U.S. Environmental Protection Agency Hazard Characterization Document September, 2014 SCREENING-LEVEL HAZARD CHARACTERIZATION SPONSORED CHEMICAL Vinyl Fluoride (CASRN 75-02-5) SUPPORTING CHEMICAL Vinyl Chloride (CASRN 75-01-4) The High Production Volume (HPV) Challenge Program1 was conceived as a voluntary initiative aimed at developing and making publicly available screening-level health and environmental effects information on chemicals manufactured in or imported into the United States in quantities greater than one million pounds per year. In the Challenge Program, producers and importers of HPV chemicals voluntarily sponsored chemicals; sponsorship entailed the identification and initial assessment of the adequacy of existing toxicity data/information, conducting new testing if adequate data did not exist, and making both new and existing data and information available to the public. Each complete data submission contains data on 18 internationally agreed to "SIDS" (Screening Information Data Set1'2) endpoints that are screening-level indicators of potential hazards (toxicity) for humans or the environment. The Environmental Protection Agency's Office of Pollution Prevention and Toxics (OPPT) is evaluating the data submitted in the HPV Challenge Program on approximately 1400 sponsored chemicals by developing hazard characterizations (HCs). These HCs consist of an evaluation of the quality and completeness of the data set provided in the Challenge Program submissions. They are not intended to be definitive statements regarding the possibility of unreasonable risk of injury to health or the environment. The evaluation is performed according to established EPA guidance2'3 and is based primarily on hazard data provided by sponsors; however, in preparing the hazard characterization, EPA considered its own comments and public comments on the original submission as well as the sponsor's responses to comments and revisions made to the submission. In order to determine whether any new hazard information was developed since the time of the HPV submission, a search of the following databases was made from one year prior to the date of the HPV Challenge submission to the present: (ChemID to locate available data sources including Medline/PubMed, Toxline, HSDB, IRIS, NTP, AT SDR, IARC, EXTOXNET, EPA SRS, etc.), STN/CAS online databases (Registry file for locators, ChemAbs for toxicology data, RTECS, Merck, etc.), Science Direct and ECHA4. OPPT's focus on these specific sources is based on their being of high quality, highly relevant to hazard characterization, and publicly available. OPPT does not develop HCs for those HPV chemicals which have already been assessed internationally through the HPV program of the Organization for Economic Cooperation and 1 U.S. EPA. High Production Volume (HPV) Challenge Program; http://www.epa.gov/chemrtk/index.htm. 2 U.S. EPA. HPV Challenge Program - Information Sources; http://www.epa.gov/chemrtk/pubs/general/guidocs.htm. 3 U.S. EPA. Risk Assessment Guidelines; http://cfpub.epa.gov/ncea/raf/rafguid.cfm. 4 European Chemicals Agency, http://echa.europa.eu. ------- U.S. Environmental Protection Agency Hazard Characterization Document September, 2014 Development (OECD) and for which Screening Initial Data Set (SIDS) Initial Assessment Reports (SIAR) and SIDS Initial Assessment Profiles (SIAP) are available. These documents are presented in an international forum that involves review and endorsement by governmental authorities around the world. OPPT is an active participant in these meetings and accepts these documents as reliable screening-level hazard assessments. These hazard characterizations are technical documents intended to inform subsequent decisions and actions by OPPT. Accordingly, the documents are not written with the goal of informing the general public. However, they do provide a vehicle for public access to a concise assessment of the raw technical data on HPV chemicals and provide information previously not readily available to the public. 2 ------- U.S. Environmental Protection Agency Hazard Characterization Document September, 2014 Chemical Abstract Service Registry Number (CASRN) Sponsored Chemical 75-02-5 Supporting Chemical 75-01-4 Chemical Abstract Index Name Sponsored Chemical Ethene, fluoro- Supporting Chemical Ethene, chloro- Sponsored Chemical Structural Formula SMILES: FCC Supporting Chemical -^^ci SMILES: C=CC1 Summary Vinyl fluoride is a clear, colorless gas with high vapor pressure and high water solubility. It is expected to have high mobility in soil. Volatilization of vinyl fluoride is high. The rate of hydrolysis is expected to be negligible. The rate of atmospheric photooxidation is slow. Vinyl fluoride is not readily biodegradable. Vinyl fluoride is expected to have moderate persistence (P2) and low bioaccumulation potential (Bl). Acute inhalation toxicity of vinyl fluoride to mice is low. In 90-day repeated inhalation toxicity studies in rats and mice, vinyl fluoride showed concentration-related increases in cell proliferation in livers of all treated mice and rats, and in olfactory mucosa of mice at > 200 ppm; the NOAEC was not established. No specific reproductive toxicity studies are available with vinyl fluoride; however, no effects on the reproductive organs were seen in the 90-day inhalation study in rats. In an inhalation two-generation reproductive toxicity study in rats with the supporting chemical, vinyl