Mercury Exposure from Exterior Latex Paint

Abstract

Abstract In the United States, mercury has been routinely used as a biocide to preserve exterior latex paint. Although the concentration of mercury in exterior latex paints can be up to 1500 mg/L, mercury exposure from these paints has never been studied. We performed this investigation to determine the extent of mercury exposure from the outdoor application of exterior latex paints. To assess mercury exposure we compared air and urinary mercury concentrations of 13 professional male painters with those of 29 men having other occupations (nonpainters). The painters used two brands of exterior latex paint that contained mercury. The median concentration for the four paint samples obtained was 570 mg/L. The median air mercury concentration was higher for painters (1.0 μg/m3; range, nondetectable [ND], 4 μg/m3) than for nonpainters (ND; range, ND, 3 μg/m3); p = 0.0004. The median urinary mercury concentration was nearly twice as high for painters (9.7 μg/L; range, 5.9–20.4 μg/L) than for nonpainters (5.0 μg/L; range, 2.6–11.6 μg/L); p = 0.0001 (normal range < 20 μg/L). Among painters, urinary mercury concentrations increased with the percentage of time spent applying exterior paint (Pearson r = 0.6). These data suggest increased mercury exposure among professional painters who use mercury-containing exterior latex paint outdoors.