ACUTE EXPOSURE GUIDELINE LEVELS (AEGLs) 

FOR 

TELLURIUM HEXAFLUORIDE 

CAS Reg. No. 7783-80-4 

PROPOSED 
TELLURIUM HEXAFLUORIDE Proposed: April 2009 

2

1 

2 

3 

4 

5 

6 

7 

8 

9 

10 

11 

12 

13 

14 

15 

16 

17 

18 

19 

20 

21 

22 

23 

24 

25 

26 

27 

28 

29 

30 

31 

32 

33 

34 

35 

36 

37 

38 

39 

40 

41 

42 

43 

ACUTE EXPOSURE GUIDELINE LEVELS (AEGLs) 

FOR 

TELLURIUM HEXAFLUORIDE 

(CAS Reg. No. 7783-80-4) 

PROPOSED 

 

Oak Ridge National Laboratory, managed by UT-Battelle, LLC, for the U.S. Dept. of Energy under 

contract DE-AC05-00OR22725 
TELLURIUM HEXAFLUORIDE Proposed: April 2009 

3

1 

2 

3 

4 

5 

6 

7 

8 

9 

10 

11 

12 

13 

14 

15 

16 

17 

18 

19 

20 

21 

22 

23 

24 

25 

26 

27 

28 

29 

30 

31 

32 

33 

34 

35 

36 

37 

38 

39 

40 

PREFACE 

Under the authority of the Federal Advisory Committee Act (FACA) P. L. 92-463 of 

1972, the National Advisory Committee for Acute Exposure Guideline Levels for Hazardous 

Substances (NAC/AEGL Committee) has been established to identify, review and interpret 

relevant toxicologic and other scientific data and develop AEGLs for high priority, acutely toxic 

chemicals. 

AEGLs represent threshold exposure limits for the general public and are applicable to 

emergency exposure periods ranging from 10 minutes to 8 hours. Three levels C AEGL-1, 

AEGL-2 and AEGL-3 C are developed for each of five exposure periods (10 and 30 minutes, 1 

hour, 4 hours, and 8 hours) and are distinguished by varying degrees of severity of toxic effects. 

The three AEGLs are defined as follows: 

AEGL-1 is the airborne concentration (expressed as parts per million or milligrams per 

cubic meter [ppm or mg/m3]) of a substance above which it is predicted that the general 

population, including susceptible individuals, could experience notable discomfort, irritation, or 

certain asymptomatic, non-sensory effects. However, the effects are not disabling and are 

transient and reversible upon cessation of exposure. 

AEGL-2 is the airborne concentration (expressed as ppm or mg/m3) of a substance above 

which it is predicted that the general population, including susceptible individuals, could 

experience irreversible or other serious, long-lasting adverse health effects or an impaired ability 

to escape. 

AEGL-3 is the airborne concentration (expressed as ppm or mg/m3) of a substance above 

which it is predicted that the general population, including susceptible individuals, could 

experience life-threatening health effects or death. 

Airborne concentrations below the AEGL-1 represent exposure levels that could produce 

mild and progressively increasing but transient and nondisabling odor, taste, and sensory 

irritation or certain asymptomatic, non-sensory effects. With increasing airborne concentrations 

above each AEGL, there is a progressive increase in the likelihood of occurrence and the severity 

of effects described for each corresponding AEGL. Although the AEGL values represent 

threshold levels for the general public, including susceptible subpopulations, such as infants, 

children, the elderly, persons with asthma, and those with other illnesses, it is recognized that 

individuals, subject to unique or idiosyncratic responses, could experience the effects described 

at concentrations below the corresponding AEGL 
TELLURIUM HEXAFLUORIDE Proposed: April 2009 

4

1 

2 

3 

4 

5 

6 

7 

8 

9 

10 

11 

12 

13 

14 

15 

16 

17 

18 

19 

20 

21 

22 

23 

24 

25 

26 

27 

28 

29 

30 

31 

32 

33 

34 

35 

36 

37 

38 

39 

40 

41 

42 

43 

44 

45 

46 

47 

48 

49 

50 

TABLE OF CONTENTS 

PREFACE.....................................................................................................................................................3

EXECUTIVE SUMMARY ..........................................................................................................................6

1. INTRODUCTION................................................................................................................................7

2. HUMAN TOXICITY DATA...............................................................................................................7

2.1. Acute Lethality ................................................................................................................................7

2.2. Nonlethal Toxicity ...........................................................................................................................7

2.2.1. Odor Threshold/Odor Awareness............................................................................................7

2.2.2. Case Reports............................................................................................................................7

2.3. Neurotoxicity ...................................................................................................................................8

2.4. Developmental/Reproductive Toxicity............................................................................................8

2.5. Genotoxicity.....................................................................................................................................8

2.6. Carcinogenicity................................................................................................................................8

2.7. Summary..........................................................................................................................................8

3. ANIMAL TOXICITY DATA..............................................................................................................8

3.1. Acute Lethality ................................................................................................................................8

3.2. Nonlethal Toxicity ...........................................................................................................................9

3.3. Developmental/Reproductive Toxicity............................................................................................9

3.4. Genotoxicity...................................................................................................................................10

3.5. Chronic Toxicity/Carcinogenicity .................................................................................................10

3.5. Summary........................................................................................................................................10

4. SPECIAL CONSIDERATIONS........................................................................................................10

4.1. Metabolism and Disposition ..........................................................................................................10

4.2. Mechanism of Toxicity..................................................................................................................10

4.3. Structure Activity Relationships....................................................................................................10

4.4. Other Relevant Information ...........................................................................................................11

4.4.1. Species Variability ................................................................................................................11

4.4.2. Susceptible Populations ........................................................................................................11

4.4.3. Concentration-Exposure Duration Relationship ...................................................................12

4.4.4. Concurrent Exposure Issues..................................................................................................12

5. DATA ANALYSIS FOR AEGL-1 ....................................................................................................12

5.1. Summary of Human Data Relevant to AEGL-1 ............................................................................12

5.2. Summary of Animal Data Relevant to AEGL-1............................................................................12

5.3. Derivation of AEGL-1 ...................................................................................................................12

6. DATA ANALYSIS FOR AEGL-2 ....................................................................................................12

6.1. Summary of Human Data Relevant to AEGL-2 ............................................................................12

6.2. Summary of Animal Data Relevant to AEGL-2............................................................................12

6.3. Derivation of AEGL-2 ...................................................................................................................13

7. DATA ANALYSIS FOR AEGL-3 ....................................................................................................13

7.1. Summary of Human Data Relevant to AEGL-3 ............................................................................13

7.2. Summary of Animal Data Relevant to AEGL-3............................................................................13

7.3. Derivation of AEGL-3 ...................................................................................................................13

8. SUMMARY OF AEGLS ...................................................................................................................14

8.1. AEGL Values and Toxicity Endpoints..........................................................................................14

8.2. Comparison with Other Standards and Guidelines........................................................................14

8.3. Data Adequacy and Research ........................................................................................................15

9. REFERENCES...................................................................................................................................16

APPENDIX A: DERIVATION OF AEGL VALUES...............................................................................18

APPENDIX B: DERIVATION SUMMARY FOR TELLURIUM HEXAFLUORIDE AEGLS .............21

APPENDIX C: CATEGORY PLOT FOR TELLURIUM HEXAFLUORIDE.........................................24
TELLURIUM HEXAFLUORIDE Proposed: April 2009 