chloride, no effects on reproductive parameters were observed at any concentration; the NOAEC for reproductive toxicity is 1100 ppm (highest concentration tested). No developmental toxicity studies are available for vinyl fluoride. In 3 ------- U.S. Environmental Protection Agency Hazard Characterization Document September, 2014 prenatal inhalation developmental toxicity studies in rats and mice with the supporting chemical, vinyl chloride, the following treatment-related developmental effects were observed at 500 ppm and above: increased fetal resorption, decreased corpora lutea/dam in rats, decreased live fetuses/litter in mice, increased fetal loss or pregnancy wastage in rats, decreased fetal body weight in rats and mice, increased fetal crown-rump length in rats, increased incidences of rib spurs and dilated ureters in rats, increased incidences of unfused or delayed ossification of sternebrae in mice and an increased incidence of delayed ossification of the skull in mice. The NOAEC for maternal and developmental toxicity was not established in rats; the NOAEC for maternal and developmental toxicity in mice is 50 ppm and 500 ppm, respectively. In rabbits exposed to the supporting chemical vinyl chloride, decreased feed consumption, number of corpora lutea per dam, number of implantations per dam and number of live fetuses per litter and an increase in the incidence of delayed ossification were seen at 500 ppm but not at 2500 ppm; the NOAEC for maternal and developmental toxicity was 2500 ppm (highest concentration tested). Vinyl fluoride is mutagenic in bacteria and mammalian cells in vitro and it induced chromosomal aberrations in vitro and in vivo. Vinyl fluoride showed no effects on spermatocytes or germ cells in the unscheduled DNA synthesis and dominant lethal assays in rats, respectively. Vinyl fluoride increased the incidence of tumors in rats and mice. The International Agency for Research on Cancer (IARC) states that "for practical purposes, vinyl fluoride should be considered to act similarly to the human carcinogen vinyl chloride". The 96-h LCso value for fish exposed to vinyl fluoride is 210 mg/L, based on the supporting chemical (vinyl chloride). Adequate aquatic invertebrate and algal toxicity test data are not available for vinyl fluoride or vinyl chloride. Data gaps for the acute toxicity to aquatic invertebrates and toxicity to aquatic plants endpoints were identified under the HPV Challenge Program. 4 ------- U.S. Environmental Protection Agency Hazard Characterization Document September, 2014 The sponsor, E.I. Du Pont de Nemours & Company, Inc., submitted a Test Plan and Robust Summaries to EPA for vinyl fluoride (CASRN 75-02-5; CA Index name: ethene, fluoro-) on December 18, 2003. EPA posted the submission on the ChemRTK HPV Challenge website on February 18, 2004 (http://www.epa.gov/oppt/chemrtk/pubs/summaries/fluretln/cl4972tc.htm). EPA comments on the original submission were posted to the website on December 22, 2004. Public comments were also received and posted to the website. The sponsor submitted updated/revised documents on April 14, 2005, which were posted to the ChemRTK website on January 31, 2007. Justification for Supporting Chemical Studies on vinyl chloride (CASRN 75-01-4), a proposed supporting chemical of vinyl fluoride, were used to address the aquatic toxicity (e.g., fish, aquatic invertebrates and aquatic plants) and developmental toxicity endpoints. The use of data on vinyl chloride for aquatic toxicity endpoints was supported by ECOSAR data, which indicated that vinyl chloride was estimated to be slightly more toxic, and thus a conservative supporting chemical. The biotransformation pathway for vinyl fluoride is thought to be similar to that of vinyl chloride, that is, cytochrome P-450 mediated oxidation to the haloethylene oxide (fluoroethylene oxide), followed by rearrangement to the haloacetaldehyde (2-fluoroacetaldehyde), which is oxidized to fluoroacetic acid (10th RoC, 2002). Based on similar metabolic pathways and comparable toxicity data (e.g. liver toxicity) the use of data for vinyl chloride to address human health endpoints for vinyl fluoride is considered appropriate for this hazard characterization. Vinyl chloride has been assessed in several programs: OECD HPV program (US SIAM 13: http://www.chem.unep.ch/irptc/sids/OECDSIDS/VINYLCIIL.pdf). EPA IRIS (http://www.epa.gov/iris/subst/1001 .htm) , AT SDR (2006: http://www.atsdr.cdc.gov/ToxProfiles/tp20.pdf) and AEGL (http://www.epa.gov/oppt/aegl/pubs/results74.htm). 1. Chemical Identity 1.1 Identification and Purity Vinyl fluoride is a clear, colorless gas with high vapor pressure and high water solubility. 1.2 Physical-Chemical Properties The physical-chemical properties of vinyl fluoride are summarized in Table 1. 5 ------- U.S. Environmental Protection Agency Hazard Characterization Document September, 2014 Table 1. Physical-Chemical Properties of Vinyl fluoride1 Property Value CASRN 75-02-5 Molecular Weight 46.04 Physical State Clear, colorless, liquefied gas Melting Point -160.5°C (measured) Boiling Point -72°C (measured) Vapor Pressure 1.98x 104 mm Hg at 25°C (extrapolated) 43. 65 mm Hg at -111.9°C (measured)4 Dissociation Constant (pKa) Not applicable Henry's Law Constant 0.12 atm-m3/mole (estimated)2 Water Solubility 9,400 mg/L at 3.4 MPa and 80°C (measured)1'3; 15,400 mg/L 6.9 Mpa and 80°C (measured)1'3 Log Kow 1.19 (estimated)2 'DuPont Corporation. 