Toxicity of mild prenatal carbon monoxide exposure.

Rats prenatally exposed to a low concentration of carbon monoxide which results in carboxyhemoglobin levels equivalent to those maintained by human cigarette smokers, show reduced birth weight and decreased weight gain. Neuro-behavioral and biochemical testing of the offspring reveals lower behavioral activity levels through the preweaning period, altered central catecholamine activity, and reduction in total brain protein at birth.