hexachlorobutadiene - Davidborowski.com
hexachlorobutadiene - Davidborowski.com
hexachlorobutadiene - Davidborowski.com
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HEXACHLOROBUTADIENE 67<br />
2. HEALTH EFFECTS<br />
chronic inhalation MRL. This data need can be evaluated after the results of the suggested acute- and<br />
intermediate-duration research be<strong>com</strong>es available.<br />
No epidemiological studies of <strong>hexachlorobutadiene</strong> are available. The occurrence of renal tumors<br />
after chronic oral exposure in rats suggests carcinogenicity may be an area of concern following<br />
occupational exposure to <strong>hexachlorobutadiene</strong> and long-term exposures from waste sites.<br />
Genotoxicity. No information is available on the genotoxic effects of <strong>hexachlorobutadiene</strong> in<br />
humans. Following exposure to <strong>hexachlorobutadiene</strong>, results were negative in in vivo rat and<br />
Drosophila tests that evaluated gene mutation and chromosomal damage (NIOSH 1981). The results<br />
were negative in in vitro tests evaluating gene mutation (De Meester et al. 1980; Haworth et al. 1983;<br />
Reichert et al. 1983; Vamvakas et al. 1988a) and DNA repair in Salmonella tests (with and without<br />
metabolic activation), and positive in mammalian assay systems using Syrian hamster cells<br />
(Schiffmann et al. 1984); the overall results were not consistent. Studies of <strong>hexachlorobutadiene</strong><br />
metabolites have indicated that some of the cysteine derived metabolites are mutagenic while others<br />
are not (Wild et al. 1986). Additional studies of the genotoxicity of intermediary metabolites are<br />
needed.<br />
Reproductive Toxicity. No data are available on the reproductive toxicity of <strong>hexachlorobutadiene</strong><br />
in humans. Hexachlorobutadiene did not cause adverse reproductive effects in mice or rats after<br />
inhalation or oral exposures, even at dose levels causing kidney and liver damage (Harleman and<br />
Seinen 1979; Kociba et al. 1977a; NIOSH 1981; NTP 1991; Saillenfait et al. 1989; Schwetz et al.<br />
1977). No data are available on the reproductive toxicity of <strong>hexachlorobutadiene</strong> after dermal<br />
exposure. Based on existing data in animals, it does not appear that exposure to the <strong>com</strong>pound would<br />
pose any significant risk to human reproduction.<br />
Developmental Toxicity. No studies were located regarding developmental effects in humans.<br />
Inhalation and oral studies in rat pups revealed that <strong>hexachlorobutadiene</strong> is fetotoxic, but not<br />
embryotoxic or teratogenic, at dose levels that are also maternally toxic (Harleman and Seinen 1979;<br />
Saillenfait et al. 1989; Schwetz et al. 1977). Additional oral studies in another species would be<br />
useful in clarifying the apparent lack of significant effects of <strong>hexachlorobutadiene</strong> on development.<br />
Systemic toxicity studies in rabbits suggest there is potential for dermal absorption to