Effects of pre-natal and continued lead exposure on activity levels in the mouse

Binghamton heterogeneous (HET) stock mice were exposed to 0.5% lead acetate solution from conception through adulthood. Activity was measured in an open field, shuttle-box, and the home cage. Independent groups of animals were tested at several ages in the light (day) and dark (night). Despite significant blood-lead level differences between the control and lead treated animals, developmental and activity differences between groups were restricted to selected measures. The lead-treatment appeared to alter only jumping in the open field and some consummatory behaviors observed in the home cage. This research does not provide support for a model which proposes a simple, direct relationship between low-level lead toxicity and hyperactive behavior. It is suggested that future research focus on the specific conditions under which activity is measured. Animal parallels to a human "hyperactive disorder" may need to be reformulated in terms of attention deficits which mark the childhood disorder.