2005. Revisions to Test Plan and Robust Summary for Fluoroethylene. Available online at http://www.epa. gov/chemrtk/pubs/summaries/fluretln/c 14972tc.htm as of April 16, 2012. 2U.S. EPA. 2012. Estimation Programs Interface Suite™ for Microsoft® Windows, v4.10. U.S. Environmental Protection Agency, Washington, DC, USA. Available online at http://www.epa.gov/opptintr/exposure/pubs/episuitedl.htm as of April 16, 2012. 3Although the water solubility was measured at extremely high pressures and elevated temperature, it is unlikely that any reasonable measurement can be obtained at standard temperature and pressure. A value of 1.18/10 ' mg/L at STP was estimated. 4 Beilstein, E4, Volume 1, part 2 page 694. 2. General Information on Exposure 2.1 Production Volume and Use Vinyl fluoride had an aggregated production and/or import volume in the United States between 1 to 10 million pounds during calendar year 2005. Industrial processing and uses for the chemical were claimed confidential. No commercial and consumer uses were reported for the chemical. 2.2 Environmental Exposure and Fate Vinyl fluoride is expected to have high mobility in soil. No biodegradation was available for the sponsored substance; however, a structural analog, vinyl chloride (CASRN 75-01-4) achieved 3- 16% of its theoretical biochemical oxygen demand (BOD) using a closed bottle (OECD 301D) test for volatile substances over a 4-week incubation period. Volatilization of vinyl fluoride is high given its Henry's Law constant. The rate of hydrolysis is expected to be negligible. The 6 ------- U.S. Environmental Protection Agency Hazard Characterization Document September, 2014 rate of atmospheric photooxidation is slow. Vinyl fluoride is expected to have moderate persistence (P2) and low bioaccumulation potential (Bl). The environmental fate characteristics of vinyl fluoride are summarized in Table 2. Table 2. Environmental Fate Properties of Vinyl fluoride1 Property Value CASRN 75-02-5 Photodegradation Half-life 1.9 days (estimated)2 Hydrolysis Half-life Stable Biodegradation 3-16% after 28 days (not readily biodegradable)3'4 Bioaccumulation Factor BAF = 2.3 (estimated)2 Log Koc 1.3 (estimated)2 Fugacity (Level III Model)2 Air (%) 32.7 Water (%) 65.8 Soil (%) 1.3 Sediment (%) 0.2 Persistence5 P2 (moderate) Bioaccumulation5 Bl (low) 1 DuPont Corporation. 2005. Revisions to Test Plan and Robust Summary for Fluoroethylene. Available online at http://www.epa.gov/chemrtk/pubs/summaries/fluretln/cl4972tc.htm as of April 16, 2012. 2U.S. EPA. 2012. Estimation Programs Interface Suite™ for Microsoft® Windows, v4.10. U.S. Environmental Protection Agency, Washington, DC, USA. Available online at http://www.epa.gov/opptintr/exposure/pubs/episuitedl.htm as of April 16, 2012. 3National Institute of Technology and Evaluation. 2002. Biodegradation and Bioaccumulation of the Existing Chemical Substances under the Chemical Substances Control Law. Available online at http://www.safe.nite.go.ip/english/kizon/KIZON start hazkizon.html as of April 16, 2012. 4Data for structural analog, vinyl chloride (CASRN 75-01-4). 5Federal Register. 1999. Category for Persistent, Bioaccumulative, and Toxic New Chemical Substances. Federal Register 64, Number 213 (November 4, 1999) pp. 60194-60204. Conclusion: Vinyl fluoride is a clear, colorless gas with high vapor pressure and high water solubility. It is expected to have high mobility in soil. Volatilization of vinyl fluoride is high. The rate of hydrolysis is expected to be negligible. The rate of atmospheric photooxidation is slow. Vinyl fluoride is not readily biodegradable. Vinyl fluoride is expected to have moderate persistence (P2) and low bioaccumulation potential (Bl). 3. Human Health Hazard A summary of health effects data for SIDS and other endpoints is provided in Table 3. The table also indicates where data for supporting chemical(s) are read-across (RA) to the sponsored substance. For complete SIDS data set for the supporting chemical, vinyl chloride 7 ------- U.S. Environmental Protection Agency Hazard Characterization Document September, 2014 (CASRN 75-01-4), see human health data at: http://www.chem.unep.ch/irptc/sids/OECDSIDS/VINYLCHL.pdf Acute Inhalation Toxicity Several studies are available for acute inhalation toxicity. The study summarized in the HPV Challenge submission is presented here. Vinyl fluoride (CASRN 75-02-5) Mice (strain, sex and group number size not specified) were exposed via inhalation to a "gaseous mixture" of vinyl fluoride. In the first of two experiments, mice were exposed to 45, 66, 70 or 100% vinyl fluoride in air for 4 hours and observed for up to 24 hours post-exposure. The mortality rate was 17, 31 and 100% at 45, 66 and 70% exposure concentrations, respectively. The median lethal concentration was 69%. In the second experiment, concentrations of 80 and 90% vinyl fluoride were mixed with pure oxygen and mice were exposed for an unspecified duration. The study authors concluded that in the first experiment, deaths occurred at all concentrations due to suffocation (lack of oxygen) rather than vinyl fluoride poisoning. In the second experiment, the summary noted that the vinyl fluoride did not oxidize and the results were similar to those obtained with tests in air. LCso = 690,000 ppm Repeated-Dose Toxicity Vinyl fluoride (CASRN 75-02-5) In a 90-day study, Crl:CD BR rats (15/sex/concentration) and Crl:CD-l(ICR)BR mice (15/sex/concentration) were exposed (whole-body) to vinyl fluoride vapors at concentrations of 0, 200, 2000 or 20,000 ppm (mean measured concentrations of 0, 198.2, 2005.1 and 19,841.2 ppm) for 6 hours/day, 5 days/week. The following parameters were evaluated: clinical signs, body weight, food consumption, ophthalmological examination, hematology, clinical chemistry and urinalyses parameters, organ weights, gross and histopathology. In addition, cell proliferation was evaluated in liver, kidney, lung, and nasal cavity tissues. Effects were limited to a concentration-related increase in cell proliferation in livers of all treated mice and rats and in olfactory mucosa of mice at all test concentrations. No effects were seen following clinical and ophthalmological examination; there were also no effects on body weights, food consumption or hematology and clinical chemistry. LOAEC = 200 ppm (based on cell proliferation in the liver of mice and rats and in the olfactory mucosa of mice) NOAEC = Not established Reproductive Toxicity Vinyl fluoride (CASRN 75-02-5) 8 ------- U.S. Environmental Protection Agency Hazard Characterization Document September, 2014 No specific reproductive toxicity studies are available for vinyl fluoride. (1) In the 90-day inhalation toxicity study mentioned previously, there were no effects on reproductive organs in rats (testes, epididymides, prostate, seminal vesicles, mammary gland, ovaries, uterus and vagina were examined histologically and testes and ovaries were weighed). (2) No effects were seen on reproductive organs in the inhalation carcinogenicity studies of vinyl fluoride in rats. However, in mice, an increased incidence of mammary gland adenocarcinoma and hyperplasia were observed. (3) Vinyl fluoride did not induce mutations in a dominant lethal mutation assay (see details below) in rats. (4) Vinyl fluoride did not induce unscheduled DNA synthesis (see details below) in rat spermatocytes. Vinyl chloride (CASRN 75-01-4, supporting chemical) In a two generation reproductive toxicity study via inhalation, Sprague-Dawley rats (30/sex/concentration) were exposed to vinyl chloride at 0, 10, 100 or 1100 ppm, 6 hours/day, 5days/week during premating and 6 hours/day, 7 days/week during gestation, lactation and postweaning. Evaluation for the parental animals included body weights, food consumption, and estrous cycling as well as fertility, reproductive performance, and sperm assessments. Both F1 and F2 pups were examined and weighed at birth and on several days during lactation. At weaning, one pup/sex/litter was randomly selected, sacrificed, and given a macroscopic examination. No adverse effect of the measured parameters was seen in the parental generations and no adverse effect of treatment was indicated in the F1 and F2 pups. Liver effects typical of vinyl chloride (increased weights, hypertrophy, and occurrence of altered hepatocellular foci) were noted in parental animals at 1100 and 100 ppm, but not at 10 ppm, with increased incidence occurring in the P2 as opposed to the PI animals. Whether this increased incidence in P2 animals was due to in utero or juvenile susceptibility (the PI animals were not exposed during these periods whereas the P2 animals were) or to a longer duration (P2 animals were exposed longer than were PI animals) is not clear. However, tumor incidence has been documented to increase at maturity among laboratory animals treated with vinyl chloride during the first 6 months of life when compared with those exposed during the second or third 6-month period of life. No effects on reproductive parameters were observed. See human health data at: http://www.chem.unep.ch/irptc/sids/OECDSIDS/VINYLCHL.pdf and IRIS evaluation at: http ://www. epa. gov/iri s/ sub st/1001 .htm NOAEC (reproductive toxicity) = 1100 ppm (highest concentration tested) Developmental Toxicity Vinyl chloride (CASRN 75-01-4, supporting chemical) (1) In a prenatal developmental toxicity study done in conjunction with the 2-generation reproduction toxicity study, pregnant Sprague-Dawley rats (25/concentration) were exposed (whole-body) via inhalation to vinyl chloride at 0, 10, 100 or 1100 ppm (approximately 0, 26, 9 ------- U.S. Environmental Protection Agency Hazard Characterization Document September, 2014 256 or 2816 mg/m3) for 6 hours/day on gestation days (GDs) 6 through 19. In dams, increased relative kidney weights were seen at 100 or 1100 ppm. Changes in body weight gain were not considered treatment-related. No statistically significant fetal malformations were observed, nor were developmental parameters affected. See human health data at: http://www.chem.unep.ch/irptc/sids/OECDSIDS/VINYLCHL.pdf LOAEC (maternal toxicity) = 100 ppm (based on kidney effects) NOAEC (maternal toxicity) = 10 ppm NOAEC (developmental toxicity) = 1100 ppm (based on no effects at the highest concentration tested) (2) In two separate prenatal developmental toxicity studies, pregnant Sprague-Dawley rats (16 - 31/concentration) were exposed to vinyl chloride via inhalation to concentrations of 0 (air) and 500 ppm or o (air) and 2500 ppm (with or without 15% ethanol in drinking water) for 7 hours/day, from GD 6 through 15. Decreased weight gain, decreased number of corpora lutea/dam and pregnancy wastage (the number of corpora lutea minus the number of implants) were found in dams exposed to 500 ppm. Decreased feed consumption and increased absolute and relative liver weight were found in animals exposed to 2500 