5

1 

2 

3 

4 

5 

6 

7 

8 

9 

10 

11 

LIST OF TABLES 

TABLE 1. Summary of AEGL Values for Tellurium Hexafluoride ...........................................................6 

TABLE 2. Chemical and Physical Properties.............................................................................................7 

TABLE 3. Summary of Acute Inhalation Data in Laboratory Animals......................................................9 

TABLE 4. AEGL-1 Values for Tellurium Hexafluoride ...........................................................................12 

TABLE 5. AEGL-2 Values for Tellurium Hexafluoride ...........................................................................13 

TABLE 6. AEGL-3 Values for Tellurium Hexafluoride ...........................................................................14 

TABLE 7. Summary of AEGL Values......................................................................................................14 

TABLE 8. Extant Standards and Guidelines for Tellurium Hexafluoride................................................15
TELLURIUM HEXAFLUORIDE Proposed: April 2009 

6

1 

2 

3 

4 

5 

6 

7 

8 

9 

10 

11 

12 

13 

14 

15 

16 

17 

18 

19 

20 

21 

22 

23 

24 

25 

26 

27 

28 

29 

30 

31 

32 

33 

34 

35 

36 

EXECUTIVE SUMMARY 

Tellurium hexafluoride is a by-product of ore refining. It is a colorless gas with a repulsive 

odor. It decomposes slowly in water to form hydrogen fluoride and tellurium ion. It is severely 

irritating and causes respiratory distress, pulmonary edema, and death in animals. In humans, it 

is reported to cause “garlic” breath, a metallic taste in the mouth, and fatigue. Inhalation of 

tellurium hexafluoride is expected to cause breathing difficulties in humans. 

AEGL-1 values are not recommended due to insufficient data. Absence of an AEGL-1 value 

does not imply that exposure below the AEGL-2 concentration is without adverse effects. 

In the absence of empirical data, and in accord with AEGL derivation guidelines for 

chemicals with steep dose-response curves, the AEGL-2 values for tellurium hexafluoride were 

set at one-third of the AEGL-3 values (NRC 2001). The steep concentration response is 

evidenced by the fact that rabbits, guinea pigs, rats, and mice exposed to 5, 10, 25, 50, or 100 

ppm tellurium hexafluoride for 4 hr all died. All mice exposed to 5 ppm for 1 hr died. All 

animals exposed to 1 ppm for 1 or 4 hr survived (Kimmerle, 1960). 

The highest concentration causing no mortality in a rabbit, guinea pig, rats, and mice (1 ppm 

for 4 hours) was used to derive AEGL-3 values (Kimmerle 1960). An intraspecies uncertainty 

factor of 3 was applied because tellurium hexafluoride is highly irritating and corrosive, and 

much of the toxicity is likely caused by a direct chemical effect on the tissue; this type of portalof-entry effect is not expected to vary greatly among individuals. An interspecies uncertainty 

factor of 1 was applied because the limited data suggest that the rabbit, guinea pig, rat, and 

mouse are similarly sensitive to the acute effects of tellurium hexafluoride. A modifying factor 

of 10 was applied to account for the potential effects of tellurium and the sparse database. Thus, 

the total adjustment is 30. The concentration-exposure time relationship for many irritant and 

systemically-acting vapors and gases may be described by Cn

 x t = k, where the exponent, n, 

ranges from 0.8 to 3.5 (ten Berge et al., 1986). To obtain conservative and protective AEGL 

values in the absence of an empirically derived chemical-specific scaling exponent, temporal 

scaling was performed using n=3 when extrapolating to shorter time points (10-, 30-, and 60-

min) and n = 1 when extrapolating to longer time points (8 hr) using the Cn

 x t = k equation. 

The calculated values are listed in Table 1 below. 

TABLE 1. Summary of AEGL Values for Tellurium Hexafluoride 

Classification 10-minute 30-minute 1-hour 4-hour 8-hour Endpoint (Reference) 

AEGLB1a 

(Nondisabling) NR NR NR NR NR Not recommended due 

to insufficient data 

AEGLB2 

(Disabling) 

0.032 ppm 

(0.32 mg/m3

) 

0.022 ppm 

(0.22 mg/m3)

0.018 ppm 

(0.18 mg/m3)

0.011 ppm 

(0.11 mg/m3) 

0.0057 ppm 

(0.056 mg/m3) 

One-third of the AEGL3 values (NRC 2001) 

AEGLB3 

(Lethal) 

0.096 ppm 

(0.95 mg/m3

) 

0.067 ppm 

(0.66 mg/m3)

0.053 ppm 

(0.52 mg/m3)

0.033 ppm 

(0.33 mg/m3) 

0.017 ppm 

(0.17 mg/m3) 

Highest concentration 

causing no mortality in a 

rabbit, guinea pig, rats, 

and mice (1 ppm, 4-hr) 

(Kimmerle, 1960) 

NR =AEGL-1 values are not recommended due to insufficient data. Absence of an AEGL-1 value does not imply that exposure below the AEGL2 concentration is without adverse effects. 37 

38 

39 

40 
TELLURIUM HEXAFLUORIDE Proposed: April 2009 

7

1 

2 

3 

4 

5 

6 

7 

8 

1. INTRODUCTION 

Tellurium hexafluoride is a colorless gas created by the direct fluorination of tellurium metal 

(HSDB 2005). It hydrolyzes slowly in water to hydrogen fluoride and telluric acid. There are no 

known uses; it is a by-product of ore refining (ACGIH 1991; HSDB 2005). Production data 

were not located. The chemical and physical properties are listed in Table 2. 

TABLE 2. Chemical and Physical Properties 

Parameter Value References 

Synonyms Tellurium fluoride (TeF6), (OC-6-11); 

Tellurium fluoride (TeF6) HSDB 2005 

Chemical formula Te F6 O’Neil 2001

Molecular weight 241.6 O’Neil 2001 

CAS Reg. No. 7783-80-4 O’Neil 2001

Physical state Gas-colorless O’Neil 2001 

Solubility in water Decomposes slowly in water ACGIH 1991; HSDB 2005

Vapor pressure 760 torr at 20oC ACGIH 1991 

Vapor density (air =1) 8.3 HSDB 2005 

Liquid density (water =1) Not applicable - 

Melting point -37.6oC O’Neil 2001

Boiling point -38.9oC ACGIH 1991

Flammability limits Nonflammable gas NIOSH 2005 

Conversion factors 1 ppm = 9.88 mg/m3

1 mg/m3

 = 0.10 ppm 

NIOSH 2005 

9 

10 

11 

12 

13 

14 

15 

16 

17 

18 

19 

20 

21 

22 

23 

24 

25 

26 

27 

28 

29 

30 

31 

32 

33 

2. HUMAN TOXICITY DATA 

2.1. Acute Lethality 

No data were located. 

2.2. Nonlethal Toxicity 

2.2.1. Odor Threshold/Odor Awareness 

 Tellurium hexafluoride has a repulsive odor (O’Neil et al. 2001). 

