1978 

National Cancer Institute 

CARCINOGENESIS 

Technical Report Series 

No. 76 

BIOASSAY OF 

TRIS (2,3-DIBROMOPROPYL) PHOSPHATE 

FOR POSSIBLE CARCINOGENICITY 

CAS No. 126-72-7 

NCI-CG-TR-76 

U.S. DEPARTMENT OF HEALTH, EDUCATION, AND WELFARE 

Public Health Service 

National Institutes of Health 

BIOASSAY OF
 

TRIS (2,3-DIBROMOPROPYL) PHOSPHATE
 

FOR POSSIBLE CARCINOGEN1CITY
 

Carcinogenesis Testing Program
 

Division of Cancer Cause and Prevention
 

National Cancer Institute
 

National Institutes of Health
 

Bethesda, Maryland 20014
 

U.S. DEPARTMENT OF HEALTH, EDUCATION, AND WELFARE
 

Public Health Service
 

National Institutes of Health
 

DHEW Publication No. (NIH) 78-1326
 

REPORT ON THE BIOASSAY OF TRIS (2,3-DIBROMOPROPYL) PHOSPHATE
 

FOR POSSIBLE CARCINOGENICITY
 

CARCINOGENESIS TESTING PROGRAM
 

DIVISION OF CANCER CAUSE AND PREVENTION
 

NATIONAL CANCER INSTITUTE, NATIONAL INSTITUTES OF HEALTH
 

FOREWORD: This report presents the results of the bioassay of
 

tris (2,3-dibromopropyl) phosphate conducted for the Carcinogenesis
 

Testing Program, Division of Cancer Cause and Prevention, National
 

Cancer Institute (NCI), National Institutes of Health, Bethesda,
 

Maryland. This is one of a series of experiments designed to determine whether selected chemicals have the capacity to produce cancer
 

in animals. Negative results, in which the test animals do not have
 

a significantly greater incidence of cancer than control animals, do
 

not necessarily mean the test chemical is not a carcinogen because
 

the experiments are conducted under a limited set of circumstances.
 

Positive results demonstrate that the test chemical is carcinogenic
 

for animals under the conditions of the test and indicate a potential
 

risk to man. The actual determination of the risk to man from animal
 

carcinogens requires a wider analysis.
 

CONTRIBUTORS: This bioassay of tris (2,3-dibromopropyl) phosphate
 

was conducted by Mason Research Institute, Worcester, Massachusetts,
 

initially under direct contract to the NCI and currently under a subcontract to Tracor Jitco, Inc., prime contractor for the NCI Carcinogenesis Testing Program.
 

The experimental design was determined by the NCI Project Officers, Dr. J. H. Weisburger (1,2) and Dr. E. K. Weisburger (1). The
 

principal investigators for the contract were Dr. E. Smith (3) and
 

Dr. A. Handler (3). Animal treatment and observation were supervised
 

by Mr. G. Wade (3) and Ms. E. Zepp (3). Chemical analysis was performed by Midwest Research Institute (4) and the analytical results
 

were reviewed by Dr. N. Zimmerman (5).
 

Histopathologic examinations were performed by Dr. A. S. Krishna
 

(3) and Dr. A. Russfield (3) at the Mason Research Institute, and the
 

diagnoses included in this report represent the interpretation of
 

these pathologists. Histopathology findings and reports were reviewed by Dr. R. L. Schueler (6).
 

Compilation of individual animal survival, pathology, and summary
 

tables was performed by EG&G Mason Research Institute (7); the statistical analysis was performed by Mr. W. W. Belew (5) and Dr. J. R.
 

Joiner (6), using methods selected for the Bioassay Program by Dr. J.
 

J. Gart (8).
 

iii
 
This report was prepared at METREK, a Division of The MITRE Corporation (5) under the direction of the NCI. Those responsible for
 

this report at METREK are the project coordinator, Dr. L. W. Thomas
 

(5), the task leader, Dr. M. R. Kornreich (5), the senior biologist,
 

Ms. P. Walker (5) and the technical editor, Ms. P. A. Miller (5).
 

The final report was reviewed by members of the participating organizations.
 

The statistical analysis was reviewed by members of the Mathematical Statistics and Applied Mathematics Section of the NCI: Dr.
 

J. J. Gart (8), Mr. J. Nam (8), Dr. H. M. Pettigrew (8), and Dr. R.
 

E. Tarone (8).
 

The following other scientists at the National Cancer Institute
 

were responsible for evaluating the bioassay experiment, interpreting
 

the results, and reporting the findings: Dr. K. C. Chu (1), Dr. C.
 

Cueto, Jr. (1), Dr. J. F. Douglas (1), Dr. D. G. Goodman (1), Dr. R.
 

A. Griesemer (1), Dr. H. A. Milman (1), Dr. T. W. Orme (1), Dr. R. A.
 

Squire (1,9), Dr. J. M. Ward (1), and Dr. C. E. Whitmire (1).
 

1.	 Carcinogenesis Testing Program, Division of Cancer Cause and
 

Prevention, National Cancer Institute, National Institutes of
 

Health, Bethesda, Maryland.
 

2.	 Now with the Naylor Dana Institute for Disease Prevention, American Health Foundation, Hammon House Road, Valhalla, New York.
 

3.	 Mason Research Institute, 57 Union Street, Worcester, Massachusetts .
 

4.	 Midwest Research Institute, 425 Volker Boulevard, Kansas City,
 

Missouri.
 

5.	 Th MITR e E Corporation, METREK Division, 1820 Dolley Madison
 

Boulevard, McLean, Virginia.
 

6.	 Tracer Jitco, Inc., 1776 East Jefferson Street, Rockville,
 

Maryland.
 

7.	 EG&G Mason Research Institute, 1530 East Jefferson Street,
 

Rockville, Maryland.
 

8.	 Mathematical Statistics and Applied Mathematics Section, Biometry
 

Branch, Field Studies and Statistics Program, Division of Cancer
 

Cause and Prevention, National Cancer Institute, National Institutes of Health, Bethesda, Maryland.
 

iv
 
9.	 No wit w h the Division of Comparative Medicine, Johns Hopkins
 

University, School of Medicine, Traylor Building, Baltimore,
 

Maryland.
 

v
 

SUMMARY 

A bioassay of technical-grade tris (2,3-dibromopropyl) phosphate
 

(TBP) for possible carcinogenicity was conducted using Fischer 344
 

rats and B6C3F1 mice. TBP was administered in the feed, at either of
 

two concentrations, to groups of 55 male and 55 female rats, and 50
 

male and 50 female mice. The high and low dietary concentrations of
 

TBP administered were, respectively, 100 and 50 ppm for the male and
 

female rats, and 1000 and 500 ppm for the male and female mice. After
 

a 103-week dosing period, observation of the rats and mice continued
 

for 1 or 2 additional weeks. For each species, 55 animals of each
 

sex were placed on test as controls. No TBP was added to their diet.
 

In both species, adequate numbers of animals in all groups survived sufficiently long to be at risk from late-developing tumors.
 

Kidney tubular-cell adenomas were observed at incidences which
 

were significant for dosed rats of both sexes by all statistical tests
 

applied. For m?le rats there was a significant positive association
 

between the incidence of kidney tubular-cell adenocarcinomas and dietary concentration of TBP. Other neoplastic lesions appearing in the
 

treated rats were not statistically significant when compared with the
 

control groups.
 

Among mice, a number of malignant and benign tumors were associated with TBP administration. These tumors included renal tubular-


cell carcinoma and adenoma; squamous-cell papilloma and carcinoma of
 

the forestomach; hepatocellular carcinoma and adenoma; and bronchiolar/
 

alveol .r adenoma and carcinoma.
 

Renal tubular-cell carcinomas were observed at a statistically
 

significant incidence in male mice but none were observed in females.
 

Tubular-cell adenomas were observed in treated mice of both sexes,
 

but not in their respective controls. The incidence of tubular-cell
 

adenomas was significant in male mice but not in females.
 

Squamous-cell carcinomas were observed in forestomachs of mice
 

of both sexes but not in their respective controls. The incidence was
 

significant in females but not in males. The incidences of squamouscell papillomas of the forestomach were significant in mice of both
 

sexes.
 

Incidences of hepatocellular carcinoma and hepatocellular adenoma
 

were each significant in female mice. Tumor incidence among male mice
 

was not significant for hepatocellular carcinomas or hepatocellular
 

adenomas.
 

vii 
The proportion of mice of each sex having bronchiolar/alveolar
 

adenoma or carcinoma or both had a significant positive dose-related
 

trend. The incidence of bronchiolar/alveolar carcinomas exhibited a
 

significant positive dose-related trend for males, but not for females .
 

It is concluded that under the conditions of this study orally
 

administered TBP was carcinogenic to B6C3F1 mice, causing increased
 

incidences of tumors in livers, lungs, and stomachs of female mice
 

and in kidneys, lungs, and stomachs of male mice. TBP was also carcinogenic in Fischer 344 rats, causing an increased incidence of kidney tumors in both sexes.
 

viii
 
TABLE OF CONTENTS
 

Page
 

I. INTRODUCTION 1
 

II. MATERIALS AND METHODS 4
 

A. Chemicals 4
 

B. Dietary Preparation 4
 

C. Animals 5
 

D. Animal Maintenance 5
 

E. Selection of Initial Concentrations 7
 

F. Experimental Design 8
 

G. Clinical and Histopathologic Examinations 9
 

H. Data Recording and Statistical Analyses 13
 

III. CHRONIC TESTING RESULTS: RATS 18
 

A. Body Weights and Clinical Observations 18
 

B. Survival 18
 

C. Pathology 21
 

D. Statistical Analyses of Results 23
 

IV. CHRONIC TESTING RESULTS: MICE 35
 

A. Body Weights and Clinical Observations 35
 

B. Survival 35
 

C. Pathology 38
 

D. Statistical Analyses of Results 43
 

V. DISCUSSION 56
 

VI. BIBLIOGRAPHY 61
 

APPENDIX A SUMMARY OF THE INCIDENCE OF NEOPLASMS IN
 

RATS TREATED WITH TBP A-l
 

APPENDIX B SUMMARY OF THE INCIDENCE OF NEOPLASMS IN
 

MICE TREATED WITH TBP B-l
 

APPENDIX C SUMMARY OF THE INCIDENCE OF NONNEOPLASTIC
 

LESIONS IN RATS TREATED WITH TBP C-l
 

APPENDIX D SUMMARY OF THE INCIDENCE OF NONNEOPLASTIC
 

LESIONS IN MICE TREATED WITH TBP D-l
 

ix
 
LIST OF ILLUSTRATIONS
 

Figure Number Page 

1 GROWTH CURVES FOR TBP CHRONIC STUDY RATS 19 

2 SURVIVAL COMPARISONS OF TBP CHRONIC STUDY 

RATS 20 

3 GROWTH CURVES FOR TBP CHRONIC STUDY MICE 36 

4 SURVIVAL COMPARISONS OF TBP CHRONIC STUDY 

MICE 37 

LIST OF TABLES 

Table Number Page 

1 DESIGN SUMMARY FOR FISCHER 344 RATS—TBP 

FEEDING EXPERIMENT 10 

2 DESIGN SUMMARY FOR B6C3F1 MICE--TBP FEEDING 

EXPERIMENT 11 

3 ANALYSES OF THE INCIDENCE OF PRIMARY TUMORS 

AT SPECIFIC SITES IN MALE RATS TREATED WITH 

TBP 24 

4 ANALYSES OF THE INCIDENCE OF PRIMARY TUMORS 

AT SPECIFIC SITES IN FEMALE RATS TREATED 

WITH TBP 29 

5 ANALYSES OF THE INCIDENCE OF PRIMARY TUMORS 

AT SPECIFIC SITES IN MALE MICE TREATED WITH 

TBP 44 

6 ANALYSES OF THE INCIDENCE OF PRIMARY TUMORS 

AT SPECIFIC SITES IN FEMALE MICE TREATED 

WITH TBP 48 

Al SUMMARY OF THE INCIDENCE OF NEOPLASMS IN 

MALE RATS TREATED WITH TPB A-3 

A2 SUMMARY OF THE INCIDENCE OF NEOPLASMS IN 

FEMALE RATS TREATED WITH TBP A-8 

X
 
LIST OF TABLES (Concluded) 

Table Number Page 

Bl SUMMARY OF THE INCIDENCE OF NEOPLASMS IN 

MALE MICE TREATED WITH TBP B-3 

B2 SUMMARY OF THE INCIDENCE OF NEOPLASMS IN 

FEMALE MICE TREATED WITH TBP B-7 

Cl SUMMARY OF THE INCIDENCE OF NONNEOPLASTIC 

LESIONS IN MALE RATS TREATED WITH TBP C-3 

C2 SUMMARY OF THE INCIDENCE OF NONNEOPLASTIC 

LESIONS IN FEMALE RATS TREATED WITH TBP C-8 

Dl SUMMARY OF THE INCIDENCE OF NONNEOPLASTIC 

LESIONS IN MALE MICE TREATED WITH TBP D-3 

D2 SUMMARY OF THE INCIDENCE OF NONNEOPLASTIC 

LESIONS IN FEMALE MICE TREATED WITH TBP D-7 

xi
 

I. INTRODUCTION
 

Tris (2,3-dibromopropyl) phosphate (TBP) (NCI No. C03270) is a
 

compound that has been widely used as a flame retardant for synthetic
 

fabrics, particularly those made into sleepwear for infants and young
 

children. Because of the potential for ingestion (via mouthing habits) and extensive dermal exposure of youngsters to this compound,
 

and as a result of the minimal amount of data available from chronic
 

studies, TBP was selected for inclusion in the National Cancer Institute (NCI) Carcinogenesis Testing Program.
 

The Chemical Abstracts Service (CAS) Ninth Collective Index
 

(1977) name for this compound is 2,3-dibromo-l-propanol phosphate
 

(3:1). It is also known as tris (dibromopropyl) phosphate; Fire-


master T23P; or simply as Tris or TBP.
 

Because of its low cost, effectiveness in relation to other
 

chemicals, ease of application to synthetics, and general availability, TBP is one of the most widely utilized flame retardants (Daniher,
 

1976). It has been reported that approximately 3 x 10 pounds of the
 

chemical have been used annually by the U.S. textiles industry in
 

recent years (Osterberg, 1976). The compound is primarily used to
 

treat such fabrics as polyester, acetate, and triacetate (Simpson,
 

1976). In addition to its use by the textile industry, TBP is also
 

a fire retardant additive for polystyrene and polyurethane foams,
 

"*
 

The CAS registry number is 126-72-7.
 

1
 
polyvinyl chloride and phenolic resins, intumescent and nonintumescent paints, paper coatings, and rubber.
 

Exposure to TBP occurs in the general population primarily among
 

those who wear TBP-treated garments. In April 1976, the U.S. Consumer
 

Product Safety Commission estimated that approximately 60 percent of
 

childrens" sleepwear was treated with TBP (Simpson, 1976). Occupational exposure of workers in the textile industry as well as in other
 

TBP-utilizing industries is also likely.
 

Studies conducted by St. John et al. (1976) and Brieger et al.
 

(1968) failed to indicate any evidence of TBP absorption following
 

dermal contact with treated fabric. However, TBP applied directly
 

to the skin of rats and humans was subsequently absorbed (St. John
 

et al., 1976). The surface concentration of TBP varies among fabrics
 

but most surface TBP can be washed out. After three laundering
 

cycles, the surface concentration of a polyester fabric sample was
 

reduced from an initial level of 4300 ppm to 65 ppm and an acetate
 

fabric sample from 600 ppm to 90 ppm (Morrow et al., 1976). TBP may
 

be extracted from treated fabric by saliva (Brieger et al., 1968).
 

Thus, infants and young children who mouth blankets and clothing may
 

experience chronic exposure through ingest ion as well as dermal absorption. TBP was shown to cause dose-related allergic sensitization
 

in human subjects exposed to the chemical under conditions of maximization testing (Morrow et al., 1976), and the chemical was judged by
 

the authors to be a weak to mild sensitizer.
 

2
 
Positive results were noted in an in vitro test system utilizing
 

increases in DNA repair activity of human cells exposed to the test
 

chemical as an indicator of chemically induced damage to the genetic
 

material (Stich, 1976). TBP was also found to induce basepair
 

substitution mutations in a histidine-requiring strain of Salmonella
 

typhimurium (the Ames Test using Strain TA 1535) (Prival et al.,
 

1977). Mutagenic activity was extractable from TBP-treated fabrics
 

even after three cycles of laundering with detergent (Prival et al.,
 

1977).
 
II. MATERIALS AND METHODS 

A. Chemicals
 

The tris (2,3-dibromopropyl) phosphate (TBP) utilized for the
 

chronic bioassay was manufactured by Michigan Chemical Corporation
 

under the trade name Firemaster LV-T23P. The compound was analyzed
 

by Midwest Research Institute. Thin-layer chromatography was performed utilizing two solvent systems (benzene:icopropanol and chloroform: ethyl ac.etate). Each plate showed only one spot. High-pressure
 

liquid chromatography (Waters ALC/CPL 301) showed the presence of one
 

homogeneous peak. Nuclear Magnetic Resonance (Varian AA 100) spectra
 

conformed to reference spectra provided by Sadtler Research for
 

Firemaster-grade tris (2,3-dibromopropyl) phosphate. Infrared analysis was consistent with the structure of the compound and no extraneous peaks were noted.
 

Throughout this report the term TBP is used in referring to this
 

material.
 

To determine the concentration of 1,2-dibromo-3-chloropropane
 

(DBCP) present as a contaminant in the batch of TBP used in this
 

bioassay, analyses were performed at Midwest Research Institute using
 

vapor-phase chromatography. No DBCP was detected using methodology
 

providing a sensitivity of 100 ppm.
 

B. Dietary Preparation
 

The basal laboratory diet for both treated and control animals
 

was Wayne Lab-Blox (Allied Mills, Inc., Chicago, Illinois). TBP was
 

4
 
administered to the treated animals as a component of the diet. The 

® chemical was mixed with ground Wayne Lab-Blox meal using a 6 kg 

capacity Patterson-Kelley twin-shell stainless-steel V-blender. The 

treated diets were prepared once weekly and stored at 4°C.
 

C. Animals
 

Two animal species, rats and mice, were used in the carcinogenicity bioassay. Fischer 344 rats and B6C3F1 mice were obtained through
 

contracts of the Division of Cancer Treatment, National Cancer Institute. Animals of both species were supplied by the Frederick Cancer
 

Research Center, Frederick, Maryland. Treated and control animals
 

for both species were received in separate shipments.
 

Upon arrival, a random sample of animals was examined for nematode infestation and other signs of disease. The remaining animals
 

were quarantined for 2 weeks prior to initiation of test. Animals
 

were assigned to groups and distributed among cages so that average
 

body weight per cage was approximately equal for a given sex and
 

species.
 

D. Animal Maintenance
 

All animals were housed by species in rooms having a temperature
 

®
 

range of 23° to 34°C. Incoming air was filtered through Tri-Dek<
 

®
 15/40 denier Dacron filters (Tri-Dim Filter Corp., Hawthorne, New
 

Jersey) providing six changes of room air per hour. Fluorescent
 

lighting was provided on a 12-hour-daily cycle.
 

5
 
Rats were housed five per cage by sex in suspended polycarbonate
 

cages equipped with nonwoven fiber filter sheets. For the first 8
 

®
 months of test, corncob bedding (SAN-I-CEL , Paxton Processing Company, Paxton, Illinois) was supplied. Hardwood chips (Aspen bedding,
 

American Excelsior Company, Baltimore, Maryland) were substituted for
 

the remainder of the study. Bedding and clean cages were provided
 

two or three times weekly. Stainless steel cage racks (Fenco Cage
 

Products, Boston, Massachusetts) were cleaned once every two weeks
 

and disposable filters were replaced with the same frequency.
 

Mice were housed five per cage by sex in shoe box type polycarbonate cages fitted with stainless steel lids (Lab Products, Inc.,
 

Garfield, New Jersey) and nonwoven fiber filter bonnets. Ground
 

corncob bedding (Bed-o-Cobs , The Andersons Cob Division, Maumee,
 

Ohio) was supplied for the first 4 months of test. Thereafter, it
 

was replaced by Aspen bedding. Clean cages, lids, and bedding were
 

provided twice weekly. Reusable filters and pipe racks were sanitized once every 2 weeks throughout the study.
 

Food and water were available ad libitum. Water was available
 

from 250 ml polycarbonate water bottles equipped with rubber stoppers
 

and stainless steel sipper tubes. Bottles were replaced twice weekly
 

and, for rats only, water was supplied as needed between changes.
 

All rats used in this study were housed in a room with other
 

*
 

rats receiving diets containing 2-chloro-p-phenylenediamine sulfate
 

*
 CAS registry numbers are given in parentheses.
 

6
 
(61702-44-1); o-anisidine hydrochloride (134-29-0); and p-anisidine
 

hydrochloride (20265-97-8).
 

All mice used in this study were housed with other mice receiving
 

diets containing o-anisidine hydrochloride (134-29-0); N-(l-naphthyl)
 

ethylenediamine dihydrochloride (1465-25-4);2-chloro-p-phenylenediamine sulfate (61702-44-1); p-anisidine hydrochloride (20265-97-8);
 

2,3,5,6-tetrachloro-4-nitroanisole (2438-88-2); aniline hydrochloride
 

(142-04-1); and acetone (67-64-1).
 

