Evaluation in the 2-Year Inhalation Study 

TABLE 64 

O mg/m3 0.25 mg/m3 0.5 mg/m3 1 mg/m3 

Male 

n 

Mean cell hemoglobin 

Mean cell hemoglobin (pg) 

Mean cell volume (a) 

Erythrocytes (106/pL) 

Hemoglobin (g/dL) 

Hematocrit (%) 

Nucleated erythrocytes (103/pL) 

Eosinophils (103/pL) 

Monocytes (103/pL) 

Lymphocytes ( 103/pL) 

Segmented neutrophils ( 10S/pL) 

Leukocytes (103/pL) 

Reticulocytes (106/pL) 

concentration (g/dL) 

Female 

n 

Mean cell hemoglobin 

Mean cell hemoglobin (pg) 

Mean cell-volume (a) 

Erythrocytes (106/pL) 

Hemoglobin (g/dL) 

Hematocrit (96) 

Nucleated erythrocytes (103/pL) 

Eosinophils (103/pL) 

Monocytes (103/pL) 

Lymphocytes (10 IpL) 

Segmented neutro hils (1031pL) 

Leukocytes (10~1~~) 

Reticulocytes (106/pL) 

concentration (g/dL) 

P 

5 

16.1 f 0.2 

49.4 f 0.4 

9.30 f 0.32 

15.0 f 0.4 

46.2 f 1.3 

0.00 f 0.00 

0.04 f 0.02 

0.07 f 0.02 

2.83 f 0.54 

1.85 f 0.39 

4.80 f 0.83 

0.1 f 0.0 

32.4 f 0.4 

5 

16.2 f 0.3 

48.6 f 0.2 

8.94 f 0.24 

14.5 f 0.6 

43.9 f 1.3 

0.00 f 0.00 

0.02 f 0.02 

0.20 f 0.11 

2.62 f 0.76 

1.70 f 0.56 

4.60 f 1.16 

0.1 f 0.0 

33.0 f 0.3 

4 

16.8 f 0.2 

50.0 f 0.6 

8.83 f 0.14 

14.8 f 0.2 

44.5 f 0.5 

0.00 f 0.00 

0.00 f 0.00 

0.05 f 0.03 

2.13 f 0.14 

1.10 f 0.20 

3.30 f 0.25 

0.1 f 0.0 

33.3 f 0.1 

5 

16.5 f 0.2 

49.8 f 0.7 

8.74 f 0.14 

14.4 f 0.3 

43.9 f 0.2 

0.00 f 0.00 

0.06 f 0.02 

0.08 f 0.04 

1.70 f 0.24 

1.28 f 0.47 

3.12 f 0.70 

0.2 f 0.0 

32.7 f 0.4 

5 

16.7 f 0.2 

50.8 f 0.4 

8.50 f 0.37 

14.2 f 0.7 

43.5 f 2.0 

0.00 f 0.00 

0.08 f 0.02 

0.06 f 0.02 

2.28 f 0.27 

1.18 f 0.34 

3.64 f 0.56 

0.1 f 0.0 

32.7 f 0.3 

5 

16.1 f 0.2 

49.4 f 0.8 

9.64 f 0.28 

15.4 f 0.3 

47.6 f 0.9 

0.01 f 0.01 

0.04 f 0.02 

0.08 f 0.03b 

1.65 f 0.06b 

0.83 f O.lOb 

2.55 f 0.05b 

0.1 f 0.0 

32.4 f 0.5 

5 

16.9 f 0.1* 

51.6 f 0.9 

8.29 f 0.42 

14.0 f 0.7 

43.0 f 2.1 

0.00 f 0.00 

0.06 f 0.02 

0.16 f 0.11 

2.26 f 0.26 

1.84 f 0.47 

4.32 f 0.68 

0.2 f 0.1 

32.6 f 0.5 

5 

16.3 f 0.2 

49.4 f 0.2 

8.56 f 0.49 

14.0 f 0.9 

42.7 f 2.4 

0.02 f 0.01 

0.02 f 0.02 

0.14 f 0.04 

1.84 f 0.38 

1.14 f 0.37 

3.16 f 0.50 

0.1 f 0.0 

32.7 f 0.3 

* Significantly different (PlO.05) from the control group by Dum’s or Shirley’s test a Mean f standard error; statistical tests were performed on unrounded data. 

n=4 
334 Nickel Sulfate Hexahydrate, NTP TR 454 
335 

TISSUE BURDEN IN RATS 

APPENDIX H 

TABLE H5 Lung Weight and Lung Burden in Rats in the 2-Year Inhalation Study 

TABLE H4 Kidney Burden in Rats in the 13-Week Inhalation Study 

TABLE H3 Lung Weight and Lung Burden in Rats in the 13-Week Inhalation Study 

TABLE H2 Kidney Weight and Kidney Burden in Rats in the 16-Day Inhalation Study 

TABLE H1 Lullg Weight and Lung Burden in Rats in the 16-Day Inhalation Study 

of Nickel Sulfate Hexahydrate 

of Nickel Sulfate Hexahydrate 

of Nickel Sulfate Hexahydrate 

of Nickel Sulfate Hexahydrate 

of Nickel Sulfate Hexahydrate ..................................... 

339 

338 

337 

336 

336 

..................................... 

..................................... 

..................................... 

..................................... 
336 Nickel Sulfate Hexahydrate, NTP TR 454 

Lung Weight and Lung Burden in Rats in the 16-Day Inhalation Study of Nickel Sulfate Hexahydratea 

TABLE H1 

0 mg/m3 3.5 mg/m3 15 mg/m3 30 mg/m3 

Male 

n 5 5 4 5 

pg Nilg control lung 

pg Nilg lung 

pg Nulung 

Absolute lung wt (g) 

7.300 f 0.355** 13.650 f 1.436** 10.560 f 1.643** 

5.100 f 0.318** 9.425 f 1.055** 7.700 f 1.190** 

6.700 f 0.326** 12.575 f 1.326** 9.700 f 1.522** 

0.920 f 0.034 1.322 f 0.043** 1.353 f 0.084** 1.262 f 0.027** - 

b 

- 

- 

Female 

n 5 5 5 4 

pg Nilg control lung 

pg Ni/g lung 

pg Nillung 

Absolute lung wt (g) 

10.060 f 0.434** 17.060 f 1.694** 13.025 f 3.355** 

7.640 f 0.333** 10.500 f 1.063** 9.225 f 2.415** 

9.400 f 0.517** 12.980 f 1.293** 9.900 f 2.539** 

0.762 f 0.038 1.230 f 0.039** 1.244 f 0.026** 1.075 f 0.032** - 

- 

- 

a Mean f standard error; statistical tests were performed on unrounded data. 

** Significantly different (P10.01) from the control group by Dunnett’s test (lung weight) or Shirley’s test (lung burden parameters) 

Results were below 0.155 pg Ni (the limit of detection), or below the level of quantitation. 

of Nickel Sulfate Hexahydratea 

Kidney Weight and Kidney Burden in Rats in the 16-Day Inhalation Study 

TABLE II2 

0 mg/m3 30 mg/m3 

Male 

n 

pg Nilg kidney 

pg Nilkidney 

Absolute kidney wt (g) 

Female 

n 

pg Nilg kidney 

pg Ni/kidney 

Absolute kidney wt (g) 

5 

1.80 f 0.07 - 

b 

5 

1.32 f 0.04 - 

- 

5 

1.880 f 0.276** 

2.080 f 0.298** 

1.11 f 0.04** 

4 

1.783 f 0.226** 

1.600 f 0.193** 

0.90 f 0.03** 

a Mean f standard error; statistical tests were performed on unrounded data. 

** Significantly different (P10.01) from the control group by Williams’ or Dunnett’s test (kidney weight) or Shirley’s test (kidney burden 

Results were below 0.155 pg Ni (the limit of detection), or below the level of quantitation. 

parameters) 
Tissue Burden in Rats 337 

Lung Weight and Lung Burden in Rats in the 13-Week Inhalation Study of Nickel Sulfate Hexahydratea 

TABLE H3 

n 

Male 

4 weeks 

pg Nilg control lung 

pg Nilg lung 

9 weeks 

pg Nilg control lung 

pg Ni/g lung 

13 weeks 

pg Nilg control lung 

pg Ni/g lung 

pg Nillung 

Absolute lung wt (9) 

Female 

13 weeks 

pg Nilg control lung 

pg Ni/g lung 

pg Ni/lung 

Absolute lung wt (8) 

6 

- 

- 

- 

- 

0.140 f 0.140 

0.120 f 0.120 

0.145 f 0.145 

1.09 f 0.06 

0.835 f 0.033 - 

- 

- 

6 

1.693 f 0.200** 

1.357 f 0.135** 

2.695 f 0.065** 

2.153 f 0.086** 

1.450 f 0.158** 

1.055 f 0.075** 

1.490 f 0.163** 

1.39 f 0.07** 

1.765 f 0.104** 

1.157 f 0.050** 

1.395 f 0.083** 

1.201 f 0.034** 

6 

4.562 f 0.240**' 

2.696 f 0.124**' 

8.348 f 0.446** 

4.770 f 0.207** 

6.368 f 0.161** 

3.348 f 0.067** 

6.557 f 0.166** 

1.96 f 0.06** 

6.897 f 0.486** 

3.725 f 0.270** 

5.460 f 0.384** 

1.469 f 0.040** 

- 

' n=5 

a Mean f standard error; statistical tests were performed on unrounded data. 