2.2.2. Case Reports 

 Blackadder and Manderson (1975) reported a case of tellurium hexafluoride exposure. Two 

males, aged 24 and 26 years old, were exposed when 50 g of tellurium hexafluoride gas leaked 

from a cylinder while they were doing research. The first male experienced tiredness, a metallic 

taste in the mouth, and sour garlic odor in his breath, sweat, and urine. He was admitted to the 

hospital for observation and developed a rash on the hands, arms, and neck after the second day 

of observation. He also developed bluish-black patches between the fingers and on the neck and 

face which took several weeks to fade. The second man experienced garlic odor of the breath 

and bluish-black patches on the skin. Liver function tests, renal function tests, urinalysis, chest 

radiographs, blood electrolytes, and blood indices were all normal. The men were not treated 

and both completely recovered with the garlic odor and blue-black patches taking several weeks 

to clear. The blue-black patches were thought to be the result of dermal absorption of tellurium. 
TELLURIUM HEXAFLUORIDE Proposed: April 2009 

8

1 

2 

3 

4 

5 

6 

7 

8 

9 

10 

11 

12 

13 

14 

15 

16 

17 

18 

19 

20 

21 

22 

23 

24 

25 

26 

27 

28 

29 

30 

31 

32 

33 

34 

35 

36 

37 

38 

2.3. Neurotoxicity 

 No data were located. 

2.4. Developmental/Reproductive Toxicity 

 No data were located. 

2.5. Genotoxicity 

 No data were located. 

2.6. Carcinogenicity 

 No data were located. 

2.7. Summary 

 Human exposure to tellurium hexafluoride caused metallic taste in mouth, tiredness, sour 

garlic odor in the breath, sweat, and urine, and bluish-black patches on the skin. Tellurium 

hexafluoride is a respiratory irritant and humans may experience breathing difficulties following 

inhalational exposure (NIOSH 1978; OSHA 1996). 

3. ANIMAL TOXICITY DATA 

3.1. Acute Lethality 

 Kimmerle (1960) exposed one rabbit, one guinea pig, two male white rats, and four male 

white mice per group to tellurium hexafluoride for 1 or 4 hours. Exposures were carried out in a 

2 cubic meter chamber and the tellurium hexafluoride was introduced into the chamber through a 

glass burette and mixed with air by a propeller. The animals were exposed to 1 or 5 ppm 

(nominal concentrations) tellurium hexafluoride for 1 hour and 1, 5, 10, 25, 50 or 100 ppm 

(nominal concentrations) tellurium hexafluoride for 4 hour. At 5 ppm for 1 hour, severe damage 

was observed in the respiratory organs of the animals, and all mice died between 24 and 36 hour, 

but all animals survived at 1 ppm for 1 hour. Exposure to 1 ppm for 4 hr caused respiratory 

dysfunction in all animals. All animals died after exposure to 5, 10, 25, 50, or 100 ppm for 4 

hour. Death was caused by pulmonary edema. 
TELLURIUM HEXAFLUORIDE Proposed: April 2009 

9

1 TABLE 3. Summary of Acute Inhalation Data in Laboratory Animals 

Species Concentration 

(ppm) 

Exposure 

Time (hr) Effect Reference 

Rabbit 

1 

5 

10 

25 

50 

100 

4 

Respiratory dysfunction, pulmonary edema 

Death at 8 hours 

Death at 140 min 

Death at 80 min 

Death at 60 min 

Death at 15 min 

Kimmerle 1960 

Rabbit 1 

5 1 Significantly increased respiratory frequency Severe damage to respiratory organs Kimmerle 1960 

Guinea Pig 

1 

5 

10 

25 

50 

100 

4 

Respiratory dysfunction, pulmonary edema 

Death at 6 hours 

Death at 120 min 

Death at 100 min 

Death at 70 min 

Death at 30 min 

Kimmerle 1960 

Guinea Pig 1 

5 1 Significantly increased respiratory frequency Severe damage to respiratory organs Kimmerle 1960 

Rat 

1 

5 

10 

25 

50 

100 

4 

Respiratory dysfunction, pulmonary edema 

Death at 6 and 24 hours 

Death at 100 and 115 min 

Death at 60 and 85 min 

Death at 55 and 70 min 

Death at 20 and 25 min 

Kimmerle 1960 

Rat 1 

5 1 Significantly increased respiratory frequency Severe damage to respiratory organs Kimmerle 1960 

Mouse 

1 

5 

10 

25 

50 

100 

4 

Respiratory dysfunction, pulmonary edema 

Death within 4-24 hours 

Death within 110-130 min 

Death within 75-110 min 

Death within 45-70 min 

Death within 10-30 min 

Kimmerle 1960 

Mouse 1 

5 1 

Significantly increased respiratory frequency 

Death between 24-36 hours, severe damage to 

respiratory organs 

Kimmerle 1960 

2 

3 

4 

5 

6 

7 

8 

9 

10 

11 

12 

13 

14 

15 

16 

17 

18 

19 

3.2. Nonlethal Toxicity 

 Kimmerle (1960) exposed one rabbit, one guinea pig, two male white rats, and four male 

white mice per group to 1 or 5 ppm tellurium hexafluoride for 1 or 4 hours as described in 

section 3.1. Significantly increased respiratory frequency (hyperpnea) was observed in all 

animals exposed to 1 ppm for 1 hour. At 5 ppm for 1 hour, severe damage was observed in the 

respiratory organs of the animals, and the rabbit, guinea pigs, and rats survived the exposure but 

recovered very slowly. Exposure to 1 ppm for 4 hours caused respiratory dysfunction in all 

animals. Kimmerle also exposed the same set of test animals to 1 ppm for 1 hour each day for 

five days and found no visible effects in the animals. In the rabbit, liver function tests were 

carried out after the end of the repeat-exposure test and again one week later. No liver damage 

was observed. 

3.3. Developmental/Reproductive Toxicity 

No data were located. 
TELLURIUM HEXAFLUORIDE Proposed: April 2009 

10

1 

2 

3 

4 

5 

6 

7 

8 

9 

10 

11 

12 

13 

14 

15 

16 

17 

18 

19 

20 

21 

22 

23 

24 

25 

26 

27 

28 

29 

30 

31 

32 

33 

34 

35 

36 

37 

38 

39 

40 

41 

42 

43 

44 

45 

46 

47 

48 

3.4. Genotoxicity 

 No data were located. 

3.5. Chronic Toxicity/Carcinogenicity 

 No data were located. 

3.5. Summary 

 Only one study that addressed tellurium hexafluoride toxicity in animal models was located. 

Kimmerle (1960). Rabbits, guinea pigs, rats, and mice exposed to 5, 10, 25, 50, or 100 ppm 

tellurium hexafluoride for 4 hours all died. All mice exposed to 5 ppm for 1 hour died; whereas, 

animals exposed to 1 ppm for 1 hour survived. Repeated exposure to 1 ppm 1 hour/day for 5 

days resulted in no clinical signs or mortality in any species tested. Clinical signs (respiratory 

distress) and post-mortem findings (pulmonary edema) were consistent with severe irritation in 

all animals except those exposed to 1 ppm for 1 hour who exhibited hyperpnea. No data on 

developmental/ reproductive toxicity, genotoxicity, or chronic toxicity/carcinogenicity were 

located. 

4. SPECIAL CONSIDERATIONS 

4.1. Metabolism and Disposition 

 Little information was located concerning the metabolism and disposition of tellurium 

hexafluoride. However, tellurium hexafluoride may be hydrolyzed in the moist respiratory tract 

to hydrogen fluoride and the tellurium ion or telluric acid (HSDB 2005). Tellurium is distributed 

through the body. In the liver, hepatic metabolism creates dimethyl telluride which is exhaled as 

a garlic odor in the breath (IPCS 1998). 