E. Selection of Initial Concentrations
 

In order to establish the maximum tolerated concentrations of
 

TBP for use in the chronic study, subchronic toxicity tests were conducted with both rats and mice. Animals of each species were distributed among six groups, each consisting of five males and five
 

females. TBP in corn oil was administered by gavage to five of the
 

six rat groups at dosages of 1, 3, 10, 30, and 100 mg/kg/day and five
 

of the six mouse groups at dosages of 10, 30, 100, 300, and 1000 mg/
 

kg/day. The sixth group of each species served as a control group,
 

receiving only corn oil. Intubation was performed 5 days a week for
 

8 weeks.
 

In male rats a slight depression in mean body weight was observed at 30 and 100 mg/kg/day and one animal died at 100 mg/kg/day.
 

No depression in mean body weight or mortality were seen in the female
 

rats. The high dose selected for the chronic study was 10 mg/kg/day
 

for rats of both sexes. Slight depression in mean body weight was
 

7
 
observed in male mice at 300 mg/kg/day. Two males and three females
 

died at 1000 mg/kg/day. The high dose selected for the chronic study
 

was 100 mg/kg/day for mice of both sexes.
 

In the chronic study, TBP was administered in the diet (instead
 

of by gavage) at a concentration of 0.01 percent (100 ppm) for rats
 

and 0.1 percent (1000 ppm) for mice. Expressed in mg/kg/day, the
 

initial dosage for rats was approximately 5 mg/kg/day, 50 percent of
 

the intended dosage (of 10 mg/kg/day), and in mice it was approximately 160 mg/kg/day, 160 percent of the intended dosage. Because
 

mean body weight in both species increased during the chronic study
 

at a faster rate than food consumption, dosages on a body weight
 

basis would progressively decrease to a slight extent. Taking this
 

effect into account, it is estimated that during the chronic study
 

the time-weighted average dose for rats would have been about 40 percent and for mice about 140 percent of the intended dosage. These
 

estimates are consistent with the lack of body weight effect in the
 

rats and the definite compound-related depression of mean body weight
 

observed in mice.
 

F. Experimental Design
 

The experimental design parameters for the chronic study (species, sex, group size, concentrations administered, and duration of
 

*
 

The conversion was based on an estimated average body weight, during
 

the subchronic study, of 200 g/rat and 25 g/mouse, and food consumption of 10 g/day/rat and 4 g/day/mouse.
 

8 
treated and untreated observation periods) are summarized in Tables
 

1 and 2.
 

The low dose, high dose, and control rats were all approximately
 

6 weeks old at the time they were placed on test. Control rats were
 

placed on test one week earlier than treated rats. The high and low
 

dietary concentrations of TBP were 100 and 50 ppm, respectively.
 

Treated rats were supplied with dosed feed for a total of 103 weeks
 

followed by a 1- or 2-week observation period.
 

The low dose, high dose, and control mice were all approximately
 

6 weeks old at the time they were placed on test but control mice were
 

placed on test 2 months earlier than treated mice. The high and low
 

dietary concentrations of TBP administered to males and females were
 

1000 and 500 ppm, respectively. Treated mice were supplied with dosed
 

feed for a total of 103 weeks followed by a 1-week observation period.
 

G.	 Clinical and Histopathologic Examinations
 

Animals were weighed immediately prior to initiation of the experiment. Body weights were recorded twice weekly for the first 12
 

weeks of the study and at monthly intervals thereafter. From the
 

first day, all animals were inspected twice daily for mortality.
 

Food consumption, for two cages from each group, was monitored for
 

seven consecutive days once a month for the first nine months of the
 

bioassay and for three consecutive days each month thereafter. The
 

presence of tissue masses and lesions was determined by monthly
 

observation and palpation of each animal.
 

9 
TABLE 1
 

DESIGN SUMMARY FOR FISCHER 344 RATS
 

TBP FEEDING EXPERIMENT
 

MALE
 

CONTROL
 

LOW DOSE
 

HIGH DOSE
 

FEMALE
 

CONTROL
 

LOW DOSE
 

HIGH DOSE
 

INITIAL TBP 

GROUP CONCENSIZE TRATION3 

55 0 

55 50 

0 

55 100 

0 

55 0 

55 50 

0 

55 100 

0 

Concentrations in parts per million.
 

10 

OBSERVATION PERIOD
 

TREATED UNTREATED
 

(WEEKS) (WEEKS)
 

107
 

103
 

1
 

103
 

1
 

107
 

103
 

1
 

103
 

2
 
TABLE 2
 

DESIGN SUMMARY FOR B6C3F1 MICE
 

TBP FEEDING EXPERIMENT
 

MALE
 

CONTROL
 

LOW DOSE
 

HIGH DOSE
 

FEMALE
 

CONTROL
 

LOW DOSE
 

HIGH DOSE
 

INITIAL TBP 

GROUP CONCENSIZE TRATION3 

55 0 

50 500 

0 

50 1000 

0 

55 0 

50 500 

0 

50 1000 

0 

Concentrations in parts per million.
 

11 

OBSERVATION PERIOD
 

TREATED UNTREATED
 

(WEEKS) (WEEKS)
 

105
 

103
 

1
 

103
 

1
 

105
 

103
 

1
 

103
 

1
 
A necropsy was performed on each animal regardless of whether it
 

died, was killed when moribund, or was sacrificed at the end of the
 

bioassay. The animals were euthanized by carbon dioxide inhalation,
 

and were immediately necropsied. The histopathologic examination consisted of gross and microscopic examination of major tissues, organs,
 

or gross lesions taken from sacrificed animals and, whenever possible,
 

from animals found dead.
 

Slides were prepared from the following tissues: skin, subcutaneous tissue, lungs and bronchi, trachea, bone marrow, spleen, lymph
 

nodes, thymus, heart, salivary gland, liver, gallbladder (mice), pancreas, esophagus, stomach, small intestine, large intestine, kidney,
 

urinary bladder, pituitary, adrenal, thyroid, parathyroid, testis,
 

prostate, brain, eye, uterus, mammary gland, and ovary.
 

Tissues for which slides were prepared were preserved in 10 percent buffered formalin, embedded in paraffin, sectioned, and stained
 

with hematoxylin and eosin prior to microscopic examination. An
 

occasional section was subjected to special staining techniques for
 

more definitive diagnosis.
 

A few tissues were not examined for some animals, particularly
 

for those that died early. Also, some animals were missing, cannibalized, or judged to be in such an advanced state of autolysis as
 

to preclude histopathologic interpretation. Thus, the number of animals for which particular organs, tissues, or lesions were examined
 

12
 
microscopically varies and does not necessarily represent the number
 

of animals that were placed on experiment in each group.
 

H. Data Recording and Statistical Analyses
 

Pertinent data on this experiment have been recorded in an automatic data processing system, the Carcinogenesis Bioassay Data System
 

(Linhart et al., 1974). The data elements include descriptive information on the chemicals, animals, experimental design, clinical observations, survival, body weight, and individual pathologic results,
 

as recommended by the International Union Against Cancer (Berenblum,
 

1969). Data tables were generated for verification of data transcription and for statistical review.
 

These data were analyzed using the statistical techniques described in this section. Those analyses of the experimental results
 

that bear on the possibility of carcinogenicity are discussed in the
 

statistical narrative sections.
 

Probabilities of survival were estimated by the product-limit
 

procedure of Kaplan and Meier (1958) and are presented in this report
 

in the form of graphs. Animals were statistically censored as of the
 

time that they died of other than natural causes or were found to be
 

missing; animals dying from natural causes were not statistically
 

censored. Statistical analyses for a possible dose-related effect
 

on survival used the method of Cox (1972) when testing two groups for
 

equality and used Tarone's (1975) extensions of Cox's methods when
 

testing a dose-related trend. One-tailed P-values have been reported
 

13 
for all tests except the departure from linearity test, which is only
 

reported when its two-tailed P-value is less than 0.05.
 

The incidence of neoplastic or nonneoplastic lesions has been
 

given as the ratio of the number of animals bearing such lesions at a
 

specific anatomic site (numerator) to the number of animals in which
 

that site was examined (denominator). In most instances, the denominators included only those animals for which that site was examined
 

histologically. However, when macroscopic examination was required
 

to detect lesions prior to histologic sampling (e.g., skin or mammary
 

tumors), or when lesions could have appeared at multiple sites (e.g.,
 

lymphomas), the denominators consist of the numbers of animals necropsied.
 

The purpose of the statistical analyses of tumor incidence is to
 

determine whether animals receiving the test chemical developed a significantly higher proportion of tumors than did the control animals.
 

As a part of these analyses, the one-tailed Fisher exact test (Cox,
 

1970, pp. 48-52) was used to compare the tumor incidence of a control
 

group to that of a group of treated animals at each dose level. When
 

results for a number of treated groups, k, are compared simultaneously
 

with those for a control group, a correction to ensure an overall
 

significance level of 0.05 may be made. The Bonferroni inequality
 

(Miller, 1966, pp. 6-10) requires that the P-value for any comparison
 

be less than or equal to 0.05/k. In cases where this correction was
 

14
 
used, it is discussed in the narrative section. It is not, however,
 

presented in the tables, where the Fisher exact P-values are shown.
 

The Cochran-Armitage test for linear trend in proportions, with
 

continuity correction (Armitage, 1971, pp. 362-365), was also used
 

when appropriate. Under the assumption of a linear trend, this test
 

determined if the slope of the dose-response curve is different from
 

zero at the one-tailed 0.05 level of significance. Unless otherwise
 

noted, the direction of the significant trend was a positive dose relationship. This method also provides a two-tailed test of departure
 

from linear trend.
 

A time-adjusted analysis was applied when numerous early deaths
 

resulted from causes that were not associated with the formation of
 

tumors. In this analysis, deaths that occurred before the first
 

tumor was observed were excluded by basing the statistical tests on
 

animals that survived at least 52 weeks, unless a tumor was found at
 

the anatomic site of interest before week 52. When such an early
 

tumor was found, comparisons were based exclusively on animals that
 

survived at least as long as the animal in which the first tumor was
 

found. Once this reduced set of data was obtained, the standard procedures for analyses of the incidence of tumors (Fisher exact tests,
 

Cochran-Armitage tests, etc.) were followed.
 

When appropriate, life-table methods were used to analyze the
 

incidence of tumors. Curves of the proportions surviving without an
 

observed tumor were computed as in Saffiotti et al. (1972). The week
 

15
 
during which animals died naturally or were sacrificed was entered
 

as the time point of tumor observation. Cox's methods of comparing
 

these curves were used for two groups; Tarone's extension to testing
 

for linear trend was used for three groups. The statistical tests for
 

the incidence of tumors which used life-table methods were one-tailed
 

and, unless otherwise noted, in the direction of a positive dose
 

relationship. Significant departures from linearity (P < 0.05, two-


tailed test) were also noted.
 

The approximate 95 percent confidence interval for the relative
 

risk of each dosed group compared to its control was calculated from
 

the exact interval on the odds ratio (Gart, 1971). The relative risk
 

is defined as p /p where p is the true binomial probability of the
 

incidence of a specific type of tumor in a treated group of animals
 

and p is the true probability of the spontaneous incidence of the
 

c
 

same type of tumor in a control group. The hypothesis of equality
 

between the true proportion of a specific tumor in a treated group
 

and the proportion in a control group corresponds to a relative risk
 

of unity. Values in excess of unity represent the condition of a
 

larger proportion in the treated group than in the control.
 

The lower and upper limits of the confidence interval of the
 

relative risk have been included in the tables of statistical analyses. The interpretation of the limits is that in approximately 95
 

percent of a large number of identical experiments, the true ratio
 

of the risk in a treated group of animals to that in a control group
 

16
 
would be within the interval calculated from the experiment. When
 

the lower limit of the confidence interval is greater than one, it
 

can be inferred that a statistically significant result (a P < 0.025
 

one-tailed test when the control incidence is not zero, P < 0.050
 

when the control incidence is zero) has occurred. When the lower
 

limit is less than unity but the upper limit is greater than unity,
 

the lower limit indicates the absence of a significant result while
 

the upper limit indicates that there is a theoretical possibility
 

of the induction of tumors by the test chemical which could not be
 

detected under the conditions of this test.
 

17 
III.	 CHRONIC TESTING RESULTS: RATS
 

A.	 Body Weights and Clinical Observations
 

No appreciable differences in mean body weight between dosed
 

and control rats were noted (Figure 1).
 

Subcutaneous palpable masses were observed in all male groups,
 

but with a higher frequency in the treated animals. Protrusion, discoloration, and encrustation of the eyes and jaundice were noted in
 

both treated and control male groups. Yellowing of the eyes was reported only in the treated male groups. Emaciation was observed only
 

in the treated males. A urogenital bloody exudate was noted in few
 

low dose males. High numbers of females in the control, low dose,
 

and high dose groups were observed to have palpable subcutaneous
 

masses. Discoloration, protrusion, and encrustation of the eyes were
 

noted in all female groups but occurred more frequently among high
 

dose females. Alopecia, not associated with visible lesions, was
 

also observed in all groups but with a higher frequency in the controls (10/55 controls, 2/50 low dose, 1/50 high dose).
 

B. Survival
 

The estimated probabilities of survival for male and female rats
 

in the control and TBP-dosed groups are shown in Figure 2.
 

For both male and female rats the Tarone test indicated no significant association between increased dosage and accelerated mortality. In male rats, 73 percent (40/55) of the high dose, 64 percent
 

(35/55) of the low dose, and 71 percent (39/55) of the control group
 

18 
TIME ON TEST (WEEKS) 

FIGURE 1 

GROWTH CURVES FOR TBP CHRONIC STUDY RATS 

19 
TIME ON TEST (WEEKS) 

FIGURE 2 

SURVIVAL COMPARISONS OF TBP CHRONIC STUDY RATS 

20 
lived to the end of the test. In female rats, 65 percent (36/55) of
 

the high dose, 80 percent (44/55) of the low dose, and 65 percent
 

(36/55) of the control group survived to termination of the study.
 

Thus, an adequate number of rats in all groups survived sufficiently
 

long to be at risk from late-developing tumors.
 

C. Pathology
 

Histopathologic findings on neoplasms in rats are tabulated in
 

Appendix A (Tables Al and A2); findings on nonneoplastic lesions are
 

tabulated in Appendix C (Tables Cl and C2).
 

Renal tubular-cell adenomas were seen in 26/54 (48 percent) low
 

dose and 26/54 (48 percent) high dose males, and in 4/54 (7 percent)
 

low dose and 10/54 (19 percent) high dose females but no tumors of
 

the renal tubular epithelium were found in either male or female controls. The renal tubular-cell adenomas found in treated rats varied
 

in size from microscopic lesions having a diameter of three or four
 

normal tubules to much larger tumors. All such lesions consisted of
 

nodules of poorly organized tubules compressing the surrounding parenchyma. Cytoplasm was markedly basophilic and nuclei were vesicular
 

with a prominent small nucleolus. Multiple tubular adenomas were
 

frequently observed.
 

Three of 54 (6 percent) high dose males had tumors classified
 

as renal-cell carcinomas (tubular-cell adenocarcinomas). These were
 

much larger than the adenomas, sometimes bulging through the kidney
 

capsule. The cellular pattern suggested elongated, poorly organized
 

21
 
tubules interspersed with large areas of hemorrhage and necrosis.
 

Cytoplasm was abundant, weakly acidophilic, and often foamy and
 

vacuolated. Nuclei showed marked pleomorphism and occasional mitotic
 

figures.
 

The only nonneoplastic lesions that appeared to be related to TBP
 

administration occurred in the renal tubules. In 6/54 (11 percent)
 

high dose males and 35/54 (65 percent) high dose females, a few tubular cells were slightly enlarged and showed nuclear dysplasia consisting of nuclear enlargement, chromatin clumping, and parachromatin
 

clearing. These lesions were not observed in the control or low dose
 

groups. Kidney tumors were not observed in those rats for which
 

dysplasia was reported.
 

Selected kidney slides from male and female high dose and control rats were stained with an acid fast stain and examined microscopically. No evidence of acid fast intranuclear inclusions in the
 

renal epithelial cells suggestive of toxicity from lead or certain
 

other heavy metal compounds was found.
 

A variety of neoplasms were observed with similar frequencies in
 

treated and control rats. The most common of these among male rats
 

were interstitial-cell tumors of the testes, leukemia and malignant
 

lymphomas, adrenal pheochromocytoma, and pituitary chromophobe
 

adenoma. Tumors occurring with similar frequencies in treated and
 

control female rats include leukemia, pituitary tumors (carcinomas,
 

chromophobe adenomas, and basophil adenomas), mammary gland fibroadenoma, and endometrial stromal polyp.
 

22
 
TBP feeding had no apparent effect on the incidence of chronic
 

nephritis commonly seen in aged rats, especially males. Nonneoplastic degenerative or inflammatory lesions were seen in all groups of
 

both sexes. Their incidence was not related to feeding with this
 

compound.
 

Under the conditions of this bioassay, there was histopathologic
 

evidence for the carcinogenicity of TBP in Fischer 344 rats, as feeding TBP was associated with neoplasms of the renal tubules.
 

D. Statistical Analyses of Results
 

The results of the statistical analyses of tumor incidence in
 

rats are summarized in Tables 3 and 4. The analysis is included for
 

every type of malignant tumor in either sex where at least two such
 

tumors were observed in at least one of the control or TBP-dosed
 

groups and where such tumors were observed in at least 5 percent of
 

the group.
 

In both male and female dosed rats the incidence of tubular-cell
 

neoplasms of the kidney was significant. For females the Cochran-


Armitage test indicated a significant (P = 0.001) positive association between dosage and the incidence of tubular-cell adenomas. The
 

Fisher exact test confirmed this result with a significantly (P =
 

0.001) higher incidence in the high dose than in the control group.
 

For males, when incidences were combined so that the numerator
 

represented rats with either a tubular-cell adenoma or a tubular-cell
 

adenocarcinoma of the kidney, the Cochran-Armitage test and both
 

23 
___ 

TABI3 3
 

ANALYSES OF THE INCIDENCE OF PRIMARY TUMORS AT SPECIFIC SITES
 

IN MALE RATS TREATED WITH TBP*
 

TOPOGRAPHY : MORPHOLOGY 

Lung: Alveolar /Bronchi olar Adenoma or 

Alveolar/Bronchiolar Carcinoma*5 

P Values 

Departure from Linear Trend 

Relative Risk (Control) 

Lower Limit 

Upper Limit 

Weeks to First Observed Tumor 

Hematopoietic System: Leukemia 

P Values0 

Relative Risk (Control) 

Lower Limit 

Upper Limit 

Weeks to First Observed Tumor 

Liver: Neoplastic Nodule or Hepatocellular 

Carcinoma" 

P Values 

Relative Risk (Control) 

Lower Limit 

Upper Limit 

Weeks to First Observed Tumor 

CONTROL 

0/54(0.00) 

N.S. 

P = 0.014 

17/54(0.31) 

P = 0.013(N) 

85 

0/54(0.00) 

P = 0.026 

LOW 

DOSE 

3/55(0.05) 

N.S. 

Infinite 

0.589 

Infinite 

95 

13/55(0.24) 

N.S. 

0.751 

0.375 

1.472 

80 

1/55(0.02) 

N.S. 

Infinite 

0.053 

Infinite 

99 

HIGH 

DOSE 

0/55(0.00) 

N.S. 

7/55(0.13) 

P = 0.016(N) 

0.404 

0.154 

0.935 

84 

4/54(0.07) 

N.S. 

Infinite 

0.925 

Infinite 

84 

24

 
___ 

25 

TOPOGRAPHY : MORPHOLOGY
 

Kidney: Tubular-Cell Adenoma
 

P Values0
 

o
 

Departure from Linear Trend
 

Relative Risk (Control)
 

Lower Limit
 

Upper Limit
 

Weeks to First Observed Tumor
 

Kidney: Tubular-Cell Adeno care in oma
 

P Values0
 

Relative Risk (Control)
 

Lower Limit
 

Upper Limit
 

Weeks to First Observed Tumor
 

Kidney: Tubular -Cell Adenoma or
 

Tubular- Cell Adeno care inoma
 

P Values '
 

Departure from Linear Trend
 

Relative Risk (Control)
 

Lower Limit
 

Upper Limit
 

Weeks .0 First Observed Tumor
 

TABLE 3 (CONTINUED) 

CONTROL
 

0/53(0.00)
 

P < 0.001
 

P = 0.002
 

0/53(0.00)
 

P = 0.038
 

0/53(0.00)
 

P < 0.001
 

P = 0.009
 

_.—
 

LOW
 

DOSE
 

26/54(0.48)
 

P < 0.001
 

Infinite
 

8.387
 

Infinite
 

76
 

0/54(0.00)
 

N.S.
 

_—
 

26/54(0.48)
 

P < 0.001
 

_«^
 

Infinite
 

8.387
 

Infinite
 

76
 

HIGH
 

DOSE
 

26/54(0.48)
 

P < 0.001
 

Infinite
 

8.387
 

Infinite
 

82
 

3/54(0.06)
 

N.S.
 

Infinite
 

0.589
 

Infinite
 

40
 

29/54(0.54)
 

P < 0.001
 

Infinite
 

9.429
 

Infinite
 

40
 
___ 

___ 

___ 

26

 

TOPOGRAPHY: MORPHOLOGY
 

Pituitary: Chromophobe Adenoma
 

P Values0
 

Relative Risk (Control)
 

Lower Limit
 

Upper Limit
 

Weeks to First Observed Tumor
 

Pituitary: Basophil Adenoma
 

P Values0
 

Relative Risk (Control)
 

Lower Limit
 

Upper Limit
 

Weeks to First Observed Tumor
 

Adrenal: Pheochro'iocytoma or ,
 

Pheochromocy toma, Malignant
 

P Values0
 

Relative Risk (Control)
 

Lower Limit
 

Upper Limit
 

Weeks to First Observed Tumor
 

TABLE 3 (CONTINUED) 

CONTROL
 

4/48(0.08)
 

N.S.
 