** Significantly different (P50.01) from the control group by Williams' test (lung weight) or Shirley's test (lung burden parameters) 

Results were below 0.216 pg Ni (the limit of detection), or below the level of quantitation. 
338 Nickel Sulfate Hexahydrate, NTP TR 454 

Kidney Burden in Rats in the 13-Week Inhalation Study of Nickel Sulfate Hexahydratea 

TABLE H4 

0 mg/m3 0.5 mg/m3 2 mg/m3 

n 

Male 

4 weeks 

pg Nilg kidney 

9 weeks 

pg Nilg kidney 

13 weeks 

pg Ni/g kidney 

Female 

13 weeks 

pg Nilg kidney 

6 6 6 

0.118 f 0.118 0.228 f 0.142' 

0.535 f 0.377 0.065 f 0.065 

0.112 f 0.112 0.400 f 0.124 

- 0.065 f 0.065 

a Mean f standard error; statistical tests were performed on unrounded data. 

n=5 

Results were below 0.216 pg Ni (the limit of detection), or below the level of quantitation. 
Tissue Burden in Rats 339 

Lung Weight and Lung Burden in Rats in the 2-Year Inhalation Study of Nickel Sulfate Hexahydratea 

TABLE H5 

0 mg/m3 0.12 mg/m3 0.25 mg/m3 0.5 mg/m3 

Male 

n 6 7 7 7 

pg Nilg control lung 

pg Nilg lung 

pg Ni/lung 

Absolute lung wt (g) 

7-Month interim evahation 

1.64 f 0.09 - 

b 

1.64 f 0.06 - 

- 

- 

1.61 f 0.05 - 

- 

- 

1.77 f 0.07 

0.868 f 0.051** 

0.804 f 0.031** 

1.426 f 0.084** 

n 4 5 5 4 

pg Nilg control lung 

pg Nilg lung 

pg Nillung 

Absolute lung wt (g) 

15-Month interim evaluation 

1.688 f 0.257** 

1.268 f 0.205** 

3.575 f 0.545** 

3.00 f 0.26**‘ 

0.177 f 0.018* 

0.151 f 0.015* 

0.374 f 0.038* 

2.48 f 0.10 2.50 f 0.11 

0.528 f 0.061** 

0.448 f 0.049** 

1.117 f 0.128** 

Female 

n 7 7 6 5 

pg Nilg control lung 

pg Nilg lung 

pg Nillung 

Absolute lung wt (9) 

7-Month interim evaluation 

1.13 f 0.04 

- 

- 

- 

1.21 f 0.04 

- 

- 

- 

1.10 f 0.03 

- 

- 

- 1.176 f 0.084** 

0.996 f 0.071** 

1.326 f 0.095** 

1.33 f 0.04** 

5 5 5 5 

15-Month interim evaluation 

n 

pg Nilg control lung 

pg Nilg lung 

pg Nillung 

Absolute lung wt (9) 1.37 f 0.07 - 

- 

- 

1.58 f 0.13 

0.188 f 0.013** 

0.166 f 0.012** 

0.257 f 0.017** 

1.49 f 0.04 

0.538 f 0.042** 

0.493 f 0.031** 

0.739 f 0.057** 

2.212 f 0.427** 

1.657 f 0.285** 

3.034 f 0.586** 

1.82 rt 0.08** 

a Mean f standard error; statistical tests were performed on unrounded data. 

** P10.01 

* Significantly different (PlO.05) from the control group by Williams’ or Dunnett’s test (lung weight) or Shirley’s test (lung burden 

parameters) 

n=5 

Results were below 0.282 (7 months) or 0.044 (15 months) (the limits of detection), or below the level of quantitation. 
340 Nickel Sulfate Hexahydrate, NTP TR 454 
341 

TISSUE BURDEN IN MICE 

APPENDIX I 

TABLE I1 Lung Weight and Lung Burden in Mice in the 16-Day Inhalation Study 

TABLE I2 Lung Weight and Lung Burden in Mice in the 13-Week Inhalation Study 

TABLE I3 Lung Weight and Lung Burden in Mice in the 2-Year Inhalation Study 

TABLE I4 Kidney Burden in Mice in the 2-Year Inhalation Study 

of Nickel Sulfate Hexahydrate 

of Nickel Sulfate Hexahydrate 

of Nickel Sulfate Hexahydrate 

of Nickel Sulfate Hexahydrate ..................................... 

345 

344 

343 

342 

..................................... 

..................................... 

..................................... 
342 Nickel Sulfate Hexahydrate, NTP TR 454 

Lung Weight and Lung Burden in Mice in the 16-Day Inhalation Study of Nickel Sulfate Hexahydratea 

TABLE I1 

O mg/m3 3.5 mg/m3 

n 5 5 

Male 

pg Ni/g control lung 

pg Ni/g lung 

pg Ni/lung 

Absolute lung wt (g) 0.144 f 0.006 - b 

- 

- 4.620 f 0.609** 

3.020 f 0.437** 

0.664 f 0.090** 

0.221 f 0.012** 

pg Ni/g control lung 

pg Ni/g lung 

pg Ni/lung 

Absolute lung wt (g) 0.143 f 0.007 

- 

- 

- 4.980 f 1.324** 

3.540 f 0.493** 

0.712 f 0.080** 

0.206 f 0.015** 

b Results were below 0.170 pg Ni (the limit of detection), or below the level of quantitation. 

a Mean f standard error; statistical tests were performed on unrounded data. 

** Significantly different (PSO.01) from the control group by Williams’ test (lung weight) or Shirley’s test (lung burden parameters) 
Tissue Burden in Mice 343 

Lung Weight and Lung Burden in Mice in the 13-Week Inhalation Study of Nickel Sulfate Hexahydratea 

TABLE I2 

O mg/m3 0.12 mg/m3 0.5 mg/m3 2 mg/m3 

Male 

n 

pg Ni/g control lung 

pg Nilg lung 

pg Nillung 

Absolute lung wt (g) 

Female 

n 

pg Ni/g control lung 

pg Nilg lung 

pg Nillung 

Absolute lung wt (9) 

5 

0.183 f 0.008 

- b 

- 

- 

5 

6 

0.166 f 0.011 

- 

- 

- 

6 

0.149 f 0.007 

- 

- 

- 

6 

0.175 f 0.002 - 

- 

- 

5 

0.156 f 0.008 

- 

- 

- 

6 

1.275 rt 0.807 

0.790 f 0.503 

0.234 f 0.148 

0.300 f 0.014** 

6 

0.279 f o.ooa** 

4.008 f o.ao4** 

2.205 f 0.444** 

0.630 f 0.126** 

a Mean f standard error; statistical tests were performed on unrounded data. 

** Significantly different (P50.01) from the control group by Williams’ test (lung weight) or Dunn’s or Shirley’s test (lung burden 

Results were below 0.228 pg Ni (the limit of detection), or below the level of quantitation. 

parameters) 
344 Nickel Sulfate Hexahydrate, NTP TR 454 

TABLE I3 

Lung weight and Lung Burden in Mice in the 2-Year Inhalation Study of Nickel Sulfate Hexahydrate" 

0 mg/m3 0.25 mg/m3 0.5 mg/m' 1 mg/m3 

n 

Male 

pg Ni/g control lung 

pg Ni/g lung 

pg Nillung 

Absolute lung wt (9) 

%Month interim evaluation 

n 

pg Ninung 

Absolute lung wt (g) 

15-Month interim evaluation 

pg Ni/g control lung 

Pg NUg lung 

Female 

n 

pg Ni/g control lung 

pg Nilg lung 

pg Nfimg 

Absolute lung wt (g) 

7-Month interim evaluation 

n 

pg Ni/g control lung 

pg Nilg lung 

pg Nillung 

Absolute lung wt (g) 

15-Month interim evaluation 

5 4 5 5 

0.230 f 0.013 - b 

0.239 f 0.023 - 

- 

- 

0.294 f 0.024 - 

- 

- 

0.251 f 0.028 - 

- 

- 

4 5 3 3 

0.208 f 0.009 - 0.223 f 0.028 - 

- 

- 

0.204 f 0.017 - 

- 

- 

0.251 f 0.006 - 

- 

- 

4 5 5 5 

0.221 f 0.020 - 

- 

- 

0.218 f 0.015 - 

- 

- 

0.257 f 0,009 - 

- 

- 

5 5 5 5 

0.205 f 0.005 - 

- 

- 

0.214 f 0.007 

- 

- 

- 

0.225 f 0.006* - 

- 

- 

0.275 f 0.004** - 

- 

- 

a wan f standard error; statistical tests were performed on unrounded data. 

