Fetal exposure

Jones KL. Developmental pathogenesis of defects associated with prenatal cocaine exposure fetal vascular disruption. Clin Perinatol 1991 18(l) 139-46. 

Other toxicological effects that may be associated with exposure to benzyl chloride based on animal studies are skin sensitization and developmental embryo and/or fetal toxicity. A 1980 OSHA regulation has estabhshed a national occupational exposure limit for benzyl chloride of 5 mg/m (1 ppm). Concentrations of 160 mg/m (32 ppm) in air cause severe irritation of the eyes and respiratory tract (68). 

Developmental Effects. Adverse effects of methyl parathion on hirman fetal development have not been reported. Based on studies in animals, such effects appear to be possible if pregnant women were exposed during the first trimester to high concentrations of methyl parathion that resulted in significant depression of cholinesterase levels, particularly if concomitant signs and symptoms of organophosphate intoxication occur. Such an exposure scenario may occur with occupational exposure, exposure in homes or offices illegally sprayed with methyl parathion, or accidental exposure to methyl parathion, but is less likely as a result of low-level exposure. 

Data from a single study in dogs suggest that hepatic first-pass metabolism may limit systemic availability of the parent compound following oral exposure (Braeckman et al. 1983). Placental transfer of methyl parathion was demonstrated in pregnant rats 1-3 days before parturition. Thirty minutes after administration, both methyl parathion and methyl paraoxon were found in fetal brain, liver, and muscle methyl parathion, but not methyl paraoxon, was detected in placenta and maternal liver (Ackermann and Engst 1970). Methyl parathion binds reversibly to serum albumin, but is readily distributed to the tissues (Braeckman et al. 1980, 1983). 

Arbuckle TE, Sever LE. 1998. Pesticide exposures and fetal death A review of the epidemiologic literature. Crit Rev Toxicol 28 229-270. 

Majdic, G., Sharpe, R.M., and Oshaughnessy, PJ. et al. (1996). Expression of cytochrome P450 17 alpha-hydroxylase/C 17-20 lyase in the fetal rat testis is reduced by maternal exposure to exogenous estrogens. Endocrinology 137, 1063-1070. 

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