4.2. Mechanism of Toxicity 

 In the moist respiratory tract, it is believed that tellurium hexafluoride slowly hydrolyzes into 

hydrogen fluoride and tellurium ion or telluric acid. Kimmerle (1960) has shown that the toxic 

effects of inhaled tellurium hexafluoride are consistent with severe irritation/corrosivity. 

Hydrogen fluoride is a severe irritant to the skin, eyes, and respiratory tract. The AEGL values 

for hydrogen fluoride, however, are orders of magnitude higher than the AEGL values for 

tellurium hexafluoride which may indicate hydrogen fluoride does not play a major role in its 

toxicity. Penetration of hydrogen fluoride to the lungs produces pulmonary hemorrhage and 

edema and may result in death (NRC 2004). The mechanism of toxicity of tellurium is 

unknown. It has been shown that tellurium inhibits squalene epoxidase which may interfere with 

neurotransmission through demyelination. This has been observed in young animals but not in 

humans (Anthony et al. 2001). 

 

4.3. Structure Activity Relationships 

 Tellurium hexafluoride is analogous to selenium hexafluoride in molecular structure and 

noble gas configuration. Both are irritating gases that cause pulmonary edema and death. 

Tellurium hexafluoride was found to be more toxic in laboratory animals than selenium 
TELLURIUM HEXAFLUORIDE Proposed: April 2009 

11

1 

2 

3 

4 

5 

6 

7 

8 

9 

10 

11 

12 

13 

14 

15 

16 

17 

18 

19 

20 

21 

22 

23 

24 

25 

26 

27 

28 

29 

30 

31 

32 

33 

34 

35 

36 

37 

38 

39 

40 

41 

42 

43 

44 

45 

46 

47 

48 

hexafluoride (Kimmerle 1960). All rabbits, guinea pigs, rats, and mice exposed to 10 ppm 

selenium hexafluoride for 4 hours died while those exposed to 5 or 1 ppm selenium hexafluoride 

survived the exposure. Animals exposed to 5 ppm selenium hexafluoride exhibited difficulty 

breathing and pulmonary edema, which resolved during the follow-up period. No effects were 

observed in animals exposed to 1 ppm selenium hexafluoride. All rabbits, guinea pigs, rats, and 

mice exposed to 5 ppm tellurium hexafluoride for 4 hours died while those exposed to 1 ppm 

tellurium hexafluoride survived the exposure. Those exposed to 1 ppm tellurium hexafluoride 

exhibited difficulty breathing and pulmonary edema, which resolved during the follow-up 

period. 

 Because one mole of tellurium hexafluoride may decompose in moist atmospheres to form 

up to 6 moles of hydrogen fluoride, it might be assumed that tellurium hexafluoride may be 

approximately six times more toxic than hydrogen fluoride on a molar basis. However, the 

limited data set suggests that tellurium hexafluoride is much more than six times as toxic as 

hydrogen fluoride. 

The of one-hour LC50 values for hydrogen fluoride for the mouse ranges from 342 to 501 

ppm (NRC 2004). If the acute inhalation toxicity of tellurium hexafluoride was due only to the 

hydrogen fluoride hydrolysis product, then approximate 1-hour LC50 values for tellurium 

hexafluoride would range from 57-84 ppm for mice. However, 4/4 mice died when exposed to 

only 5 ppm tellurium hexafluoride for 1 hour (Kimmerle, 1960). The increased relative toxicity 

of tellurium hexafluoride may be due to the tellurium moiety and the slow hydrolysis rate of 

tellurium hexafluoride. 

4.4. Other Relevant Information 

 No additional relevant information was located. 

4.4.1. Species Variability 

The limited data of Kimmerle (1960) suggest that the acute toxicity of tellurium hexafluoride 

is similar among rabbits, guinea pigs, rats, and mice. Mice may be slightly more sensitive as 

indicated by the death of all mice (n=4) at 5 ppm for 1 hour. This would be expected for a 

corrosive/severely irritating chemical. 

4.4.2. Susceptible Populations 

No information was available on populations especially sensitive to tellurium hexafluoride 

toxicity. However, the steep concentration-response curve implies limited intraspecies 

variability. Rabbits, guinea pigs, rats, and mice exposed to 5, 10, 25, 50, or 100 ppm tellurium 

hexafluoride for 4 hours all died. All mice exposed to 5 ppm for 1 hour died; whereas, animals 

exposed to 1 ppm for 1-hour survived (Kimmerle 1960). 

Individuals with impaired pulmonary function might respond to exposure to tellurium 

hexafluoride with exacerbation of symptoms due to its irritant properties (NIOSH 1978). No 

information on the relative susceptibility of individuals with impaired pulmonary function and 

normal individuals to tellurium hexafluoride was located. 
TELLURIUM HEXAFLUORIDE Proposed: April 2009 

12

1 

2 

3 

4 

5 

6 

7 

8 

9 

10 

11 

12 

13 

14 

15 

16 

17 

18 

19 

20 

21 

22 

23 

24 

25 

26 

27 

4.4.3. Concentration-Exposure Duration Relationship 

The concentration exposure time relationship for many irritant and systemically acting 

vapors and gases may be described by Cn x t = k, where the exponent ranges from 0.8 to 3.5 (ten 

Berge et al. 1986). In lieu of a definitive data set allowing empirical derivation of the exponent 

n, temporal scaling was performed, using n = 3 when extrapolating to shorter time points and n = 

1 when extrapolating to longer time points using the Cn x t = k equation (NRC 2001). 

4.4.4. Concurrent Exposure Issues 

 No concurrent exposure issues were identified. 

5. DATA ANALYSIS FOR AEGL-1 

5.1. Summary of Human Data Relevant to AEGL-1 

 No human data relevant to development of AEGL-1 values were identified. 

5.2. Summary of Animal Data Relevant to AEGL-1 

 No animal data relevant to development of AEGL-1 values were identified. 

5.3. Derivation of AEGL-1 

AEGL-1 values are not recommended due to insufficient data. Absence of an AEGL-1 value 

does not imply that exposure below the AEGL-2 concentration is without adverse effects. 

 

TABLE 4. AEGL-1 Values for Tellurium Hexafluoride 

10-minute 30-minute 1-hour 4-hour 8-hour 

NR NR NR NR NR) 

NR =AEGL-1 values are not recommended due to insufficient data. Absence of an AEGL-1 value does not imply that exposure below the AEGL2 concentration is without adverse effects. 28 

29 

30 

31 

32 

33 

34 

35 

36 

37 

38 

39 

40 

41 

42 

43 

44 

6. DATA ANALYSIS FOR AEGL-2 

6.1. Summary of Human Data Relevant to AEGL-2 

 No human data relevant to development of AEGL-2 values were identified. 

