Prevalence of elevated blood leads and exposure to lead in construction trades in Iowa and Illinois

Background Despite lowering of the permissible exposure level for lead in c onstruction from 200 to So mu g/m(3) in 1993, excessive lead exposure conti nues to be a problem. Relatively little data are available from the Midwest ern U.S. on the environmental lead concentrations generated during various construction activities and the potential for worker exposure. This study c haracterized the prevalence of blood lend concentrations in high-risk const ruction trades in Iowa/lllinois, and identified risk factors for occupation al exposure to lead in these construction workers. Methods A sample of 459 workers was selected from the total population of a ll union members from trade groups of painters, plumbers/pipefitters, ironw orkers, laborers, and electricians. Participants completed an interviewer-a dministered questionnaire obtaining information on demographics, symptoms, occupational history, work practices, personal protective equipment, and tr aining. Venous blood samples were collected from each participant and analy zed for blood lead (using atomic absorption spectroscopy) and free erythroc yte protoporphyrin levels. Results Blood lean levels (BLLs) of construction workers ranged from 0.1 to 50 mu g/dL. Geometric mean blood lead concentrations by trade group were: laborers (7.6 mu g/dL, n = 80); painters (5.9 mu g/dL, n = 83); ironworkers (5.2 mu g/dL, n = 87); plumbers (4.4 mu g/ dL, n = 82); electricians (2.4 mu g/dL, n = 91). Blood lead levels for painters and laborers were signific antly higher than other trade groups, and levels for electricians were sign ificantly lower (p < 0.01). Participants reported working primarily on comm ercial and industrial projects including new construction, renovation, and demolition. There were significant differences between the types of project s performed by different trade groups with laborers performing more highway /bridge renovation (p < 0.01), and plumbers reporting more residential remo deling (p = 0.05), repair of water lines containing lead (p = 0.04), or wor k an lead joints (p < 0.01). In addition to trade, elevated blood lead leve ls were associated with the type of construction project (especially bridge renovation and residential remodeling) and activities that include welding , cutting rivet busting. The age of the home in which the worker lived, and hobbies such as casting/smelting lead for bullets or sinkers, were also im portant risk factors. Compliance with OSHA's Construction Lead Standard, an d implementation of good occupational health and safety practices in genera l, was poor. Conclusions Blood lead levels of 459 construction workers differed by the t ype of trade, type of project and specific job activity owing to difference s in the inherent exposure potential of each task. Although the numbers of workers performing lead abatement projects were small, the trend for lower BLL in this group provides evidence that training, implementation of engine ering controls, and proper use of personal protective equipment such as res pirators is effective in controlling lead poisoning.