Acute Exposure Guideline Levels for Selected Airborne Chemicals Volume 18 (2014) / Chapter Skim
Currently Skimming:
2 Carbonyl Fluoride
2 Carbonyl Fluoride
Pages 37-65
The Chapter Skim interface presents what we've algorithmically identified as the most significant single chunk of text within every page in the chapter.
Select key terms on the right to highlight them within pages of the chapter.
From page 37... ...
Both the document and the AEGL values were then reviewed by the National Research Council (NRC) Committee on Acute Exposure Guideline Levels.
|
From page 38... ...
Although the AEGL values represent threshold concentrations 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 idiosyncratic responses, could experience the effects described at concentrations below the corresponding AEGL. SUMMARY Carbonyl fluoride is a colorless and irritating gas, with a pungent odor.
|
From page 39... ...
However, carbonyl fluoride was generated via polytetrafluoroethylene pyrolysis in that study; therefore, exposure included other pyrolysis products. Exposure of rats to carbonyl fluoride at 310 ppm resulted in focal hemorrhage of the lungs and pulmonary edema, observed 24 h after exposure.
|
From page 40... ...
It is a thermal decomposition product of fluoropolymers, such as polytetrafluoroethylene and polyfluoroethylenepropylene, heated at temperatures above 500°C. Pyrolysis products are composed of a large number of compounds, can be of variable composition, and pose significant analytic challenges.
|
From page 41... ...
Rats Groups of two male ChR-CD rats were exposed to carbonyl fluoride by inhalation at nominal concentrations of 5 or 10 ppm and a group of six rats was exposed at 100 ppm for 4 h. Three rats exposed at 100 ppm died, and pathologic examination showed they had acute tracheobronchitis and pulmonary congestion.
|
From page 42... ...
(1968) , which identified carbonyl fluoride as a principal toxic component of the pyrolysis gases, as their rationale for using polytetrafluoroethylene pyrolysis to produce carbonyl fluoride.
|
From page 43... ...
b Exposed rats to polytetrafluoroethylene pyrolysis products (550ºC) and reported concentrations of measured fluoride.
|
From page 44... ...
Twenty male and 20 female rats (Greenacres Controlled Flora) were exposed to polytetrafluoroethylene pyrolysis products (temperature not reported)
|
From page 45... ...
Converting the LC50 for hydrogen fluoride to an equivalent concentration of carbonyl fluoride gives a predicted value of 680 ppm, nearly 50% greater than that observed. No data on the developmental toxicity, reproductive toxicity, genotoxicity, chronic toxicity, or carcinogenicity of carbonyl fluoride were found.
|
From page 46... ...
(1968a) reported deep lung focal hemorrhage and edema in rats exposed for 1 h to carbonyl fluoride produced from polytetrafluoroethylene pyrolysis.
|
From page 47... ...
6.2. Animal Data Relevant to AEGL-2 In a study of rats exposed to carbonyl fluoride at nominal concentrations of 2.5 or 5 ppm for 2 or 2.5 h, the no-effect level was 2.5 ppm for both durations.
|
From page 48... ...
However exposure to carbonyl fluoride was generated via polytetrafluoroethylene pyrolysis; therefore, exposure included other pyrolysis products. Exposure of rats to carbonyl fluoride at 310 ppm resulted in focal hemorrhage of the lungs and pulmonary edema, observed 24 h after exposure.
|
From page 49... ...
AEGL values for carbonyl fluoride are presented in Table 2-6. For comparison, Table 2-7 provides the AEGL values for phosgene and hydrogen fluoride, because those chemicals are also pyrolysis products of polytetrafluorethylene (see Sections 3.7, 4.1, and 4.2)
|
From page 50... ...
e (1 mg/m3) a TLV-TWA (threshold limit value – time-weighted average, American Conference of Governmental Industrial Hygienists)
|
From page 51... ...
The animals were also exposed to the particulate matter produced from polytetrafluoroethylene pyrolysis, which may have increased observed effects. Additional acute animal studies in other species and with a greater range of concentrations would be helpful in deriving AEGL values.
|
From page 52... ...
2001. Standing Operating Procedures for Developing Acute Exposure Guideline Levels for Hazardous Chemicals.
|
From page 53... ...
1968b. Biochemical changes associated with toxic exposures to polytetrafluoroethylene pyrolysis products.
|
From page 54... ...
1976. Acute Inhalation Toxicity Studies of Hydrogen Fluoride and Carbonyl Fluoride.
|
From page 55... ...
However, exposure to carbonyl fluoride was generated via polytetrafluoroethylene pyrolysis; therefore, exposure included other pyrolysis products. Exposure of rats to carbonyl fluoride at 310 ppm resulted in focal hemorrhage of the lungs and pulmonary edema, observed 24 h after exposure.
|
From page 56... ...
56 Acute Exposure Guideline Levels 1-h AEGL-3: C3 × 60 min = 33.74592 ppm-min C = 0.83 ppm 4-h AEGL-3: C × 240 min = 124.8 ppm-min C = 0.52 ppm 8-h AEGL-3: C × 480 min = 124.8 ppm-min C = 0.26 ppm
|
From page 57... ...
1976. Acute Inhalation Toxicity Studies of Hydrogen Fluoride and Carbonyl Fluoride.
|
From page 58... ...
. The 30-min AEGL-3 value was adopted for the 10-min value in accordance with the standing operating procedures for developing AEGL values (NRC 2001)
|
From page 59... ...
is the cumulative normal distribution function Dependent variable = COLUMN3 Independent variable = COLUMN1 Slope parameter is restricted as slope >= 1 Total number of observations = 8 Total number of records with missing values = 0 Maximum number of iterations = 250 Relative Function Convergence has been set to: 1e-008 Parameter Convergence has been set to: 1e-008 User has chosen the log transformed model Default Initial (and Specified) Parameter Values Background = 0 Intercept = -7.52665 Slope = 2.13336 Asymptotic Correlation Matrix of Parameter Estimates (*
|
From page 60... ...