6.2. Summary of Animal Data Relevant to AEGL-2 

Kimmerle (1960) exposed one rabbit, one guinea pig, two male white rats, and four male 

white mice per group to 1 or 5 ppm tellurium hexafluoride for 1 or 4 hours. Hyperpnea was 

observed in all animals exposed to 1 ppm for 1 hour. At 5 ppm for 1 hour, severe damage was 

observed in the respiratory organs of the animals, and the rabbit, guinea pigs, and rats survived 

the exposure but recovered very slowly; all the mice died. Exposure to 1 ppm for 4 hours caused 

respiratory dysfunction in all animals. 
TELLURIUM HEXAFLUORIDE Proposed: April 2009 

13

1 

2 

3 

4 

5 

6 

7 

8 

9 

10 

11 

12 

6.3. Derivation of AEGL-2 

The data available are not consistent with AEGL-2 severity effects. Animals experienced 

hyperpnea from exposure to 1 ppm tellurium hexafluoride for 1 hour. In the absence of 

empirical data, and in accord with AEGL derivation guidelines for chemicals with steep doseresponse curves, the AEGL-2 values for tellurium hexafluoride were set at one-third of the 

AEGL-3 values (NRC 2001). Rabbits, guinea pigs, rats, and mice exposed to 5, 10, 25, 50, or 

100 ppm tellurium hexafluoride for 4 hours all died. Animals exposed to 1 ppm for 4 hours 

survived. AEGL-2 values are presented in Table 5, and calculations are presented in Appendix 

A.

TABLE 5. AEGL-2 Values for Tellurium Hexafluoride 

10-minute 30-minute 1-hour 4-hour 8-hour 

0.032 ppm 

(0.32 mg/m3

) 

0.022 ppm 

(0.22 mg/m3) 

0.018 ppm 

(0.18 mg/m3) 

0.011 ppm 

(0.11 mg/m3) 

0.0057 ppm 

(0.056 mg/m3) 

13 

14 

15 

16 

17 

18 

19 

20 

21 

22 

23 

24 

25 

26 

27 

28 

29 

30 

31 

32 

33 

34 

35 

36 

37 

38 

39 

40 

41 

42 

43 

44 

7. DATA ANALYSIS FOR AEGL-3 

7.1. Summary of Human Data Relevant to AEGL-3 

No human data relevant to development of AEGL-3 values were identified. 

7.2. Summary of Animal Data Relevant to AEGL-3 

 Rabbits, guinea pigs, rats, and mice exposed to 5, 10, 25, 50, or 100 ppm tellurium 

hexafluoride for 4 hours died (Kimmerle 1960). All mice exposed to 5 ppm for 1 hour died; the 

remaining animals recovered very slowly from severe damage to the respiratory organs. The 

same animals exposed to 1 ppm for 4 hours survived but experienced pulmonary edema and 

respiratory dysfunction. Animals exposed to 1 ppm for 1 hr experienced hyperpnea but survived. 

7.3. Derivation of AEGL-3 

The highest concentration causing no mortality in the rabbit, guinea pig, rats, and mice (1 

ppm for 4 hours) was used to derive AEGL-3 values (Kimmerle 1960). An intraspecies 

uncertainty factor of 3 was applied because tellurium hexafluoride is highly irritating and 

corrosive, and much of the toxicity is likely caused by a direct chemical effect on the tissue; this 

type of portal-of-entry effect is not expected to vary greatly among individuals. The steep 

concentration-response curve implies limited intra-individual variability. Rabbits, guinea pigs, 

rats, and mice exposed to 5, 10, 25, 50, or 100 ppm tellurium hexafluoride for 4 hours all died. 

Animals exposed to 1 ppm for 4 hours survived (Kimmerle 1960). An interspecies uncertainty 

factor of 1 was applied because the limited data suggest that the rabbit, guinea pig, rat, and 

mouse are similarly sensitive to the acute effects of tellurium hexafluoride. A modifying factor 

of 10 was also applied to account for the potential effects of tellurium and the sparse database. 

Thus, the total adjustment is 30. The concentration-exposure time relationship for many irritant 

and systemically-acting vapors and gases may be described by Cn

 x t = k, where the exponent, n, 

ranges from 0.8 to 3.5 (ten Berge et al., 1986). To obtain conservative and protective AEGL 

values in the absence of an empirically derived chemical-specific scaling exponent, temporal 

scaling was performed using n=3 when extrapolating to shorter time points (10-, 30-, and 6-min) 
TELLURIUM HEXAFLUORIDE Proposed: April 2009 

14

1 

2 

3 

4 

and n = 1 (8 hr) when extrapolating to longer time points using the Cn

 x t = k equation. AEGL-3 

values are presented in Table 6, and calculations are presented in Appendix A. 

TABLE 6. AEGL-3 Values for Tellurium Hexafluoride 

10-minute 30-minute 1-hour 4-hour 8-hour 

0.096 ppm 

(0.95 mg/m3

) 

0.067 ppm 

(0.66 mg/m3) 

0.053 ppm 

(0.52 mg/m3) 

0.033 ppm 

(0.33 mg/m3) 

0.017 ppm 

(0.17 mg/m3) 

5 

6 

7 

8 

9 

10 

11 

12 

13 

14 

15 

16 

17 

18 

19 

20 

21 

22 

23 

24 

25 

26 

Although AEGL-3 values were derived from a 4-hour time point, the 30-minute value was 

not adopted for the 10-minute value. The 10-minute value was calculated from the 4-hour time 

point and this approach is supported by the 1 hour study in multiple species were exposed to 1 

ppm (Kimmerle 1960). This exposure resulted in hyperpnea in all animals, a non life-threatening 

endpoint. Extrapolating that value and applying the total adjustment (uncertainty and modifying 

factor) of 30 yields a value of 2 ppm-min, suggesting that the proposed AEGL-3 10-minute value 

(0.097 ppm x 10 min = 0.97 ppm-min) is protective. 

8. SUMMARY OF AEGLS 

8.1. AEGL Values and Toxicity Endpoints 

AEGL values are summarized in Table 7. AEGL-1 values are not recommended due to 

insufficient data. AEGL-2 values are based on a three fold reduction of the AEGL-3 values 

because experimental data were not available to empirically derive AEGL-2 values and the steep 

exposure concentration response curve evidenced by the fact that rabbits, guinea pigs, rats, and 

mice exposed to 5, 10, 25, 50, or 100 ppm tellurium hexafluoride for 4 hours all died. All mice 

exposed to 5 ppm for 1 hour died. All animals exposed to 1 ppm for 1 or 4 hours survived. 

AEGL-3 values were based on the highest concentration causing no deaths in a rabbit, a guinea 

pig, rats, and mice (1 ppm for 4 hour) (Kimmerle 1960). 

TABLE 7. Summary of AEGL Values 

Exposure Duration Classification 

10-minute 30-minute 1-hour 4-hour 8-hour 

AEGL-1 

(Nondisabling) NR NR NR NR NR 

AEGL-2 

(Disabling) 

0.032 ppm 

(0.32 mg/m3

) 

0.022 ppm 

(0.22 mg/m3) 

0.018 ppm 

(0.18 mg/m3) 

0.011 ppm 

(0.11 mg/m3) 

0.0057 ppm 

(0.056 mg/m3) 

AEGL-3 

(Lethal) 

0.096 ppm 

(0.95 mg/m3

) 

0.067 ppm 

(0.66 mg/m3) 

0.053 ppm 

(0.52 mg/m3) 

0.033 ppm 

(0.33 mg/m3) 

0.017 ppm 

(0.17 mg/m3) 

NR =AEGL-1 values are not recommended due to insufficient data. Absence of an AEGL-1 value does not imply that exposure below the AEGL2 concentration is without adverse effects. 27 

28 

29 

30 

31 

32 

33 

34 

35 

36 

37 

8.2. Comparison with Other Standards and Guidelines 

AEGL values for tellurium hexafluoride are compared to other guidelines and standards for 

this compound in Table 8. The time-weighted average exposure concentration for workers is set 

at 0.02 ppm (ACGIH 2008; NIOSH 2005; OSHA 2005). The ACGIH TLV-TWA was set at 

0.02 ppm (measured as tellurium) on the basis that tellurium hexafluoride is approximately 2.5 

times as acutely toxic as ozone and to protect against respiratory effects (ACGIH 1991). The 

