LEAD LEVELS IN MARYLAND CONSTRUCTION WORKERS

A cross-sectional study of unionized construction workers not currentl y known to be performing lead work was conducted. Participants complet ed an interviewer-aministered questionnaire obtaining information abou t demographics, work history: other possible sources of lead exposure and health status (including hypertension, noise-induced hearing loss and renal disease). Blood was then obtained via venipuncture for whole blood lead level, hematocrit and free erythrocyte protoporphyrin dete rmination. Two hundred and sixty-four Maryland construction workers ha d median whole blood lead determinations of 7 mu g/dl and mean values of 8.0 mu g/dl, with a skewed distribution ranging from 2 to 30 mu g/d l. None were currently engaged in known lead work. Blood lead levels w ere significantly higher for the 124 who had 'ever' worked in demoliti on (8.8 mu g/dl vs. 7.2 mu g/dl, p =.004), and for the 79 who had ever burned paint and metal and welded on outdoor structures compared to t he 48 who had done none of these activities (8.6 mu g/dl vs. 6.8 mu g/ dl, p =.01). The 58 workers who had ever had workplace lead monitoring performance had higher lead levels (9.7 vs. 7.5 mu g/dl, p =.003) Blo od lend levels increased with age, and cigarette smoking. African Amer icans (N = 68) had higher lead levels (9.1 vs. 7.5 mu g/dl, p =.01). t here were only two women in the study, one with a lead level of 21 mu g/dl and one, 7 mu g/dl. Blood lead levels did not predict either syst olic or diastolic blood pressure in this population. However there was a significant interaction between race and lead as predictors of bloo d pressure, with blacks demonstrating a trend-significant correlation, and whites showing a nonsignificant but negative association. Demolit ion and hotwork on outdoor structures are known to cause acute episode s of lead poisoning. They also appear to cause slight but persistent i ncreases in blood lead levels. Future workplace regulation should reco gnize and seek to maintain the law baseline now apparent even in urban , East Coast, construction workers. (C) l997 Wiley-Liss,lnc.