Toxicokinetics and bioavailability of oral and intravenous 1,1-dichloroethylene*1, *2

Identification of Critical Biological Parameters Affecting Gastrointestinal Absorption

“…Comparison of the results of Putcha et al (1986) for dichloroethylene with those of D 'Souza et al (1985) for trichloroethylene suggested an effect of solubilities on GI absorption, as discussed previously. The water solubilities of tetrachloroethylene (0.048 g/100 ml) and trichloroethylene (0.100 g/100 ml) are similar and both considerably less than the solubility of 1,1-dichloroethylene (0.25 g/100 ml) or dichloromethane (1.96 g/100 ml).…”

“…The reported effect of food in the GI tract on GI absorption varies with different studies, but fed animals generally exhibited a slower uptake of chemical during the initial phase (D'Souza et al, 1985) or a longer half-time of elimination over the longer term than fasted animals (Putcha et al, 1986), which the authors interpreted as indicating delayed absorption. These effects of food on GI absorption are likely due to adsorption of a portion of the chemical to food components or dissolving of a portion of the chemicals in the lipid component of the food.…”

“…Both dichloroethylene (Putcha et al, 1986) and trichloroethylene (D'Souza et al, 1985) showed peak blood levels within 10 minutes after dosing in 50 percent aqueous ethlene glycol. This is in contrast to experiments where dichloroethylene was administered in corn oil, in which peak concentrations in exhaled air were observed in 30 to 60 minutes (McKenna et al, 1978), and for tetrachloroethylene in corn oil, which yielded a peak blood concentration in 60 minutes (Pegg et al, 1979).…”

“…After the oral administration of volatile halogenated hydrocarbons, the time courses of both the blood concentration and the concentration of these chemicals in exhaled air exhibit biphasic decreases (Putcha et al, 1986;Chieco et al, 1981;D'Souza et al, 1985;McKenna et al, 1978;Pegg et al, 1979). from the GI tract in two phases, an initial rapid phase and a slower long-term phase, and effects of GI contents on both phases are apparent.…”

“…The bioavailability of dichloroethylene was determined by Putcha et al (1986). They reported no significant differences in the area under the curve of the plot of blood concentration versus time for intravenously-and orally-dosed dichloroethylene in aqueous polyethylene glycol over a 10-fold range of dose (10 to 100 mg/kg) for fasted and fed rats.…”