91
 

0/48(0.00)
 

N.S.
 

14/54(0.26)
 

N.S.
 

74
 

LOW
 

DOSE
 

7/50(0.14)
 

N.S.
 

1.680
 

0.459
 

7.369
 

92
 

3/50(0.06)
 

N.S.
 

Infinite
 

0.578
 

Infinite
 

76
 

11/55(0.20)
 

N.S.
 

0.771
 

0.349
 

1.660
 

80
 

HIGH
 

DOSE
 

3/50(0.06)
 

N.S.
 

0.720
 

0.111
 

4.035
 

84
 

2/50(0.04)
 

N.S.
 

Infinite
 

0.284
 

Infinite
 

104
 

16/55(0.29)
 

N.S.
 

1.122
 

0.572
 

2.228
 

81
 
27

 

TABLE 3 (CONTINUED) 

TOPOGRAPHY : MORPHOLOGY CONTROL 

Thyroid: C-Cell Adenoma or C-Cell Carcinoma 3/53(0.06) 

P Values N.S. 

Relative Risk (Control) 

Lower Limit 

Upper Limit 

Weeks to First Observed Tumor 107 

Pancreatic Islets:

P Values0 

 Islet-Cell Adenoma 1/53(0.02) 

N.S. 

Relative Risk (Control) 

Lower Limit 

Upper Limit 

Weeks to First Observed Tumor 107 

Preputial Gland: Carcinoma NOS or

P Values 

 Adenocarcinoma 1/54(0.02) 

N.S. 

Relative Risk (Control) 

Lower Limit 

Upper Limit 

Weeks to First Observed Tumor 107 

LOW 

DOSE 

3/51(0.06) 

N.S. 

1.039 

0.145 

7.423 

104 

3/53(0.06) 

N.S. 

3.000 

0.250 

154.426 

95 

2/55(0.04) 

N.S. 

1.964 

0.105 

113.749 

90 

HIGH 

DOSE 

4/52(0.08) 

N.S. 

1.359 

0.242 

8.869 

104 

1/51(0.02) 

N.S. 

1.039 

0.013 

78.491 

84 

4/55(0.07) 

N.S. 

3.927 

0.406 

189.701 

77 
28 

TABLE 3 (CONCLUDED) 

LOW HIGH 

TOPOGRAPHY : MORPHOLOGY CONTROL DOSE DOSE 

Preputial Gland: Adenoma NOS or Carcinoma NOS or Ad eno carcinoma NOS^ 1/54(0.02) 3/55(0.05) 7/55(0.13) 

P Values0 P = 0.019 N.S. P = 0.032 ___ 

Relative Risk (Control) 2.946 6.873 

Lower Limit 0.246 0.931 

Upper Limit 151.741 303.440 

Weeks to First Observed Tumor 107 90 77 

Testis: Interstitial-Cell Tumor 53/54(0.98) 46/55(0.84) 50/55(0.91) 

P Values0 N.S. P = 0.009(N) N.S. Q 

Departure from Linear Trend P = 0.022 

Relative Risk (Control) 0.852 0.926 

Lower Limit 0.819 0.892 

Upper Limit 0.975 1.032 

Weeks to First Observed Tumor 74 41 40 

Treated groups received time-weighted average doses of 50 or 100 ppm in feed.
 

Number of tumor-bearing animals/number of animals examined at site (proportion).
 

C

The probability level for the Cochran-Armitage test is given beneath the incidence of tumors in
 

the control group when P < 0.05; otherwise, not significant (N.S.) is indicated. The probability
 

level for the Fisher exact test for the comparison of a treated group with the control group is
 

given beneath the incidence of tumors in the treated group when P < 0.05; otherwise, not significant (N.S.) is indicated. For both Cochran-Armitage and Fisher exact tests a negative designation (N) indicates a lower incidence in the treated group(s) thar in the control group.
 

The 95% confidence interval on the relative risk of the treated group to the control group,
 g


The probability level of the test for departure from linear trend is given beneath the control
 

group when P < 0.05.
 
___ 

___ 

TABLE 4
 

ANALYSES OF THE INCIDENCE OF PRIMARY TUMORS AT
 

SPECIFIC SITES IN FEMALE RATS TREATED WITH TBPa
 

HIGH
 

DOSE
 

9/55(0.16)
 

N.S.
 

0.982
 

0.375
 

2.577
 

82
 

10/54(0.19)
 

P = 0.001
 

Infinite
 

2.858
 

Infinite
 

89
 

1/52(0.02)
 

N.S.
 

0.308
 

0.006
 

3.679
 

105
 

TOPOGRAPHY: MORPHOLOGY
 

Hematopoietic System: Leukemia
 

P Values
 

Relative Risk (Control)
 

Lower Limit
 

Upper Limit
 

Weeks to First Observed Tumor
 

Kidney: Tubular-Cell Adenoma
 

P Values0
 

Relative Risk (Control)
 

Lower Limit
 

Upper Limit
 

Weeks to First Observed Tumor
 

Pituitary: Carcinoma NOS
 

P Values0
 

Relative Risk (Control)
 

Lower Limit
 

Upper Limit
 

Weeks to First Observed Tumor
 

CONTROL
 

9/54(0.17)
 

N.S.
 

91
 

0/52(0.00)
 

P = 0.001
 

3/48(0.06)
 

N.S.
 

90
 

LOW
 

DOSE
 

10/55(0.18)
 

N.S.
 

1.091
 

0.433
 

2.795
 

98
 

4/54(0.07)
 

N.S.
 

Infinite
 

0.891
 

Infinite
 

104
 

1/54(0.02)
 

N.S.
 

0.296
 

0.006
 

3.547
 

104
 

29

 
30

 

TOPOGRAPHY: MORPHOLOGY
 

Pituitary: Chromophobe Adenoma
 

P Values0
 

Relative Risk (Control)
 

Lower Limit
 

Upper Limit
 

Weeks to First Observed Tumor
 

Adrenal: Pheochromocytoma
 

P Values0
 

Relative Risk (Control)
 

Lower Limit
 

Upper Limit
 

Weeks to First Observed Tumor
 

Thyroid: C-Cell Adenoma or C-Cell
 

Carcinoma*3
 

P Values0
 

Relative Risk (Control)
 

Lower Limit
 

Upper Limit
 

Weeks to First Observed Tumor
 

TABLE 4 (CONTINUED)
 

CONTROL
 

15/48(0.31)
 

N.S.
 

74
 

3/53(0.06)
 

N.S.
 

107
 

4/49(0.08)
 

N.S.
 

_—
 

107
 

LOW
 

DOSE
 

22/54(0.41)
 

N.S.
 

1.304
 

0.738
 

2.369
 

94
 

4/53(0.08)
 

N.S.
 

1.359
 

0.242
 

8.869
 

104
 

3/53(0.06)
 

N.S.
 

0.693
 

0.106
 

3.896
 

104
 

HIGH
 

DOSE
 

24/52(0.46)
 

N.S.
 

1.477
 

0.854
 

2.627
 

86
 

2/54(0.04)
 

N.S.
 

0.654
 

0.057
 

5.484
 

104
 

4/53(0.08)
 

N.S.
 

0.925
 

0.182
 

4.709
 

98
 
___ 

31

 

TOPOGRAPHY: MORPHOLOGY
 

Mammary Gland: Fibroadenoma
 

c
 

P Values
 

Relative Risk (Control)
 

Lower Limit
 

Upper Limit
 

Weeks to First Observed Tumor
 

Clitoral Gland: Adenoma NOS
 

P Values0
 

Departure from Linear Trend
 

Relative Risk (Control)
 

Lower Limit
 

Upper Limit
 

Weeks to First Observed Tumor
 

Uterus: Endometrial Stromal Polyp
 

P Values0
 

Relative Risk (Control)
 

Lower Limit
 

Upper Limit
 

Weeks to First Observed Tumor
 

TABLE 4 (CONTINUED)
 

CONTROL
 

16/54(0.30)
 

N.S.
 

—_
 

99
 

0/54(0.00)
 

N.S.
 

P = 0.014
 

16/52(0.31)
 

N.S.
 

68
 

LOW
 

DOSE
 

10/55(0.18)
 

N.S.
 

0.614
 

0.275
 

1.303
 

99
 

3/55(0.05)
 

N.S.
 

Infinite
 

0.589
 

Infinite
 

100
 

14/54(0.26)
 

N.S.
 

0.843
 

0.434
 

1.682
 

104
 

HIGH
 

DOSE
 

19/55(0.35)
 

N.S.
 

1.166
 

0.640
 

2.152
 

42
 

0/55(0.00)
 

N.S.
 

11/55(0.20)
 

N.S.
 

0.650
 

0.308
 

1.373
 

98
 
32 

TABLE 4 (CONCLUDED)
 

TOPOGRAPHY : MORPHOLOGY CONTROL 

LOW 

DOSE 

HIGH 

DOSE 

Ovary: Sertoli-Cell Tumor 

P Values0 

0/53(0.00) 

P = 0.041 

0/53(0.00) 

N.S. 

3/55(0.05) 

N.S. 

Relative Risk (Control) 

Lower Limit 

Upper Limit 

Infinite 

0.578 

Infinite 

Weeks to First Observed Tumor 105 

Treated groups received time-weighted average doses of 50 or 100 ppm in feed.
 

Number of tumor-bearing animals/number of animals examined at site (proportion).
 

°The probability level for the Cochran-Armitage test is given beneath the incidence of tumors in
 

the control group when P < 0.05; otherwise, not significant (N.S.) is indicated. The probability
 

level for the Fisher exact test for the comparison of a treated group with the control group is
 

given beneath the incidence of tumors in the treated group when P < 0.05; otherwise, not significant (N.S.) is indicated. For both Cochran-Armitage and Fisher exact tests a negative designation (N) indicates a lower incidence in the treated group(s) than in the control group.
 

The 95% confidence interval on the relative risk of the treated group to the control group.
 

6

The probability level of the test for departure from linear trend is given beneath the control
 

group when P < 0.05.
 
Fisher exact tests were significant (P < 0.001). On the basis of
 

these results, there was a significant association between the administration of TBP and the increased incidence of tubular-cell adenomas
 

of the kidney in both male and female rats.
 

In male rats the Cochran-Armitage test indicated a significant
 

(P = 0.026) positive association between dosage and the combined
 

incidence of hepatocellular carcinomas and neoplastic nodules of the
 

liver. The Fisher exact tests, however, were not significant.
 

In male rats the Cochran-Armitage test indicated a significant
 

(P = 0.019) positive association between dosage and the combined incidence of adenomas, carcinomas, or adenocarcinomas of the preputial
 

gland. The Fisher exact test comparing the high dose to the control
 

group, however, had a probability level of P = 0.032, a marginal result which was not significant under the Bonferroni inequality.
 

In female rats the Cochran-Armitage test indicated a significant
 

(P = 0.041) positive association between dosage and the incidence of
 

Sertoli-cell tumors of the ovary. The Fisher exact tests, however,
 

were not significant.
 

The possibility of a negative association between dosage and incidence was noted for leukemia in male rats. This apparent negative
 

trend may result from the unusually high incidence of leukemia in the
 

control group (17/45 [31 percent]). The incidence in historical untreated male Fischer 344 control rats compiled by this laboratory for
 

the NCI Carcinogenesis Testing Program was 57/534 (11 percent).
 

33
 
The Fisher exact test indicated a significantly (P = 0.009)
 

lower incidence of interstitial-cell tumors of the testis in the low
 

dose males than in the control group. The Cochran-Armitage test and
 

the Fisher exact comparison of high dose to control, however, were
 

not significant.
 

For a number of tumors in both male and female rats the control
 

group had significantly (P < 0.05) higher incidences than was commonly
 

found in the historical control Fischer 344 rats at Mason Research
 

Institute for the NCI Carcinogenesis Testing Program. Among males,
 

26 percent (14/54) of the TBP control rats had pheochromocytoma compared with 12 percent (65/534) of the historical controls. Among TBP
 

control females, 30 percent (16/54) had mammary fibroadenomas and 31
 

percent (16/52) had endometrial stromal polyps of the uterus compared
 

to 19 percent (112/589) and 16 percent (95/589), respectively, in the
 

historical controls.
 

34
 
IV. CHRONIC TESTING RESULTS: MICE
 

A. Body Weights and Clinical Observations
 

Mean group body weights of TBP-treated mice of both sexes were
 

appreciably depressed relative to control mice during the chronic
 

bioassay (Figure 3). Mean body weights of high dose mice were only
 

slightly depressed, however, relative to low dose mice.
 

The clinical sign observed with the greatest frequency in both
 

males and females was alopecia (i.e., 42/55, 37/50, 43/50 in control,
 

low dose and high dose males, respectively, and 48/55, 39/50, 45/50
 

in control, low dose and high dose females, respectively). Other
 

clinical signs observed with much lower frequency in both sexes included palpable masses, abdominal distention, and exophthalmia. Distension in the urogenital area was reported in all male groups but in
 

no females, and emaciation was recorded for one low dose and one high
 

dose female but for no other animals.
 

B.	 Survival
 

The estimated probabilities of survival for male and female mice
 

in the control and TBP-dosed groups are shown in Figure 4.
 

The Tarone tests for association between increased dosage and
 

accelerated mortality were not significant for either male or female
 

mice. In males 86 percent (43/50) of the high dose, 76 percent
 

(38/50) of the low dose, and 80 percent (44/55) of the control mice
 

survived until the end of the study. In females 76 percent (38/50)
 

of the high dose, 74 percent (37/50) of the low dose and 80 percent
 

35
 
TIME ON TEST (WEEKS) 

FIGURES 

GROWTH CURVES FOR TBP CHRONIC STUDY MICE 

36 
TIME ON TEST (WEEKS) 

FIGURE 4 

SURVIVAL COMPARISONS OF TBP CHRONIC STUDY MICE 

37 
(44/55) of the control mice survived until the end of the study.
 

These high survival rates, plus the consideration that the mouse
 

study was run for 104 to 105 weeks, means that a sufficient number of
 

mice were at risk from late-developing tumors.
 

C. Pathology
 

Histopathologic findings on neoplasms in mice are tabulated in
 

Appendix B (Tables Bl and B2); findings on nonneoplastic lesions are
 

tabulated in Appendix D (Tables Dl and D2).
 

In treated males, renal tubular-cell adenoma occurred in 3/50
 

(6 percent) low dose and 9/49 (18 percent) high dose mice. In treated
 

females, there were renal tubular-cell adenomas in 2/50 (4 percent)
 

low dose and 2/46 (4 percent) high dose mice. No renal tubular-cell
 

adenomas were observed in control groups. Renal tubular-cell adenocarcinomas were observed in 1/50 (2 percent) low dose and 5/49 (10
 

percent) high dose males. Renal tubular-cell adenocarcinomas were
 

not observed in any treated females or in control mice of either sex.
 

Renal tubular-cell adenomas were composed of nodules of small,
 

well-organized neoplastic tubules compressing the surrounding parenchyma. The size of these lesions varied from the diameter of six or
 

seven normal tubules to a few millimeters. Cytoplasm of the tumor
 

cells tended to be acidophilic and the nuclei were rounded and uniform. Although mitotic figures were often seen, there were no nuclear characteristics of malignancy. Renal tubular-cell carcinomas
 

were much larger than adenomas, often invading the renal capsule.
 

38
 
Tubular organization was indistinct or absent. Cytoplasm was acidophilic and often contained large vacuoles. Nuclei varied in size,
 

shape, and chromatin pattern and occasional nucleoli were prominent.
 

Variable amounts of hemorrhage, necrosis, and calcification were
 

associated with renal tubular-cell carcinomas.
 

Renal tubular dysplasia was observed in 30/49 (61 percent) high
 

dose males, 37/50 (74 percent) low dose males, 12/46 (26 percent)
 

high dose females and 1/50 (2 percent) low dose females. In these
 

mice, normal tubular architecture was retained but occasional tubular
 

cells were hypertrophied and contained very large bizarre nuclei with
 

abnormal chromatin patterns and occasionally enlarged nucleoli.
 

Tubular dysplasia was not seen in any controls.
 

Selected kidney slides from male and female high dose and control mice were stained with an acid fast stain and examined microscopically. No evidence of acid fast intranuclear inclusions in the
 

renal epithelial cells suggestive of toxicity from lead or certain
 

other heavy metal compounds was found.
 

Squamous-cell papillomas of the forestomach were found in 10/47
 

(21 percent) low dose and 11/48 (23 percent) high dose males and in
 

10/48 (21 percent) low dose and 18/44 (41 percent) high dose females.
 

There were squamous-cell carcinomas of the forestomach in 2/48 (4
 

percent) high dose males, and in 4/48 (8 percent) low dose and 4/44
 

(9 percent) high dose females. No gastric neoplasms were found in 51
 

control males. There were squamous-cell papillomas of the forestomach
 

in 2/53 (4 percent) control females.
 

39
 
Squamous-cell papillomas were defined as papillary lesions
 

showing marked superficial hyperkeratosis. Beneath this was a thick
 

layer of acanthotic squamous epithelium. Chronic inflammation was
 

frequently found in the submucosa below the lesion, but the basal
 

layer of the epithelium appeared intact.
 

The squamous-cell carcinomas of the forestomach also often showed
 

superficial hyperkeratinization. However, the underlying epithelial
 

cells had lost their normal architecture. Nuclei were pleomorphic
 

with abundant normal and abnormal mitotic figures, variation in size
 

and shape, and bizarre chromatin patterns. The basal layer of epithelial cells appeared to have lost its cohesion so that tumor cells
 

grew down into the submucosa in a disorganized fashion and appeared
 

as small islands deep in the stomach wall.
 

Other malignant gastric tumors found in the treated mice but not
 

in the controls were a basal-cell carcinoma of the forestomach in a
 

high dose male and a leiomyosarcoma of the stomach wall in a high
 

dose female. There was one squamous-cell carcinoma of the esophagus
 

in a high dose female.
 

Bronchiolar/alveolar adenomas or carcinomas occurred in 12/54
 

(22 percent) control males, 18/44 (41 percent) low dose males, 25/50
 

(50 percent) high dose males, 4/55 (7 percent) control females, 9/50
 

(18 percent) low dose females, and 17/50 (34 percent) high dose females.
 

40
 
Bronchiolar/alveolar adenomas were well-circumscribed lesions
 

compressing the surrounding pulmonary parenchyma and often having
 

subpleural locations. Tumor cells were arranged in ribbons or in more
 

or less well-organized tubules. Cytoplasm was moderate in amount and
 

faintly basophilic. Individual cells tended to be columnar. Nuclei
 

were rounded and uniform with a normal chromatin pattern.
 

Bronchiolar/alveolar carcinomas tended to be larger than the
 

adenomas, but were actually differentiated from them by two characteristics: (1) nuclear pleomorphism with parachromatin clearing and an
 

abnormal chromatin pattern; and (2) a tendency to invade the surrounding parenchyma or neighboring bronchioles.
 

A dose-related increase in hepatocellular adenomas or carcinomas
 

was noted in female mice. The observed combined incidences of mice
 

with hepatocellular adenoma or hepatocellular carcinoma were 11/54
 

(20 percent) control females, 23/50 (46 percent) low dose females,
 

and 35/49 (71 percent) high dose females. In male mice, however, no
 

such dose-related increase in hepatocellular neoplasms was apparent.
 

Hepatocellular carcinomas were large lesions usually occupying
 

the bulk of a lobe and compressing adjacent normal parenchyma. They
 

showed no evidence of normal architectural pattern but consisted of
 

trabeculae arranged in random fashion, often around large sinusoids.
 

Cytoplasm was often abundant and faintly basophilic. Nuclei showed
 

varying degrees of pleomorphism, some resembling normal hepatocytes
 

and others having clearly abnormal chromatin patterns. Occasional
 

41
 
mitotic figures were seen. Some of these tumors invaded hepatic
 

blood vessels and a few metastasized, usually to the lung.
 

The distinction between hepatocellular carcinomas and hepatocellular adenomas was not always clear. Tumors classified as adenomas
 

were always smaller than carcinomas, occupying only a small portion
 

of a lobe. Basophilia and nuclear pleomorphism were less frequently
 

observed and no metastasis or vascular invasion were seen.
 

Cystadenomas of the Harderian gland were detected macroscopically and confirmed histologically in 0/55 control females, 4/50
 

(8 percent) low dose females, 2/50 (4 percent) high dose females,
 

1/55 (2 percent) control males, 1/50 (2 percent) low dose males and
 

2/50 (4 percent) high dose males. Since these lesions are rare, they
 

may represent an effect of TBP feeding even though they were observed
 

at low incidences and a dose-related effect was not apparent.
 

The Harderian gland tumors seen were small, well-circumscribed
 

lesions. Cells were arranged in large, well-organized glands, often
 

with a papillary component. Cell shapes varied from low cuboidal to
 

high columnar. Nuclei were round, dark, uniform, and placed at the
 

basal end in columnar cells. Cytoplasm was abundant and contained
 

innumerable small vacuoles.
 

