## ACUTE EXPOSURE GUIDELINE LEVELS (AEGLs) FOR TELLURIUM HEXAFLUORIDE CAS Reg. No. 7783-80-4

PROPOSEDTELLURIUM HEXAFLUORIDE Proposed: April 2009

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## ACUTE EXPOSURE GUIDELINE LEVELS (AEGLs) FOR TELLURIUM HEXAFLUORIDE (CAS Reg. No. 7783-80-4)

PROPOSED

Oak Ridge National Laboratory, managed by UT-Ba ttelle, LLC, for the U.S. Dept. of Energy under contract DE-AC05-00OR22725TELLURIUM 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 Adviso ry Committee Act (FACA) P. L. 92-463 of 1972, the National Advisory Committee for Acut e Exposure Guideline Levels for Hazardous Substances (NAC/AEGL Committee) has been established to identify, review and interpret relevant toxicologic and other sc ientific data and develop AEGLs for high priority, acutely toxic chemicals.

AEGLs represent threshold exposure limits for the general public a nd are applicable to emergency exposure periods ranging from 10 minutes to 8 hours. Three levels

C AEGL-1, AEGL-2 and AEGL-3

Care developed for each of five e xposure periods (10 and 30 minutes, 1 hour, 4 hours, and 8 hours) and are distinguished by va rying degrees of severity of toxic effects. The three AEGLs are defined as follows:

AEGL-1 is the airborne concentration (expres sed 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 indi viduals, could experience notab le discomfort, irritation, or certain asymptomatic, non-sensory effects. Ho wever, the effects are not disabling and are transient and reversible upon cessation of exposure.

AEGL-2 is the airborne concentration (expresse d as ppm or mg/m3) of a substance above which it is predicted that th e general population, including su sceptible individuals, could experience irreversible or other serious, long-lasting adverse hea lth effects or an impaired ability to escape.

AEGL-3 is the airborne concentration (expres sed as ppm or mg/m3) of a substance above which it is predicted that th e general population, including su sceptible individuals, could experience life-threatening health effects or death.

Airborne concentrations below the AEGL-1 re present exposure levels that could produce mild and progressively increas ing but transient and nondisab ling odor, taste, and sensory irritation or certain asymptomatic , non-sensory effects. With incr easing airborne concentrations above each AEGL, there is a progressive increase in the likelihood of occu rrence 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 asthm a, and thos e with other illnesses, it is recognized that individuals, subject to unique or idiosyncratic responses, could experience the effects described at concentrations belo w the corresponding AEGLTELLURIUM 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.

............................................................................................................................... .7 INTRODUCTION 2. ...............................................................................................................7 HUMAN TOXICITY DATA 2.1.

............................................................................................................................... .7 Acute Lethality 2.2. ...........................................................................................................................7 Nonlethal Toxicity 2.2.1. ............................................................................................7 Odor Threshold/Odor Awareness 2.2.2. ............................................................................................................................7 Case Reports 2.3. ...................................................................................................................................8 Neurotoxicity 2.4. ............................................................................................8 Developmental/Reproductive Toxicity 2.5. .....................................................................................................................................8 Genotoxicity 2.6.

............................................................................................................................... .8 Carcinogenicity 2.7. ..........................................................................................................................................8 Summary 3. ..............................................................................................................8 ANIMAL TOXICITY DATA 3.1.

............................................................................................................................... .8 Acute Lethality 3.2. ...........................................................................................................................9 Nonlethal Toxicity 3.3. ............................................................................................9 Developmental/Reproductive Toxicity 3.4.