** PSO.01 

* Significantly different (PSO.05) from the control group by Williams' or Dunnett's test 

Results were below 0.323 pg Ni (7 months) or 0.256 pg Ni (15 months) (the limits of detection), or below the level of quantitation. 
Tissue Burden in Mice 345 

Kidney Burden in Mice in the 2-Year Inhalation Study of Nickel Sulfate Hexahydratea 

TABLE I4 

O mg/m3 0.25 mg/m3 0.5 mg/m3 1 mg/m3 

Male 

n 

7-Month interim evaluation 

pg Nilg kidney 

n 

15-Month interim evaluation 

pg Nilg kidney 

Female 

n 

7-Month interim evaluation 

pg Ni/g kidney 

n 

15-Month interim evaluation 

pg Ni/g kidney 

5 

- 

b 

4 

0.091 f 0.025 

4 

- 

5 

0.128 f 0.034 

A 

- 

5 

0.076 f 0.017 

5 

- 

5 

0.144 f 0.041 

5 5 

- 

3 

- 

3 

0.078 f 0.004 0.113 f 0.015 

5 5 

5 

0.395 f 0.117 - 

4 

0.217 f 0.038 0.125 f 0.030 

a Mean f standard error; statistical tests were performed on unrounded data. 

Results were below 0.305 pg Ni (7 months) or 0.046 pg Ni (15 months) (the limits of detection), or below the level of quantitation. 
346 Nickel Sulfate Hexahydrate, NTP TR 454 
347 

AND ESTROUS CYCLE CHARACTERIZATION 

REPRODUCTIVE TISSUE EVALUATIONS 

APPENDIX J 

TABLE Jl Summary of Reproductive Tissue Evaluations and Estrous Cycle 

of Nickel Sulfate Hexahydrate . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 349 

Characterization for Mice in the 13-Week Inhalation Study 

of Nickel Sulfate Hexahydrate . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 348 

Characterization for Rats in the 13-Week Inhalation Study 

TABLE 52 Summary of Reproductive Tissue Evaluations and Estrous Cycle 
348 Nickel Sulfate Hexahydrate, NTP TR 454 

in the 13-Week Inhalation Study of Nickel Sulfate Hexahydrate 

Summary of Reproductive Tissue Evaluations and Estrous Cycle Characterization for Rats 

TABLE J1 

- 

O mg/m3 0.5 mg/rn3 1 mg/m3 2 mg/m3 

n 10 10 10 9 

Weights (g) 

R. testis 

R. epididymis 

R. cauda 

Necropsy body wt 327 f 5 311 f 5 324 f 5 

0.150 f 0.006 0.139 f 0.008 0.143 f 0.004 

0.485 f 0.016 0.478 f 0.010 0.494 f 0.006 

1.402 f 0.033 1.376 f 0.031 1.443 f 0.042 

310 f 8 

1.352 f 0.035 

0.474 f 0.008 

0.141 f 0.004 

Epididymal spermatozoal measurements 

Concentration ( 106/g cauda epididymal tissue) 

Abnormality (%) 

Motility (X) 95.48 f 0.50 95.05 f 0.53 93.49 f 0.98 92.68 f 1.04 

0.740 f 0.103 0.980 f 0.128 0.760 f 0.088 0.733 f 0.088 

855 f 58 712 f 25 721 f 32 707 f 38 

Female 

n 10 10 10 10 

Necropsy body wt 198 f 5 189 f 3 193 f 3 184 f 4 

~stroustagesb ( % of cycle) 

Estrous cycle length (days) 5.14 f 0.26‘ 4.67 f 0.24d 4.50 f 0.19e 5.25 f 0.25e 

38.6 34.3 

14.3 21.4 

30.0 31.4 

17.1 11.4 

Unclear diagnosis 0.0 1.4 

Metestrus 

Estrus 

Proestrus 

Diestrus 

0.0 

8.6 

32.9 

14.3 

44.3 

2.9 

17.1 

38.6 

17.1 

24.3 

e Estrous cycle was longer than 7 days or was unclear in 2 of 10 animals. 

Estrous cycle was longer than 7 days or was unclear in 1 of 10 animals. 

Estrous cycle was longer than 7 days or was unclear in 3 of 10 animals. 

than control females. 

relative length of time spent in estrous stages. Females in this exposure group spent more time in diestrus and less time in metestrus 

Evidence suggests that females in the 0.5 mg/m3 group differ significantly (P<O.Ol, Wilks’ Criterion) from the control females in the 

or Dunnett’s tests. Statistical tests were performed on unrounded data. 

a Data are presented as mean f standard error. Differences from the control group for all study parameters are not significant by Dunn’s 
Sperm Motility and Vaginal Cytology 349 

in the 13-Week Inhalation Study of Nickel Sulfate Hexahydratea 

Summary of Reproductive Tissue Evaluations and Estrous Cycle Characterization for Mice 

TABLE 52 

O mg/m3 0.5 mg/m3 1 mg/m3 2 mg/m3 

Male 

n 6 

Weights (g) 

R. testis 

R. epididymis 

R. cauda 

Necropsy body wt 

0.113 f 0.002 

0.051 f 0.003 

0.014 f 0.001 

30.3 f 0.6 

Epididymal spermatozoal measurements 

Concentration (106/g cauda epididymal tissue) 

Abnormality (%) 

Motility (%) 

1,310 f 212 

2.53 f 0.20 

94.18 f 0.56 

Female 

n 7 

Necropsy body wt 25.8 f 0.6 

Estrous stages‘ (% of cycle) 

Estrous cycle length (days) 4.29 f 0.36 

0.0 

18.4 

36.7 

16.3 

28.6 

Estrus 

Proestrus 

Diestrus 

Unclear diagnosis 

Metestrus 

10 

0.129 f 0.016 

0.052 f 0.001 

0.013 f 0.001 

31.0 f 0.8 

1.76 f 0.18 

94.23 f 0.27 

1,389 f 74 

4.29 f O.lfld 

26.0 f 0.3 

10 

0.0 

15.7 

42.9 

17.1 

24.3 

10 

0.108 f 0.009 

0.050 f 0.003 

0.012 f 0.001 

31.8 f 0.9 

95.00 f 0.51b 

2.00 f 0.20b 

1,537 f 138b 

4.40 f 0.16 

26.3 f 0.4 

10 

17.1 

40.0 

20.0 

22.9 

0.0 

10 

0.114 f 0.004 

0.050 f 0.003 

0.014 f 0.001 

30.1 f 1.1 

2.34 f 0.19 

95.01 f 0.30 

1.420 f 101 

10 

4.10 f 0.18 

24.7 f 0.5 

17.1 

44.3 

20.0 

17.1 

1.4 

a Data are presented as mean f standard error. Differences from the control group for all study parameters are not significant by Dun” 

Estrous cycle was longer than 7 days or was unclear in 3 of 10 animals. 

estrous stages. 

There is no evidence of any difference between the exposed and control groups in cycle length or in relative length of time spent in 

n=9 

or Dunnett’s tests. Statistical tests were performed on unrounded data. 
350 Nickel Sulfate Hexahydrate, NTP TR 454 
351 

GENERATION OF CHAMBER CONCENTRATIONS 

CHEMICAL CHARACTERIZATION AND 

APPENDIX K 

PROCUREMENT AND CHARACTERIZATION OF NICKEL SULFATE HEXAHYDRATE ............... 352 

FIGURE K7 Daily Mean Filter Concentrations and Standard Deviations 

FIGURE K6 2-Year Nickel Sulfate Hexahydrate Inhalation Suite 

FIGURE K5 13-Week Nickel Sulfate Hexahydrate Inhalation Suite 

FIGURE K4 Schematic of the HlOOO and H2000 Exposure Chambers 

FIGURE K3 Schematic of the Nickel Sulfate Hexahydrate Aerosol Delivery System 

FIGURE K2 Schematic of the Generation System 

FIGURE K1 Infrared Absorption Spectrum of Nickel Sulfate Hexahydrate 

CHAMBER ATMOSPHERE CHARACTERIZATION 

AEROSOL CONCENTRATION MONITORING 

AEROSOL GENERATION AND Exporn SYSTEM 

TABLE K2 Summary of Aerosol Si= Measurements for the 0.12, 0.25, 

TABLE K1 Summary of Aerosol Size Measurements for the Rat and Mouse Chambers 

FIGURE K10 Weekly Mean Filter Concentrations and Standard Deviations 

FIGURE K9 Weekly Mean Filter Concentrations and Standard Deviations 

FIGURE Kt3 Daily Mean Filter Concentrations and Standard Deviations 

.................................. 