Other tumors found in treated mice but not in the controls included one interstitial-cell tumor of the testis in a low dose male,
 

five assorted ovarian tumors (one malignant) in high dose females,
 

one ovarian granulosa-cell tumor in a low dose female, ten assorted
 

42
 
uterine tumors in low dose females, two endometrial stromal polyps
 

and one uterine adenocarcinoma in high dose females, and an osteoma
 

of the skull in a high dose female. Tumors found in the controls but
 

not in the treated mice included one mammary adenocarcinoma type B,
 

a follicular adenoma of the thyroid gland, and a thymoma (all in females) .
 

Nonneoplastic inflammatory or degenerative changes were occasionally seen in all groups of mice. Their nature and incidence could not
 

be related to TBP administration.
 

Under the conditions of this bioassay histopathologic evidence
 

was provided for the carcinogenicity of TBP in B6C3F1 mice because
 

feeding of TBP was associated with neoplasms of the renal tubules in
 

both sexes, marked increases in the incidence of squamous tumors of
 

the forestomach in both sexes, increases in the incidence of lung
 

tumors in both sexes, and increases in the incidence of hepatocellular
 

neoplasms in females.
 

D. Statistical Analyses of Results
 

The results of the statistical analyses of tumor incidence in
 

mice are summarized in Tables 5 and 6. The analysis is included for
 

every type of malignant tumor in either sex where at least two such
 

tumors were observed in at least one of the control or TBP-dosed
 

groups and where such tumors were observed in at least 5 percent of
 

the group.
 

43
 
TABLE 5
 

ANALYSES OF THE INCIDENCE OF PRIMARY TUMORS AT
 

SPECIFIC SITES IN MALE MICE TREATED WITH TBPa
 

44 

TOPOGRAPHY: MORPHOLOGY
 

Stomach: Squamous-Cell Carcinoma
 

P Values0
 

Relative Risk (Control)
 

Lower Limit
 

Upper Limit
 

Weeks to First Observed Tumor
 

Stomach: Squamous-Cell Papilloma or
 

Squamous-Cell Carcinoma"
 

P Values0
 

Relative Risk (Control)
 

Lower Limit
 

Upper Limit
 

Weeks to First Observed Tumor
 

Lung: Alveolar /Bronchiolar Carcinoma
 

P Values0
 

Relative Risk (Control)
 

Lower Limit
 

Upper Limit
 

Weeks to First Observed Tumor
 

LpW HIGH 

CONTROL DOSE DOSE 

0/51(0.00) 0/47(0.00) 2/48(0.04) 

N.S. N.S. 

Infinite 

0.314 

Infinite 

95 

0/51(0.00) 10/47(0.21) 13/48(0.27) 

P < 0.001 P < 0.001 P < 0.001 ___ 

Infinite Infinite 

3.229 4.265 

Infinite Infinite 

94 95 

6/54(0.11) 8/44(0.18) 13/50(0.26) 

P = 0.033 N.S. P = 0.043 

«_ 1.636 2.340 

0.538 0.904 

5.281 6.922 

105 88 100 
___ 

_ _ _ 

_ __ 

45

 

TABLE

TOPOGRAPHY: MORPHOLOGY
 

Lung: Alveolar /Bronchiolar Adenoma or
 

Alveolar/Bronchiolar Carcinoma^
 

P Values0
 

Relative Risk (Control)
 

Lower Limit
 

Upper Limit
 

Weeks to First Observed Tumor
 

Kidney: Tubular-Cell Adenocarcinoma
 

P Values0
 

Relative Risk (Control)
 

Lower Limit
 

Upper Limit
 

Weeks to First Observed Tumor
 

Kidney: Tubular-Cell Adenoma or
 

Tubular-Cell Adenocarcinoma
 

P Values0
 

Relative Risk (Control)
 

Lower Limit
 

Upper Limit
 

Weeks to First Observed Tumor
 

5 (CONTINUED) 

CONTROL
 

12/54(0.22)
 

P = 0.003
 

79
 

0/54(0.00)
 

P = 0.009
 

0/54(0.00)
 

P < 0.001
 

LOW
 

DOSE
 

18/44(0.41)
 

P = 0.038
 

1.841
 

0.946
 

3.666
 

88
 

1/50(0.02)
 

N.S.
 

Infinite
 

0.058
 

Infinite
 

104
 

4/50(0.08)
 

N.S.
 

Infinite
 

0.999
 

Infinite
 

100
 

HIGH
 

DOSE
 

25/50(0.50)
 

P = 0.003
 

2.250
 

1.236
 

4.274
 

54
 

5/49(0.10)
 

P = 0.022
 

Infinite
 

1.388
 

Infinite
 

98
 

14/49(0.29)
 

P < 0.001
 

Infinite
 

4.798
 

Infinite
 

98
 
___ 

___ 

46

 

TOPOGRAPHY: MORPHOLOGY
 

Hematopoietic System: Malignant
 

Lymphoma
 

P Values0
 

Relative Risk (Control)
 

Lower Limit
 

Upper Limit
 

Weeks to First Observed Tumor
 

Liver: Hepatocellular Carcinoma
 

P Values0
 

Relative Risk (Control)
 

Lower Limit
 

Upper Limit
 

Weeks to First Observed Tumor
 

Liver: Hepatocellular Adenoma or
 

Hepatocellular Carcinoma"3
 

P Values0
 

Relative Risk (Control)
 

Lower Limit
 

Upper Limit
 

Weeks to First Observed Tumor
 

TABLE 5 (CONTINUED)
 

CONTROL
 

4/55(0.07)
 

N.S.
 

105
 

24/54(0.44)
 

N.S.
 

53
 

28/54(0.52)
 

N.S.
 

53
 

LOW
 

DOSE
 

5/50(0.10)
 

N.S.
 

1.375
 

0.314
 

6.559
 

91
 

20/49(0.41)
 

N.S.
 

0.918
 

0.557
 

1.495
 

92
 

31/49(0.63)
 

N.S.
 

1.220
 

0.846
 

1.737
 

92
 

HIGH
 

DOSE
 

4/50(0.08)
 

N.S.
 

1.110
 

0.214
 

5.600
 

104
 

19/49(0.39)
 

N.S.
 

0.872
 

0.522
 

1.436
 

95
 

23/49(0.47)
 

N.S.
 

0.905
 

0.587
 

1.384
 

95
 
47

 

TABLE 5 (CONCLUDED)
 

TOPOGRAPHY : MORPHOLOGY CONTROL 

LOW 

DOSE 

HIGH 

DOSE 

Circulatory System: Hemangioma 1/55(0.02) 3/49(0.06) 0/50(0.00) 

P Values0 N.S. N.S. N.S. 

Relative Risk (Control) 

Lower Limit 

Upper Limit 

3.367 

0.281 

173.066 

0.000 

0.000 

20.522 

Weeks to First Observed Tumor 105 104 

Treated groups received time-weighted average doses of 500 or 1000 ppm in feed.
 

D

Number of tumor-bearing animals/number of animals examined at site (proportion).
 

"The probability level for the Cochran-Armitage test is given beneath the incidence of tumors in
 

the control group when P < 0.05; otherwise, not significant (N.S.) is indicated. The probability
 

level for the Fisher exact test for the comparison of a treated group with the control group is
 

given beneath the incidence of tumors in the treated group when P < 0.05; otherwise, not significant (N.S.) is indicated. For both Cochran-Armitage and Fisher exact tests a negative designation (N) indicates a lower incidence in the treated group(s) than in the control group.
 

The 95% confidence interval on the relative risk of the treated group to the control group.
 
TABLE 6
 

ANALYSES OF THE INCIDENCE OF PRIMARY TUMORS AT
 

SPECIFIC SITES IN FEMALE MICE TREATED WITH TBPa
 

TOPOGRAPHY: MORPHOLOGY
 

Stomach: Squamous-Cell Carcinoma
 

P Values0
 

Relative Risk (Control)
 

Lower Limit
 

Upper Limit
 

Weeks to First Observed Tumor
 

LOW HIGH 

CONTROL DOSE DOSE 

0/53(0.00) 4/48(0.08) 4/44(0.09) 

P = 0.038 P = 0.048 P = 0.039 

Infinite Infinite 

1.023 1.116 

Infinite Infinite 

96 104 

48

 

Stomach: Squamous-Cell Papilloma or
 

Squamous-Cell Carcinoma
 

P Values0
 

Relative Risk (Control)
 

Lower Limit
 

Upper Limit
 

Weeks to First Observed Tumor
 

Lung: Alveolar /Bronchiolar Carcinoma
 

P Values0
 

Relative Risk (Control)
 

Lower Limit
 

Upper Limit
 

Weeks to First Observed Tumor
 

2/53(0.04)
 

P < 0.001
 

105
 

1/55(0.02)
 

N.S.
 

105
 

14/48(0.29)
 

P < 0.001
 

7.729
 

1.908
 

66.800
 

92
 

1/50(0.02)
 

N.S.
 

1.100
 

0.014
 

84.647
 

104
 

22/44(0.50)
 

P < 0.001
 

13.250
 

3.552
 

108.262
 

102
 

3/50(0.06)
 

N.S.
 

3.300
 

0.273
 

169.657
 

104
 
___ 

49

 

TOPOGRAPHY: MORPHOLOGY
 

Lung: Alveolar/Bronchiolar Adenoma
 

or Alveolar/Bronchiolar Carcinoma*3
 

P Values0
 

Relative Risk (Control)
 

Lower Limit
 

Upper Limit
 

Weeks to First Observed Tumor
 

Hematopoietic System: Malignant
 

Lymphomab
 

P Values0
 

Relative Risk (Control)
 

Lower Limit
 

Upper Limit
 

Weeks to First Observed Tumor
 

Hematopoietic System: Malignant
 

Lymphoma or Leukemia^
 

P Values0
 

Relative Risk (Control)
 

Lower Limit
 

Upper Limit
 

Weeks to First Observed Tumor
 

TABLE 6 (CONTINUED) 

CONTROL
 

4/55(0.07)
 

P = 0.001
 

105
 

14/55(0.25)
 

N.S.
 

86
 

18/55(0.33)
 

N.S.
 

__—
 

86
 

LOW
 

DOSE
 

9/50(0.18)
 

N.S.
 

2.475
 

0.741
 

10.349
 

83
 

14/50(0.28)
 

N.S.
 

1.100
 

0.540
 

2.228
 

92
 

15/50(0.30)
 

N.S.
 

0.917
 

0.484
 

1.706
 

85
 

HIGH
 

DOSE
 

17/50(0.34)
 

P < 0.001
 

4.675
 

1.659
 

17.743
 

104
 

10/50(0.20)
 

N.S.
 

0.786
 

0.345
 

1.718
 

91
 

10/50(0.20)
 

N.S.
 

0.611
 

0.279
 

1.254
 

91
 
___ 

50

 

TOPOGRAPHY: MORPHOLOGY
 

Liver: Hepatocellular Carcinoma
 

P Values0
 

Relative Risk (Control)
 

Lower Limit
 

Upper Limit
 

Weeks to First Observed Tumor
 

Liver: Hepatocellular Adenoma or
 

Hepatocellular Carcinoma*3
 

P Values0
 

Relative Risk (Control)
 

Lower Limit
 

Upper Limit
 

Weeks to First Observed Tumor
 

Circulatory System: Hemangioma
 

P Values0
 

Relative Risk (Control)
 

Lower Limit
 

Upper Limit
 

Weeks to First Observed Tumor
 

TABLE 6 (CONTINUED)
 

CONTROL
 

7/54(0.13)
 

P = 0.001
 

101
 

11/54(0.20)
 

P < 0.001
 

59
 

3/55(0.02)
 

N.S.
 

82
 

LOW
 

DOSE
 

12/50(0.24)
 

N.S.
 

1.851
 

0.732
 

5.101
 

98
 

23/50(0.46)
 

P = 0.005
 

2.258
 

1.193
 

4.508
 

98
 

6/50(0.12)
 

N.S.
 

2.200
 

0.497
 

12.953
 

104
 

HIGH
 

DOSE
 

20/49(0.41)
 

P = 0.001
 

3.149
 

1.421
 

7.932
 

85
 

35/49(0.71)
 

P < 0.001
 

3.506
 

2.030
 

6.236
 

85
 

6/50(0.12)
 

N.S.
 

2.200
 

0.497
 

12.952
 

43
 
___ 

___ 

___ 

51

 

TOPOGRAPHY: MORPHOLOGY
 

Subcutaneous Tissue: Fibrosarcoma
 

P Values0
 

Departure from Linear Trend
 

Relative Risk (Control)
 

Lower Limit
 

Upper Limit
 

Weeks to First Observed Tumor
 

Uterus: Endometrial Stromal Polyp
 

P Values0
 

Q
 

Departure from Linear Trend
 

Relative Risk (Control)
 

Lower Limit
 

Upper Limit
 

Weeks to First Observed Tumor
 

Harderian Gland: Cystadenoma NOS
 

P Values
 

Departure from Linear Trend
 

Relative Risk (Control)
 

Lower Limit
 

Upper Limit
 

Weeks to First Observed Tumor
 

TABLE 6 (CONTINUED)
 

CONTROL
 

0/55(0.00)
 

N.S.
 

P = 0.012
 

0/54(0.00)
 

N.S.
 

P = 0.009
 

0/55(0.00)
 

N.S.
 

P = 0.012
 

LOW
 

DOSE
 

3/50(0.06)
 

N.S.
 

Infinite
 

0.660
 

Infinite
 

83
 

6/49(0.12)
 

P = 0.010
 

Infinite
 

1.760
 

Infinite
 

99
 

3/50(0.06)
 

N.S.
 

Infinite
 

0.660
 

Infinite
 

98
 

HIGH
 

DOSE
 

0/50(0.00)
 

N.S.
 

2/46(0.04)
 

N.S.
 

Infinite
 

0.347
 

Infinite
 

104
 

0/50(0.00)
 

N.S.
 
52 

TABLE 6 (CONCLUDED)
 

LOW HIGH 

TOPOGRAPHY: MORPHOLOGY CONTROL DOSE DOSE 

Kidney: Tubular-Cell Adenoma 0/55(0.00) 2/50(0.04) 2/46(0.04) 

P Values0 N.S. N.S. N.S. ___ Relative Risk (Control) Infinite Infinite 

Lower Limit 0.325 0.353 

Upper Limit Infinite Infinite 

Weeks to First Observed Tumor 85 104 

"Treated groups received time-weighted average doses of 500 or 1000 ppm in feed.
 

Number of tumor-bearing animals/number of animals examined at site (proportion).
 Q
 

The probability level for the Cochran-Armitage test is given beneath the incidence of tumors in
 

the control group when P < 0.05; otherwise, not significant (N.S.) is indicated. The probability
 

level for the Fisher exact test for the comparison of a treated group with the control group is
 

given beneath the incidence of tumors in the treated group when P < 0.05; otherwise, not significant (N.S.) is indicated. For both Cochran-Armitage and Fisher exact tests a negative designation (N) indicates a lower incidence in the treated group(s) than in the control group.
 

The probability level of the test for departure from linear trend is given beneath the control
 

group when P < 0.05.
 
A high incidence of stomach tumors was noted in both male and
 

female dosed mice. Statistical tests were performed combining the
 

incidences of squamous-cell papillomas and squamous-cell carcinomas,
 

so that the measurement of interest was the proportion of mice having
 

either the papilloma or the carcinoma or both. The Cochran-Armitage
 

test indicated a significant (P < 0.001) positive association between
 

the incidence of either squamous-cell papillomas or squamous-cell
 

carcinomas and TBP dosage in both sexes. Fisher exact tests confirmed
 

these results in both sexes by indicating significance (P < 0.001)
 

in comparisons of either the low dose or the high dose groups to the
 

control groups. The spontaneous tumor rates observed in the controls
 

were not significantly different from the 2/625 in males and 6/575 in
 

females observed in the historical control B6C3F1 mice as compiled to
 

date for the NCI Carcinogenesis Testing Program at Mason Research
 

Institute. Based upon these results there was a significant positive
 

association between the administration of TBP under the conditions of
 

this experiment and an elevated incidence of stomach tumors (squamouscell carcinomas and papillomas) in both male and female B6C3F1 mice.
 

For both sexes the dosed mice exhibited a high incidence of lung
 

tumors. Statistical tests were performed combining the incidences of
 

alveolar/bronchiolar adenomas and alveolar/bronchiolar carcinomas, so
 

that the measurement of interest was the proportion of mice having
 

either the adenoma or the carcinoma or both. The Cochran-Armitage
 

test indicated a positive association between TBP dosage and the
 

53
 
incidence of alveolar/bronchiolar neoplasms in both male (P = 0.003)
 

and female (P = 0.001) mice. Fisher exact tests showed a significant
 

difference between the control groups and the high dose groups for
 

both male (P = 0.003) and female (P < 0.001) mice. For the male mice
 

the comparison between the control group and the low dose group had a
 

probability level of P = 0.038, a marginal result which was not significant under the Bonferroni inequality. The spontaneous tumor rates
 

for the combination of alveolar/bronchiolar carcinomas and alveolar/
 

bronchiolar adenomas observed in the controls were not significantly
 

different from the 21/575 (4 percent) observed in female historical
 

control B6C3F1 mice at Mason Research Institute for the NCI Carcinogenesis Testing Program, but they were significantly (P < 0.05) higher
 

than the 70/625 (11 percent) observed in the historical control males.
 

Based upon these results there was a positive association between the
 

administration of TBP and an elevated incidence of lung tumors in both
 

male and female mice under the conditions of this experiment.
 

A high incidence of liver tumors was noted in dosed female mice.
 

When incidences were combined so that the numerator represented mice
 

having either a hepatocellular carcinoma or a hepatocellular adenoma
 

the Cochran-Armitage test indicated a highly significant (P < 0.001)
 

positive association between dosage and the incidence of hepatocellular carcinomas or adenomas. Fisher exact tests confirmed these
 

results in comparing the control group to either the low dose (P =
 

0.005) or the high dose (P < 0.001) group. The spontaneous tumor
 

54
 
rate observed in the control (11/54 or 20 percent) was significantly
 

(P < 0.05) higher than the incidence (29/575 or 5 percent) observed
 

in the female historical controls. Based upon these results there
 

was a significant positive association between the administration of
 

TBP and an elevated incidence of liver tumors in female mice under
 

the conditions of this experiment.
 

In male mice there was a high incidence of kidney tumors. When
 

incidences were combined so that the numerator represented mice with
 

either a tubular-cell adenoma or a tubular-cell adenocarcinoma, the
 

Cochran-Armitage test indicated a significant (P < 0.001) positive
 

association between dosage and incidence. The Fisher exact tests confirmed this relationship with the significant (P < 0.001) comparison
 

of high dose to control group. The spontaneous tumor rate observed
 

in the control group was not significantly different from the 0/625
 

observed in the historical control B6C3F1 male mice. When only
 

tubular-cell adenocarcinomas were considered, again both the Cochran-


Armitage test (P = 0.009) and the Fisher exact test comparing high
 

dose to control (P = 0.022) were significant. Based upon these results there was a significant positive association between the administration of TBP and an elevated incidence of kidney tumors in male
 

mice under the conditions of this experiment.
 

In female mice the Fisher exact test showed a significantly (P =
 

0.010) higher incidence of endometrial stromal polyps in the low dose
 

group than in the control group. No other statistical tests were significant, however.
 

55
 
V. DISCUSSION
 

In both species adequate numbers of animals in all groups survived long enough to be at risk from late-developing tumors. The
 

similarity of mean group body weights for control rats and dosed rats
 

throughout this bioassay indicates that feeding of TBP did not interfere with the growth of rats. Dose-related depression of mean group
 

body weights was, however, observed among mice.
 

Renal tubular-cell adenomas were observed in 48 percent (26/54)
 

of the low dose male rats, 48 percent (26/54) of the high dose male
 

rats, 7 percent (4/54) of the low dose female rats, and 19 percent
 

(10/54) of the high dose female rats. Renal tubular-cell adenocarcinomas were observed only in 6 percent (3/54) of high dose male
 

rats. No neoplasms were observed in kidneys of control rats. There
 

was a significant positive association between the incidence of renal
 

tubular-cell adenomas in female rats and dietary concentration of
 

TBP. In addition, the incidence of tubular-cell adenomas in high
 

dose female rats was significantly higher than that in controls. For
 

male rats, the combined incidence of renal tubular-cell adenomas and
 

renal tubular-cell adenocarcinomas was significant by all statistical
 

tests applied.
 

The incidence of renal tubular-cell adenocarcinomas in low and
 

high dose male mice was 2 percent (1/50) and 10 percent (5/49), respectively, as compared to none in the control group. This indicated
 

a significant positive trend and a significant increase at the high
 

56
 
dose level. No renal tubular-cell adenocarcinomas were observed in
 

female mice. The incidences of renal tubular-cell adenoma in low and
 

high dose males were 6 percent (3/50) and 18 percent (9/49), respectively, as compared to none in the control group. This also indicated a significant positive trend and a significant increase at the
 

high dose level. In the females, renal tubular-cell adenoma occurred
 

in 4 percent of each treated group (2/50 low dose and 2/46 high dose),
 

as compared to none in the control group, but this incidence was not
 

statistically significant.
 

Either squamous-cell papillomas or squamous-cell carcinomas of
 

the forestomach occurred in low and high dose mice, respectively, in
 

21 percent (10/48) and 27 percent (13/48) of the male and 29 percent
 

(14/48) and 50 percent (22/44) of the female mice, as compared to
 

none in the male control and 4 percent in the female control group.
 