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

............................................................................................................................... .........10 Summary 4. ........................................................................................................10 SPECIAL CONSIDERATIONS 4.1. ..........................................................................................................10 Metabolism and Disposition 4.2. ..................................................................................................................10 Mechanism of Toxicity 4.3. ....................................................................................................10 Structure Activity Relationships 4.4. ...........................................................................................................11 Other Relevant Information 4.4.1. ................................................................................................................11 Species Variability 4.4.2. ........................................................................................................11 Susceptible Populations 4.4.3. ...................................................................12 Concentration-Exposure Duration Relationship 4.4.4. ..................................................................................................12 Concurrent Exposure Issues 5. ....................................................................................................12 DATA ANALYSIS FOR AEGL-1 5.1. ............................................................................12 Summary of Human Data Relevant to AEGL-1 5.2. ............................................................................12 Summary of Animal Data Relevant to AEGL-1 5.3. ...................................................................................................................12 Derivation of AEGL-1 6. ....................................................................................................12 DATA ANALYSIS FOR AEGL-2 6.1. ............................................................................12 Summary of Human Data Relevant to AEGL-2 6.2. ............................................................................12 Summary of Animal Data Relevant to AEGL-2 6.3. ...................................................................................................................13 Derivation of AEGL-2 7. ....................................................................................................13 DATA ANALYSIS FOR AEGL-3 7.1. ............................................................................13 Summary of Human Data Relevant to AEGL-3 7.2. ............................................................................13 Summary of Animal Data Relevant to AEGL-3 7.3. ...................................................................................................................13 Derivation of AEGL-3 8. ...................................................................................................................14 SUMMARY OF AEGLS 8.1. ..........................................................................................14 AEGL Values and Toxicity Endpoints 8.2. ........................................................................14 Comparison with Other Standards and Guidelines 8.3. ........................................................................................................15 Data Adequacy and Research 9.

............................................................................................................................... ....16 REFERENCES APPENDIX A: DERIVATION OF AEGL VALUES ...............................................................................18 APPENDIX B: DERIVATION SUMMARY FOR TELLURIUM HEXAFLUORIDE AEGLS .............21 APPENDIX C: CATEGORY PLOT FOR TELLURIUM HEXAFLUORIDE .........................................24TELLURIUM HEXAFLUORIDE Proposed: April 2009

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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 ................................................15TELLURIUM 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 refi ning. It is a colorless gas with a repulsive odor. It decomposes slowly in water to form hyd rogen 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 in sufficient 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 (N RC 2001). The steep concentration response is evidenced by the fact that rabbits, guinea pi gs, 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 hexa fluoride is highly irritating and corrosive, and much of the toxicity is likely caused by a direct chemical effect on the tissu e; 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 effect s of tellurium and the sparse database. Thus, the total adjustment is 30. The concentration- exposure time relationshi p for many irritant and systemically-acting vapors a nd gases may be described by C n 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 deri ved chemical-specific sc aling exponent, temporal scaling was performed using n=3 when extrapol ating to shorter time points (10-, 30-, and 60- min) and n = 1 when extrapolating to longer time points (8 hr) using the C n x t = k equation.

The calculated values are lis ted 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)

AEGL

B 1a (Nondisabling) NR NR NR NR NR Not recommended due to insufficient data AEGL

B 2 (Disabling) 0.032 ppm (0.32 mg/m 3 ) 0.022 ppm (0.22 mg/m 3 ) 0.018 ppm (0.18 mg/m 3 ) 0.011 ppm (0.11 mg/m 3 ) 0.0057 ppm (0.056 mg/m 3 ) One-third of the AEGL3 values (NRC 2001)

AEGL

B 3 (Lethal) 0.096 ppm (0.95 mg/m 3 ) 0.067 ppm (0.66 mg/m 3 ) 0.053 ppm (0.52 mg/m 3 ) 0.033 ppm (0.33 mg/m 3 ) 0.017 ppm (0.17 mg/m 3 ) 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 t he AEGL2 concentration is without adverse effects. 37 38 39 40TELLURIUM HEXAFLUORIDE Proposed: April 2009

7 1 2 3 4 5 6 7 8 1. INTRODUCTION

Tellurium hexafluoride is a colorless gas create d by the direct fluorinat ion of tellurium metal (HSDB 2005). It hydrolyzes slowly in water to hydrogen fluoride a nd 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 phys ical properties are listed in Table 2.

