DEVELOPMENTAL TOXICITY OF DIMETHYL SULFATE BY INHALATION IN THE RAT

Dimethyl sulfate (DMS; CAS No. 77-78) is a colorless, oily liquid whic h is used as a chemical intermediate and as a reactant in producing po lyurethane resins. In this study, groups of pregnant Cr1:CD(R)BR rats were exposed, nose-only, to either 0.1, 0.7 or 1.5 ppm DMS by inhalati on for 6 hr/day from Days 7 through 16 of gestation (day in which copu lation plug was detected was designated Day 1G). A control group of pr egnant rats was exposed simultaneously to air only. All female rats we re euthanized on Day 22G and the fetuses were examined. A suppression of both food consumption and the rate of body weight gain was seen in the 0.7 and 1.5 ppm groups. No unusual clinical signs were seen in rat s exposed to DMS. None of the reproductive parameters was altered in a ny of the groups and no statistically significant fetal effects were d etected. DMS is not a developmental toxin in the rat following inhalat ion exposures up to 1.5 ppm during the period of major organogenesis.