This indicated a highly significant positive trend and a highly significant increase of this tumor in both sexes at both dose levels.
 

These tumors were combined for purposes of statistical analysis since
 

they may have a common pathogenesis. Most of the observed squamouscell tumors of the forestomach, however, were interpreted as benign.
 

The incidence of squamous-cell carcinoma of the forestomach in low
 

and high dose females was 8 percent (4/48) and 9 percent (4/44), respectively, as compared to none in the control group. This indicated a
 

significant positive trend, and suggests a relationship to TBP administration. In the males, squamous-cell carcinoma occurred only in 4
 

57
 
percent (2/48) of the high dose group; this incidence was not statistically significant. The incidences of squamous-cell papillomas and
 

squamous-cell carcinomas are suggestive of carcinogenicity because
 

squamous-cell carcinomas of the forestomach rarely occur spontaneously.
 

A high incidence of liver tumors was observed in female mice
 

treated with TBP. The proportion of female mice having hepatocellular
 

carcinomas or adenomas or both was significantly higher in treated
 

groups than control groups for all statistical tests applied. When
 

only hepatocellular adenomas were considered, once again all tests
 

were significant. When only the incidence of hepatocellular carcinomas was considered, the positive dose-related trend was significant
 

and tumor incidence in the high dose group was significantly higher
 

than in the control group. Tumor incidence among male mice was not
 

significant for hepatocellular carcinoma or adenoma.
 

A high incidence of lung tumors was apparent in both male and
 

female mice. The proportion of mice of each sex having alveolar/
 

bronchiolar adenoma or carcinoma or both exhibited a statistically
 

significant positive association with increased dietary concentration
 

of TBP. The incidence of alveolar/bronchiolar carcinomas alone exhibited a significant positive dose-related trend for males, but not
 

for females.
 

1,2-Dibromo-3-chloropropane (DBCP) is a common contaminant of
 

TBP (Kerst, 1974). In a bioassay conducted for the NCI Carcinogenesis Testing Program at Hazleton Laboratories America, Inc., Vienna,
 

58
 
Virginia, DBCP administered by gavage was found to cause a high incidence of squamous-cell carcinomas of the forestomach in rats and mice
 

and also caused a significant increase in the incidence of adenocarcinomas of the mammary gland in female rats. DBCP also caused toxic
 

nephropathy in both rats and mice. Levels of DBCP in the batch of
 

TBP used for this bioassay did not exceed 100 ppm. Although the combined incidences of squamous-cell carcinomas and squamous-cell papillomas of the forestomach were significant in male and female mice,
 

other DBCP-related lesions were not observed at increased incidences
 

in TBP-dosed animals. The incidences of squamous-cell carcinomas of
 

the forestomach in male and female rats and the incidence of mammary
 

adenocarcinomas in female rats did not exceed those in controls.
 

Toxic nephropathy was not reported in rats or mice in this bioassay,
 

although dysplastic lesions were observed in kidneys of TBP-treated
 

rats. The types of dysplastic lesions found in the TBP bioassay were
 

not observed in DBCP-treated rats or mice. It is concluded that the
 

results of this bioassay are due principally to TBP administration.
 

The ability of TBP to induce base-pair substitution mutations
 

in histidine-requiring strains of Salmonella typhimurium supports the
 

positive findings of this bioassay. TBP gave positive Ames test results both with and without activation by hepatic microsomes derived
 

from Spraque-Dawley rats, indicating that TBP can behave as a direct-


acting mutagen (Prival et al., 1977). The mutagenicity of TBP was,
 

however, enhanced by metabolic activation. Prival et al. (1977)
 

59
 
found no significant quantitative differences in mutagenicity among
 

nine different commercial samples of TBP obtained from five different
 

suppliers. These samples included both HV (high in volatiles) and
 

LV (low in volatiles) grades. A highly purified sample of TBP had
 

approximately the same mutagenic activity as the commercial samples
 

(Prival et al., 1977). The authors concluded that it was highly
 

unlikely that the mutagenicity of TBP was due to the presence of an
 

impurity (Prival et al., 1977).
 

It is concluded that under the conditions of this study orally
 

administered TBP was carcinogenic to B6C3F1 mice, causing increased
 

incidences of neoplasms in livers, lungs, and stomachs of female mice
 

and in kidneys, lungs and stomachs of male mice. TBP was also carcinogenic in Fischer 344 rats, causing an increased incidence of kidney
 

tumors in male and female animals.
 

60
 
VI. BIBLIOGRAPHY
 

Armitage, P., Statistical Methods in Medical Research, Chapter 14.
 

J. Wiley & Sons, New York, 1971.
 

Berenblum, I., editor, Carcinogenicity Testing. International Union
 

Against Cancer, Technical Report Series, Vol. 2. International
 

Union Against Cancer, Geneva, 1969.
 

Brieger, H., K. Gabriel, and F. Reiders, "Toxicology and Safe Utilization of Flame Retardants." Paper presented at the American Industrial Hygiene Conference, St. Louis, Missouri, May 15, 1968.
 

Chemical Abstracts Service. The Chemical Abstracts Service (CAS)
 

Ninth Collective Index, Volumes 76-85, 1972-1976. American
 

Chemical Society, Washington, B.C., 1977.
 

Cox, D.R., Analysis of Binary Data, Chapters 4 and 5. Methuen and
 

Co., Ltd., London, 1970.
 

Cox, D.R., "Regression Models and Life-Tables." Journal of the Royal
 

Statistical Society, Series "B" 34:187-220, 1972.
 

Daniher, F.A., "Studies on the Bioavailability of Tris (2,3-dibromopropyl) phosphate from Treated Textiles." Presented at the
 

Tenth Annual Meeting of the ICFF, New York, New York, December
 

10, 1976.
 

Gart, J.J., "The Comparison of Proportions: A Review of Significance
 

Tests, Confidence Limits, and Adjustments for Stratification."
 

International Statistical Institute Review 39:148-169, 1971.
 

Kaplan, E.L., and P. Meier, "Nonparametric Estimation from Incomplete
 

Observations." Journal of the American Statistical Association
 

_53_:457-481, 1958.
 

Kerst, A.F., "Toxicology of Tris (2,3-dibromopropyl) Phosphate."
 

Journal of Fire and Flammability/Fire Retardant Chemistry Supplement 1:205-217, 1974.
 

Linhart, M.S., J.A. Cooper, R.L. Martin, N.P. Page, and J.A. Peters,
 

"Carcinogenesis Bioassay Data System." Computers and Biomedical
 

Research 7:230-248, 1974.
 

Miller, R.G., Simultaneous Statistical Inference. McGraw-Hill Book
 

Co., New York, 1966.
 

61
 
Morrow, R.W., C.S. Hornberger, A.M. Kligman, and H.I. Maibach, "Tris
 

(2,3-dibromopropyl) Phosphate: Human Contact Sensitization."
 

American Industrial Hygiene Association Journal 37:192-197, 1976.
 

Osterburg, R., Memorandum from Consumer Products Safety Commission to
 

U.S. Environmental Protection Agency, Office of Toxic Substances,
 

January 1976.
 

Prival, M.J., E.G. McCoy, B. Gutter, and H.S. Rokinkronz, "Tris (2,3­

dibromopropyl) Phosphate: Mutagenicity of a Widely Used Flame
 

Retardant." Science 195:76-78, 1977.
 

Saffiotti, U., R. Montesano, A.R. Sellakumar, F. Cefis, and D.G.
 

Kaufman, "Respiratory Tract Carcinogenesis in Hamsters Induced
 

by Different Numbers of Administration of Benzo (a) Pyrene and
 

Ferric Oxide." Cancer Research 32:1073-1079, 1972.
 

Simpson, R.O., Chairman, Consumer Product Safety Commission. Letter
 

to The Honorable Warren G. Magnuson, Chairman, Committee on Commerce, U.S. Senate, Washington, B.C., April 1976.
 

Stich, H.F., Personal Communication to the Environmental Defense Fund
 

from the University of British Columbia. October 4, 1976.
 

St. John, L.E.H., M.E. Eldefrarvi, and D.J. Lisk, "Studies of Possible
 

Absorption of a Flame Retardant from Treated Fabrics Worn by Rats
 

and Humans." Bulletin of Environmental Contamination and Toxicology 15:192-197, 1976.
 

Tarone, R.E., "Tests for Trend in Life-Table Analysis." Biometrika
 

62:679-682, 1975.
 

62
 
APPENDIX A
 

SUMMARY OF THE INCIDENCE OF NEOPLASMS
 

IN RATS TREATED WITH TBP
 

TABLE Al

 

SUMMARY OF THE INCIDENCE OF NEOPLASMS IN MALE RATS TREATED WITH TBP 

c:ONTEOL (UNTR ) LOW COSE 

01-0360 01 -0405 

AM1!AI c c; S INITIALL Y I N STUD Y 55 

ANIMAI S KECRCESIE D 5a 55 

ANIMAL S EXAMINE D HISTOPATHOLOG ICA I1Y *¥ su 55 

INTEGUMENTAR Y SYSTE M 

*SKI N (5«) (55) 

SCUAMCU S CELL EAEILLOM A 2 (H%) 

BIEECB A 2 (4% ) 

*SUECU T TISSUE (5U) (55) 

FIBBCM A 2 (4») 1 (2%) 

FIEKOSARCOH A 2 (UX ) 

RESPIFATCR Y SYSTE M 

#LUN G (54) (55) 

ALVECLAB/EECNCHIOLA B ADENOM A 2 (4%) 

fLVEOLJR/ERONCRIOLA H CARCINOMA 1 (2%) 

PHEOCHROMOCYTOMA , METASTATIC 

OSTEOSJRCOMA , HETASTATIC 

HE»ATCECIETI C SYSTE M 

*MULTIPL E ORGAN S (5U) (55) 

ITAIIGNAN T LYMEHCMA , NO S 1 (2%) 

CNDIFFERENTIATE D LEUKEMI A 

LYMPHOCYTI C LEUKEMI A 

13 (2«X ) a (1%) 

12 (22%) 

1 (2%) 

ttiEDIASIINA L L.NOC E 

AIVECLAE/BBCNCHIOLA E CA, METAST A 

(53) (51) 

1 (2%) 

EHEOCHROMOCYTOMA , METASTATIC 

CIRCniATCE Y SYSTE M 

#HEAE T (5t) (55) 

IHffiCHISjHiCYTSMii.aiT^STiTIC.. 

# NUCBE R CF ANIMAL S WITH TISSUE EXAMINE D MICROSCOPICALLY 

* NUKBE E CE ANIMAL S NECEOPSIE D 

**EXCLUDES PARTIALLY AUTOLYZED ANIMALS 

HIG H DOSE 

01-0410 

c c 

55 

55 

(55) 

2 (4X) 

(55) 

1 (2%) 

(55) 

1 (2%) 

1 (2X) 

(55) 

6 (11SJ 

1 (2X) 

(51) 

1 (2X) 

(55) 

J.122L. 

A-3 
TABLE A1 (CONTINUED) 

EIGES1IV E SYSTE M 

#SALIVAR Y GLAN D 

ACINAE-CEL L AEENCM A 

tllVE E 

NECELASTI C NOCUL E 

HEPATOCELLULA R CARCINOM A 

*BILE EUCT 

BUI rOCT CARCINOM A 

SS10MAC H 

SCUAFCU S CELL EAEILLOM A 

SgOAMOU S CELL CARCINOM A 

EASAL-CELL CARCINOM A 

tJEJDNU K 

FTJCINCU S ACENOCAHCINOM A 

URINAR Y SYSTE H 

HKIDNE Y 

TUEUIAE-CEL L AEENOM A 

1LEDLAR-CEL L AD5NOCARCI NOM A 

tUEIhAB Y BLAEEE R 

TEANSITICNAL-CEL L EAPILLOMA 

ENECCRIN E SYSTE M 

tPITLIIAR Y 

CAECINCBA , NOS 

ADENOMA , NO S 

CHROMOPHOE E ADENOM A 

CHROMOPHOBE CARCINOM A 

ACIDOPHI L ADENOM A 

EASOPBI L ADENOM A 

#ADEENA I 

CCE1ICAL AEENCM A 

PEECChHCMCCYTCM A 

PiJlCCHRCMCCYTCHAi-BAIISNOl 

# NUBBE 5 CF ANIMAL S HITH TISSU E

* hUMBE E CE ANIMAL S NECEOPSIE D 

CONTROL (UNTR)

01-0360

(50 ) 

(54) 

(54) 

(53) 

2 (4% ) 

(52) 

(53) 

(51) 

(46) 

4 (8%) 

1 (2% ) 

(54) 

1 (2%) 

12 (22% ) 

1 1W 

 IOW DCSE 

 01-0105 

(53) 

1 <2») 

(55) 

1 (2X) 

(55) 

(54) 

2 (4«) 

1 (2%) 

1 (2X) 

(53) 

1 (2%) 

(54) 

26 (48%) 

(51) 

1 (2%) 

(50) 

1 (2«) 

1 (2%) 

7 (14S) 

1 (2%) 

3 (6«) 

(55) 

6 (15% ) 

J_J5£1_. 

 EXAMINE E BICROSCOPICAILY 

HIGH DOSE 

01-0410 

(54) 

1 (2% ) 

(54) 

2 (4%) 

2 (4%) 

(55) 

1 (2%) 

(52) 

1 (2%) 

(51) 

(54) 

26 (48%) 

3 (6%) 

(49) 

(50) 

3 (6%) 

2 (4% ) 

(55) 

13 (24%) 

3_J5%1_. 

A-4 
TABLE Al (CONTINUED) 

CONTROL (UNTR) ICH DCSE 

01-0360 01-0405 

*THYBCII (53) (51) 

fCIIICULAB-CILL CABCINOM A 

C-CELI ADENOM A 3 (6X) 2 (4%) 

C-CELL CARCINOMA 1 (2X) 

tEABCBEATIC ISLE1S (53) (53) 

ISIIT-CELL AEENCH A 1 (2%) 3 (6») 

ISLET-CELL CARCINOM A 1 (/%} 

REPRCEUCTIV E SYSTE M 

*MAMMAR Y GLAN D (5U) (55)

 

ADE^KA , NCS 

INTRADOCTA L PAPILLOM A 1 (2% ) 

FIEROADENOM A 1 (2% ) 

*EBE£iniAI GLAN E <5U ) (55) 

CABCIKMA,NO S 1 (2% ) 2 (4X) 

ADENOMA , NOS 1 (2%) 

ADENOCARCINOM A , NOS 

*TES1IS <5U) (55) 

INTEESTITIAL-CELL TUMOR 53 (98») 46 (84X) 

NERVCU S SYSTEH 

#EFAI K (54) (55) 

CEBOHINCU S CARCINOMA , HETAS1ATI C 1 (2%) 

AS1ROCYTOMA 

SPECIA L SE^S E CBGAN S 

*EYE (5H) (55)

 

SQUAMCO S CELL CABCINOM A 1 (2%) 

*EA B (54) (55)

 

CIROKISCU S CABCINOM A 1 (2X) 

*EA B CANA L (54) (55) 

StBACECU S ADENOCABCINOM A 1 |2*) 

££EJS«JBQU5 fi&SCjNQM . J_Ii31__ . 

* NUKBE B CF ANIMAL S BITH TISSU E EXAMINE E MICROSCOPICAIIY 

* NOMBE E OJ ANIMAL S NECEOPSIED 

HIGH DCSE 

01-0410 

(52) 

2 (4») 

3 (6») 

1 (2%) 

(51) 

1 (255) 

1 (2%) 

(55) 

1 (2X) 

1 (2%) 

(55) 

3 (5%) 

3 (5X) 

1 (2») 

(55) 

50 (91X) 

(55) 

1 <2X ) 

(55) 

(55) 

(55) 

A-5 
TABLE A1 (CONTINUED)
 

HIGH DCSE 

01-0410 

(55) 

1 <2X ) 

(£5 ) 

(55) 

1 (2%) 

(55) 

(55) 

(55) 

(55) 

1 (2X) 

(55) 

1 (2«) 

(55) 

1 

«.«. __. «..____ 

MUSCOICSKEIEIA L SYSTE M 

*SKCLL 

CSTECSABCOM A 

*HAMIBIE 

CSTICSABCCM A 

*STEHNUM 

EHECCHFCKCCY1CBA , BETAS! ATIC 

*EIB 

AIVECIAR/BRCNCHICLA B CA, HE1AS1A 

BOE Y CAVITIE S 

*AEDOHINA L CAVIT Y 

FESCTHELIOBA , NO S 

*PEEITCKEU B 

KISCTHELICBA , NO S 

*PELVI S 

CHCEECK A 

*HESENTEE Y 

EIBBCSARCCB A 

A l t C1HEE SYSTEM S 

*MUL1IPLE ORGAN S 

1ES01HELIOMA, NOS 

DIAEHEAG B 

f 1BECSARCCHA , BE1ASTATIC 

OMINTU M 

^ ^-IIBKiAJSfiUA--^ ^ -, „. 

CONTROL (UNTR) L OW DCSE 

0 1-0360 01-0405 

(54) (55) 

(5U) (55) 

1 (2% ) 

(5U) (55) 

(54) (55) 

1 <2X ) 

(5<4 ) (55) 

1 (2%) 

(54) (55) 

1 (2%) 

(54) (55) 

(54) (55) 

1 (2%) 

(54) (55)

 

2 (H%) 

1 

#	 NCBEER OF ANIMALS WITH TISSUE EXAMINED BIGEOSCOPICALLY
 

* NUFBE E CI ANIMALS NECFOPSIED
 

A-6 
TABLE Al (CONCLUDED) 

CONTROL (UNTR ;| IOH DCSE

0 1-0360 01-0405

ANIMA L DISPOSITION SUMMAR Y 

AMfAl S INITIALLY IN STUC Y 55 55

NATUBA L CEATH3 6 3

MOBIEUN E SACRIFICE 1 0 17

SCHIEULE t SACEIFICE 

ACCIIEKTALLY KILLED 

TERMINA L SACEIFICE 39 35

ANIfA I HISSIN G 

3 INCLCDE S AUTOLYZE D ANIMAL S 

TUPC E SUKKAE Y 

TOTAL AMMAL S WITH EPIMAR Y TUMORS* 54 54

TOTA L PRIMAR Y TUMCE S 112 138

TOTA L ANIMAL S WIT H BENIG N TUHCR S 5 3 51

TOTA L EENIG N TUMORS 63 104

TCTA L AMMAL S HU H MALIGNAN T TUMOR S 2 6 26

TCTA L CALIGNAN T TUMOR S 2 7 ^ 2

TOTACL AMHAL S WITH SECONDAR SECCNDARYY TUMOES 1UMOES# *1 1

T C T A L SECCNDAE SECCNDAEY TUMOR S 1 2

T C T A I A M H A LA M H A L S W I T H T U M O ET U M O E S UNCEHTAIN UNCEHTAIN -­

E E K I GE E K I GCK CE MALIGNAN E MALIGNAN T 2 T 2 2 2

T O T A L UNCERTAI UNCERTAI N T U M O RT U M O RS 2 2

T C T A L AMMAL S W I T H T U M O ET U M O E S UNCERTAIN UNCERTAIN -­

EEIMAE Y C E MEIASTATI MEIASTATI C 

T C T A L UNCERTAI UKCEETAI N TUMCE S 

* PRIKAR Y TUMCHS : AL L TUMCE S EXCEE T SECCNEAE Y TUMOR S 

f SECCNDAR Y TUMORS : METASTATIC TUMOR S O E TUMOS S INVASIV E INTO A N

 HIGH DCS E 

01-0410 

55 

7 

8 

40 

55 

138 

51 

107 

24 

29 

3

6 

2 2

 

2 2

ADJACEN T ORGA N 

A-7 
TABLE A2

 

SUMMARY OF THE INCIDENCE OF NEOPLASMS IN FEMALE RATS TREATED WITH TBP 

(;ONTROL (UNTfi) IOH DCSE 

02-0360 02-0405 

ANIMAL S INITIALL Y I N STUD Y £5 55 

ANISAIS bECECESIIt 54 55 

ANIBAI S EXAMINE E HI STOFATHOLOGICALL Y ** 54 55 

INTEGUHEK1AE Y SYSTEM 

*SKIN (51) (55) 

SCUABCO S CELL PAPILLOM A 2 <«) 1 (2%) 

SQUAMOU S CELL CARCINOM A 2 («) 1 (2%) 

*SUBCUT 1ISSCE (54) (55) 

fIBRCM A 1 (2%) 1 (2%) 

FIEECSARCCK A 

IIPCB A 2 <4X ) 

LIPOSAECOMA 1 (2%) 

RESEIBATCB Y SYSTEM 

#LCN G (53) (54) 

BILE CUCT CARCINOMA , METASTATI C 

ALVEOLAR/ERONCKIOLA R ADENOM A 1 (2% ) 2 (4%) 

ADENOSQUAMOU S CARCINOM A 1 (2%) 

FIEROSARCOMA , METASTATIC 

HEHATCECIET K SYSTE M 

*MUL-IIPL E ORGAN S (54) (55) 

ONEIFFEBEN1IA1I C LEOKEMI A 8 (15%) 9 (16X) 

LiMPHOCYTI C LEUKEMI A 1 (2X ) 1 (2%) 

tBCN E KABEC H (53) (54) 

PIBFCSAECCMA , METASTATIC 

#SPIEE K (52) (54 ) 

MUECJIBECSABCOMA , UNC PRIM OR M 1 (2%) 

tLYMP H NODE (51) (54) 

mi_IIlCI._CA..BC.IlC.M.AA_M.lT.ASlA.lIC. 

