A review of persistent, low-grade lead challenge: neurological and cardiovascular consequences.

Although acute toxicity following heavy intake of lead (Pb) is a well-established clinical entity, the harmful effects of persistent, low-dose challenge, a situation commonly found among the general population, is uncertain. The major dangers of persistent, low-dose challenge that have been hypothesized are controversial: first, mentation and behavioral perturbations and second, development of hypertension with its consequences on the cardiovascular system. Accordingly, one cannot exclude some contributions from persistent Pb exposure to chronic disease and the aging process. Despite these potential adversities, many sources for Pb contact still remain with us. Current estimates are that 10-50% of American children (over 3-4 million) harbor unsafe levels according to present-day standards. Therefore, it is reasonable to conclude that more work is needed in this area. Clearcut evidence concerning the deleterious influence of Pb on the nervous and/or cardiovascular-renal systems would lead to greater attempt to lessen exposure, to ameliorate symptomatology by providing supplemental agents which obviate the unwanted effects of Pb (iron, calcium, zinc), and to consider therapy with binding agents, like CaNa2EDTA, in the afflicted.