hexachlorobutadiene - Davidborowski.com
hexachlorobutadiene - Davidborowski.com
hexachlorobutadiene - Davidborowski.com
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HEXACHLOROBUTADIENE 11<br />
2. HEALTH EFFECTS<br />
reactions, asthma, or chronic bronchitis. As these kinds of health effects data be<strong>com</strong>e available and<br />
methods to assess levels of significant human exposure improve, these MRLs will be revised.<br />
A User’s Guide has been provided at the end of this profile (see Appendix A). This guide should aid<br />
in the interpretation of the tables and figures for Levels of Significant Exposure and the MRLs.<br />
2.2.1 Inhalation Exposure<br />
2.2.1.1 Death<br />
No studies were located regarding death in humans after inhalation exposure to <strong>hexachlorobutadiene</strong>.<br />
In animals, all mice that were exposed to vapors of 50 ppm <strong>hexachlorobutadiene</strong> for 5 days died, but<br />
no deaths occurred at 10 ppm (NIOSH 1981).<br />
2.2.1.2 Systemic Effects<br />
No studies were located regarding cardiovascular, gastrointestinal, musculoskeletal , or dermal/ocular<br />
effects in humans or animals after inhalation exposure to <strong>hexachlorobutadiene</strong>. Limited data are<br />
available on hepatic effects in humans and on the respiratory and renal effects of <strong>hexachlorobutadiene</strong><br />
in animals. These effects are discussed below. The highest NOAEL value and all LOAEL values<br />
from each reliable study for systemic effects in each species and duration category are recorded in<br />
Table 2-l and plotted in Figure 2-l.<br />
Respiratory Effects. Respiratory rates were decreased in mice exposed to vapors of<br />
<strong>hexachlorobutadiene</strong> at concentrations of 155 ppm or greater for 15 minutes. The authors<br />
characterized the responses as a reaction to nasal irritation (de Ceaurriz et al. 1988). Nasal irritation<br />
and respiratory difficulty was also reported in rats exposed to vapors at a concentration of 250 ppm<br />
for 2 days (4 hours/day) or 100 ppm for 12 days (6 hours/day) (Gage 1970). Breathing difficulty<br />
occurred even with exposure to 25 ppm for 15 days (6 hours/day).