361 

360 

359 

358 

357 

356 

354 

353 

352 

366 

365 

364 

363 

362 

....................................... .................................... ................ ................................. ........... .................... 

..................... ....................... 

and 0.5 mg/m3 Rat Chambers in the 2-Year Inhalation Study 

in the 13-Week Inhalation Studies of Nickel Sulfate Hexahydrate 

in the 2-Year Inhalation Study in Mice 

in the 2-Year Inhalation Study in Rats 

in the 13-Week Inhalation Study in Mice 

in the 13-Week Inhalation Study in Rats 

of Nickel Sulfate Hexahydrate 

and 1 mg/m3 Mouse Chambers in the 2-Year Inhalation Study 

of Nickel Sulfate Hexahydrate 

.............................. 

.............................. 

............................... 

............................... 

.............. 

..................................... 367 

TABLE K3 Summary of Aerosol Size Measurements for the 0.25, 0.5, 

..................................... 368 
352 Nickel Sulfate Hexahydrate, NTP TR 454 

GENERATION OF CHAMBER CONCENTRATIONS 

CHEMICAL CHARACTERIZATION AND 

National Institute of Environmental Health Sciences (NIEHS). 

Reports on analyses performed in support of the nickel sulfate hexahydrate studies ire on file at the 

were conducted by the analytical chemistry laboratory, Midwest Research Institute (Kansas City, MO). 

(M062883), which was used during the 16-day, 13-week, and 2-year studies. Identity and purity analyses 

Nickel sulfate hexahydrate was obtained from Aldrich.Chemical Co. (Milwaukee, WI) in one lot 

OF NICKEL SULFATE HEXAHYDRATE 

PROCUREMENT AND CHARACTERIZATION 

sulfate hexahydrate (Figure Kl). No ultraviolet/visible spectra were found in the literature. 

the infrared spectrum was consistent with the literature spectrum (SadtZer Standard Spectra) of nickel 

and ultraviolethisible spectroscopy. All spectra were consistent with those expected for the structure, and 

The chemical, a blue-green crystalline powder, was identified as nickel sulfate hexahydrate by infrared 

manganese (11) chloride solution, and Eriochrome Black T was the indicator. 

ethylenediaminetetraacetate (EDTA) were added. The samples were back-titrated with a standard 

with ammonium/ammonium chloride (NH,/NH,Cl) to pH 9, and ascorbic acid and 

source mass spectrometry, and chelometric titration. For chelometric titration, samples were buffered 

The purity of lot M062883 was determined by elemental analyses, Karl Fischer water analysis, spark 

determined to be greater than 98 % . 

titration indicated a purity of 98.8% f 0.8 % nickel sulfate hexahydrate. The overall purity was 

were cobalt (approximately 1,500 ppm), silicon (470 ppm), and magnesium.( 120 ppm). Chelometric 

spectrometry indicated total impuiities of less than or equal to 2,320 ppm; the major inorganic impurities 

sulfate hexahydrate. Karl Fischer. water analysis indicated 41.3% f 0.7% water. Spark source mass 

Elemental analyses for nickel and hydrogen were in agreement with the theoretical values for nickel 

tightly sealed plastic bags at room temperature. 

To ensure stability, the analytical chemistry laboratory recommended that the bulk chemical be stored in 

Merck Index, 1989). The decomposition temperature of nickel sulfate hexahydrate is given as 675' C. 

information about the physical and chemical properties' of the compound (Ostroff and Sanderson, 1959; 

No accelerated chemical stability studies were performed for nickel sulfate hexahydrate based on literature 

chemical during the studies. 

excursions from specification were sporadic, it was concluded that there was no degradation of the bulk 

sulfur consistently fell within the ranges specified by the analytical chemistry laboratory. Because the 

outside the range recommended by the analytical chemistry laboratory. The values for hydrogen and 

conducted. On two occasions out of the 23 analyses, the values for nickel in the samples fell slightly 

every 4 months during the 2-year studies. Elemental analyses for nickel, hydrogen, and sulfur were 

chemical was performed by Huffman Laboratories, Inc. (Golden, CO) prior to and after all studies and 

The bulk chemical was stored in amber glass bottles at room temperature. Periodic monitoring of the bulk 

(62.1 g/L in distilled and deionized water). The solution was atomized with a Retec nebulizer (In Tox 

Aerosol Generation System. Nickel sulfate hexahydrate aerosol was generated from aqueous solution 

AEROSOL GENERATION AND EXPOSURE SYSTEM 
Chemical Characterization and Generation of Chamber Concentrations 353 

particle charges. 

each generator because of the low aerosol concentrations. A Kr-85 discharger was installed to reduce the 

enclosure. One generator was used with each exposure chamber, and only one nebulizer was used with 

in a walk-in hood. Air was circulated through HEPA filters to remove suspended particles in the 

and manifold for four nebulizers, is shown in Figure K3. The aerosol generation assembly was enclosed 

Products, Albuquerque, NM) (Figure K2). The generation system, which included a solution reservoir 

was filtered and conditioned to achieve a relative humidity of about 40%. 

proper air flow rate. All dilutions took place in a radial dilutor for uniform mixing, and the diluting air 

aerosol doncentration adjustment. The aerosol was then mixed with additional dilution air to achieve the 

The aerosol left the generator at an air flow rate of about 3 ft3/min and passed through a dilutor/dump for 

13-week and 2-year exposure suites are shown in Figures K5 and K6, respectively. 

aerosols that the animals were being exposed to during the 13-week and 2-year studies. Diagrams of the 

entered the chamber. Animal cages were rotated weekly to reduce the variation of concentrations of 

IL) with a flow rate of 60 ft3/min was placed below the aerosol entrance to further mix the aerosol as it 

introduction into the chamber, and a small boxer fan (Model WS 2107FL, Newark Electronics, Chicago, 

concentration and to increase the uniformity of mixing, the aerosol was diluted in a radial dilutor prior to 

chambers, corresponding to 9 to 21 air changes per hour. To reduce the spatial variation of aerosol 

studies, the air flow rate was 14.6 f 2.0 ft3/min in the rat chambers and 8.7 f 1.2 ft3/min in the mouse 

7 f 1 ft3/min in the HlOOO chambers, corresponding to 12 f 2 air changes per hour. In the 2-year 

hour. In the 13-week studies, the air flow rate was 12 f 2 ft3/min in the H2000 chambers and 

used to expose the mice. The air flow rate in the 16-day studies corresponded to 10 to 12 air changes per 

In the 2-year studies, the H2000 chambers were used to expose the rats, and the HlOOO chambers were 

0, 0.12, 0.5, and 2 mg/m3 groups, and the HlOOO chambers were used for the 0.25 and 1 mg/m3 groups. 

used for the 7 and 30 mg/m3 groups. During the 13-week studies, the H2000 chambers were used for the 

the H2000 chambers were used for the 0, 3.5, 15, and 60 mg/m3 groups, and the H 1000 chambers were 

Aberdeen, MD) were used to expose the rats and mice in these studies (Figure K4). In the 16-day studies, 

Stainless steel, multitiered, whole-body exposure chambers (H1000 and H2000, Hazleton Systems, 

and 0.01 f 0.01 mg particle/m3 in the mouse control chamber. 

concentrations of total suspended-particles were 0.02 f 0.01 mg particle/mg3 in the rat control chamber 

suspended particles were detected during the 16-day studies. In the 2-year studies, the mean 

monitored each exposure day of the 16-day and 2-year studies by collecting one 6-hour filter sample. No 

chambers. The background concentrations of total suspended particles in the control chambers were 

the 0.5 and 1 mg/m3 exposure chambers and two 3-hour filter samples from the 0.25 mg/m3 exposure 

study in mice, the aerosol concentrations were monitored by collecting three 2-hour filter samples from 

(3 Wmin flow rate) from the 0.5 mg/m3 chamber samples during each 6-hour exposure day. In the 2-year 

(4.5 L/min flow rate) from the 0.12 and 0.25 mg/m3 exposure chambers and three 2-hour filter samples 

aerosol concentrations in each exposure chamber were monitored by collecting two 3-hour samples 

filter samples (3 Wmin flow rate) for the 0.5, 1 and 2 mg/m3 chambers. In the 2-year study in rats, the 

samples (4.5 Wmin flow rate) for the 0.12 and 0.25 mg/m3 exposure chambers and from three 2-hour 

In the 13-week studies, the aerosol concentrations were determined gravimetrically from two 3-hour 

AEROSOL CONCENTRATION MONITORING 

were collected with 25 mm, Teflon@-coated, fiberglass filters with a pore size of 0.1 pm (Zefluor, 

The flow rate was monitored with calibrated rotameters. To determine aerosol concentration, samples 

a flow rate of 3 to 4.5 Wmin, and all samples in the 2-year studies were collected after a T, of 8 minutes. 

