Decreased Fetal Weights in Rats Exposed to Sidestream Cigarette Smoke

Pregnant Sprague-Dawley rats were exposed to sidestream Cigarettesmoke (SS) for 6 hr a day, at a concentration of 1 mg/m³ ofrespirable total suspended particulate material (TSP) on Days3, 6–10, and 13–17 of pregnancy. Controls were keptin an identical chamber without smoke exposure. The animalswere killed on Day 20 of gestation. No differences were foundin maternal body weight gain or average daily food consumptionbetween the smoke-exposed and control groups. The numbers offetuses and of implantation sites per litter were comparableamong the groups. None of the pups showed any gross malformationsand no difference was found between controls and SS-exposedpups when examined for reduced skeletal ossifications. However,there was a small but significant reduction in mean pup weight.We conclude that intermittent exposure of rats to sidestreamcigarette smoke at concentrations severalfold greater than thoseencountered in smokey public indoor environments causes intrauterinegrowth retardation.