* KOJ!BE E CI ANIMAL S HITH TISSUE EXAMINE D MICROSCO P 1C AllY 

* NUPBE E Cf ANIMAL S NECEOPSIE D 

**EXCLUDES PARTIALLY AUTOLYZED ANIMALS 

HIGH DCSE 

02-0410 

55 

55 

EC 

(55) 

2 (4%) 

(55) 

1 (2%) 

(55) 

1 (2%) 

2 (4%) 

(55) 

9 (1635) 

(52) 

1 (2%) 

(S5 ) 

(54) 

J-J221. 

A-8 
TAB7

,E A2 (CONTINUED) 

HIGH DCSE 

02-0410 

(54) 

(54) 

1 (2X) 

(45) 

1 (2X) 

(55) 

(55) 

2 (4X) 

(55) 

1 (2X) 

(55) 

2 («X) 

(54) 

1 (2*) 

(52) 

1 <2X) 

(54)

_ja.iJ2i 

tMIEIASTIKA L L.NOD Z 

UKriFIERENTIATE D CARCINOM A METAS 

tMESENTERIC L. NODE 

ONCIFFEBENTIATI C CARCINOM A BETAS 

EILE DDCT CARCINOMA, METASTATIC 

tTHYMU S 

THYKCM A 

CIRCUIATCB Y SYSTE M 

tHEAE T 

KEUBCEIBBCSABCOMA , UNC PRIM OR M 

DIGESTIV E SYSTE M 

tSALIVAB Y GLAN D 

AIEKCCA , NO S 

KIKAR-CEL L ADENCM A 

tLIVE B 

NECELASTIC NODDL E 

HEPATOCELLULAR CARCINOMA 

NEDROFIEROSARCOMA , UNC PRI M OR H 

*BILE LUCT 

BIL B CUCT CARCINOM A 

tPANCREA S 

BILE CUCI CARCINOMA, METASTATIC 

tSTCRAC H 

SCUAKOU S CELL EAFILLOMA 

SQUAMCU S CEL L CARCINOM A 

EASAI-CEL I CARCINOM A 

ADENOCARCINOMA , NO S 

URISAE Y SYSTE M 

tKIDNE Y 

TUEUIAB-CE.L.L. A£JNOflA 

c:ONTROL (UNTH) 

02-0360 

(51) 

1 (2%) 

(51) 

1 (2%) 

(42) 

(53) 

1 (2%) 

(52) 

3 (6X) 

(53) 

1 (2X ) 

1 (2X) 

(54) 

(52) 

(51) 

1 (2%) 

1 (2X ) 

1 (2X ) 

(52) 

IOH DCSE 

02-0405 

(54) 

(54) 

(50) 

(54) 

(54) 

(54) 

1 (2*) 

(55) 

(53) 

(54) 

1 (2%) 

1 <2X ) 

(54) 

« JZS1 - ­

f NUHBE E Cf ANIHAL S WITH TISSUE EXAMINE E MICROSCOPICALL Y 

* KURBE B C E ANIMAL S NECBOPSIED 

A-9 
TABLE A2 (CONTINUED) 

ENECCEIN I SYSTE M 

tPntlTAR Y 

OECIKMA.NO S 

ADENOMA , NOS 

CHROMOPHOBE ADENOM A 

CHRONOPHCBE CARCINOM A 

ACIDOPEIL ADENOM A 

EASOPHI L ADENOM A 

tAEEENA L 

CCE-IICAL AEINCH A 

PHECCHROMOCYTOH A 

ANGIOLIPOMA 

*THYECIE' 

UttEIJEEBENTIATE E CAHCINOM A 

ECHIICULAH-CEL L ADENOM A 

C-CEII ADENOM A 

C-CELL CARCINOMA 

•PAKCEEA1IC ISLE1S 

IEIM-CELL AEENCM A 

BEEECCaciID E SYSTE M 

*HA?KAR Y GLAN D 

PAPILLOMATOSIS 

ADENOMA , NO S 

ADENOCARCINOMA , NOS 

FIBROSARCOM A 

FIERO ADENOM A 

*CLITCEA L GLAN E 

CABCISCMA.NO S 

JCE^EA , NCS 

ADENOCAHCINOKA , NCS 

fOTEEU S 

IKEOKETEIA L S1EOMAL POLYP 

ODOMET8IAL STROMAl SARCOMA 

HEMANGIOM A 

#UTEBU£/ENECMETfiIO M

i.CJNCC.A.fieiNCMA.j.-flOS 

# KUHBE B CE ANIMAL S WITH TISSU E

* KDMBE E CE ANIMAL S NECEOPSIED 

CONTROL (ONTR) I0« DCSE 

02-0360 02-0405 

(U6 ) (54) 

3 (6%) 1 (2%) 

1 (2%) 

15 (31X) 22 (41%) 

1 (2% ) 

1 (2X ) 2 (4%) 

(53) (53) 

1 (295) 1 (2%) 

3 (6X) 4 (8X) 

1 (251) 

(49) (53) 

1 (2») 

1 (2X ) 1 (2*) 

3 (6%) 2 (4%) 

(52) (53) 

1 (2X) 

(54) (55) 

1 (2X) 

1 (2%) 

2 (H%) 

16 (3CX ) 10 (18%) 

(54) (55) 

2 (H%) 

3 (5%) 

1 (2%) 

(52) (54) 

16 (31% ) 14 (26%) 

1 (2%) 

2 (4%) 

<52) (54) 

J_Ji%J 

 EXAMINE E MICROSCOPICALL Y 

HIGH DCSE 

02-0410 

(52) 

1 (2%) 

24 (46%) 

1 (2%) 

(54) 

2 (4%) 

2 (4%) 

(53) 

1 (2%) 

4 (8%) 

(54) 

(55) 

2 (4%) 

2 (4%) 

1 (2X) 

19 (35X1 

(55) 

1 (2% ) 

(55) 

11 (20%) 

1 (2%) 

(55) 

_um. 

A-10 
TABLE A2 (CONTINUED)
 

clONTROL (UNTR) ICW 0CSB HIGH DOSE 

02-0360 02-OH05 02-0110 

tCVAB X (53) (53) (55) 

GBANULCSA-CEL L TUMO B 1 (2X) 1 (2X) 

GRANCLOSA-CELL CARCINOMA 1 12%) 

SERTOLI-CEIL TOHOR 3 (5X) 

TCECLA R ADENOM A 2 (US) 

NERVOU S SYSTEM 

• GRAI N (52) (54) (54) 

CABCIliCHA, NOS, METASTATI C 2 (UX ) 

CHROMOPHOBE CARCINOMA , METASTATI 1 (2X ) 

AS1ROCYTOMA 2 (4X) 

SPECIA L SE1.SE CEGAN S 

*EYE (5«) (55) (55)

 

SCOARCD S CELL CABCINOBA 2 («X) 

*EAB CANA L (5«) (55) (55) 

CEROeiKOOS CARCINOMA 1 (2X) 1 (2X) 

RDSCUICSKEIETA L SYSTE M 

NC»E 

BOC Y CAVITIE S 

*PERITONEDM (54) (55) (55) 

KESCTHELIOMA , NO S 2 (4X) 

*P1IOBA (5U) (55) (55) 

BISCTHELICMA , NOS 1 (2%) 

*MESENTER Y (54) (55) (55) 

FIBBCSARCCM A 2 (4%) 

Atl CTHEH SYSTEMS 

*MOITIEIE CBGAN S 15U) (55) (55) _.»_«___._.~_ _

 -AII»C£aBClNCMiJ._NQSt_ME3ASTiII£_ . 1.J121 

* NOBBEB CF ANIMALS HITH TISSUE EXAMINEE MICROSCOPICALLY
 

* NOBBEB CI ANIMALS NECBOPSIED
 

A-ll 
TABLE A2 (CONCLUDED) 

CONTROL (UNTR) LOH DCSE

02-0360 02-0405

ANIMA L DISPOSITION SUMMAR Y 

ASIKAIS INITIALLY IN STUD Y 55 55

 

KATUBA L EEATHd 6 2

 

HOBIECN E SACRIFICE 13 9

 

SCHIEDIEC SACEIFICE 

ACCIEESTALLY KILLED 

TERMINA L SACRIFICE 36 W

 

JNU'AL HISSING 

a INCLUDES AGTOLYZE D ANIMALS 

TUHC E SDKBAB Y 

TCTAI AKIMAL S WITH EEIHAB Y 1UHORS* 52 HI 

TCTAI EBIMAR Y TUHOES 100 S2

 

I01AL ANIMALS HITH BENIGN TUMORS 45 43 

101AL EENIG N TUMORS 61 70

 

TCIAL AMKAL S HU H MALIGNAN T TUMORS 24 19 

1CTAI KALIGNAN T TDMOBS 28 21

 

TCTAI AKIKAL S WITH SECONDARY TUMOES # 5 

TCTAL SECCNDAE Y TUMOBS 6 

TCTA L AK1MAI S WITH TUMORS UNCEB1AINEENIG N C E BALIGNAN T 2 1

 

1OTAL DNCERTAI N TUMOBS 2 1

 

TC1AI AMMAL S WIT H TUMOB S UNCERTAIN -

EflKAB Y C B METASTATIC 1

 

TCTAI UNCEETAI N TUMOBS '­

* PHIKAB Y TUMCBS : ALL TUHOES EXCEET SECCNCAB Y TUMORS 

I SECONDAR Y TUMORS: METASTATIC TUMOR S OE TUMOBS INVASIV E INTO AN

 HIGH DCSE 

 02-0410 

55 

4 

15 

36 

54 

115 

47 

82 

2H 

29 

3 

7 

3 

4 

 ADJACENT ORGA N 

A-12 
APPENDIX B
 

SUMMARY OF THE INCIDENCE OF NEOPLASMS
 

IN MICE TREATED WITH TBP
 

TABLE Bl

 

SUMMARY OF THE INCIDENCE OF NEOPLASMS IN MALE MICE TREATED WITH TBP 

cXNTEO L (UNTR ) LOW EOSE 

C5-0360 05-0415 

ANIKA1 S INITIALL Y I N STUD Y 55 50 

JNIKJUS kECHCESIED 55 50 

ANIMAL S EXAMINE D HISTOPAT HOIOG ICA LLY ** 55 50 

INTIGUKESTAR Y SYSTEM 

*SBIK (55) (50)

 

SCUAHCD S CELL EAFILLOM A 1 <2*}

 

SEEKECU S ADENOM A 

*SUBCU T TISSU E (55) (50)

 

EIBECF.A 2 (4%) 

EIEECSARCCK A 1 (2% ) 2 (4S)

 

RESEIEATCB Y SYSTE M 

*LCN G (51) (44) 

HEFJTCCELLULA E CAECINOMA , METAS T 4 (7% ) 1 (2%)

 

ALVEOLAR/BRONCHIOLA R ADENOM A 6 (11X) 11 (2554) 

ALVEOLAR/BRONCHIOLA R CARCINCM A 6 (11%) 6 (1854) 

HEMATCECIETI C SYSTE M 

*MULTIPL E ORGAN S (55) (50)

 

KALIG.LYMEHOMA , HISTIOCYTIC TYP E 1 (2%)

 

MALIGNAN T LYMPHOMA , MIXED TYPE 2 (45!) 2 (4%)

 

ISElEEl i (51) (47)

 

HEMANGICK A 1 (2%)

 

SAIIC .IYPEHCMA , HISTIOCYTIC TYPE 

KJLIGNAN T LYMEHCMA , MIXED TYPE 1 (2« )

 

#KEDIASTItiA L L.NCC E (U8 ) (43 )

 

EIBFCSAECCMA , METASTATIC 

#KESENTIEI C L . NCC E (48) (43) 

HIEATCCELLULA B CARCINOMA , METAS T 1 (250 1 <2X ) 

M»LIGNMT_LYMPKOMA * "IXEE TYP E 1 12%L_ __ 

# NUMBE E C E ANIMAL S WIT H TISSU E EXAMINE E MICROSCOPICALL Y 

* KUMBE B Cf ANIMAL S NECEOPSIED 

**EXCLUDES PARTIALLY AUTOLYZED ANIMALS 

HIG H DOSE 

05-0420 

50 

50 

50 

(50) 

1 (2«) 

(50) 

1 (2») 

(50) 

1 (2%) 

12 (24S) 

13 (26%) 

(50) 

2 (4X ) 

(49) 

1 (2«) 

(44) 

1 (2%) 

(44) 

- _i-J2Sl_ 

B-3 
TABLE Bl (CONTINUED) 

CONTROL (ONTR) L OW DCSE 

05-0360 05-0415 

ILIVE B (54) (49) 

MAUGNAS T LYNEHCMA , NO S 1 (2%} 

#JEJUliU M <50) (47) 

KAIIGNAN T LYMPHCMA, MIXED TYPE 1 (25!)

 

CIBCUIA1CF Y SYSTE M 

IBEABT (55) (49) 

HEKAKGICH A 1 (2%) 

DIGESTIVE SYSTEM 

*LIVER (54) (49) 

HEPATCCELLULA B ADENOM A 4 (7X) 11 (22%) 

HEPATOCELLULA R CARCINOMA 21 (44« ) 20 (41S) 

4PAKCEEA S (49) (46) 

HEEATCCIILULA F CARCINOMA, MEIAS T 1 (2%) 

ISTCKAC H (51) (47) 

SCUAMCU S CELL PAPILLOBA 10 (21*) 

SQOAMOI S CELL CARCINOMA 

EASAL-CEL L CARCINOM A 

URINAR Y SYSTEK 

*KIEKE Y (54) (50) 

TDBDIAE-CEL L ADENOM A 3 (651) 

TDEDLAR-CEL L ADENOCARCI NOMA 1 (2%) 

f KIE^EY/EELVI S (54) (50) 

TEANSI1ICNAL-CEL L PAPILLOM A 1 (2X )

 

#DEINAR Y ELADDE R (48) (38) 

HEKAKGICM A 2 <5X) 

HEMANGIOSARCOM A 

ENDOCRIN E SYSTE M 

IEITDITAE Y <39 ) (38) 

SBBCBCiasSJ_A£l£QaA J_J3£1 

# NOKBE B CE ANIMAL S WITH TISSU E EXAMINE D MICROSCOPICALL Y 

* KOHBE E CP ANIMAL S NECBOPSIED 

HIGH DCSE 

05-0420 

(49) 

(48) 

(50) 

(49) 

4 (8%) 

19 (395S) 

(49) 

(48) 

11 (23«) 

2 (4S)

 

1 (2«)

 

(49) 

9 (18%) 

5 (10% ) 

(49) 

(47) 

1 (2%) 

(43) 

B-4 
TABLE Bl (CONTINUED) 

CONTROL (DNTR) LOW DOSE HIGH DOSE 

05-0360 05-0415 05-0420 

#AEBENA I (50) C»2) (48) 

CCBTICAL ACENCM A 1 (2X) 1 (2%) 

PHEOCHROMOCYTOM A 1 (2%) 

#ADEENAl/CAESUL E (50) (U2) (48) 

AtENCtA , NOS 5 (10%) 1 (2X)

 

*EANC5EATIC ISLE1S (49) («6) (49)

 

ISm-CELL ACENCM A 2 (H%) 

BBEBCCDC7ID E SYSTE M 

*TESTIS (5K) («J9) (50)

 

INTEESTITIAL-CELL TOHOE 1 (2%) 

NERVCU S SYSTEH 

NCN E 

SPECIAI SE^SE ORGAN S 

*HABEERIA N GLANC (55) (50) (50) 

CYS1ACEKCBA , NO S 1 (2%) 1 (2X) 2 (4%) 

MUSCDICSKILETA L SYSTE M 

NCN E 

EOC Y CAVITIE S 

*MECIASlIkU M (55) (50) (50) 

AIVECLAR/BBCNCHIOLAR CA, ME1ASTA 1 (2%) 

*PEBITCSEU B (55) (50) (50)

 

BISCTHLICHA, NOS 1 J2X) 

All CTHE E SYSTEM S 

*HOL1IPLE ORGAN S (55) (50) (50) 

^2aM21!S_£ELi_CAR£IfiS»A4_HITASTA_ i_J2.*l .•••••.—— •_•—•.•-—.— —­

* NUBBE 8 CE ANIMAL S WIT H TISSUE EXAMINE D MICROSCOPICALL Y 

* KUWBE B CE ANIHALS NECEOPSIED 

B-5 
TABLEB1 (CONCLUDED) 

CONTROL (UNTR) IOW DOSE

05-0360 05-0415

ANIMA L DISPOSITION SUMMARY 

ABIKAI S INITIALL Y I N STUE Y 55 50

NATOBA L CEATH 9 9 7

MOBIEDN C SACRIFICE 2 4

SCHIEOLE E SACEIFICE 

ACCIEEKTALL Y KILLE D 1

 

TERBINA L SACBIflCE < 44 36

JNICA L KISSIN G 

3 INCLUDES AGTOLYZE D ANIMAL S 

TUBC E SOM-ABY 

TCTA L ANIBAL S WIT H EBIMAR Y 10BORS* 43 41

TCTAI FBIBAR Y TDMCE S 59 60

TOTA L ANIMAL S WIT H BENIG N TUHCH S 1 2 25

10TAL EBNIG N TUBORS 2U 43

TCTA I AKIKAL S HIT H MALIGNAN T TUMOR S 29 30

TCTA I PALIGNAN T TUMOB S 35 26

TCTAI AMKAI S WITH SECCNDAB Y TUBOBSt a 2

TCTA I SECCNDAB Y TUMOBS 5 3

TCTAI AMHAI S WIT H TOBOBS ONCERTAIN ­

EEKIG N C B BAIIGNAN T 1

 

TOTA L CNCERTAI N TUMORS 1

 

TCTA I AMBAL S WIT H TOMOBS UNCERTAIN ­

FIIBAB Y C B METASTATIC 

TCTA I UNCERTAI N TUMOR S 

* PRIMAR Y TOHCBS : AL L TUMOR S EXCEPT SECCNCAR Y TUMORS 

# SECONDAR Y TUBORS: METASTATIC TOMOBS OB TUMOB S INVASIV E INTO

 HIGH DOSE 

 05-0420 

 50 

3 

4 

 43 

 43 

 86 

 28 

 40 

 34 

 46 

4 

4 

 A N ACJACEN T ORGA N 

B-6
 
TABLE B2

 

SUMMARY OF THE INCIDENCE OF NEOPLASMS IN FEMALE MICE TREATED WITH TBP 

CONTROL (ONTH) 10H DCSE 

06-0360 06-OU15 

ANIMAL S INITIALL Y IN STUDY 55 50 

ASIHAI S KECBCESIE E 55 50 

ANIKAI S EXAMINE D HISTO PATHOLOGIC ALLY ** 55 50 

INTBGOHEN'IABY SYSTEM 

*SOECU1 TISSUE (55) (50) 

flEFCSABCOM A 3 (6%) 

HEMANGIONA 1 (255) 

RESPIEATCE Y SYSTE M 

ILCNG 

HEPATCCELLULA B CARCIN

ALVBOLAR/BRONCHIOLAR

ALVEOLAB/BBONCHIOI.AR

OMA , METAS1 

 ADKN08A 

 CARCINOM A 

(55) 

2

3

1

 (14%) 

 (5%) 

(2%) 

(50) 

1

8

1

 (2%) 

 (16X) 

 (2X) 

HEMATCFCIITIC SYSTEM 

+MDL1IPLE ORGAN S (55) (50) 

RALIGNAN I LYHEHCMA , NO S 1 (2%) 

MALIC-. LYMPHOMA , LYMPHOCYTIC TYPE 2 (H%) 1 (2%) 

MALIG.LYMPHOMA , HISTIOCYTIC TYPE 1 (2X) 2 (4X) 

MALIGNAN T LYMPHOMA . MIXED TYPE 6 (11%) if (8X) 

LYMPHOCYTIC LEUKEMIA i« (1%) 1 (2%) 

1SEIEEK (53) (47) 

HIHABGICM A 1 (2%) 

HEMANGIOSARCOM A 2 («*) 

MALIGNAN T LYMPHOMA , MIXED TYPE 1 (2») 3 (6%) 

tlYKI H KCE E <U7) C*3) 

RAIIGNAN T LIMEHCMA , MIXE D TYPE 

*BiCIAS7IKA L L.NCE E «U7) C>3) 

AIVECLAR/BBCNCHIOLAH CA, METASTA 

f eiSINlEEIC L. NOE E (U7) (13) 

I4iIS£O3_iI«iacaaJ._«iXED TYPE . _2_jaiL__ _. 3 JZ21 

# NURBE E CI ANIMAL S SITH TISSUE EXAMINE E MICROSCOPICALL Y 

* BUHBE E CE ANIMAL S NECEOPSIED 

**EXCLUDES PARTIALLY AUTOLYZED ANIMALS 

HIGH DCSE 

06-OU20 

50 

50 

50 

(50) 

(50) 

14 (28X) 

3 (6«) 

(50) 

1 (2») 

1 <2X) 

4 (8%) 

(»6)

1 (2») 

1 (2») 

(45) 

1 (2%) 

(45) 

1 (2X) 

(15) 

2_14*.L 

B-7 
TABLE B2 (CONTINUED) 

~ "~ 

COHTHOI (ONTR) IOW DCSE 

06-0360 06-0yi5 

#IIVI E (5«) (50) 

KAIIGNAN T LYMEHCMA , NO S 1 (255) 

4KIDNE Y (55) (50) 

rJIIGNAK T LYMEHCMA , MIXE C TYPE 1 <2X) 

#THYKU S (35) (1*1) 

THYKCK A 1 (3*) 

CIBCUIATCEY SYSTEM 

#HEART (£5) (50) 

AIVECLAB/BBCNCHIOLA B CA , METAST A 

HEMANGIOM A 1 (25!) 

