hexachlorobutadiene - Davidborowski.com
hexachlorobutadiene - Davidborowski.com
hexachlorobutadiene - Davidborowski.com
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HEXACHLOROBUTADIENE 30<br />
2. HEALTH EFFECTS<br />
The highest NOAEL values and all LOAEL values from each reliable study for neurotoxicity in each<br />
species and duration category are recorded in Table 2-2 and plotted in Figure 2-2.<br />
2.2.2.5 Reproductive Effects<br />
No studies were located regarding reproductive effects in humans after oral exposure to<br />
<strong>hexachlorobutadiene</strong>.<br />
In animals, fertility was reduced 100% in Wistar-derived rat dams administered 150 mg/kg/day<br />
<strong>hexachlorobutadiene</strong> during a 10-week study. The mean litter size and the resorption rate did not<br />
differ significantly from controls in dams fed 15 mg/kg/day during an 18-week study (Harleman and<br />
Seinen 1979). The actual total exposure time for this study is not clear; the rats were exposed for at<br />
least 10 weeks at the high dose and 12 weeks (of an 18-week study) at the low dose. No<br />
determination of a reliable LOAEL or NOAEL value was possible for this study. In another study,<br />
fertility, gestation, viability, and lactation indices were <strong>com</strong>parable in treated and control groups of<br />
Sprague-Dawley rats at dose levels of 20 mg/kg/day for 148 days (Schwetz et al. 1977). No<br />
significant changes were seen in sperm count or incidence of abnormal sperm in mice exposed to<br />
<strong>hexachlorobutadiene</strong> (19 mg/kg/day) for 13 weeks (NTP 1991; Yang et al. 1989). Lifetime exposures<br />
up to 20 mg/kg/day did not reveal treatment-related lesions in the reproductive organs (Kociba et al.<br />
1977a).<br />
The highest NOAEL values and all LOAEL values from each reliable study for reproductive effects<br />
in each species and duration category are recorded in Table 2-2 and plotted in Figure 2-2.<br />
2.2.2.6 Developmental Effects<br />
No studies were located regarding developmental effects in humans after oral exposure to<br />
<strong>hexachlorobutadiene</strong>.<br />
In animal studies, rat dams were fed <strong>hexachlorobutadiene</strong> at dose levels of 15 mg/kg/day during<br />
gestation (as part of an 18-week study). Rat pup weights were reduced at birth and weaning.<br />
However, embryotoxicity and teratogenicity were not observed at this dose (Harleman and Seinen<br />
1979). In another study, body weight was decreased (p < 0.05) on day 21 of lactation in rat pups