All samples in the 13-week studies were collected after the initial 12 minutes (T,) of aerosol generation at 
354 Nickel Sulfate Hexahydrate, NTP TR 454 

the 2-year studies are presented in Figures K9 and K10. 

fur the 13-week studies are presented in Figures K7 and K8. Weekly mean exposure concentrations for 

deviations of each chamber were calculated for each exposure day. Daily mean exposure concentrations 

calculated by dividing the mass increment (mg) by the volume sampled (m3); the means and standard 

Cerrito, CA) before and after the collection of the samples. The aerosol mass concentrations were 

determined gravimetrically by weighing the filters with an electrobalance (Cahn 29, C&n Instruments, 

Gelman, Ann Arbor, MI). The quantity of nickel sulfate hexahydrate collected on the filters was 

which operates at 2 L/min. 

middle, and end of each filter sampling period. The RAM-S unit has a self-contained sampling system 

exposures. The RAM-S was used to monitor each chamber for at least 2 minutes at the beginning, 

of the aerosol concentrations and to determine the need to adjust the aerosol generation system during 

A continuous aerosol monitor (Model RAM-S, GCA, Co., Bedford, MA) was used to monitor the stability 

sample was at the front of each chamber, and the probe for the RAM-S was at the back of each chamber. 

the middle level of the H2000 and HlOOO chambers above the animal cage. The probe for the filter 

used as an indication of aerosol stability for each exposure day. RAM-S and filter samples were taken at 

each exposure day for each chamber. The coefficient of variation from the RAM-S measurement was 

regression line fitted to the data. The mean and standard deviation of the concentrations were calculated 

readings (volts) were converted to mass concentration (mg/m3) based on the slope and intercept of the 

gravimetrically. Linear regression analysis was performed monthly on these data, and the RAM-S voltage 

taken during a filter-sampling period were plotted versus the aerosol concentration determined 

against the mass concentration obtained gravimetrically. The average of three RAM-S voltage readings 

Aerosol concentration was also quantitated with the RAM-S. The RAM-S voltage output was calibrated 

nickel sulfate hexahydrate. 

prior to exposure and once during the first week of exposure to ensure that the aerosol generated was 

Therrnogravimetric Analysis Unit) and for nickel content by electrothermal atomic absorption spectroscopy 

The aerosol was analyzed for extent of hydration by thermogravimetric analysis (Perkin Elmer TGS-2 

CHAMBER ATMOSPHERE CHARACTERIZATION 

cutoff diameter of each stage, and impactor flow rate. The results are presented in Tables K1 through K3. 

aerodynamic diameter and the geometric standard deviation were calculated from the mass data, effective 

by the difference in stage weight before and after the sample was collected. The mass medium 

was used as impactor substrate. The amount of nickel sulfate hexahydrate on each stage was determined 

6 hours depending on the chamber concentration. Stainless steel shimstock coated with apiezon grease 

multijet cascade impactor operated at a flow rate of 12 L/min. The sampling period ranged from 2 to 

Aerosol size distribution was determined once a month for each exposure chamber with a Lovelace 

mean spatial variations were between 1.95 % and 3.85 % . For mice in the 2-year studies, the mean 

temporal variations of aerosol concentration during exposure were between 2.42% and 3.03 % , and the 

to 17 %, and the spatial variations ranged from 0% to 3 % . For rats in the 2-year studies, the mean 

variation of the three reference samples. In the 13-week studies, the temporal variations ranged from 1 % 

variation of samples collected at different locations, and the temporal variation is the coefficient of 

collected for the other locations. The total variation of aerosol concentrations is the coefficient of 

reference point in each chamber at the start, middle, and end of the procedure. One sample each was 

checked quarterly during the 2-year studies. Three samples were collected with the RAM-S at a specified 

studies without animals in the chambers and with animals during the first week of exposure, and was 

Uniformity of aerosol concentration in the exposure chambers was measured prior to the start of the 
Chemical Characterization and Generation of Chamber Concentrations 355 

and 2.81%. 

temporal variations were between 1.48 % and 2.89 % , and the mean spatial variations were between 1.56 % 

the 2-year studies. 

T,. A T, of 12 minutes was used during the 16-day and 13-week studies, and 8 minutes was used during 

The aerosol rise and fall time (T,) was determined with a RAM-S, and an exposure day was 6 hours plus 

containing material. 

collected on the filter was not solely nickel sulfate hexahydrate, but consisted chiefly of non-nickelchemical analysis of these filter samples by atomic absorption spectroscopy indicated that the aerosol 

(October 1988, and January, April, and October 1989), and were analyzed for nickel content. Results of 

200 pg. The mass of the particles collected during the 2-year studies in mice exceeded 200 pg four times 

particles collected on the filter during the 13-week studies and the 2-year studies in rats never exceeded 

material collected was analyzed for nickel content by atomic absorption spectroscopy. The mass of the 

a flow rate of 3 Wmin. If the weight of the material collected on the filter was greater than 200 pg, the 

and quarterly thereafter during the 2-year studies. The filter samples were collected for about 15 hours at 

evaluated gravimetrically once during the 13-week studies and once during the first 2 weeks of exposure 

Residual concentration of nickel sulfate hexahydrate in the chambers during non-exposure hours was 
01 

eh 

w 

MICROMETERS 

51 

NiSO,-SH,O 

D 

WAVENUMBER (CM’) 

4000 3500 30oo 2500 2OOo 1800 1600 1400 1200 loo0 800 600 400 200 

I I I I I 1 I I I I I I I 

8aICnNe 01 

LO, No. wen3 N&l sdlle.Nxahydnte 

SAMPLE 

Pomwm Drmide pellet 

ORIGIN 

REMARKS 

CELL PATH HIGH LIMIT - SUPPRESSION RESPONSE 

CONCENTRATION KBf REP. SCAN 011 EXPANSION1 SCAN TIME 24 mm EXPANSION 1 

SOLVENT 

- REF. NO. 237~ PRE SAMPLE CHOPPER SLIT PROGRAM 6 REFERENCE LOWUMIT - TIME DRIVE 

OPERATOR 8.H.uINn DATE= SINGLE BEAM - ABS- 

- ABSCISSA ORDINATE PEAKIN ELMER 

in relennce beam 

TNm3r.comb No‘ ’*” - 

- - 
Chemical Characterization and Generation of Chamber Concentrations 357 

COMPRES'SED 

A If3 

AIR (COMPRESSED) 

'N 

Schematic of the Generation System 

FIGURE K2 
358 Nickel Sulfate Hexahydrate, NTP TR 454 

AEROSOL DILUTION/DELIVERY SYSTEM 

OLUTOR 

1 

I u +-- CONOrrONED CLEAN AR 

2 -WAY VALVE 

CHAMBER 

MFCE METER GATE VALVE 

EXHAUST I 

I dh-b CONWTDNED CLEAN AB3 

1 OENERATOR I AEROSOL 

I T 

I 

EXHAUST 

Schematic of the Nickel Sulfate Hexahydrate Aerosol Delivery System 

FIGURE K3 
Chemical Characterization and Generation of Chamber Concentrations 

H2000 

RODENT CAGE UNITEXCRETA CATCH PAN 

EXHAUST 

EXHAUST 

359 

OWTRSUTlON PLATE 

FIGURE K4 

Schematic of the HlOOO and H2000 Exposure Chambers 
360 

r 

Nickel Sulfate Hexahydrate, NTP TR 454 

NiS04 13-WEEK EXPOSURE 

ROOM 260 

i 2.0mglm3 

CH 1 CH3 

E u 

CH4 

CONTROL 

CH5 

DOOR 

'm 0 

WALK-IN HOOD 

AEROSOL GENERATOR 1 

0. I 2mg/m3 

HEPA FILTERS 8 BLOWERS 

I PBENCH TOP 

13-Week Nickel Sulfate Hexahydrate Inhalation Suite 

FIGURE K5 
Chemical Characterization and Generation of Chamber Concentrations 361 