TABLE 2. Chemical a nd Physical Properties

Parameter Value References

Synonyms Tellurium fluoride (TeF6), (OC-6-11); Tellurium fluoride (TeF6) HSDB 2005

Chemical formula Te F 6 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/m 3 1 mg/m 3 = 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 repu lsive 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 wh en 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 ur ine. 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 develope d bluish-black patches between the fingers and on the neck and face which took several weeks to fade. The s econd man experienced garlic odor of the breath and bluish-black patches on the skin. Liver functi on tests, renal function tests, urinalysis, chest radiographs, blood electrolytes, a nd blood indices were all normal. The men were not treated and both completely recovered with the garlic odor and blue-bl ack patches taking several weeks to clear. The blue-black patches were thought to be the re sult 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 cau sed metallic taste in mouth, tiredness, sour garlic odor in the breath, sweat, and urine, a nd bluish-black patches on the skin. Tellurium hexafluoride is a respiratory irritant and humans may experience breathing difficulties following inhalational exposure (NIO SH 1978; OSHA 1996).

3. ANIMAL TOXICITY DATA 3.1. Acute Lethality

Kimmerle (1960) exposed one rabbit, one guine a 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 hexafl uoride 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 hexafl uoride 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 guine a pig, two male white rats, and four male white mice per group to 1 or 5 ppm tellurium he xafluoride for 1 or 4 hours as described in section 3.1. Significantly increa sed respiratory frequency (hyp erpnea) 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. Expos ure 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 anim als. In the rabbit, liv er 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 teste d. Clinical signs (respiratory distress) and post-mortem findings (pulmonary edema) were cons istent with severe irritation in all animals except those exposed to 1 ppm for 1 hour who exhibited hyperpnea. No data on developmental/ reproductive toxi city, genotoxicity, or chronic toxicity/carcinogenicity were located.

4. SPECIAL CONSIDERATION S 4.1. Metabolism and Disposition

Little information was located concerning the metabolism and disposition of tellurium hexafluoride. However, tellurium hexafluoride ma y be hydrolyzed in the moist respiratory tract to hydrogen fluoride and the telluri um ion or telluric acid (HSDB 2005). Tellurium is distributed through the body. In the liver, hepatic metabolism cr eates 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 th at tellurium hexafluoride slowly hydrolyzes into hydrogen fluoride and tellurium ion or telluric aci d. Kimmerle (1960) has shown that the toxic effects of inhaled tellurium hexafluoride are c onsistent with severe irritation/corrosivity. Hydrogen fluoride is a severe irrita nt 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 hydr ogen fluoride to the lungs produces pulmonary hemorrhage and edem a and may result in death (NRC 2004). The mechanism of toxicity of tellurium is unknown. It has been shown that te llurium inhibits squalene epoxi dase 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 seleni um 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 seleniumTELLURIUM 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, guin ea pigs, rats, and mice exposed to 10 ppm selenium hexafluoride for 4 hours died while thos e exposed to 5 or 1 ppm selenium hexafluoride survived the exposure. Animals exposed to 5 ppm selenium hexafluorid e exhibited difficulty breathing and pulmonary edema, which resolved during the follow-up period. No effects were observed in animals exposed to 1 ppm selenium he xafluoride. All rabbits, guinea pigs, rats, and mice exposed to 5 ppm tellurium hexafluoride fo r 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 hydroge n fluoride on a molar basis. However, the limited data set suggests that tell urium hexafluoride is much more than six times as toxic as hydrogen fluoride.

The of one-hour LC 50 values for hydrogen fluoride fo r the mouse ranges from 342 to 501 ppm (NRC 2004). If the acute i nhalation toxicity of tellurium hexafluoride was due only to the hydrogen fluoride hydrolysis product , then approximate 1-hour LC 50 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 (Kimme rle, 1960). The increased relative toxicity of tellurium hexafluoride may be due to the tell urium moiety and the sl ow 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 esp ecially sensitive to tellurium hexafluoride toxicity. However, the steep concentration-response curve implies limited intraspecies variability. Rabbits, guinea pigs, rats, and mi ce 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 func tion might respond to exposure to tellurium hexafluoride with exacerbation of symptoms due to its irritant propert ies (NIOSH 1978). No information on the relative susceptibility of i ndividuals with impaired pulmonary function and normal individuals to telluri um 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 C n 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 wh en extrapolating to sh orter time points and n = 1 when extrapolating to l onger time points using the C n 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 developm ent of AEGL-1 values were identified.

