Behavioral Effects in Adults

It is apparent from the literature that the numerous sources of Pb result in widespread environmental pollution and contamination of food and beverages. Further, when exposure to Pb occurs in the workplace the potential for Pb intake increases considerably. The prevalence of occupational Pb exposure in a wide range of American industries was well-established over 40 yr ago, with estimates that approximately 1.5% of all workers were exposed to significant amounts of Pb. Similar estimates of occupational Pb exposure have been recently made in Finland and Denmark. Grandjean has compiled a summary of those industrial settings that hold the potential for exposure to hazardous levels of Pb as well as those with less significant levels of exposure. 

Measurements of blood Pb levels have been traditionally regarded as the best indicator of the risk of Pb poisoning and the most meaningful in monitoring workers exposed to Pb. Manifest symptoms of Pb toxicity in the occupationally exposed worker reirely occur at blood Pb levels below 80 [xg/dL. In a survey of 26 industrial operations conducted by the National Academy of Sciences, 10-35% of occupationally exposed workers had blood 

Pb levels of 100 [Jig/dL or more. Evidence from other sources (see Grand) ean ) has suggested that measurement of zinc protoporph3 in (ZPP) and, at lower exposure levels, delta-aminolevulinic acid dehydratase (ALAD) may have higher predictive validity than blood Pb analysis. Additional biological indices of Pb exposure have also been discussed by Posner et al.  

Personality changes have also been observed in adults following exposure to Pb. An increased prevalence of depression, hostility, and general dysphoria has been observed by Repko et al, while Hanninen et al. found that low level exposure to Pb may induce disturbances in subjective feelings of well being. 

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