DIGESTIVE SYSTE M 

iLIVER (5<*) (50) 

HEEATCCELLULA B ADENOM A « (7%) 11 (22X) 

HEPATOCELLOLA R CARCINOM A 7 (13«) 12 (24X) 

HEMANG10M A 1 (2% ) 2 (4%) 

tESCHHAGD S (51) <t7) 

SCUAKCU S CELL CABCINOMA 

#STC^AC H (53) (48) SCOAHCOS CELL EAPILLOMA 2 (<**) 10 (21») 

SQOABOt S CELL CARCINOM A 4 (8%) 

LEIOMYOSARCOM A 

URIhAR Y SYSTEf " 

*KICM Y (55) (50) 

laBULAF-CELL ADENOM A 2 (4») 

#UBIKAB Y BLADDEB (50) (43) 

HIHAKGICM A 

ENDCCEI M SYSTE M 

IEITUI1ABY CU2) (38) 

gHECBC|H?BI_ADENOM4_ . _ _ ^ . 2_J5«i__ _. 1 J3SJ 

I NUMBE F CF ANIMAL S HITH TISSU E EXAMINE D MICROSCOPICAIIY 

* &OMBE E CI ANIMAL S NZCBOPSIE D 

HIGH DOSE 

06-0420 

(49) 

(46) 

(36) 

(50) 

1 (2%) 

(49) 

15 (3158) 

20 (41X) 

1 (2%) 

(45) 

1 (2X) 

(<I4) 

18 (41») 

4 (9X) 

1 (2%) 

(46) 

2 (4X) 

(43) 

1 (2X) 

(39) 

B-8 
TABLE B2 (CONTINUED) 

HIGH DCSE 

06-0420 

2 (5X) 

(47) 

(47) 

2 (4X) 

(40) 

(44) 

1 (2X) 

(50) 

(46) 

1 (2X) 

2 (4X) 

(44)

1 (2X) 

1 (2X) 

1 (2X) 

2 (5X) 

(50) 

2_J4X.l 

EASOPBIL ADENOH A 

• ADEENA L 

IHECCHECMCCYTCM A 

tADEENAL/CAFSDLE 

AIEKKA , NO S 

tTHYFCI E 

KIIICULAB-CELL ADENOM A 

•PANCREATIC ISLETS 

IEIIT-CELL AEENCM A 

HEFRCIOCTIV E SYSTER 

*KAKEAE Y GLASC 

ACINAB-CELL CAECINOMA 

FIBROADENOMA 

fUTEEU S 

NECELASB , NCS, MALIGNAN T 

fEEBCCARCIKCMA , NO S 

IEICKYCSABCCM A 

E8DOMEIRIAL STROMAL POLYP 

HEMANGIOW A 

tCVAE Y 

CYS1ACENCKA , NO S 

PAPILLAR Y CYSTADENOMA, NOS 

GRANULOSA-CELL TUMOR 

GRANILOSA-CELL CARCINOMA 

HEMANGIOM A 

KERVCU S SYSTE M 

NOSE 

SPECIA L SE^S E CHGAN S 

*HAEEERIA N GLAN E 

CYSTAEEKCKA , NO S 

PAPILLAR Y £YSTADENOMAA NOS 

* KURBE B C f ANIMAL S WITH TISSU E

* KUBBE F O F ANIMAL S NECEOPSIE D 

CONTROL (UNTR ) 

06-0360 

1 (2%) 

(50) 

1 (2X ) 

(50) 

(48) 

1 (2X) 

(4S) 

(55) 

1 (2X) 

1 (2%) 

(54) 

1 (2X ) 

(50) 

(55) 

IOW DCSE 

06-0415 

(48) 

1 <2X ) 

(48) 

(44) 

(47) 

(50) 

(49) 

1 (2X) 

6 (12X) 

3 (6X) 

(47) 

1 (2X) 

(50) 

3 (6%) 

1 12&L 

 EXAMINE E MICROSCOPICALL Y 

B-9 
TABLE B2 (CONTINUED) 

HUSCOICSKEIE-IAL SYSTEM 

*SKGLL 

CS1ECHA 

EOD Y CAVITIE S 

*EESITCSEOM 

8ESCTHELICHA , NOS 

AIL CTHEB SYSTEMS 

*HOLIIPLE ORGAN S 

KESCTHELICHA , NOS 

HEMANGIOM A 

ANIBA I EI£ECSI1IC N SDHHAS Y 

ANIKAI S INITIALLY IN STODY 

KATUEA I EIATH8 

HOBIEUN D SACRIFICE 

JCH!ECIEE SACRIFICE 

ACCIEEKTALL Y KILLED 

TERKINA L SACBIFICE 

ANKA L KISSIN G 

3_Ili£L UBI s_JI22i U£&_&$ZULSf

 KOBBE R CF ANIMAt S WIT H TISSUE

* KOBBER Cf ANIMALS NICFOPSIBD 

CONTROL (ONTR) IOW DCSE HIGH DCSE 

06-0360 06-0115 C6-OM2 0 

(55) (50) (50) 

1 (2») 

(55) (50) (50) 

1 (2%) 

(55) (50) (50) 

1 (2%) 

1 (2%) 

55 50 50 

7 5 6 

a 7 5 

1 1 

M 37 38 

 EXAMINE D MICROSCOPICALL Y 

B-10 
TABLE B2 (CONCLUDED)
 

c:CNTROI (UNTE ; | LCW DCSE HIGH DOSE 

06-0360 06-OU15 06-0120 

TUMO E SCMMAR Y 

TOTA L ANIHAL S HIT H PRIMAR Y TUMORS * 3U 42 I4H

 

TCTAI EBIMAB Y TUMOE S 50 86 109

 

TCTA I AKIMAL S HITH BENIG N TUMORS 15 33 3U

 

TCTA L BEKIG N TUMOB S 19 US 67

 

TOTAI AMMAL S HITH MALIGNAN T TUMOR S 27 26 30

 

10TAL MALIGNAN T TUMORS 30 36 41

 

TOTA L ANIMAL S HIT H SECONDAR Y TOMCHS # 2 1 1

 

TCTAI SECCNCAE Y TUMOB S 2 1 2 

TCTA I AMMAL S HITH TUMOBS UNCERTAIN ­

EEMG N C F MAIIGNAN T 1 1 1

 

TCTA I UNCERTAI N TUMOBS 1 1 1

 

TOTA L ANIMAL S WIT H TUMORS UNCE8TAINPEIMAB Y OR METASTATIC

 

TCTAI UNCEETAI N TDMOBS 

* EEIKARY TUMCBS: ALL TUMOBS EXCEPT SECONDARY TUMORS
 

• SECCNEARY TUMORS: METASTATIC TUMORS OR TUMORS INVASIVE INTO AN ADJACENT OBGAN
 

B-ll
 

APPENDIX C
 

SUMMARY OF THE INCIDENCE OF NONNEOPLASTIC
 

LESIONS IN RATS TREATED WITH TBP
 

TABLE Cl

 

SUMMARY OF THE INCIDENCE OF NONNEOPLASTIC LESIONS IN MALE RATS TREATED WITH TBP 

HIGH DOSE 

01-0410 

55 

55 

55 

(55) 

3 (5%) 

1 (2%) 

(55) 

(55) 

(55) 

1 (2%) 

3 (5%) 

2 (4%) 

(52) 

1 (2% ) 

5 (10%) 

(52) 

1 (2») 

(51) 

CONTROL (UNTR )

01-0360

ANIMAL S INITIALL Y IN STUDY 55 

ANIHAI S I.ECECESIE E 5 4 

ANI1!AIS EXAMINE D HI STOEATHOLOGIC ALLY ** 54 

INTEGOHEKTAB Y SYSTE M 

*SKIN ,« 

EEICEBMA L INCLUSIO N CYS T 

ILCER, NOS 

AESCESS , NOS 

tLCER, HEALED 

*SUBCUT TISSUE (54) 

EEIEEBKA I INC 10 SIG N CYST 

BESEIEATCF Y SYSTE M 

#LUNG/ERCNCHU S 

BECKCHIECTASI S 

*LUK G 

BECNCHCESEUMCNIA ,

PNEUMONIA , CHRONIC

METAPLASIA , NOS 

HEMATCPCIETI C SYSTE M 

#BON E MARRO H 

EIBECSIS, FOCAL 

HYPOPLASIA , NOS 

HJPERPLASIA , NOS 

iSEIEEK 

BIBECEIS , EOCAL 

(>ECHCS1S , EOCAL 

HEHCSIDEECSI S 

HEMATOPOIESI S 

HCE6VICA L LYME H NOD E 

HY.fJEELASIA.,4 NOS_

(54 ) 

1 <2X ) 

 NO S 

 MURIN E 

(54) 

2 (4% ) 

2 (4%) 

(52) 

1 (2%) 

1 (13%) 

(54)

1 (2% ) 

1 (2%) 

1 (2X ) 

_ _ 

(53) _ _ «. 

 IOW DCSE 

 01-0405 

55 

55 

55 

(55) 

1 (2%) 

1 (2%) 

(55) 

1 (2% ) 

(55) 

1 (2%) 

(55) 

2 (4») 

1 (2%) 

(54) 

1 (2%) 

6 (11%) 

(54) 

(51) 

1 J2S1 

# NUKBE E CE ANIMAL S WITH TISSDE EXAMINE E MICROSCOPICALLY 

* KUP.BE E OE ANIMAL S NEC60PSIED 

**EXCLUDES PARTIALLY AUTOLYZED ANIMALS 

C-3 
TABLE Cl (CONTINUED) 

CONTROL (ONTR) IOW DOSE HIGH DCSE 

01-0360 01-0405 01-0410 

fLUBBA E LYBE H NOE E (53) (51) (51) 

HEMCEBHAG E 1 <2X) 

tfiESA L iYBEH NOD E 

HEMCSIEEBCSI S 

(53) (51) 

1 (2X) 

(51) 

CIRCOIATCR Y SYSTEM 

tHEART (54) (55) (55) 

THBCBBDS , MOBA L 

PERIAR1ERITIS 

1 (2X) 

1 (2X) 

1 12%} 

tMYCCABCIO M (54) (55) (55) 

INFIAKKATICN , FOCAL 1 (2X) 

EEGENERATICN , NO S 16 (30%) 22 (40X) 12 (22X) 

*ACBT A (54) (55) (55) 

THBOBBCSIS, NOS 1 <2X) 

MEDIA L CALCIFICATION 1 (2X) 

*CEIIAC ABTEB Y (54) (55) (55) 

THHCBBCSIS, NOS 1 (2X) 

*MESEN1ERIC ARTER Y (54) (55) (55) 

1HBCBBOS, MOBA L 1 (2X) 

CIGESTIVE SYSTE M 

*LI VER (54) (55) (54) 

CCNGESTICN , CHBCNIC PASSIV E 1 (2X) 

HENORREAG E 

CHOLANGIOFIBROSIS 9 (17*) 

1 (2X) 

5 (9X) 

NECROSIS, FOCAL 1 (2%) 2 (4%) 

NECROSIS , FAT 

METAMORPHOSI S FATTY 

1 (2X ) 

2 (U%) 1 (2%) 

EASOPHILIC CYTO CHANG E 1 (2%) 

FOCAL CELLULAR CHANG E 1 (2X) 

CLEAR-CELL CHANG E 1 (2X ) 

tLIVEB/CESlBILOEOLAR (54) (55) (54) 

»ECECSIS , NOS 1 (2X) 

*BIIE EUC1 (54) (55) (55) 

t NUREE B CF ANIMAL S HUH 1ISSOE EXABINE C MICBCSCOEICA LLY 

* SUBBE E 01 ANIMAL S NECBOPSIE D 

C-4 
TABLECl (CONTINUED) 

CONTROL (UNTR) IOW DOSE HIGH DOSE 

01-0360 01-0405 01-0410 

H1PEBPLASIA , NOS 

#EASCBEA S 

EILATAIICN/EOCI S 

PERIA8TEEITIS 

A1HOPKY , NOS 

ATROPHY, FOCAL 

tSTCKAC H 

OLCIB, NCS 

EEOSION 

CALCIFICATION , NOS 

HYPERPLASIA , BASAL CELL 

tCCIC N 

HYEEEIECEHY , NOS 

URINAB Y SYSTE M 

#KIENE Y 

HYEEClilEHROSI S 

PYELONEPHRITIS , NOS 

GLOMERCLONEPHRITIS , CHRONIC 

PYELONEPHRITIS, CHRONIC 

NEPHROSIS , NOS 

NEPHHOSIS, CHOLEHIC 

IKIENEY/1UBGLE 

MCBCSIS, NOS 

EYSELASIA , NOS 

#OfItiAB Y ELAEEE B 

INHIAfFATICN , ACUTE HEMORRHAGI C 

ENECCEI M SYSTE M 

tPITUITAR Y 

HEKCERHAG E 

HYPEEPLASIA , FOCAL 

HYPEHPLASIA, BASOPHILIC 

#ADEENA L 

CYS1 , NCS 

HEBCBEfcAG E _ 

f NUKEE E CF ANIHAL S HU H 1ISSUE

* KOHBI B Cf ANIMAL S NECEOPSIED 

1 12%) 

(53) (53) (51) 

1 (2X) 

1 (2%) 

1 (2%) 

2 (4%) 

(53) 

2 (4%) 

(54) 

1 (2%) 

(52) 

2 (4%) 

1 (2% ) 

2 (4%) 

14 (26X) 12 (22%) 14 (27%) 

(52) (50) (47) 

1 (2%) 

(53) (54) (54) 

1 (2%) 

1 (2%) 

1 (2%) 

2 (4%) 

26 

2 

(4SX) 

(4%) 

8 (15%) 

1 (2%) 

24 (44%) 

1 (2%) 

(53) (54) (54) 

1 (2%) 

6 (11%) 

(51) (51) 

1 (2%) 

(49) 

(46) (50) (50) 

1 (2%) 

1 

2 (2X )

(4X) 

(54) (55) (55) 

1 (2%) 

_J_J2Sl_ 

 EXAHIN1 E MIC RCSCOEICA LLY 

C-5 
TABLE Cl (CONTINUED)
 

CONTROL (UNTR ) I CW DOSE HIGH DCSE 

01-0360 01-0405 01-0410 

HENOBRbAGI C CYST 1 (2X ) 

#AEEINA L CCBTE X (54) (55) (55)

 

HYEEBELASIA , NO S 1 (2% )

 

fADRENA L MEDULL A (54 ) (55) (55) 

HYEEEELASIA , NO S 3 (5X) 

fTHYECi r (53) (51) (52) 

HYEEFELASIA , C-CELL 1 (2%) 

#PAFA1HYECI E (26) (23 ) (19)

 

HYEEEEIASIA , NO S 6 (26%)

 

#EAkCEEATI C ISLI1S (53) (53) (51)

 

HYEEBELASIA , NO S 1 (2% ) 1 (2%)

 

REPECIUCTIV E SYSTE M 

*MAMMAR Y GLAN D (54) (55) (55)

 

G JIACTCCEL E 1 (2X)

 

INFLAMMATION , G8A NU LOMATOU S 1 (2%)

 

LACTATIO N 1 (2%)

 

*PEEEUTIA L GLAN E (54) (55 ) (55)

 

ABSCESS , NCS 1 (2%)

 

INFIAfKATICN , CHECNI C 1 (2*)

 

#EECS1AT E (52) (55) (53)

 

INEIAPKATIC N ACUT E AN D CHRONIC 1 (2%)

 

#TES1IS (54 ) (55) (55) 

ATECEHY , NC S 1 (2%) 

HYPERPLASIA , INTERSTITIAL CEL L 2 (4%) 2 (4% ) 

NERVCU S SYSTE M 

tCEEEEEA L VEKTEICL E (54) (55) (55)

 

HIKCFEHAG E 1 (2% )

 

IBBAI N (54) (55) (55)

 

HYEBCCEEHALUS , NO S 1 (2% ) 

HEMORRl-AG E 1 (25E ) 1 (2%)

 

SCEEEBELLU M (54) (55) (55)

 

HiJ3£££Hiai _ . 1 12*}

 

# NUCBI E CF ANIMALS WITH 1ISSOE EXAMINEE MICROSCOPICALLY
 

* KURBE B CE ANIMALS NECEOPSIED
 

C-6
 
TABLE Cl (CONCLUDED) 

CONTROL (UNTB) IOH DCSE HIGH DCSE 

01-0360 01-0405 01-0410 

SPECIAL SE^SE CBGANS 

*EYE (54) (55) (55) 

HEHCBBHAG E 1 (2%) 1 (2X) 

CATABACT 1 (2%) 

*EYI/LACEIflAL GLAN E (54) (55) (55) 

INEIARKATICN , NOS 1 (2») 

BOSCOICSKEIETA L SYSTE M 

MCK E 

BODY CAVITIE S 

*AEDOHINAL CAVITY (54) (55) (55) 

PETECHI A 1 (2%) 

HECBOSIS, FAT S (!"?*) 4 (7X) 5 (9S5) 

A IL CTHE E SYSTEMS 

THORA X 

EEEIA8TEBITI S 1 

OHEKTC R 

INFLAMMATION , GB ANULO M ATOUS 1 

SPECIAI C.CBPHCLOGY SUMMAR Y 

AUTCIYSIS/N C NECECES Y 1 

t NOMEE F OF ANIMAL S MTH TISSUE EXAKINE E HICRCSCOEICAIIY 

* KUBBE E CF ANIMAL S NECBOPSIE E 

C-7 
TABLE C2 

SUMMARY OF THE INCIDENCE OF NONNEOPLASTIC LESIONS IN FEMALE RATS TREATED WITH TBP 

1CONTROL (UNTE) LOW DCSE HIGH DCSE 

02-0360 02-0405 02-0410 

ANIMAL S INITIALL Y I N STOD Y 55 55 55 

ANIBAI S fcECBCESII D 54 55 55 

ANIBAI S EXAMINE D HISTOFATHOLOGIC ALLY** 54 55 55 

INTEGUBEMAB Y SYSTE M 

NCK E 

RESEIBATCE Y SYSTEM 

ILUNG/EBONCHU S (53) (54) (55) 

BECtiCHIECTASI S 1 (2%)

 

HON G (53) (54) (55) 

EKEUMCNIA , CHRONIC MUBIN E 3 (6%) 1 (2%) 1 (2X) 

METAPLASIA , NOS 1 (7%) 2 (4%) 

HENATCPCIETI C SYSTE M 

#BONE MARRO W (53) (54) (52) 

HISTICCYTCSI S 1 (2%) 

HiPERPLASIA , HEMATOPOIETIC 3 (6X) 1 (2%) 

HiPOPLASIA , HEMATOPOIETIC 1 (235) 

#SEIEE K (52) (54) (55) 

IKFABC1 , NCS 1 (2X) 

HEMATOPOIESI S 1 (2X ) 1 (2%) 

#LUf!BA B LYME H NOD E (51) (54) (54)

 

INPIACHAIICN , CHBONIC 1 (2%)

 

HYPEEPIASIA , NC S 1 (2»)

 

#6ENA L LYMP H NODE (51) (54) (54)

 

INFIAFCAIICN , CHEONIC 1 (2%)

 

CISCUIATCE Y SYSTE M 

IHEAR T (53) (54) (55) — IlilABTEBIIIS _ _ . JL122I 

# NUKBE B CE ANIMAL S WIT H TISSUE EXAMINE D MICROSCOPICALI Y 

* KOHBE B O E ANIMAL S NECEOPSIE D 

**EXCLUDES PARTIALLY AUTOLYZED ANIMALS 

C-8 
TABLE C2 (CONTINUED) 

CONTROL (ONTR) LOW DCSE HIGH DOSE 

02-0360 02-0105 02-0410 

IMYCCABIIU M <53) (5«) (55)

 

INELAHtATICN , CHBONIC 1 (2X)

 

DEGENERATION , NOS 6 (11*) 1 (13X) 3 (5X)

 

DIGESTIV E SYSTEM 

#LIVE R (53) (5i») (55) 

CHCLAMGIOFIBEOSIS 2 <4«>

 

METAMORPHOSI S PATTY 6 (11«) H (7X) 2 (4X)

 

EASOPBILIC CYTO CHANGE 10 (19X) 1U (26X) 12 (22X)

 

CLEAR-CELL CHANG E 1 (2X)

 

*PA»CREA S (52) (53) (5U)

 

INBIAKBATICN , FOCAL 7 (13X)

 

INFLAMMATION , CHRONIC 1 (2X) 

AJROP-HY, FOCAL 1 (2X)

 

ISICfACH (51) (5«) (52)

 

ULCEB, NCS 1 (2X) 1 (2X) 1 (2X) 

HYPBBPLASIA, BASAL CELL 11 (22X) 9 (17X) 22 (42X) 

URINAR Y SYSTEM 

IKIDNE Y (52) (54) (5U)

 

EYELCNEEHBITIS , CHEONIC 1 (2X)

 

NEPHROSIS, NOS 2 («») 2 (4X) 

NEPEROSIS , CHOLEMIC 1 (2*) 1 (2X)

 