5.2. Summary of Animal Data Relevant to AEGL-1

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

5.3. Derivation of AEGL-1

AEGL-1 values are not recommended due to in sufficient 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 t he 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 developm ent of AEGL-2 values were identified.

6.2. Summary of Animal Data Relevant to AEGL-2

Kimmerle (1960) exposed one rabbit, one guine a pig, two male white rats, and four male white mice per group to 1 or 5 ppm tellurium he xafluoride 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 AE GL-2 severity effects. Animals experienced hyperpnea from exposure to 1 ppm tellurium he xafluoride for 1 hour. In the absence of empirical data, and in accord with AEGL deri vation 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 pi gs, rats, and mice exposed to 5, 10, 25, 50, or 100 ppm tellurium hexafluoride for 4 hours all di ed. Animals exposed to 1 ppm for 4 hours survived. AEGL-2 values are presented in Ta ble 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/m 3 ) 0.022 ppm (0.22 mg/m 3 ) 0.018 ppm (0.18 mg/m 3 ) 0.011 ppm (0.11 mg/m 3 ) 0.0057 ppm (0.056 mg/m 3 ) 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 developmen t 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 (Ki mmerle 1960). All mice exposed to 5 ppm for 1 hour died; the remaining animals recovered very slowly from se vere damage to the respiratory organs. The same animals exposed to 1 ppm for 4 hours su rvived but experienced pulmonary edema and respiratory dysfunction. Animals ex posed to 1 ppm for 1 hr experien ced hyperpnea but survived.

7.3. Derivation of AEGL-3

The highest concentration causing no mortality in the rabbit, guinea pi g, 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 te llurium hexafluoride is highly irritating and corrosive, and much of the toxicity is likely cause d by a direct chemical effect on the tissue; this type of portal-of-entry effect is not expected to vary grea tly among individuals. The steep concentration-response curve implies limited intr a-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 telluri um and the sparse database. Thus, the total adjustment is 30. The concentrat ion-exposure time relationship for many irritant and systemically-acting vapors a nd gases may be described by C n 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 deri ved chemical-specific sc aling exponent, temporal scaling was performed using n=3 when extrapolati ng to shorter time point s (10-, 30-, and 6-min)TELLURIUM HEXAFLUORIDE Proposed: April 2009

14 1 2 3 4 and n = 1 (8 hr) when extrapolati ng to longer time points using the C n x t = k equation. AEGL-3 values are presented in Table 6, and ca lculations 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/m 3 ) 0.067 ppm (0.66 mg/m 3 ) 0.053 ppm (0.52 mg/m 3 ) 0.033 ppm (0.33 mg/m 3 ) 0.017 ppm (0.17 mg/m 3 ) 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-mi nute value was calculated from the 4-hour time point and this approach is supported by the 1 hou r 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 valu e and applying the total adjustme nt (uncertainty and modifying factor) of 30 yields a value of 2 ppm-min, s uggesting 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 he xafluoride for 4 hours all died. All mice exposed to 5 ppm for 1 hour died. All animal s exposed to 1 ppm for 1 or 4 hours survived. AEGL-3 values were based on the highest concen tration 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/m 3 ) 0.022 ppm (0.22 mg/m 3 ) 0.018 ppm (0.18 mg/m 3 ) 0.011 ppm (0.11 mg/m 3 ) 0.0057 ppm (0.056 mg/m 3 ) AEGL-3 (Lethal) 0.096 ppm (0.95 mg/m 3 ) 0.067 ppm (0.66 mg/m 3 ) 0.053 ppm (0.52 mg/m 3 ) 0.033 ppm (0.33 mg/m 3 ) 0.017 ppm (0.17 mg/m 3 )