ppm. A decrease in fetal body weight, an increase in crown-rump length and a significantly (p < 0.05) increased incidence of rib spurs were observed in fetuses exposed to 500 ppm, but not 2500 ppm. A significant (p < 0.05) increase in the incidence of unilateral or bilateral dilated ureters was found in fetuses exposed to 2500 ppm. In general, the presence of ethanol increased the incidence of observed effects. See human health data at: http://www.chem.unep.ch/irptc/sids/OECDSIDS/VINYLCIIL.pdf LOAEC (maternal toxicity) = 500 ppm (based on decreased body weight gain, decreased number of corpora lutea/dam and pregnancy wastage) NOAEC (maternal toxicity) = Not established LOAEC (developmental toxicity) = 2500 ppm (based on decreased fetal body weight, increased crown-rump length and increased incidence of rib spurs) NOAEC (developmental toxicity) = 500 ppm (3) In two separate prenatal developmental toxicity studies, pregnant CF-1 mice (7 - 26/concentration) were exposed to vinyl chloride via inhalation at 0 (air) and 50 (with and without 15% ethanol) or 0 (air) and 500 ppm (with and without 15% ethanol in drinking water) for 7 hours/day, from GD 6 through 15. Dams exposed to 500 ppm exhibited decreased weight gain, decreased feed consumption, decreased absolute liver weight and 17% mortality. There was an increase in the incidence of resorptions in dams exposed to 500 ppm. The total number of live fetuses/litter and fetal weights was significantly (p < 0.05) reduced in dams exposed to 500 ppm. Fetal crown-rump length was significantly (p < 0.05) increased at 50 ppm but not at 500 ppm. Statistically significant (p < 0.05) fetal skeletal tissue anomalies at 500 ppm included increased incidences of unfused or delayed ossification of sternebrae and delayed ossification of the skull; however, the authors concluded that these changes were within historical controls. In general, the presence of ethanol increased the incidence of observed effects. See human health data at: http://www.chem.unep.ch/irptc/sids/OECDSIDS/VINYLCIIL.pdf LOAEC (maternal toxicity) = 500 ppm (based on mortality, decreased weight gain, decreased feed consumption, decreased absolute liver weight) 10 ------- U.S. Environmental Protection Agency Hazard Characterization Document September, 2014 NOAEC (maternal toxicity) = 50 ppm LOAEC (developmental toxicity) = 2500 ppm (based on increased incidence of resorptions, decreased live fetuses/litter, decreased fetal weights and increased incidences of unfused or delayed ossification of sternebrae and delayed ossification of the skull) NOAEC (developmental toxicity) = 500 ppm (4) In two separate prenatal developmental toxicity studies, pregnant New Zealand White rabbits [5 (high dose) or 20 (low dose)/group] were exposed to vinyl chloride via inhalation at concentrations of 0 (air) and 500 ppm or 0 and 2500 ppm (with or without 15% ethanol in drinking water) for 7 hours/day from GD 6 through 18. The percentage of pregnant females was 100, 95 and 86% at 0, 500 and 2500 ppm, respectively. Decreased (p < 0.05) feed consumption, number of corpora lutea per dam, number of implantations per dam and number of live fetuses per litter was seen in animals exposed to 500 ppm but not at 2500 ppm. A statistically significant (p < 0.05) increase in the incidence of delayed ossification of the 5th sternebra was seen at 500 ppm but not at 2500 ppm. See human health data at: http://www.chem.unep.ch/irptc/sids/OECDSIDS/VINYLCHL.pdf NOAEC (maternal and developmental toxicity) = 2500 ppm (based on no dose-response of adverse effects observed) Genetic Toxicity — Gene Mutation In vitro Vinyl fluoride (CASRN 75-02-5) (1) In a reverse-mutation assay modified for gaseous mixtures, Salmonella typhimurium strains TA1535, TA1537, TA1538, TA98 and TA100 were exposed to vinyl fluoride at concentrations of 0, 1,5, 10 or 25% in the presence and absence of metabolic activation. Study details absent from the summary included information about cytotoxicity, criteria for determining positive and negative findings and statistical methods. Data for strain TA1538 were excluded due to contamination of culture. A slight increase in the frequency of histidine revertants was observed in the TA100 culture; however, the increase was less than 2-fold and was not concentration- related. No cytotoxicity or precipitation was observed at any concentration tested. Positive and negative controls were tested concurrently and produced an appropriate response. Vinyl fluoride was not mutagenic in this assay. (2) In several reverse-mutation assays of vinyl fluoride, various strains of Salmonella typhimurium were exposed up to concentrations of 52%. Vinyl fluoride induced statistically significant increases (P < 0.01) in mutation frequency (1.4 to 2.1 times negative control mutation frequencies) in three of the five assays in strain TA1535 with metabolic activation. VF did not induce reverse mutations in strains TA98, TA100, or TA1537 in the presence of metabolic activation, nor in any strain in the absence of metabolic activation (10th RoC, 2002). Vinyl fluoride was mutagenic in the presence of metabolic activation but not in the absence of metabolic activation. 