Effects of toluene exposure during gestation on neurobehavioral development of rats and hamsters

Pregnant rats and hamsters were exposed to toluene vapor (800 mg/m3) 6 h daily from gestation days 14 to 20, and 6 to 11, respectively. Growth, neuromotor development and performance of the offspring in behavioral tasks were assessed. In rats, toluene exposure increased the number of litters with low birth weight pups. Male rat offspring exposed to toluene displayed shorter latencies than male controls to choose one side of a T maze in a spontaneous alternation test. Hamsters exposed to toluene performed worse in a rotating rod test. These results confirm toluene fetotoxicity in rats and suggest an effect on exploratory behavior which may be related to hormonal changes in early life. Neuromotor effects of exposure of hamsters to toluene in utero deserve further investigation.