Work and Blood Lead Relationships Among Bridge Workers;Final rept

摘要

OSHA's most recent lead in construction standard projected that a 4-fold reduction in air-lead concentration during certain work activities (i.e. from a typical value of 200 microgram m(sup -3) to 50 microgram m(sup -3) would avoid substantial illness among workers. However, the effectiveness of lead health protection programs that address requirements under this standard has remained largely unknown until the research presented in this project. This research characterizes the sources and pathways of airborne lead exposure during bridgework, develops an exploratory model and applies the model toward an analysis of data collected during a large-scale lead health protection intervention. Over 30 different tasks were identified that produce elevated level of lead in the air (average values range from less than 30 microgram m(sup -3) to almost 10000 microgram m(sup -3)). Blood lead levels among almost 2000 painting, ironwork, general craft and professional workers enrolled in a model lead health protection program designed to monitor and prevent workers from absorbing lead during these high-exposure tasks were summarized for years 1992-1995. For blasters and ironworkers, CRISP, which stands for Connecticut Road Industry Surveillance Project, maintained substantially lower blood lead levels in 1994 than levels found among workers with the same job title who conducted work outside of Connecticut during the same year.