IDLH (NIOSH 1996) was based on acute inhalation toxicity data from Kimmerle (1960). 
TELLURIUM HEXAFLUORIDE Proposed: April 2009 

15

1 

2 TABLE 8. Extant Standards and Guidelines for Tellurium Hexafluoride 

Exposure Duration Guideline 

10 minute 30 minute 1 hour 4 hour 8 hour 

AEGL-1 NR NR NR NR NR 

AEGL-2 0.032 ppm 

(0.32 mg/m3

) 

0.022 ppm 

(0.22 mg/m3) 

0.018 ppm 

(0.18 mg/m3) 

0.011 ppm 

(0.11 mg/m3) 

0.0057 ppm 

(0.056 mg/m3) 

AEGL-3 0.096 ppm 

(0.95 mg/m3

) 

0.067 ppm 

(0.66 mg/m3) 

0.053 ppm 

(0.52 mg/m3) 

0.033 ppm 

(0.33 mg/m3) 

0.017 ppm 

(0.17 mg/m3) 

PEL-TWA 

(OSHA)a 0.02 ppm 

IDLH (NIOSH)b 1 ppm 

REL-TWA 

(NIOSH)c 0.02 ppm 

TLV-TWA 

(ACGIH)d 0.02 ppm 

MAC-Peak 

Category (The 

Netherlands)e

0.02 ppm 

NR =AEGL-1 values are not recommended due to insufficient data. Absence of an AEGL-1 value does not imply that exposure below the AEGL2 concentration is without adverse effects. 3 

4 

5 

6 

7 

8 

9 

10 

11 

12 

13 

14 

15 

16 

17 

18 

19 

20 

21 

22 

23 

24 

25 

26 

27 

28 

29 

30 

31 

a

 OSHA PEL-TWA (Occupational Health and Safety Administration, Permissible Exposure Limits - Time Weighted Average) 

(OSHA 2005) is defined analogous to the ACGIH-TLV-TWA, but is for exposures of no more than 10 hours/day, 40 

hours/week. 

b

 IDLH (Immediately Dangerous to Life and Health, National Institute of Occupational Safety and Health) (NIOSH 1996) 

represents the maximum concentration from which one could escape within 30 minutes without any escape-impairing 

symptoms, or any irreversible health effects. 

c

 NIOSH REL-TWA (National Institute of Occupational Safety and Health, Recommended Exposure Limits - Time Weighted 

Average) (NIOSH 2005) is defined analogous to the ACGIH-TLV-TWA. 

d

 ACGIH TLV-TWA (American Conference of Governmental Industrial Hygienists, Threshold Limit Value - Time Weighted 

Average) (ACGIH 2008) is the time-weighted average concentration for a normal 8-hour workday and a 40-hour work 

week, to which nearly all workers may be repeatedly exposed, day after day, without adverse effect 

e MAC (Maximaal Aanvaaarde Concentratie [Maximal Accepted Concentration - Peak Category]) (SDU Uitgevers 

[under the auspices of the Ministry of Social Affairs and Employment], The Hague, The Netherlands 2000) is defined 

analogous to the ACGIH-Ceiling 

8.3. Data Adequacy and Research 

There are no quantitative human data, and animal data are limited. A single study that 

addressed acute toxicity of tellurium hexafluoride in a limited number of rabbits, guinea pigs, 

rats, and mice was available (Kimmerle 1960). It is believed that in the moist respiratory tract, 

tellurium hexafluoride slowly breaks down into hydrogen fluoride and tellurium. Additional 

acute inhalation toxicity studies would be helpful. 
TELLURIUM HEXAFLUORIDE Proposed: April 2009 

16

1 

2 

3 

4 

5 

6 

7 

8 

9 

10 

11 

12 

13 

14 

15 

16 

17 

18 

19 

20 

21 

22 

23 

24 

25 

26 

27 

28 

29 

30 

31 

32 

33 

34 

35 

36 

37 

38 

39 

40 

41 

42 

43 

44 

45 

46 

47 

48 

9. REFERENCES 

ACGIH (American Conference of Governmental Industrial Hygienists). 1991. Documentation 

of the Threshold Limit Values and Biological Exposure Indices: Tellurium Hexafluoride. 

Sixth ed., ACGIH, Cincinnati, OH. 

ACGIH (American Conference of Governmental Industrial Hygienists). 2008. Threshold limit 

values (TLVs) for chemical and physical agents and biological exposure indices (BEIs). 

ACGIH, Cincinnati, OH. 

Anthony, D.C., T.J. Montine, W.M. Valentine, and D.G. Graham. 2001. Toxic Responses of the 

Nervous System. Casarett & Doull’s Toxicology: The Basic Science of Poisons, 6th Ed., C.D. 

Klaassen, ed. New York: McGraw-Hill. p.554. 

Blackadder, E.S. and W.G. Manderson. 1975. Occupational absorption of tellurium: a report of 

two cases. Br. J. Ind. Med. 32: 59-61. 

HSDB (Hazardous Substances Data Bank). 2005. Tellurium Hexafluoride. [Online] Available. 

http://toxnet.nlm.nih.gov/ [02/197/2008]. TOXNET, Toxicology Data Network. US. Natl. 

Library of Medicine. 

IPCS (International Programme on Chemical Safety). 1998. Tellurium Hexafluoride. UKPID 

Monograph. [Online] Available. http://www.intox.org/databank.documents/chemical/ 

telhexaf/ukpif83.htm [01/07/2009]. 

Kimmerle, G. 1960. [Comparative studies on the inhalation toxicity of sulfur-, selenium-, and 

tellurium –hexafluoride]. Arch. Toxikol. 18: 140-144. 

NIOSH (National Institute for Occupational Safety and Health). 1978. Occupational Health 

Guideline for Tellurium Hexafluoride. [Online] Available. http://www.cdc.gov/niosh/pdfs/ 

0588.pdf [02/04/2009]. 

NIOSH (National Institute for Occupational Safety and Health). 1996. Documentation for 

Immediately Dangerous to Life and Health Concentrations (IDLH). [Online] Available. 

http://www.cdc.gov/niosh/idlh/ [09/10/2006]. 

NIOSH (National Institute for Occupational Safety and Health). 2005. NIOSH Pocket Guide to 

Chemical Hazards- Tellurium hexafluoride. NIOSH, Cincinnati, OH. [Online] Available. 

http://www.cdc.gov/niosh/ [04/14/2008]. 

NRC (National Research Council). 2004. Acute Exposure Guideline Levels for Selected 

Airborne Chemicals, Volume 4: Hydrogen Fluoride, pp. 123-197. The National Academies 

Press, Washington, DC. 

NRC (National Research Council). 2001. Standing Operating Procedures for Developing Acute 

Exposure Guideline Levels for Hazardous Chemicals. The National Academies Press, 

Washington, DC. 
TELLURIUM HEXAFLUORIDE Proposed: April 2009 

17

1 

2 

3 

4 

5 

6 

7 

8 

9 

10 

11 

12 

13 

14 

15 

16 

17 

18 

19 

20 

O’Neil, M.J., Smith, A., Heckelman, P.E. eds. 2001. The Merck Index, 13th ED. Whitehouse 

Station, NJ: Merck and Co. 3984. 

