NEUROBEHAVIORAL EFFECTS FROM EXPOSURE TO DENTAL AMALGAM HG-DEGREES - NEW DISTINCTIONS BETWEEN RECENT EXPOSURE AND HG BODY BURDEN

Potential toxicity from exposure to mercury vapor (Hg degrees) from de ntal amalgam fillings is the subject of current public health debate i n many countries. We evaluated potential central nervous system (CNS) toxicity associated with handling Hg-containing amalgam materials amon g dental personnel with very low levels of Hg degrees exposure (i.e., urinary Hg <4 mu g/l), applying a neurobehavioral test battery to eval uate CNS functions in relation to both recent exposure and Hg body bur den. New distinctions between subtle preclinical effects on symptoms, mood, motor function, and cognition were found associated with Hg body burden as compared with those associated with recent exposure. The pa ttern of results, comparable to findings previously reported among sub jects with urinary Hg >50 mu g/l, presents convincing new evidence of adverse behavioral effects associated with low Hg degrees exposures wi thin the range of that received by the general population.