P-value Full model -40.8638 8 Fitted model -44.0906 2 6.45349 6 0.3744 Reduced model -55.4518 1 29.1759 7 0.0001344 AIC: 92.1812 Goodness of Fit Dose Estimated Probability Expected Observed Size Scaled Residual 0.0000 0.0000 0.000 0 10 0.000 26.7000 0.3136 3.136 5 10 1.271 30.8000 0.4179 4.179 3 10 -0.756 32.7000 0.4639 4.639 3 10 -1.039 41.3000 0.6423 6.423 6 10 -0.279 44.7000 0.6981 6.981 8 10 0.702 47.2000 0.7340 7.340 9 10 1.188 47.6000 0.7394 7.394 6 10 -1.004 Chi-square = 6.26 d.f. = 6 P-value = 0.3951 Benchmark Dose Computation Specified effect = 0.05 Risk Type = Extra risk Confidence level = 0.95 BMD = 14.7319 BMDL = 5.21965 Probit Model with 0.95 Confidence Level Probit 1 BMD Lower Bound 0.8 Fraction Affected 0.6 0.4 0.2 0 BMDL BMD 0 10 20 30 40 50 dose 07:45 01/08 2008
|
From page 61... ...
is the cumulative normal distribution function Dependent variable = COLUMN3 Independent variable = COLUMN1 Slope parameter is restricted as slope >= 1 Total number of observations = 8 Total number of records with missing values = 0 Maximum number of iterations = 250 Relative Function Convergence has been set to: 1e-008 Parameter Convergence has been set to: 1e-008 User has chosen the log transformed model Default Initial (and Specified) Parameter Values Background = 0 Intercept = -7.52665 Slope = 2.13336 Asymptotic Correlation Matrix of Parameter Estimates (*
|
From page 62... ...
62 Acute Exposure Guideline Levels Goodness of Fit Dose Estimated Probability Expected Observed Size Scaled Residual 26.7000 0.3136 3.136 5 10 1.271 30.8000 0.4179 4.179 3 10 -0.756 32.7000 0.4639 4.639 3 10 -1.039 41.3000 0.6423 6.423 6 10 -0.279 44.7000 0.6981 6.981 8 10 0.702 47.2000 0.7340 7.340 9 10 1.188 47.6000 0.7394 7.394 6 10 -1.004 0.0000 0.0000 0.000 0 10 0.000 Chi-square = 6.2 d.f. = 6 P-value = 0.3951 Benchmark Dose Computation Specified effect = 0.01 Risk Type = Extra risk Confidence level = 0.95 BMD = 10.3855 BMDL = 2.64042 Probit Model with 0.95 Confidence Level Probit 1 BMD Lower Bound 0.8 Fraction Affected 0.6 0.4 0.2 0 BMDL BMD 0 10 20 30 40 50 dose 11:24 11/15 2007
|
From page 63... ...
Carbonyl Fluoride 63 APPENDIX E CATEGORY PLOT FOR CARBONYL FLUORIDE Chemical Toxicity Carbonyl Fluoride 1000.0 Human - No Effect Human - Discomfort 100.0 Human - Disabling Animal - No Effect 10.0 ppm Animal - Discomfort 1.0 AEGL-3 Animal - Disabling Animal - Some Lethality AEGL-2 0.1 Animal - Lethal AEGL 0.0 0 60 120 180 240 300 360 420 480 Minutes FIGURE E-1 Category plot of toxicity data and AEGL values for carbonyl fluoride.
|
From page 64... ...
Category Comments AEGL-2 0.35 10 AEGL AEGL-2 0.35 30 AEGL AEGL-2 0.28 60 AEGL AEGL-2 0.17 240 AEGL AEGL-2 0.087 480 AEGL AEGL-3 1 10 AEGL AEGL-3 1 30 AEGL AEGL-3 0.83 60 AEGL AEGL-3 0.52 240 AEGL AEGL-3 0.26 480 AEGL DuPont 1956 Rat M 1 2.5 120 0 No effect DuPont 1956 Rat M 1 2.5 150 0 No effect DuPont 1956 Rat M 1 5 120 1 Slight dyspnea; cyanosis DuPont 1956 Rat M 1 5 150 1 Slight dyspnea; cyanosis DuPont 1959 Rat M 1 5 240 1 Rapid, shallow respiration DuPont 1959 Rat M 1 10 240 1 Rapid, shallow respiration DuPont 1959 Rat M 1 100 240 SL Pulmonary congestion Scheel et al. 1968a Rat B 1 360 60 SL 50% mortality Scheel et al.
|
From page 65... ...
Scheel et al. 1968a Rat B 1 90 240 SL 50% mortality DuPont 1976 Rat M 1 26.7 240 SL 50% mortality DuPont 1976 Rat M 1 30.8 240 SL 30% mortality DuPont 1976 Rat M 1 32.7 240 SL 30% mortality DuPont 1976 Rat M 1 41.3 240 SL 60% mortality DuPont 1976 Rat M 1 44.7 240 SL 80% mortality DuPont 1976 Rat M 1 47.2 240 SL 90% mortality DuPont 1976 Rat M 1 47.6 240 SL 60% mortality For category: 0 = no effect, 1 = discomfort, 2 = disabling, SL = some lethality, 3 = lethality.
|
Key Terms
This material may be derived from roughly machine-read images, and so is provided only to facilitate research.
More
information on Chapter Skim is available.