11 ------- U.S. Environmental Protection Agency Hazard Characterization Document September, 2014 (3) In mammalian cell gene mutation test, Chinese hamster ovary (CHO)/HPRT cells were exposed to vinyl fluoride at concentrations of 0, 20, 40, 60, 80 or 100% in triplicate in the presence and absence of metabolic activation. Preliminary studies were conducted to determine cytotoxicity. Although no statistically significant increases in mutant frequencies were demonstrated in either trial with activation when analyzed separately, combined analyses indicated a statistically significant (p < 0.01) increase at the 60% level. A large standard deviation between the negative control values in the second trial made interpretation of the results difficult. Therefore, a third trial was conducted. The combined statistics of all three trials indicated significant increases in mutant frequencies at all concentrations (20 - 100% vinyl fluoride). A positive quadratic dose-response was also statistically evident. Vinyl fluoride was mutagenic in this assay. Genetic Toxicity — Chromosomal Aberrations In vitro Vinyl fluoride (CASRN 75-02-5) In mammalian cell chromosome aberration test, CHO cells were exposed to vinyl fluoride at concentrations of 0, 23, 48, 71.5 or 96.3% in the non-activated cytotoxicity assessment; 0, 27, 52.1, 61.3 or 97% in the activated cytotoxicity assessment; 0, 8.1, 42.9, 72.3 or 104.1%) in the non-activated chromosome aberration trial 1; 0, 8.8, 46.5, 77.8 or 111.4% in the non-activated chromosome aberration trial 2; 0, 8.3, 25.9, 49.6 or 75.1%> in the activated chromosome aberration trial 1; and 0, 12.3, 35.4, 63.3 or 91.3%> in the activated chromosome aberration trial 2. The negative control contained nitrogen and the positive control agents were ethylmethane sulfonate (EMS) and vinyl chloride. Cell cycle delay was seen following exposure to 96.3% vinyl fluoride (in nitrogen) without activation. With activation, moderate to severe cell cycle delay was observed at 52.1 and > 61.3%> vinyl fluoride, respectively. Equivocal chromosome aberration results were obtained following 5-hour non-activated treatments. Chromosome aberrations were induced after 2-hour treatments with activation at concentrations ranging from 8.3 to 63.3% vinyl fluoride. Vinyl fluoride induced chromosomal aberrations in this assay. In vivo Vinyl fluoride (CASRN 75-02-5) In mammalian bone marrow chromosome aberration test, Crl:CD-l(ICR)BR mice (15 - 18/sex/concentration) were exposed to atmospheres of vinyl fluoride gas in air at concentrations of 0, 94, 376 or 753 mg/L for 6 hours. Cyclophosphamide, dosed by intraperitoneal injection, served as the positive control. Approximately 24, 48 and 72 hours after initiation of exposure, mice were sacrificed (five per sex per time period for the control, low and intermediate dose groups, six per sex per time period for the high group). Immediately following sacrifice, the marrow from both femurs of each animal was excised and slides were prepared and examined. One thousand polychromatic erythrocytes (PCEs) per animal were scored for the presence of micronuclei. No clinical signs were observed prior to sacrifice. Male mice of the low and high exposure groups and female mice of the high exposure group exhibited weight loss. At the 24- hour sacrifice time, females showed a concentration-related trend in the proportion of micronucleated PCEs, although no single test concentration gave increases over controls. 12 ------- U.S. Environmental Protection Agency Hazard Characterization Document September, 2014 Females exposed to the intermediate (94 mg/L) and high (753 mg/L) concentrations of vinyl fluoride showed increases in the frequency of micronucleated PCEs as compared to controls with a concentration-related trend. Males also showed increased frequencies of PCEs; however, these increases were considered equivocal due to the sponsor's indication that the effect was not statistically significant. Vinyl fluoride induced chromosomal aberrations in this study. Genetic Toxicity — Other In vivo Vinyl fluoride (CASRN 75-02-5) (1) In the rodent dominant lethal test, male Crl:CD rats (40/group) were exposed to atmospheres of vinyl fluoride gas in air at concentrations of 0, 200, 2000 or 20,000 ppm for 6 hours/day for 5 days. A positive control group was exposed to triethylenemelamine. Males were mated with unexposed females beginning 2 days following exposure. This procedure was repeated weekly, using different females, for 8 consecutive weeks. Females were weighed and clinical signs recorded on GDs 0 and 14 and sacrificed on GD 14. The numbers of total implantations, resorptions, live and dead embryos and corpora lutea were determined, and preimplantation loss was calculated. Males were weighed and clinical signs were recorded daily during exposure and weekly thereafter. All males were sacrificed 10-11 days after the final day of mating. Testes were examined for gross abnormalities, weighed and preserved in Bouin's fixative, but microscopic examination was not performed. The vinyl fluoride exposure did not increase the frequency of dominant-lethal mutations, indicating that it was not mutagenic to germ cells in the male rat. Vinyl fluoride did not induce an increase in the frequency of dominant-lethal mutations in this assay. (2) In an unscheduled DNA synthesis (UDS) assay, male CDF(F-344)CrlBr rats (15/group) were exposed (nose-only) to vinyl fluoride via inhalation at concentrations of 0 or 20,000 ppm. At approximately 2, 6 or 24 hours after exposure, testicular cells were prepared from five animals in both the control and treatment groups. To determine whether vinyl fluoride inhibited DNA repair, testicular cells were cultured and