OSHA (Occupational Safety and Health Administration). 1996. Occupational Safety and Health 

Guideline for Tellurium Hexafluoride. [Online] Available. http://www.osha.gov/SLTC/ 

healthguidelines/telluriumhexafluoride/recognition.html [02/04/2009]. 

OSHA (Occupational Safety and Health Administration). 2005. Code of Federal Regulations, 

CFR 29, Part 1910, Table Z-1. 

SDU Uitgevers 2000. MAC Ministry of Social Affairs and Employment. Nationale MAC 

(Maximum Allowable Concentration) List, 2000. The Hague, The Netherlands. 

ten Berge, W.F., A. Zwart, and L.M. Appelman. 1986. Concentration-time mortality response 

relationship of irritant and systemically acting vapours and gases. J. Hazard. Materials: 13: 

301-309. 
TELLURIUM HEXAFLUORIDE Proposed: April 2009 

18

1 

2 

3 

4 

5 

6 

7 

8 

9 

10 

11 

12 

13 

14 

15 

16 

17 

18 

19 

20 

21 

APPENDIX A: Derivation of AEGL Values

Derivation of AEGL-1 

Key Study: AEGL-1 values are not recommended due to insufficient data. Absence of an AEGL1 value does not imply that exposure below the AEGL-2 concentration is without adverse 

effects. 

Calculations: 

10-minute AEGL-1 NR 

30-minute AEGL-1 NR 

1-hour AEGL-1 NR 

4-hour AEGL-1 NR 

8-hour AEGL-1 NR 
TELLURIUM HEXAFLUORIDE Proposed: April 2009 

19

1 

2 

3 

4 

5 

6 

7 

8 

9 

10 

11 

12 

13 

14 

15 

16 

17 

18 

19 

20 

21 

22 

23 

24 

25 

26 

27 

28 

29 

Derivation of AEGL-2 

Key Studies: Kimmerle, G. 1960. [Comparative studies on the inhalation toxicity of 

sulfur-, selenium-, and tellurium –hexafluoride]. Arch. Toxikol. 18: 140-

144. 

Toxicity endpoints: In the absence of empirical data, and in accord with AEGL derivation 

guidelines for chemicals with steep dose-response curves, the AEGL-2 

values for tellurium hexafluoride were set at one-third of the AEGL-3 

values (NRC 2001). Rabbits, guinea pigs, rats, and mice exposed to 5, 10, 

25, 50, or 100 ppm tellurium hexafluoride for 4 hours all died. All mice 

exposed to 5 ppm for 1 hour died. All animals exposed to 1 ppm for 1 or 

4 hours survived. 

Calculations: 

10-minute AEGL-2 0.096 ppm/3 = 0.032 ppm 

30-minute AEGL-2 0.067 ppm/3 = 0.022 ppm 

1-hour AEGL-2 0.053 ppm/3 = 0.018 ppm 

4-hour AEGL-2 0.033 ppm/3 = 0.011 ppm 

8-hour AEGL-2 0.017 ppm/3 = 0.0057 ppm 
TELLURIUM HEXAFLUORIDE Proposed: April 2009 

20

1 

2 

3 

4 

5 

6 

7 

8 

9 

10 

11 

12 

13 

14 

15 

16 

17 

18 

19 

20 

21 

22 

23 

24 

25 

26 

27 

28 

29 

30 

31 

32 

33 

34 

35 

36 

37 

38 

39 

40 

41 

42 

43 

Derivation of AEGL-3 

Key Studies: Kimmerle, G. 1960. [Comparative studies on the inhalation toxicity of 

sulfur-, selenium-, and tellurium –hexafluoride]. Arch. Toxikol. 18: 140-

144. 

Toxicity endpoint: Highest concentration causing no mortality in the guinea pig, rabbit, rat, 

and mouse (1 ppm for 4-hours) 

Uncertainty factors: Interspecies: 1, limited data suggest that the guinea pig, rabbit, rat, and 

mouse are similarly sensitive to the acute effects of tellurium hexafluoride 

 

Intraspecies: 3, tellurium hexafluoride is highly irritating and corrosive, 

and much of the toxicity is likely caused by a direct chemical effect on the 

tissues; this type of portal-of-entry effect is not expected to vary greatly 

among individuals. 

Modifying factor: 10: potential effects of tellurium and sparse database 

Time scaling: 1 ppm /30 = 0.0333333 ppm 

C3

 x t = k (10- min, 30-min, 60-min) 

(0.0333333 ppm) 3 x 240 min = 0.0088888622 ppm3-min 

C1 x t = k (4-hr, 8-hr) 

0.0333333 ppm 1 x 240 min = 7.999992 ppm-min 

10-minute AEGL-3 C3

 x 10 minutes = 0.0088888622 ppm3·min 

 C = 0.096 ppm 

30-minute AEGL-3: C3

 x 30 minutes = 0.0088888622 ppm3·min 

 C = 0.067 ppm 

1-hour AEGL-3: C3

 x 30 minutes = 0.0088888622 ppm3·min 

 C = 0.053 ppm 

4-hour AEGL-3: C1

 x 240 minutes = 7.999992 ppm·min 

 C = 0.033 ppm 

8-hour AEGL-3: C1

 x 480 minutes = 7.999992 ppm·min 

 C = 0.017 ppm 
TELLURIUM HEXAFLUORIDE Proposed: April 2009 

21

1 

2 

3 

4 

5 

6 

7 

APPENDIX B: Derivation Summary for Tellurium Hexafluoride AEGLs 

Acute Exposure Guideline Levels for Tellurium Hexafluoride (CAS Reg. No. 7783-80-4) 

Derivation Summary 

AEGL-1 VALUES 

No AEGL-1 values were derived due to insufficient data 

10-minute 30-minute 1-hour 4-hour 8-hour 

NR NR NR NR NR 

Key Reference: 

Test Species/Strain/Number: 

Exposure Route/Concentrations/Durations: 

Effects: 

Endpoint/Concentration/Rationale: 

Uncertainty Factors/Rationale: 

Total uncertainty factor: 

Interspecies: 

Intraspecies: 

Modifying Factor: 

Animal to Human Dosimetric Adjustment: 

Time Scaling: 

Data Adequacy: 

NR= Not recommended due to insufficient data. Absence of an AEGL-1 value does not imply that exposure below the AEGL 

concentration is without adverse effects.

8 

9 
TELLURIUM HEXAFLUORIDE Proposed: April 2009 

22

1 

2 AEGL-2 VALUES 

10-minute 30-minute 1-hour 4-hour 8-hour 

0.032 ppm 0.022 ppm 0.018 ppm 0.011 ppm 0.0057 ppm 

Key Reference: Kimmerle, G. 1960. [Comparative study of the inhalation toxicity of sulfur, selenium, and 

tellurium hexafluorides.] Arch Toxikol. 18: 140-144. 

Test Species/Strain/Number: Rabbit (1); Guinea pig (1); Rat (2); Mouse (4)/strain not reported 

Exposure Route/Concentrations/Durations: Inhalation/1, 5, 10, 25, 50, 100 ppm/ 4 hr 

Effects: Respiratory dysfunction, pulmonary edema, death 

Endpoint/Concentration/Rationale: In the absence of empirical data, the AEGL-3 values were divided by 3 to 

obtain AEGL-2 values for tellurium hexafluoride. This approach is justified based on a steep concentration 

response curve evidenced by rabbits, guinea pigs, rats, and mice exposed to 5, 10, 25, 50, or100 ppm tellurium 

hexafluoride for 4 hours dying. All mice exposed to 5 ppm for 1 hour died. All animals exposed to 1 ppm for 1 

or 4 hours survived (Kimmerle, 1960). 