GLOMERDLOSCLEROSIS, NOS 1 (2*)

 

CALCIFICATION , FOCAL 5 (1CX) 

tKID»EY/lUBOL E (52) (5<*) (54)

 

ECCAI CELLULA R CHANGE 3 (6X) 

DYEPLASIA , NOS 35 (65X)

 

ENCCCHI M SYSTEM 

IEITOITAB Y 4<*6) (5U) (52)

 

HEMCEBHAGIC CYST 1 (2X)

 

H1PERPLASIA, NOS 1 (2X) 1 (2X) 

• AD6EKA L (53) (53) (54) 

_ _UCii5IJ*.flfl5 1 JiSl,_TM ^iJM.MML^m,——^— __ .««.. 

t NURBE F CF ANIMAL S HUH TISSUE EXAMINE C MICROSCOPICALLY 

* SUMBE E CE ANIMALS NECfOPSIED 

C-9 
TABLE C2 (CONTINUED) 

CONTROL (ONT8) ICH DCSE 

02-0360 02-0405 

#AEEHNA l CCBIE X (53) (53)

 

HYEEBEIASIA , NO S 1 (2%)

 

#ACBINA I KEEULLA (53) (53) 

MCECSIS, NOS 1 (2%) 

HYPIBEIASIA , NO S 1 I2X ) 

tPARATHYROI D (15) (26)

 

HYEEFELASIA , NO S 1 (1%)

 

«EAKCBEATI C ISLET S (52) (53)

 

HYEEEEIASIA , NO S 1 (255)

 

REEECDUCTIV E SYS1EM 

*HAHI!AB Y GLAN D (50 ) (55) 

GALACTOCEL E 6 (11*) 6 (15X) 

AESCESS, NOS 1 (2%) 

LACTATIO N 

*UTIBO S (52) (5«)

HYIFCeiTB A 2 (US) 2 <4X) 

EPIDERMA L INCLUSION CYST 1 (2«) 

THROMBOSIS , NOS 1 (2X ) 1 (2X) 

PJOMETR A 1 (2%) 

AESCESS , NOS 

tCEBVI X OTEBI (52) (54)

 

EC1YE , INFLAHMATOF Y 1 (2% ) 

#OTEROS/ENDOHETRIO M (52) (54) 

CYST, NOS 

INFLAMMATION ACUTE AND CHRONIC 1 (2%) 

HYPERPLASIA , CYSTIC 

#CVABY/CVIDUC T (52) (54) 

ABSCESS, NOS 1 (2*) 3 (6«) 

#FAFAHETBIU H (52) (54)

 

CYST , NCS 

tCVAB Y (53) (53)

 

CYST , SOS 

_AJSCSSS^_fiOS 

* NUBBE R CF ANIMAL S WITH TISSUE EXAMINE D MICROSCOPICALL Y 

* KUBBE B CE ANIMAL S NECBOPSIED 

HIGH DCSE 

02-0410 

( = 4) 

1 (2X) 

(54) 

(26) 

(54) 

(55) 

2 (4X) 

1 (2X) 

(55) 

1 (2%) 

(55) 

(55) 

1 (2X) 

1 (2X) 

(55) 

2 (4X) 

(55) 

1 (2X) 

(55)

1 (2*) 

_1_J221 

C-10 
TABLE C2 (CONCLUDED) 

CONTROL (ONTR) IOW DCSE HIGH DCSE 

02-0360 02-0405 02-0110 

INFLAMMATION , C6RONI C 1 (2X) 

NBRVCU S SYSTE M 

*ERAIN/MENINGE S (52) (51) (54) 

INFIAKSATICN , ACUT E 1 (2») 

#BfAI N (52) (54) (£4) 

HYIFCCEEHALOS , NOS 3 (6%) 1 (256) 

HEMORRtAG E 1 (2%) 

SPECIA L SEdS E CBGAN S 

*EYI (54) (55) (55) 

EHTHISI S BULBI 1 (2%) 

MUSCUICSKIIETA L SYSTEM 

*SKDLL (54) (55) (55) 

CSTICSCLEECSI S 1 (2%) 

BOC Y CAVITIE S 

*ABDOMINA L CAVIT Y (54) (55) (55) 

IECECSIS, FAT 6 (11%) 2 (4X) 4 (7%) 

A L L CTHIB SYSTEM S 

ADIPOSE TISSUE 

INFLABRATICN , GEANOLO M ATOU S 1 

SPECIAL MOBPHOLOG Y SUMMAR Y 

NO LESIO N REPORTE D 2 

AUIC/bECBCESY/HIST O PERF 1 

AUTCLYSIS/N C NECEOES Y 1 

# NUMEE R O F ANIMAL S WITH TISSUE EXAMINE E MICEOSCOPICALLY 

* MP.BEE OF ANIMAL S NECBOPSIE D 

C-ll 

APPENDIX D
 

SUMMARY OF THE INCIDENCE OF NONNEOPLASTIC
 

LESIONS IN MICE TREATED WITH TBP
 

TABLE Dl

 

SUMMARY OF THE INCIDENCE OF NONNEOPLASTIC LESIONS IN MALE MICE TREATED WITH TBP 

<:CNTBOL (UNTR ) IOH DCSE 

05-0360 05-0415 

ANIMAL S INITIALL Y I N STUD Y 55 50 

AKIfAI S >ECECESIB C 55 50 

ANIMAI S EXAMINE E HI STOEA1HOLOGIC ALLY** 55 50 

INTEGUKEMAE Y SYSTE M 

*SKIN (55) (50) 

EEIEEEMA L INCLUSIO N CYS1 1 (2*) 

PERIVASCULITI S 1 (2%) 

CALCIFICATION , NOS 1 (2% ) 

POLYP , INFLAMMATOR Y 1 (2% ) 

*SUBCU T 1ISSGE (55) (50) 

HEfATCCA , NO S 

GHAMJICFA , NC S 

RESEIEATCB Y SYSTE M 

*LARYN X (55) (50) 

HYEEEELASIA . P SEUEOEPI1HELIOMAT C 

HEBJTCPCIETI C SYSTE M 

#BON E MARROf e (51) (44 ) 

HYEE f EIASIA , H EMATOEO I ETIC 

*SEl!Eli (51) (47 ) 

CCNGIS1ICN , NO S 1 (2% ) 

HEMJTOPOIESI S 2 (4X ) 1 (2%) 

fKESENTEBI C L . NCE E (48) (43) 

CC NGIS1IC t(, NOS 6 (13% ) 

FYPEBEIASIA , NC S 1 (2% ) 

USTICCYTCSI S 1 (2*) 

HSMATOPOIESI S 1 (2%) 

CIBCUIATCF Y SYST5 M 

_ NCN E __ _ 

# NUFBE B C E ANIMAL S WIT H TISSUE EXAMINE D MICROSCOPICALL Y 

* NUCBE E C E ANIMAL S NECEOPSIE D 

**EXCLUDES PARTIALLY AUTOLYZED ANIMALS 

HIGH DCSE 

05-0420 

50 

50 

50 

(50) 

1 (2X ) 

(50) 

1 (2X) 

1 <2X ) 

(50) 

1 (2%) 

(48) 

1 (2») 

(49) 

3 (6%) 

(44) 

D-3 
TABLE Dl (CONTINUED) 

CONTROL (UNTR ) IOH DCSE 

05-0360 05-OU15 

EIGES1IVI SYSTE M 

tSALIVAR Y GLAN D 

CALCULUS , NOS 

(53) (50) 

*IIVEB 

BASCEHILIC CY10 CHAN

HYPEHPLASIA , NOS 

G E 

(54) 

1 (2*) 

(«9) 

1 (2%) 

*GAIIBLAEEE B 

CIIATATICN , NOS 

(55) (50) 

*BILE DCCI 

CILA1A1ICN, NCS 

(55) (50) 

1 (2%) 

*EA!iCBEAS 

CYST, NOS 

ATROPHY , NOS 

<49 ) 

1 (2%) 

(46) 

1 (2X) 

#STCKAC H 

lEIIEBtA L INCLUSIO N CYS1 

INFLAHHATION , ACOTE 

ATYPIA , NO S 

HYPEBPLASIA , BASAI CELL 

(51) 

1 (2% ) 

1 (2% ) 

(47) 

1 (2») 

DBIKAB Y SYSTE K 

#KIEbE Y (54) (50) 

HYrBCKIEHECSI S 1 (2%) 

CYS1, NOS 

PYELONEPHRITIS , ACUT E 1 (2*) 

INFLAMMATION , CHRONIC 1 (2%) 

PYELONEPHRITIS , CHRONIC 1 (2% ) 

DYSPLASIA , NO S 37 (74X) 

#DfIKAB Y BLACEE B ««8) (38) 

CALCULUS , NO S 1 (2%) 1 13*) 

H1PERPLASIA , EPITHELIA L 1 (255) 3 (8%) 

DJSPLASIA , NO S 1 (35J) 

ENECCBI M SYSTE M 

#PANCRKATI C ISLETS (US ) (46) 

__MIIIIIASIit_NOS , .12 I24JJ . .. 3 J7£l 

f tiUKBE E CF ANIMAL S WITH TISSU E EXAMINE D MICKOSCOPICA HY 

* MMBE F C B ANIMAL S NECEOPSlE D 

HIGH DCSE 

05-0420 

(49) 

1 (2X) 

(49) 

(50) 

1 (2%) 

(50) 

(49) 

(48) 

1 (2%) 

(49) 

1 (2%) 

30 (61S) 

(47) 

2 (4?5) 

(49) 

_J_I21L 

D-4 
TABLE Dl (CONTINUED) 

CONTROL (ONTR; ) 1CW DCSE HIGH DOSE 

05-0360 05-0415 05-0420 

EEFBCIUCTIV E SYSTE M 

*PREPOTIAI GLAND (55) (50) (50) 

CALCULUS , NO S 1 (2%) 

DILATATION , NOS 1 (2%) 

EPIDERMA L INCLUSION CYST 1 (2%) 

AESCESS , NOS 1 (2%) 

#PECSTAT E (52) (42) (39) 

IKEIARKATICN , ACUTE 1 (2») 

*TES1IS 

ATECEHY , FOCAL 

(5<4) (49) (50)

2 (4S) 

HYPOSPEBHAT O GENES IS 1 (2%) 

*SCECTU B (55) (50) (50) 

BIHATCtA , NCS 1 (2%) 

hERVCU S SYSTE M 

f ERAI N 

EEFIVASCULITI S 

(52) (46)

1 (2%) 

 (50) 

SPECIAL SEKS E CRGAN S 

*EYE (55) (50) (50) 

INFIAMJATICN ,

CATARACT 

 ACUT E 1 (2%) 

1 (2X) 

MUSCULCSKIIETA L SYSTEM 

NCK E 

EOE Y CAVITJE S 

+AECCKIKA I CAVIT Y 

&ECECSIS , BAT 

(55) 

5 (9X) 

(50) (50) 

*EEEITCNEU U (55) (50) (50) 

t NUMEE E O F ANIMAL S WIT H TISSUE EXAMINE D HICSCSCOEICALL Y 

* NUf!BE 6 OF ANIMAL S NECEOPSII D 

D-5 
TABLED1 (CONCLUDED) 

CONTROL (UNTR )

05-0360

 LOW DCSE 

 05-0415 

HIGH DOSE 

05-0420 

AIL C-IHIE SYSTEMS 

OHENTC M 

HEPA1CPA , NO S 1 

SPECIAL MORPHOLOG Y SUMMAR Y 

# NtKEER CE AKIMALS WITH 1ISSUE EXAMINEE MICEOSCOPICALLY 

* KUKBEE CE ANIMALS NEC80PSIED 

NO LESION 8EPORTE D 

AUTC/KECRCESY/HISIO PEBF 

e

1 

5 

D-6 
TABLE D2 

SUMMARY OF THE INCIDENCE OF NONNEOPLASTIC LESIONS IN FEMALE MICE TREATED WITH TBP 

(:ONTHOI. (UNTB) IOW DCSE HIGH DCSE 

06-0360 06-0415 06-0420 

ANIHAL S INITIALL Y I N STUD Y 55 50 50 

AHIBAI S ^ECBC£SIE C 55 50 50 

AHItAl S EXAMINE E HI STOEATHOLOGICALLY ** 55 50 50 

INTEGDHEKTAB Y SYSTE M 

N C M 

BESEIBATCB Y SYSTE M 

*LUN G (55) (50) (50) 

ATELECTASI S 1 <2X ) 

HEMORfitAG E 2 (4%) 

EBONCHOPNEOMONIA , NOS 1 (2») 

HEBATCECIETI C SYSTEH 

*BONE HABRO H (52) (49) (46) 

HYEICFIBBCSI S 31 (60%) 31 (63S) 30 (65») 

HYPEBPLASIA , HEHATOPOIETIC 1 (2% ) 

#SEIEE N (53) (47) (46) 

HIFAICICIESI S 1 (2%) 4 (9%) 

#RESEN1EBI C L. NCC E (47) (43 ) (45) 

CChGESlICk , NO S 1 <2X ) 

BYPEEEIASIA , BO S 2 (4X ) 1 (2X> 

CIBCOIA1CE Y SYSTE H 

fHEAR T (55) (50) (50)

 

EIBIABIIEI-IIS 1 (2% ) 

DIGESTIV E SYSTE M 

*LIVER (54 ) (5C) C*9). 

_ -llISiCSIi^.lOCAi __ J_J2Xi 

* NUPBE B Cf ANIMAL S WITH 1ISSDE EXAMINE E MICROSCOPICALL Y 

* hUHBE B O B ANIMAL S NECBOPSIZD 

**EXCLUDES PARTIALLY AUTOLYZED ANIMALS 

D-7 
TABLE D2 (CONTINUED) 

METAMORPHOSI S FATTY 

#EANCEEA S 

IIIAIAIICN/DUCI S 

CYS1. NOS 

INFLAHHATION, CbRONIC 

A1ROP6Y , NOS 

tESCEHAGU S 

HYEIBEIASIA , BASA L CELL 

*STCKAC H 

ULCER , NC S 

ERCSK N 

HJPERPLASIA , EPITHELIAL 

HYPEBPLASIA , BASAL CELL 

#OBJUKU K 

EIVEBIICULU M 

AMYLOIDOSI S 

UHINAB Y SYSTE P 

fKIDNE Y 

iYELCNHEHEIlIS , CHEONI C 

NEPFROPATH Y 

INFARC1 , FOCAL 

DYSPLASIA , NO S 

#U£INAF Y BLACCE R 

INFLACPATICN , CHEONIC 

DYSPLASIA , NOS 

ENCCCEI M SYSTE M 

#PANCREATI C ISLETS 

HYPEEELASIA , NO S 

REPRCIUCTIV E SYSTE M 

IU1ERL S 

HYEECfEaE A 

PYOMETR A 

# NUPBE B CE ANIMAL S WI1H TISSUE

* KUCBE E Cf ANIMAL S NECEOPSIE D 

CONTROL (UNTH ) IOW DCSE 

06-0360 06-01415 

1 (2%) 

(H9) (47) 

1 (28) 1 (2X) 

2 (DX) 

1 (2% ) 1 (9%) 

(51) (47) 

(53) (48) 

1 (2X) 

1 (2X ) 

2 (HX ) 

(52) (48) 

1 (2%) 

1 (2%) 

(55) (50) 

1 (2%) 

1 (2%) 

(50) (43) 

1 <2X ) 

1 (2%) 

(US) (47) 

3 (6X ) 1 (2%) 

(54) (49 ) 

3 (6X) 

 EXAMINE D MICROSCOPICALL Y 

HIGH DCSE 

06-0420 

3 (6X) 

(4<t) 

1 (2X) 

2 (5X) 

(45) 

2 (4X) 

(44) 

3 (7X) 

(46) 

(46) 

1 (2X) 

1 <2X ) 

12 (26X) 

(43) 

9 (21X) 

(44) 

(46) 

1.J2IJ 

D-8 
TABLE D2 (CONTINUED) 

CONTROL (UNTR) ICW DCSE 

06-0360 06-OU15 

#01BBOJ/IKECMHTEID B (54) (49) 

HYPEEFLASIA , CYSTIC 15 (28%) 16 (33%) 

#CVAB Y (50) (47) 

CYST , NO S 7 (1435) 1 (2%) 

1HROMEOSIS, NOS 

HEMORRBAGI C CYST 1 (2%) 

AEECESS , NOS 1 (2*) 

AMYLOIDOSI S 1 (2%) 

NEBVCU S SYSTE M 

#E6AIh/K£MNGE S (55) (48)

 

INBIAM!ATICN, NOS 1 (2«) 

#BFAI N (55) (48)

 

HYEECCEFHALOS , NO S 2 (H%)

 

SPECIA L SEIS E CEGAN S 

fHARDEBIAi : GLAND (55) <5C) 

INFLAMMATION , CfcBONIC 

HUSCUICSKEIETA L SYSTEM 

NCK E 

EOC Y CAVITIE S 

*AEECKIt. n CAVIT Y (55) (50) 

MCECSIS, FAT 7 (13%) 2 (6X) 

*EEEI1CKEU M (55) (50) 

INFLAffATICN , NO S 1 (2X) 

INFIAfKATICN , ACD1E 1 <2X ) 

*KESEKTEE Y (55) (50) 

CYST , NCS 1 (2X )

 

A L L CTHE B SYSTEM S 

*MOLTIPL E ORGAN S (55) (50)

 

FJilAJimils 1 J2J1 _

 

# NUKBEE CF ANIMALS WITH TISSUE EXAMINEE MICROSCOPICALLY
 

* KURBE E CF ANIMALS NECBOPSIED
 

HIGH DCSE 

06-0420 

(46) 

23 (50%) 

(44) 

1 (2%) 

2 (5X) 

(48) 

(48) 

(50) 

1 (2% ) 

(50) 

2 (4J5) 

(50) 

(50) 

(50) 

J_12«l__ _ 

D-9
 
TABLE D2 (CONCLUDED) 

CONTROL (UNTR) IOW DOSE HIGH DCSE 

06-0360 06-0415 06-0420 

SPECIAI KCEEHCLOG Y SOMHAB Y 

KC IESIC N EEEOE1E D 1 4 1 

AUTC/SECBCESY/HISIO EEBF 1 

« NOMEE R OF JNIMALS 8 IT H TISSUE EXAKIM I RIC ECSCO EICAIIY 

* MOKBE E OF ANIMAL S NECBOPSIB D 

4 U. S. GOVERNMENT PRINTING OFFICE : 1978 260-899/3049 

D-10 
Review of the Bioassay of
 

Tris(2,3-dibromopropyl)phosphate* (TRIS) for Carcinogenicity
 

by the Data Evaluation/Risk Assessment Subgroup of the
 

Clearinghouse on Environmental Carcinogens
 

March 6, 1978
 

The Clearinghouse on Environmental Carcinogens was
 

established in May, 1976, in compliance with DHEW Committee
 

Regulations and the Provisions of the Federal Advisory
 

Committee Act. The purpose of the Clearinghouse is to
 

advise the Director of the National Cancer Institute (NCI)
 

on its bioassay program to identify and to evaluate chemical
 

carcinogens in the environment to which humans may be
 

exposed. The members of the Clearinghouse have been drawn
 

from academia, industry, organized labor, public interest
 

groups, State health officials, and quasi-public health
 

and research organizations. Members have been selected
 

on the basis of their experience in carcinogenesis or
 

related fields and, collectively, provide expertise in
 

laboratory animal sciences, chemistry, biochemistry, bio­ statistics, toxicology, pathology, and epidemiology.
 Representatives of various Governmental agencies participate
 

as ad hoc members. The Data Evaluation/Risk Assessment
 

Subgroup of the Clearinghouse is charged with the respon­ sibility of providing a peer review of reports prepared on
 

NCI-sponsored bioassays of chemicals studied for carcinogenicity. It is in this context that the below critique
 

is given on the bioassay of Tris(2,3-dibromopropyl)phosphate
 

(TRIS) for carcinogenicity.
 

The primary reviewer noted that TRIS has been shown
 

to be mutagenic. He agreed with the conclusion in the
 

report that TRIS was carcinogenic in both rats and mice.
 After a brief description of the experimental design,
 he noted that the tumors were detected after a relatively
 

long latent period. Based on the multiple target organ
 

effect, the primary reviewer suggested TRIS may be a
 

direct acting carcinogen.
 

The secondary reviewer agreed with the earlier critique
 

of the study. He pointed out, however, the lower incidence
 

of leukemia among the treated male rats as compared to
 

their associated controls. He said that such a negative
 

trend also should be noted as an effect.
 
It was moved that the report on TRIS be accepted as
 

written. The motion was seconded and approved unanimously.
 

Members present were
 

Gerald N. Wogan (Chairman), Massachusetts Institute of
 

Technology
 

Arnold Brown, Mayo Clinic
 

Lawrence Garfinkel, American Cancer Society
 

E. Cuyler Hammond, American Cancer Society
 

Joseph Highland, Environmental Defense Fund
 

Henry Pitot, University of Wisconsin Medical Center
 

George Roush, Jr., Monsanto Company
 

Sheldon Samuels, Industrial Union Department, APL-CIO
 

Michael Shimkin, University of California at San Diego
 

John Weisburger, American Health Foundation
 

Sidney Wolfe, Health Research Group
 

*	 Subsequent to this review, changes may have been made
 

in the bioassay report either as a result of the review
 

or other reasons. Thus, certain comments and criticisms
 

reflected in the review may no longer be appropriate.
 

DHEW Publication No. (NIH) 78-1326