Current OSHA guidelines are probably inadequate, researchers say
TUESDAY, Sept. 8 (HealthDay News) -- Exposure to lead over a lifetime may increase the risk of dying from heart disease, new research shows.
Researchers analyzed lead concentrations in the blood and bones of 868 mostly white men from the Boston area who participated in a veterans' aging study.
The men, whose average age was 67 at the start of the study, had lead concentrations in their blood and the bones of the patella (kneecap) and tibia (shin) measured over a nine-year period. During the course of the study, 241 died.
Researchers found that men who had the highest concentrations of lead in their bones had a six times greater chance of dying from cardiovascular disease than men with the lowest concentrations.
Men with the highest levels of lead had a 2.5 times greater chance of dying from all causes than men with the lowest levels.
"Cumulative exposure to lead, even in an era when current exposures are low, represents an important predictor of cardiovascular death," said study author Marc Weisskopf, an assistant professor of environmental health and epidemiology at the Harvard School of Public Health in Boston. "The findings with bone lead are dramatic. It is the first time we have had a biomarker of cumulative exposure to lead, and the strong findings suggest that it is a more critical biomarker than blood lead."
The study appears in the Sept. 8 issue of Circulation.
Typically, lead exposure is measured through blood samples. For instance, the Occupational Safety and Health Administration (OSHA) and the National Health and Nutrition Examination Surveys use blood to measure lead.
But blood, because it has a half life of about 30 days, reveals recent exposure. To determine cumulative exposure, bone is the better method, according to the study.
Bone has a half life ranging from years
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