Effects of pre- and post-natal lead on affective behavior and learning in the rat.

Literature relevant to the relationship between early ingestion of inorganic lead and subsequent hyperactivity in rodents is discussed. Original research in the area is presented. Rats so exposed were not hyperactive in any of the situations investigated or under any of the dosage regimens employed. They did show hypoactivity in the open field when dosed over a prolonged period. Using a new behavior measure, lead-treated rats were found to be less active than controls in the passive avoidance situation. The possible utility of this new measure for behavioral and developmental toxicology is discussed. It is concluded that the available evidence does not support the contention that a meaningful relationship exists between early lead ingestion and hyperactive behavior. It is suggested that future research may more profitably be directed to assessing the effects of lead ingestion on behavior in stressful or fear provoking situations.