DOOR 

I 

PI 

1 

CH 2. 4. 6, 6. ARE H 1000 CHAMBERS FOR hllCE 

CH 1, 3, 5, 7 ARE H2000 CHALlBEAS FOR RATS 

AIR 

/CON.DITIONER 

-BENCH TOP 

-BALANCE 

2-Year Nickel Sulfate Hexahydrate Inhalation Suite 

FIGURE K6 
362 

2.75 

3*oi T 

Nickel Sulfate Hexahydrate, NTP TR 454 

T 

2.5 

N 

0 

T 

N 2.0 

E 

T 

A 

R 1.75 

T 1.5 

c 2.25 

I 

M 

3 0.5 

F~GURE K7 

in the 13-Week Inhalation Study in Rats 

Daily Mean Filter Concentrations and Standard Deviations 
Chemical Characterization and Generation of Chamber Concentrations 363 

2.5 

N 

0 

T 

N 2.0 

E 

T 

A 

c 2.25 

* 1.75 

1.5 

O.O-II--t----II 

tl 

I I I 

10 20 30 40 50 60 70 

EXPOSURE DAY 

in the 13-Week Inhalation Study in Mice 

Daily Mean Filter Concentrations and Standard Deviations 

FIGURE K8 
364 Nickel Sulfate Hexahydrate, NTP TR 454 

0.55 

0.50 

0 

T 

E 

N 

c 0.45 

0.40 

M 

N 

U 

0.25 

.. 

0.10 

3 0.15 

0.05 I 

1 1 1 I I I 1 I 

10 20 30 40 50 6'0 70 BO 90 Id0 110 

WEEK ON STUDY 

FIGURE K9 

in the 2-Year Inhalation Study in Rats 

Weekly Mean Filter Concentrations and Standard Deviations 
Chemical Characterization and Generation of Chamber Concentrations 365 

1.1 

N 

C 

0 1.0 

0.9 

N I 

0.8t 

R 

I 

A T 0.71 

0.5 

I w-r -- 

G 

0.3+ T 

-&la--- 

I 

I I 1 I I I I 1 I 1 I I 

10 2'0 30 40 50 60 70 80 90 lb0 110 

WEEK ON STUDY 

in the 2-Year Inhalation Study in Mice 

Weekly Mean Filter Concentrations and Standard Deviations 

FIGURE K10 
Nickel Sulfate Hexahydrate, NTP TR 454 

in the 13-Week Inhalation Studies of Nickel Sulfate Hexahydrate 

Summary of Aerosol Size Measurements for the Rat and Mouse Chambers 

TABLE K1 

(mg/m3) 

Concentration 

Target 

Diameter (crm) 

Aerodynamic 

Mass Median 

Deviation 

Standard 

Geometric 

0.12 

0.25 

2.0 

1 .o 

0.5 

2.01 

1.81 

3.08 

2.11 

2.31 2.1 

2.0 

2.2 

2.9 

2.7 
Chemical Characterization and Generation of Chamber Concentrations 367 

in the 2-Year Inhalation Study of Nickel Sulfate Hexahydrate 

Summary of Aerosol Size Measurements for the 0.12, 0.25, and 0.5 mg/m3 Rat Chambers 

TABLE K2 

0.12 malm3 

Diameter (pm) Deviation Diameter (pm) Deviation Diameter (pm) Deviation 

Aerodynamic Standard Aerodynamic Standard Aerodynamic Standard 

Mass Median Geometric Mass Median Geometric Mass Median Geometric 

0.25 mg/m3 0.5 mg/m3 

Date 

June 1990 

May 1990 

April 1990 

March 1990 

February 1990 

January 1990 

December 1989 

November 1989 

October 1989 

September 1989 

August 1989 

July 1989 

June 1989 

May 1989 

April 1989 

March 1989 

February 1989 

January 1989 

December 1988 

November 1988 

October 1988 

September 1988 

August 1988 

July 1988 

deviation 

Mean f standard 

2.34 

2.18 

2.25 

2.41 

3 .OO 

2.05 

2.58 

2.20 

2.86 

1.91 

2.25 

2.44 

2.45 

2.64 

1.98 

2.26 

2.06 

2.88 

3.17 

2.74 

2.70 

3.08 

2.22 

3.14 

2.34 

1.65 

2.38 

2.61 

2.05 

2.52 

2.41 

2.54 

2.16 

2.43 

2.32 

2.32 

2.43 

2.36 

2.41 

2.15 

2.31 

2.88 

2.64 

2.86 

2.75 

2.07 

2.32 

2.29 

2.12 

2.26 

2.19 

2.07 

2.22 

2.49 

2.30 

2.38 

2.54 

2.66 

2.20 

1.92 

1.97 

1.93 

2.30 

2.59 

2.28 

2.24 

2.90 

2.10 

1.82 

1.95 

2.11 

2.41 

2.07 

2.27 

2.24 

2.19 

2.03 

2.22 

2.12 

2.08 

2.13 

1.95 

2.08 

2.20 

1.79 

2.31 

1.93 

1.81 

2.16 

2.37 

2.54 

2.55 

2.33 

2.81 

2.12 

2.78 

2.50 f 0.38 2.38 f 0.27 2.24 f 0.26 2.21 f 0.26 

2.21 

2.44 

2.58 

2.32 

2.23 

2.46 

2.09 

2.47 

2.39 

2.15 

2.23 

2.15 

2.12 

2.31 

2.15 

2.17 

2.09 

2.15 

2.34 

1.85 

2.26 

2.25 

2.36 

2.27 

1.90 

1.71 

2.05 

2.03 

1.92 

2.26 

2.21 

1.91 

1.94 

2.08 

2.06 

2.27 

2.17 

2.01 

1.90 

2.04 

2.01 

2.03 

2.18 

2.43 

2.28 

2.33 

2.09 

2.21 

2.25 f 0.16 2.08 f 0.17 
368 Nickel Sulfate Hexahydrate, NTP TR 454 

in the 2-Year Inhalation Study of Nickel Sulfate Hexahydrate 

Summary of Aerosol Size Measurements for the 0.25, 0.5, and 1 mg/m’ Mouse Chambers 

TABLE K3 

0.25 mn/m’ 

Diameter (pm) Deviation Diameter (pm) Deviation Diameter (pm) Deviation 

Aerodynamic Standard Aerodynamic Standard Aerodynamic Standard 

Mass Median Geometric Mass Median Geometric Mass Median Geometric 

0.5 mg/m3 1 mg/m3 

Date 

May 1990 

April 1990 

March 1990 

February 1990 

January 1990 

December 1989 

November 1989 

October 1989 

September 1989 

August 1989 

July 1989 

June 1989 

May 1989 

April 1989 

March 1989 

February 1989 

January 1989 

December 1988 

November 1988 

October 1988 

September 1988 

August 1988 

July 1988 

June 1988 

deviation 

Mean f standard 

2.04 

2.49 

2.70 

2.31 

2.91 

2.21 

2.55 

2.47 

2.16 

2.08 

2.27 

2.39 

2.22 

2.31 

2.24 

2.38 

2.23 

2.71 

2.36 

2.09 

2.13 

2.23 

2.33 

2.46 

2.28 

2.20 

2.22 

2.29 

2.33 

2.29 

1.83 

2.01 

2.18 

2.04 

2.33 

2.32 

2.37 

2.05 

2.19 

2.16 

2.26 

2.02 

2.32 

2.65 

2.38 

2.46 

2.36 

2.25 

2.13 

2.41 

2.22 

2.41 

2.42 

2.22 

2.57 

2.68 

2.18 

2.30 

1.87 

2.41 

2.29 

2.09 

2.38 

2.11 

2.06 

2.23 

2.17 

2.18 

2.31 

2.10 

2.22 

2.42 

1.93 

1.94 

2.02 

2.35 

2.05 

2.13 

1.91 

1.83 

2.07 

2.09 

2.23 

1.89 

2.15 

2.00 

1.93 

2.08 

1.99 

2.19 

2.33 

2.06 

2.11 

2.14 

2.12 

2.19 

2.34 f 0.21 2.24 f 0.17 2.27 f 0.18 2.07 f 0.13 

2.33 

2.44 

2.64 

2.68 

2.67 

2.55 

2.69 

2.16 

2.78 

2.40 

2.15 

2.67 

2.90 

2.54 

2.46 

2.41 

2.36 

2.73 

2.61 

2.55 

2.51 

2.54 

2.69 

2.11 

1.90 

1.95 

1.87 

1.99 

2.11 

1.91 

1.95 

2.20 

2.09 

2.05 

2.18 

1.95 

1.65 

1.96 

2.05 

1.93 

2.11 

1.78 

2.17 

2.18 

2.01 

2.06 

2.32 

2.18 

2.53 f 0.20 2.02 f 0.15 
369 

AND CONTAMINANT LEVELS 

INGREDIENTS, NUTRIENT COMPOSITION, 

APPENDIX L 

IN NIH-07 RAT AND MOUSE RATION 

TABLE L1 Ingredients of NM-07 Rat and Mouse Ration 

TABLE L2 Vitamins and Minerals in NIH-07 Rat and Mouse Ration 

TABLE L3 Nutrient Composition of NIH-07 Rat and Mouse Ration 

TABLE L4 Contaminant Levels in NIH-07 Rat and Mouse Ration 

........................... 