Uncertainty Factors/Rationale: See AEGL-3 derivation summary below. 

Modifying Factor: None applied 

Animal to Human Dosimetric Adjustment: None applied 

Time Scaling: See AEGL-3 derivation. 

Data Adequacy: See AEGL-3 derivation 

3 
TELLURIUM HEXAFLUORIDE Proposed: April 2009 

23

1 

2 

3 

4 

AEGL-3 VALUES 

10-minute 30-minute 1-hour 4-hour 8-hour 

0.096 ppm 0.067 ppm 0.053 ppm 0.033 ppm 0.017 ppm 

Key Reference: Kimmerle, G. 1960. [Comparative study of the inhalation toxicity of sulfur, selenium, and 

tellurium hexafluorides.] Arch Toxikol. 18: 140-144. 

Test Species/Strain/Number: Rabbit (1); Guinea pig (1); Rat (2); Mouse (4)/strain not reported 

Exposure Route/Concentrations/Durations: Inhalation/1, 5, 10, 25, 50, 100 ppm/ 4 hr 

Effects: 

 1 ppm Respiratory dysfunction, pulmonary edema

 5 ppm Death from 4-24 hours 

10 ppm Death from 100-140 min 

25 ppm Death from 60-110 min 

50 ppm Death from 45-70 min 

100 ppm Death from 10-30 min 

Endpoint/Concentration/Rationale: Highest concentration causing no mortality/ 1 ppm 

Uncertainty Factors/Rationale: 

Total uncertainty factor: 3 

Interspecies: 1, limited data suggest that the guinea pig, rabbit, rat, and mouse are similarly sensitive to the 

acute effects of tellurium hexafluoride 

Intraspecies: 3, tellurium hexafluoride is highly irritating and corrosive, and much of the toxicity is likely 

caused by a direct chemical effect on the tissues; this type of portal-of-entry effect is not expected to vary 

greatly among individuals. 

Modifying Factor: 10, to account for potential effects of tellurium and the sparse database 

Animal to Human Dosimetric Adjustment: none 

Time Scaling: cn x t = k, where the exponent, n=3 when extrapolating to shorter time points (10,30, 60 min) and 

n = 1 when extrapolating to longer time (8-hr). 

Data Adequacy: Tellurium hexafluoride has a very sparse data base consisting of one lethality study in 

laboratory animals. 

5 
TELLURIUM HEXAFLUORIDE Proposed: April 2009 

24

1 

2 

3 

APPENDIX C: Category Plot for Tellurium Hexafluoride 

0.001 

0.010 

0.100 

1.000 

10.000 

100.000 

ppm

0 60 120 180 240 300 360 420 480 

Minutes

No Effect

Discomfort

Disabling

Some Lethality

Lethal

Chemical Toxicity - TSD Data

Tellurium Hexafluoride

AEGL-3

AEGL-2

AEGL

4 
TELLURIUM HEXAFLUORIDE Proposed: April 2009 

25

1 

2 

Category Plot Data 

Source Species Sex Exposure

# 

ppm Minutes Category Comments 

For Category: 0 = No effect, 1 = Discomfort, 2 = Disabling, SL = Some Lethality, 3 = Lethal 

NAC/AEGL-1 NR 10 AEGL 

NAC/AEGL-1 NR 30 AEGL 

NAC/AEGL-1 NR 60 AEGL 

NAC/AEGL-1 NR 240 AEGL 

NAC/AEGL-1 NR 480 AEGL 

NAC/AEGL-2 0.032 10 AEGL 

NAC/AEGL-2 0.022 30 AEGL 

NAC/AEGL-2 0.018 60 AEGL 

NAC/AEGL-2 0.011 240 AEGL 

NAC/AEGL-2 0.0057 480 AEGL 

NAC/AEGL-3 0.096 10 AEGL 

NAC/AEGL-3 0.067 30 AEGL 

NAC/AEGL-3 0.053 60 AEGL 

NAC/AEGL-3 0.033 240 AEGL 

NAC/AEGL-3 0.017 480 AEGL 

Kimmerle 1960 Rabbit M 1 1 240 2 Respiratory dysfunction, 

pulmonary edema 

Kimmerle 1960 Rabbit M 1 5 240 3 Death at 8 hours 

Kimmerle 1960 Rabbit M 1 10 240 3 Death at 140 min 

Kimmerle 1960 Rabbit M 1 25 240 3 Death at 80 min 

Kimmerle 1960 Rabbit M 1 50 240 3 Death at 60 min 

Kimmerle 1960 Rabbit M 1 100 240 3 Death at 15 min 

Kimmerle 1960 Rabbit M 1 1 60 1 Hyperpnea 

Kimmerle 1960 Rabbit M 1 5 60 2 Severe damage to respiratory 

organs 

Kimmerle 1960 Guinea pig M 1 1 240 2 Respiratory dysfunction, 

pulmonary edema 

Kimmerle 1960 Guinea pig M 1 5 240 3 Death at 8 hours 

Kimmerle 1960 Guinea pig M 1 10 240 3 Death at 140 min 

Kimmerle 1960 Guinea pig M 1 25 240 3 Death at 80 min 

Kimmerle 1960 Guinea pig M 1 50 240 3 Death at 60 min 

Kimmerle 1960 Guinea pig M 1 100 240 3 Death at 15 min 

Kimmerle 1960 Guinea pig M 1 1 60 1 Hyperpnea 

Kimmerle 1960 Guinea pig M 1 5 60 2 Severe damage to respiratory 

organs 

Kimmerle 1960 Rat M 1 1 240 2 Respiratory dysfunction, 

pulmonary edema 

Kimmerle 1960 Rat M 1 5 240 3 Death at 8 hours 

Kimmerle 1960 Rat M 1 10 240 3 Death at 140 min 

Kimmerle 1960 Rat M 1 25 240 3 Death at 80 min 

Kimmerle 1960 Rat M 1 50 240 3 Death at 60 min 

Kimmerle 1960 Rat M 1 100 240 3 Death at 15 min 

Kimmerle 1960 Rat M 1 1 60 1 Hyperpnea 
TELLURIUM HEXAFLUORIDE Proposed: April 2009 

26

Kimmerle 1960 Rat M 1 5 60 2 Severe damage to respiratory 

organs 

Kimmerle 1960 Mouse M 1 1 240 2 Respiratory dysfunction, 

pulmonary edema 

Kimmerle 1960 Mouse M 1 5 240 3 Death at 8 hours 

Kimmerle 1960 Mouse M 1 10 240 3 Death at 140 min 

Kimmerle 1960 Mouse M 1 25 240 3 Death at 80 min 

Kimmerle 1960 Mouse M 1 50 240 3 Death at 60 min 

Kimmerle 1960 Mouse M 1 100 240 3 Death at 15 min 

Kimmerle 1960 Mouse M 1 1 60 1 Hyperpnea 

Kimmerle 1960 Mouse M 1 5 60 3 Death between 24-36 hours 

NR = Not recommended due to insufficient data. Absence of an AEGL-1 value does not imply that exposure below the AEGL 

concentration is without adverse effects.

1 

2