Lead poisoning: altered urinary catecholamine metabolites as indicators of intoxication in mice and children.

Whether neuropsychological impairment occurs in children with increased lead absorption who are without clinical symptoms is of current concern. This tissue, which involves potentially large numbers of children, remains unresolved, in part because of the lack of sensitive biochemical indicators of the effects of lead on the nervous system. In experimental subclinical lead poisoning in mice, significant increases in homovanillic acid and vanillylmandelic acid have been found in brain and urine. In children with increased lead absorption, these acids were meaured in urine collected quantitatively under controlled dietary conditions; preliminary results show fivefold increases in the daily output of these compounds. These data suggest that the altered catecholamine metabolism also occurs in children.