372 

371 

370 

370 

................... 

.................... 

..................... 
370 Nickel Sulfate Hexahydrate, NTP TR 454 

Ingredients of NIH-07 Rat and Mouse Rationa 

TABLE L1 

Ingredientsb Percent by Weight 

Premixes (vitamin and mineral) 

Salt 

Ground limestone 

Dicalcium phosphate 

Dry molasses 

Dried brewer’s yeast 

Soy oil 

Corn gluten meal (60% protein) 

Alfalfa meal (dehydrated, 17% protein) 

Dried skim milk 

Wheat middlings 

Fish meal (60% protein) 

Soybean meal (49% protein) 

Ground hard winter wheat 

Ground #2 yellow shelled corn 

10.00 

10.00 

12.00 

23.00 

24.50 

0.25 

0.50 

0.50 

I .25 

1.50 

2 .oo 

2.50 

3 .oo 

4.00 

5 .OO 

a NCI, 1976; NIH, 1978 

Ingredients were ground to pass through a U.S. Standard Screen No. 16 before being mixed. 

Vitamins and Minerals in NIH-07 Rat and Mouse Rationa 

TABLE L2 

Amount Source 

Vitamins 

A 

K3 

D3 

Thiamine 

Riboflavin 

d-Pantothenic acid 

Niacin 

Folic acid 

Choline 

d-a-Tocopheryl acetate 

Biotin 

Pyridoxine 

B12. 

Cobalt 

Iodine 

Copper 

Zinc 

Manganese 

Iron 

Minerals 

10.0 g 

3.4 g 

18.0 g 

30.0 g 

2.2 g 

560.0 g 

20,OOO TU 

2.8 g 

4,600,OOO IU 

5,500,000 IU 

140.0 mg 

1.7 g 

4,000 pg 

Menadione 

D-activated animal sterol 

Stabilized vitamin A palmitate or acetate 

Choline chloride 

d-Calcium pantothenate 

Thiamine mononitrate 

d-Biotin 

Pyridoxine hydrochloride 

120.0 g 

Cobalt carbonate 

Calcium iodate 

Copper sulfate 

Zinc oxide 

Manganous oxide 

Iron sulfate 

0.4 g 

1.4 g 

4.0 g 

16.0 g 

60.0 g 

a Per ton (2,000 Ib) of finished product 
Feed Analyses 

TABLE L3 

Nutrient Composition of NIH-07 Rat and Mouse Ration 

371 

Nutrient Deviation 

Mean f Standard 

Range Number of Samples 

Ash (% by weight) 

Crude fiber (% by weight) 

CNde fat (% by weight) 

Protein (% by weight) 

Amino Acids (W of total diet) 

Valine 

Tyrosine 

Tryptophan 

Threonine 

Phenylalanine 

Methionine 

Lysine 

Leucine 

Isoleucine 

Histidine 

Glycine 

Cystine 

Arginine 

Essential Fatty Acids (70 of total diet) 

Linolenic 

Linoleic 

Vitamins 

Choline (ppm) 

Vitamin B,, (ppb) 

Biotin (ppm) 

Folic acid (ppm) 

Pyridoxine (ppm) 

Pantothenic acid (ppm) 

Niacin (ppm) 

Riboflavin (ppm) 

Thiamine (ppm) 

a-Tocopherol (ppm) 

Vitamin D (IU/kg) 

Vitamin A (IUlkg) 

Minerals 

Zinc (ppm) 

Manganese (ppm) 

Iron (ppm) 

Sulfur (%) 

Magnesium (%) 

Sodium (%) 

Chloride (%) 

Potassium (%) 

Phosphorus (%) 

Calcium (%) 

Cobalt (ppm) 

Chromium (ppm) 

Iodine (ppm) 

Copper (ppm) 

6.57 f 0.30 

3.67 f 0.41 

5.34 f 0.30 

23.10 f 0.74 

0.917 f 0.034 

0.580 f 0.024 

1.160 f 0.050 

0.306 f 0.075 

1.287 f 0.084 

1.089 f 0.057 

0.677 f 0.105 

0.223 f 0.160 

0.896 f 0.055 

0.994 f 0.125 

0.437 f 0.115 

1.273 * 0.051 

1.972 f 0.052 

0.277 f 0.036 

2.389 f 0.233 

19.00 f 2.26 

36.92 f 9.32 

4,450 f 1,382 

6,665 f 1,833 

3.068 f 314 

40.14 f 20.04 

0.267 f 0.049 

2.51 f 0.64 

9.25 f 2.62 

30.30 f 3.60 

100.95 f 25.92 

7.92 f 0.93 

0.274 f 0.063 

0.168 f 0.008 

0.315 f 0.034 

0.526 f 0.092 

0.887 f 0.067 

0.95 f 0.03 

1.23 f 0.11 

11 SO f 2.40 

58.14 f 9.91 

92.24 f 5.35 

356.2 f 90.0 

0.797 f 0.23 

1.71 f 0.45 

3.70 f 1.14 

6.11 - 7.30 

2.80 - 4.30 

4.60 - 5.90 

21.80 - 24.20 

0.962 - 1.170 

0.564 - 0.794 

0.107 - 0.671 

0.824 - 0.985 

0.665 - 1.110 

0.306 - 0.699 

1.200 - 1.370 

1.850 - 2.040 

0.867 - 0.965 

0.531 - 0.608 

1.060 - 1.220 

0.181 - 0.400 

1.100 - 1.390 

0.210 - 0.320 

1.830 - 2.570 

2,400 - 3,430 

10.6 - 65.0 

0.19 - 0.35 

1.80 - 3.70 

5.60 - 14.0 

23.0 - 34.6 

65.0 - 150.0 

6.10 - 9.00 

16.0 - 28.0 

22.5 - 48.9 

3,000 - 6,300 

4,180 - 12,140 

0.151 - 0.180 

0.258 - 0.370 

0.380 - 0.635 

0.772 - 0.971 

0.89 - 1.00 

1.06 - 1.54 

46.10 - 81.60 

81.70 - 99.40 

255.0 - 523.0 

0.208 - 0.420 

0.49 - 1.15 

0.85 - 2.09 

1.52 - 5.83 

8.09 - 15.39 

27 

27 

27 

27 

10 

10 

10 

10 

10 

10 

10 

10 

10 

10 

10 

10 

10 

9 

9 

10 

10 

10 

10 

10 

9 

10 

27 

9 

4 

27 

9 

6 

9 

to 

10 

10 

10 

10 

10 

10 

10 

8 

8 

27 

27 
372 Nickel Sulfate Hexahydrate, NTP TR 454 

TABLE LA 

Contaminant Levels in NIH-07 Rat and Mouse Rationa 

Deviationb 

Mean f Standard 

Range Number of Samples 

Cadmium (ppm) 

Arsenic (ppm) 

Contaminants 

BHA (PPmle 

Nitrite nitrogen (ppm)d 

Nitrate nitrogen (ppm)d 

Aflatoxins (ppb)' 

Selenium (ppm) 

Mercury (ppm) 

Lead (PPm 

N-Nitrosopyrrolidine (ppb) 

N-Nitrosodimethylamine (p b)' 

Total nitrosoamines (ppb)' 

Salmonella (MPNlg) 

Escherichia coli (MPN/g) 

Coliform (MPNIg) 

Aerobic plate count (CFUIg) 

BHT (ppmle 

P 

Pesticides (ppm) 