NR =AEGL-1 values are not recommended due to insufficient data. Absence of an AEGL-1 value does not imply that exposure below t he AEGL2 concentration is without adverse effects. 27 28 29 30 31 32 33 34 35 36 37 8.2. Comparison with Other St andards and Guidelines

AEGL values for tellurium hexafluoride are compared to other guidelines and standards for this compound in Table 8. The time-weighted aver age exposure concentrat ion 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 th at tellurium hexafluorid e is approximately 2.5 times as acutely toxic as ozone and to protec t against respiratory effects (ACGIH 1991). The IDLH (NIOSH 1996) was based on acute inhala tion toxicity data from Kimmerle (1960).TELLURIUM HEXAFLUORIDE Proposed: April 2009

15 1 2 TABLE 8. Extant Standards and Gu idelines 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/m 3 ) 0.022 ppm (0.22 mg/m 3 ) 0.018 ppm (0.18 mg/m 3 ) 0.011 ppm (0.11 mg/m 3 ) 0.0057 ppm (0.056 mg/m 3 )

AEGL-3 0.096 ppm (0.95 mg/m 3 ) 0.067 ppm (0.66 mg/m 3 ) 0.053 ppm (0.52 mg/m 3 ) 0.033 ppm (0.33 mg/m 3 ) 0.017 ppm (0.17 mg/m 3 ) 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 t he 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 Sa fety Administration, Permi ssible 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 Occupa tional 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 In stitute of Occupational Safety and Health, Recommended Exposure Limits - Time Weighted Average) (NIOSH 2005) is define d an alogous to the ACGIH-TLV-TWA.

d ACGIH TLV-TWA (American Conference of Governmental Industrial Hygienists, Th reshold Limit Value - Time Weighted Average) (ACGIH 2008) is the time-weighted average con centr ation for a normal 8-hour workday and a 40-hour work week, to which nearly all workers may be repeated ly 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 Employ ment], 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 anim al data are limited. A single study that addressed acute toxicity of tellu rium hexafluoride in a limited nu mber 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 st udies 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 I ndustrial Hygienists). 1991. Documentation of the Threshold Limit Values and Biologica l Exposure Indices: Tellurium Hexafluoride. Sixth ed., ACGIH, Cincinnati, OH.

ACGIH (American Conference of Governmental I ndustrial Hygienists). 2008. Threshold limit values (TLVs) for chemical and physical agen ts and biological expos ure 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 Toxico logy: The Basic Science of Poisons, 6 th Ed., C.D. Klaassen, ed. New York: McGraw-Hill. p.554.

Blackadder, E.S. and W.G. Manderson. 1975. Occupa tional absorption of tellurium: a report of two cases. Br. J. Ind. Med. 32: 59-61.

HSDB (Hazardous Substances Data Bank). 2005. Tellu rium Hexafluoride. [Online] Available. http://toxnet.nlm.nih.gov/ [02/ 197/2008]. TOXNET, Toxicology Data Network. US. Natl. Library of Medicine.

IPCS (International Programm e on Chemical Safety). 1998. Te llurium 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 inha lation toxicity of sulfur-, selenium-, and tellurium –hexafluoride]. Arch. Toxikol. 18: 140-144.

NIOSH (National Institute for Occupational Sa fety and Health). 1978. Occupational Health Guideline for Tellurium Hexafluoride. [Onlin e] Available. http:// www.cdc.gov/niosh/pdfs/ 0588.pdf [02/04/2009].

NIOSH (National Institute for Occupational Sa fety and Health). 1996. Documentation for Immediately Dangerous to Life and Health C oncentrations (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. Acut e 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. Standi ng Operating Procedures for Developing Acute Exposure Guideline Levels for Hazardous Ch emicals. 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, 13 th ED. Whitehouse Station, NJ: Merck and Co. 3984.