incubated. Following incubation, cell viability was determined by trypan blue exclusion. Three slides per animal and 25 cells per slide were scored for a total of 75 cells per animal. Vinyl fluoride was not toxic to testicular cells, nor was UDS observed. Vinyl fluoride exposure did not induce unscheduled DNA synthesis in this assay. Additional Information Carcinogenicity Vinyl fluoride (CASRN 75-02-5) (1) In a two-year carcinogenicity study, Crl:CD BR rats (95/sex/concentration) were exposed (whole-body) to vinyl fluoride vapors at 0, 25, 250 or 2500 ppm for 6 hours/day, 5 days/week. 13 ------- U.S. Environmental Protection Agency Hazard Characterization Document September, 2014 There was a statistically significant decrease in survival of male and female rats at 250 and 2500 ppm compared to controls. The decrease in survival in male rats at 25 ppm was statistically significant while that in female rats was not statistically significant.. Slight decreases in mean body weight gain (6 - 15%) were observed in rats at 25 and 250 ppm, along with increased incidence of "weak" and "colored discharged eye(s)," as stated by the sponsor, in female rats at 25 ppm. At necropsy, concentration-related lesions included masses, nodules, discoloration and hemorrhage of the liver; mass/nodules and discoloration and hemorrhage of the lungs, and fluid in the peritoneal cavity; masses of the head, face and periaural area; and abscesses of the face. These lesions were attributed to secondary effects to vinyl fluoride induced neoplasms. The combined incidences of neoplastic lesions for male and female rats at 0, 25, 250 and 2500 ppm, respectively, were as follows: hepatic hemangiosarcoma (0/160, 13/160, 49/160 and 35/160), hepatocellular adenoma and carcinoma (5/160, 14/160, 19/160 and 15/160), foci of clear cell alteration (37/160, 49/160, 62/160 and 72/160), foci of basophilic alteration (35/160, 59/160, 64/160 and 90/160), sinusoidal dilatation (16/160, 65/160, 61/160, and 50/160) and Zymbal's gland tumors (0/160, 2/160, 4/160 and 23/160). Mortality related to vinyl chloride induced hepatic hemangiosarcoma became significant in the second year of the study. The total incidences of rats that died of hepatic hemangiosarcoma over the course of the study were 1/80, 2/80, 25/80 and 15/80 for male rats and 0/80, 7/80, 14/80 and 15/80 for female rat at 0, 25, 250 and 2500 ppm, respectively. Lesions secondary to hemangiosarcoma-induced hemorrhage and hemolysis included increased erythropoiesis in the spleen and bone marrow and eosinophilic droplets/pigment in renal tubular epithelium. Acute necrosis in the liver was likely the result of acute tissue hypoxia following hemorrhage into the peritoneal cavity. Metastatic hemangiosarcomas in the lungs were associated with pulmonary hemorrhage, edema and histiocytosis. (2) In another carcinogenicity study, Crl:CD-l(ICR)BR mice (95/sex/concentration) were exposed (whole-body) to vinyl fluoride vapors at 0, 25, 250 or 2500 ppm for 6 hours/day, 5 days/week for 18 months. Survival was decreased in male mice at 250 and 2500 ppm and in female mice in all treatment groups. Mean body weight gain was decreased by 17% in male mice exposed to 2500 ppm. At necropsy, concentration-related lesions included nodules, masses and discoloration of the lung; fluid in the pleural cavity; masses of the peritoneal cavity; hemorrhage, cysts, masses, discoloration and nodules of the liver; and mammary gland masses. Microscopically, these lesions were attributed to secondary effects of neoplasms; the combined incidences for male and female mice at 0, 25, 250 and 2500 pm, respectively, are as follows: bronchioloalveolar adenoma (20/162, 69/160, 99/160 and 109/162 ), bronchioloalveolar hyperplasia (3/162, 22/160, 53/160 and 76/162), hepatic hemangiosarcoma (1/162, 29/161, 67/160 and 74/162), hepatocellular hyperplasia (2/162, 36/160, 80/160 and 73/162) and mammary gland adenocarcinoma and hyperplasia (0/77, 22/76, 20/78 and 20/77). Early mortality was primarily related to hemorrhage from hepatic hemangiosarcoma. Lesions secondary to hemangiosarcoma-induced hemorrhage and hemolysis included increased erythropoiesis in the spleen and bone marrow and eosinophilic droplets/pigment in renal tubular epithelium. Acute necrosis in the liver was likely the result of acute tissue hypoxia following hemorrhage into the peritoneal cavity. Metastatic hemangiosarcomas in the lungs were associated with pulmonary hemorrhage, edema and histiocytosis. 14 ------- U.S. Environmental Protection Agency Hazard Characterization Document September, 2014 Conclusion: Acute inhalation toxicity of vinyl fluoride to mice is low. In 90-day repeated inhalation toxicity studies in rats and mice, vinyl fluoride showed concentration-related increases in cell proliferation in livers of all treated mice and rats, and in olfactory mucosa of mice at > 200 ppm; the NOAEC was not established. No specific reproductive toxicity studies are available with vinyl fluoride; however, no effects on the reproductive organs were seen in the 90- day inhalation study in rats. In an inhalation two-generation reproductive toxicity study in rats with the supporting chemical, vinyl chloride, no effects on reproductive parameters were observed at any concentration; the NOAEC for reproductive toxicity is 1100 ppm (highest concentration tested). No developmental toxicity studies are available for vinyl fluoride. In prenatal inhalation