Lead exposure among workers renovating a previously deleaded bridge: Comparisons of trades, work tasks

Airborne and surface lead exposures were evaluated for construction trade g roups at a previously deleaded bridge renovation site in the midwestern Uni ted States. Although all lead-based paint should have been removed, old lay ers of leaded paint were still present on some sections of the bridge. Iron workers performing metal torch cutting had the highest exposures (188 mug/m (3)), followed by workers engaged in clean-up operations and paint removal (p < 0.001). Respirators were most frequently worn by workers with the grea test lead exposures; however, laborers performing clean-up operations had e xposures to lead dust of 43 <mu>g/m(3) and often wore no respiratory protec tion. Wipe samples revealed that almost all contractor vehicles were contam inated with lead. Heavy equipment operators with low airborne lead exposure had the highest levels of surface contamination in personal vehicles (3600 mug/m(2)). Laborers cleaning structural steel with compressed air and iron workers exposed to lead fumes from cutting had the highest concentrations o f lead dust on clothing (mean 4766 mug/m(2)). Hand-washing facilities were provided, but were infrequently used. No separate clothes changing facility was available at the site. The potential for "take-home" contamination was high, even though this site was thought to be relatively free of lead. Con struction contractors and their workers need to be aware that previous dele ading of a site may not preclude exposure to significant amounts of lead.