OSHA (Occupational Safety and Health Administra tion). 1996. Occupational Safety and Health Guideline for Tellurium Hexafluoride. [On line] Available. h ttp://www.osha.gov/SLTC/ healthguidelines/telluriumhexafl uoride/recognition.html [02/04/2009].

OSHA (Occupational Safety and Health Administ ration). 2005. Code of Federal Regulations, CFR 29, Part 1910, Table Z-1.

SDU Uitgevers 2000. MAC Ministry of Social Affairs and Em ployment. Nationale MAC (Maximum Allowable Concentration) Li st, 2000. The Hague, The Netherlands.

ten Berge, W.F., A. Zwart, and L.M. Appelman . 1986. Concentration-time mortality response relationship of irritant and sy stemically acting vapours and gase s. 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 th e AEGL-2 concentrati on 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 NRTELLURIUM 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 empi rical data, and in accord with AEGL derivation guidelines for chemicals with stee p dose-response curves, the AEGL-2 values for tellurium hexafluoride were set at one-third of the AEGL-3 values (NRC 2001). Rabbits, guinea pi gs, 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. Al l 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 ppmTELLURIUM 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 causi ng 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 caus ed by a direct chemical effect on the tissues; this type of porta l-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 C 3 x t = k (10- min, 30-min, 60-min) (0.0333333 ppm) 3 x 240 min = 0.0088888622 ppm 3 -min

C 1 x t = k (4-hr, 8-hr) 0.0333333 ppm 1 x 240 min = 7.999992 ppm-min

10-minute AEGL-3 C 3 x 10 minutes = 0.0088888622 ppm 3 ·min C = 0.096 ppm

30-minute AEGL-3: C 3 x 30 minutes = 0.0088888622 ppm 3 ·min C = 0.067 ppm

1-hour AEGL-3: C 3 x 30 minutes = 0.0088888622 ppm 3 ·min C = 0.053 ppm

4-hour AEGL-3: C 1 x 240 minutes = 7.999992 ppm·min C = 0.033 ppm

8-hour AEGL-3: C 1 x 480 minutes = 7.999992 ppm·min C = 0.017 ppmTELLURIUM HEXAFLUORIDE Proposed: April 2009

21 1 2 3 4 5 6

7 APPENDIX B: Derivation Summary for T ellurium 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 wit hout adverse effects. 8 9TELLURIUM 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 pi g (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

3TELLURIUM 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 pi g (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 pi g, rabbit, rat, and mouse are similarly sensitive to the acute effects of tellurium hexafluoride Intraspecies: 3, tellurium hexafluoride is highly irrita ting and corrosive, and much of the toxicity is likely caused by a direct chemical effect on the tissues; this ty pe of portal-of-entry effect is not expected to vary greatly among individuals. Modifying Factor: 10, to account for potential effects of te llurium and the sparse database Animal to Human Dosimetric Adjustment: none Time Scaling: c n 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 spar se data base consisting of one lethality study in laboratory animals.

5TELLURIUM HEXAFLUORIDE Proposed: April 2009

24 1 2 3 APPE NDIX C: Category Plot for Tellurium Hexafluoride

0.001 0.010 0.100 1.000 10.000 100.000ppm

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

4TELLURIUM 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

N AC/AEGL-1 NR 10 AEGL

N AC/AEGL-1 NR 30 AEGL

N AC/AEGL-1 NR 60 AEGL

N AC/AEGL-1 NR 240 AEGL

N AC/AEGL-1 NR 480 AEGL

N AC/AEGL-2 0.032 10 AEGL

N AC/AEGL-2 0.022 30 AEGL

N AC/AEGL-2 0.018 60 AEGL

N AC/AEGL-2 0.011 240 AEGL

N AC/AEGL-2 0.0057 480 AEGL

N AC/AEGL-3 0.096 10 AEGL

N AC/AEGL-3 0.067 30 AEGL

N AC/AEGL-3 0.053 60 AEGL

N AC/AEGL-3 0.033 240 AEGL

N AC/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 HyperpneaTELLURIUM 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 wit hout adverse effects. 1 2