developmental toxicity studies in rats and mice with the supporting chemical, vinyl chloride, the following treatment-related developmental effects were observed at 500 ppm and above: increased fetal resorption, decreased corpora lutea/dam in rats, decreased live fetuses/litter in mice, increased fetal loss or pregnancy wastage in rats, decreased fetal body weight in rats and mice, increased fetal crown-rump length in rats, increased incidences of rib spurs and dilated ureters in rats, increased incidences of unfused or delayed ossification of sternebrae in mice and an increased incidence of delayed ossification of the skull in mice. The NOAEC for maternal and developmental toxicity was not established in rats; the NOAEC for maternal and developmental toxicity in mice is 50 ppm and 500 ppm, respectively. In rabbits exposed to the supporting chemical vinyl chloride, decreased feed consumption, number of corpora lutea per dam, number of implantations per dam and number of live fetuses per litter and an increase in the incidence of delayed ossification were seen at 500 ppm but not at 2500 ppm; the NOAEC for maternal and developmental toxicity was 2500 ppm (highest concentration tested). Vinyl fluoride is mutagenic in bacteria and mammalian cells in vitro and it induced chromosomal aberrations in vitro and in vivo. Vinyl fluoride showed no effects on spermatocytes or germ cells in the unscheduled DNA synthesis and dominant lethal assays in rats, respectively. Vinyl fluoride increased the incidence of tumors in rats and mice. The International Agency for Research on Cancer (IARC) states that "for practical purposes, vinyl fluoride should be considered to act similarly to the human carcinogen vinyl chloride". Table 3. Summary of the Screening Information Data Set under the U.S. HPV Challenge Program - Human Health Data Endpoint SPONSORED CHEMICAL Vinyl fluoride (75-02-5) SUPPORTING CHEMICAL Vinyl chloride (75-01-4) Acute Toxicity Inhalation LCso (ppm) 690,000 Repeated-Dose Toxicity NOAEC/LOAEC Inhalation (ppm) NOAEC = Not established LOAEC = 200 Reproductive Toxicity NOAEC/LOAEC (ppm) No Data NOAEC = 1100 (RA) (rat; 2-gen) NOAEC = 1100 (highest concentration tested) 15 ------- U.S. Environmental Protection Agency Hazard Characterization Document September, 2014 Table 3. Summary of the Screening Information Data Set under the U.S. HPV Challenge Program - Human Health Data Endpoint SPONSORED CHEMICAL SUPPORTING CHEMICAL Vinyl fluoride Vinyl chloride (75-02-5) (75-01-4) Developmental Toxicity NOAEC/LOAEC Inhalation (ppm) No Data (rat) Maternal Toxicity NOAEC = Not established NOAEC = Not established LOAEC = 500 LOAEC = 500 Developmental Toxicity NOAEC = 500 NOAEC = 500 LOAEC = 2500 LOAEC = 2500 (mouse) (mouse) Maternal Toxicity NOAEC = 50 NOAEC = 50 LOAEC = 500 LOAEC = 500 Developmental Toxicity NOAEC = 500 NOAEC = 500 LOAEC = 2500 LOAEC = 2500 (RA) (rabbit) (mouse) NOAEC = 2500 Maternal Toxicity NOAEC = 2500 (highest concentration tested) Developmental Toxicity NOAEC = 2500 NOAEC = 2500 (RA) (highest concentration tested) Genetic Toxicity - Gene Mutation In vitro Positive Genetic Toxicity - Chromosomal Aberrations Positive - In vitro Genetic Toxicity - Chromosomal Aberrations Positive - In vivo Genetic Toxicity - Chromosomal Aberrations Other UDS Negative - Dominant Lethal Negative - Additional Information Carcinogenicity Positive in rats and mice - Measured data in bold; RA = read-across; - indicates endpoint not addressed for this chemical 4. Hazard to the Environment A summary of the ecotoxicity data for SIDS and other endpoints is provided in Table 4. The table also indicates where data for supporting chemicals are read-across (RA) to untested members of the category. 16 ------- U.S. Environmental Protection Agency Hazard Characterization Document September, 2014 Acute Toxicity to Fish Vinyl chloride (CASRN 75-01-4, supporting chemical) (1) Zebra fish (Brachydanio rerio) were exposed to vinyl chloride (> 99% purity) at nominal concentrations of 0, 31, 63, 125, 250 or 500 mg/L under semi-static conditions for 96 hours. Mean measured concentrations were 1.25, 34.9, 59.4, 128, 220 and 388 mg/L. All fish exposed to 388 mg/L died within 48 hours and 70% of fish exposed to 220 mg/L died by 96 hours. Aberrant behavior was observed after 3 hours of exposure to 220 and 388 mg/L. 96-h LCso = 210 mg/L Acute Toxicity to Aquatic Invertebrates and Toxicity to Aquatic Plants No adequate data are available for the sponsored or the supporting chemical. Conclusion: The 96-h LCso value for fish exposed to vinyl fluoride is 210 mg/L, based on the supporting chemical (vinyl chloride). Adequate aquatic invertebrate and algal toxicity test data are not available for vinyl fluoride or vinyl chloride. Table 4. Summary of the Screening Information Data Set as Submitted under the U.S. HPV Challenge Program - Aquatic Toxicity Data Endpoint SPONSORED CHEMICAL Vinyl Fluoride (CASRN 75-02-5) SUPPORTING CHEMICAL Vinyl Chloride (CASRN 75-01-4) Fish 96-h LCso (mg/L) No Data 210 (RA) 210 Aquatic Invertebrates 48-h ECso (mg/L) No adequate data Aquatic Plants 72-h ECso (mg/L) (biomass) No adequate data - Bold = experimental data (i.e., derived from testing); RA = read across; - indicates that endpoint was not addressed for this chemical 5. References 10th Report on Carcinogens (2002) Report on carcinogens background document for vinyl fluoride found at: http://ntp.niehs.nih.gov/ntp/newhomeroc/roclO/vf.pdf 17 ------- |