6-BHC 

T-BHC 

j3-BHC 

CX-BHC 

Endosulfan sulfate 

Endosulfan I1 

Endosulfan I 

Malathion 

Ethyl parathion 

Methyl parathion 

Diarinon 

Trithion 

Ethion 

Ronnel 

Estimated PCBs 

Toxaphene 

Chlordane 

Telodrin 

Endrin 

Dieldrin 

Methoxychlor 

Mirex 

HCB 

DDT 

DDD 

DDE 

Heptachlor epoxide 

Aldrin 

Heptachlor 

1.30 f 0.60 

1.44 f 0.63 

0.23 f 0.19 

16.60 f 3.93 

<5.0 

0.41 f 0.24 

0.04 f 0.02 

0.25 f 0.17 

0.08 f 0.02 

0.24 f 0.18 

42,755 f 23,943 

45 f 210 

<3 

2.00 f 1.14 

5.83 f 2.59 

7.83 f 3.00 

Negative 

< 0.02 

<0.02 

<0.1 

<0.05 

<0.02 

<0.01 

<0.2 

<0.1 

<0.05 

<0.01 

<0.01 

<0.01 

<0.05 

<0.01 

<0.01 

<0.01 

<0.01 

<0.01 

<0.01 

<0.01 

<0.01 

<0.01 

<0.01 

<0.02 

<0.01 

<0.03 

<0.01 

<0.01 

0.23 f 0.22 

0.16 - 1.21 

0.02 - 0.11 

0.10 - 1.00 

0.05 - 0.10 

0.05 - 0.60 

6,700 - 120,OOO 

0.10 - 3.00 

0.10 - 3.00 

0.01 - 0.07 

8.60 - 24.0 

3 - 1,100 

0.90 - 5.20 

2.60 - 13.00 

3.60 - 16.50 

0.05 - 1.00 

27 

27 

27 

27 

27 

27 

27 

27 

27 

27 

27 

26 

27 

27 

27 

27 

27 

27 

27 

27 

27 

27 

27 

27 

27 

27 

27 

27 

27 

27 

27 

27 

27 

27 

27 

27 

27 

27 

27 

27 

27 

27 

27 

27 

27 

27 

a CFU = colony forming units, MPN = most probable number, BHC = hexachlorocyclohexane or benzene hexachloride 

Sources of contamination: alfalfa, grains, and fish meal. 

No aflatoxin measurement was recorded for the lot milled 2 October 1989. 

For values less than the limit of detection, the detection limit is given as the mean. 

e Sources of contamination: soy oil and fish meal. ' All values were corrected for percent recovexy. 
373 

SENTINEL ANIMAL PROGRAM 

APPENDIX M 

METHODS. .......................................................... 374 

in the 13-Week and 2-Year Inhalation Studies of Nickel Sulfate Hexahydrate . . . . . . 376 

TABLE Ml Murine Virus Antibody Determinations for Rats and Mice 
374 Nickel Sulfate Hexahydrate, NTP TR 454 

METHODS 

SENTINEL ANIMAL PROGRAM 

source and weanling groups as the animals used for the studies of chemical compounds. 

are subject to identical environmental conditions. The sentinel animals come from the same production 

serology on sera from extra (sentinel) animals in the study rooms. These animals and the study animals 

evaluation of chemical compounds. Under this program, the disease state of the rodents is monitored via 

Animal Program is part of the periodic monitoring of animal health that occurs during the toxicologic 

optimally clean facilities to eliminate potential pathogens that may affect study results. The Sentinel 

Rodents used in the Carcinogenesis Program of the National Toxicology Program are produced in 

performed are tabulated below; the times at which blood was collected during the studies are also listed. 

determination of antibody titers. The laboratory serology methods and viral agents for which testing was 

were processed appropriately and sent to Microbiological Associates, Inc. (Bethesda, MD) for 

studies. Blood from each animal was collected, allowed to clot and the serum separated. The samples 

Serum samples were collected from randomly selected rats and mice during the 13-week and 2-year 

Method of Analysis 

ELISA 

13-Week Study 

RATS 

RCV/SDA 

PVM (pneumonia virus of mice) 

Mycoplasma pulmonis 

Mycoplasma arthritidis 

CARE3 (cilia-associated respiratory bacillus) 

Sendai 

(rat coronavirus/sialodacryoadenitis virus) 

KRV (Kilham rat virus) 

H-1 (Toolan’s H-1 virus) 

Hemagglutination Inhibition 

Immunofluorescence Assay 

RCV (rat coronavirus) 

ELISA 

2-Year Study 

Sendai 

RCV/SDA 

PVM 

M. pulmonis 

M. arthritidis 

MHV (mouse hepatitis virus) 

Mouse adenoma virus 

MVM (minute virus of mice) 

LCM (lymphocytic choriomeningitis virus) 

GDVII (mouse encephalomyelitis virus) 

Ectromelia virus 

Time of Analysis 

Quarantine, study initiation, and study termination 

Quarantine and study initiation 

Quarantine and study initiation 

Study termination 

Quarantine, study initiation, and study termination 

Quarantine, study initiation, and study termination 

Quarantine, study initiation, and study termination 

Quarantine, study initiation, and study termination 

Study initiation 

Study initiation, 6, 15, and 24 months 

Study initiation, 6, 15, and 24 months 

Study initiation, 6, 15, and 24 months 

24 months 

24 months 

Study initiation 

Study initiation 

Study initiation 

Study initiation 

Study initiation 

Study initiation 
Sentinel Animal Program 375 

Hemagglutination Inhibition 

%Year Study (continued) 

RATS (continued) 

Polyoma virus 

KRV 

K (papovavirus) 

H- 1 

Immunofluorescence Assay 

Reovirus 3 

EDIM (epizootic diarrhea of infant mice) 

Complement Fixation 

13-Week Study 

MICE 

LCM 

ELISA 

Sendai 

PVM 

M. pulmonis 

M. arthritidis 

MHV 

Mouse adenoma virus 

MVM 

GDVII 

Ectromelia virus 

CARB 

Hemagglutination Inhibition 

K 

Polyoma virus 

Immunofluorescence Assay 

Reovirus 3 

EDIM 

ELISA 

2-Year Study 

Sendai 

Reovirus 3 

PVM 

M. pulmonis 

M. arthritidis 

MHV 

Mouse adenoma virus 

MVM 

LCM 

GDVII 

EDIM 

Ectromelia virus 

Study initiation 

Study initiation, 6, 15, and 24 months 

Study initiation 

Study initiation, 6, 15, and 24 months 

Study initiation 

Study initiation 

Quarantine and study termination 

Quarantine and study termination 

Quarantine and study termination 

Quarantine 

Quarantine 

Quarantine and study termination 

Quarantine and study termination 

Quarantine and study termination 

Quarantine and study termination 

Quarantine and study termination 

Study termination 

Quarantine and study termination 

Quarantine and study termination 

Quarantine and study termination 

Quarantine and study termination 

Study initiation, 7, 15, and 24 months 

7, 15, and 24 months 

Study initiation, 7, 15, and 24 months 

24 months 

24 months 

Study initiation, 7, 15, and 24 months 

Study initiation, 7, 15, and 24 months 

Study initiation, 7, and 15 months 

Study initiation, 15, and 24 months 

Study initiation, 7, 15, and 24 months 

24 months 

Study initiation, 7, 15, and 24 months 
376 Nickel Sulfate Hexahydrate, NTP TR 454 

Hemagglutination Inhibition 

%Year Study (continued) 

MICE (continued) 

Polyoma virus 

K 

Study initiation, 7, 15, and 24 months 

Study initiation, 7, 15, and 24 months 

Immunofluorescence Assay 

Reovirus 3 

MVM 

LCM 

EDIM 

Study initiation, 7, and 24 months 

24 months 

7 months 

Study initiation, 7, and 15 months 

Results of serology tests are presented in Table MI. 

of Nickel Sulfate Hexahydrate 

Murine Virus Antibody Determinations for Rats and Mice in the 13-Week and 2-Year Inhalation 

TABLE M1 

Studies 

Interval 

in Sentinel Animals 

Incidence of Antibody 

Reaction for 

Positive Serologic 

13-Week Studies 

Rats 

Study termination 

Week 1 

Quarantine screening 

Mice 

Study termination 

Quarantine screening 

2-Year Studies 

Rats 

24 Months 

15 Months 

6 Months 

Quarantine screening 

Mice 

24 Months 

15 Months 

7 Months 

Quarantine screening 

10110 

10110 

1/10 

0110 

0110 

0110 

6/16 

0116 

0116 

0110 

1116 

0116 

4/16 

0110 

Sendai 

RCVlSDA 

RCVISDA 

None positive 

None positive 

None positive 

M. arthritidisa 

None positive 

None positive 

None positive 

Reovirus 3 

None positive 

Reovirus 3 

None positive 

a Further evaluation of samples positive for M. arthrifih by immunoblot and Western blot procedures indicated that the positive titers 

M. arthrifidis-positive titers were considered to be false positive. 

there were no clinical signs or histopathologic changes of". oflhrifidis infection in rats with positive titers. Accordingly, 

may be due to cross reaction with antibodies of nonpath4genic Mycoplasma or other agents. Only sporadic samples were positive and 
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