Lead levels increase long after exposure stops, according to University of Pittsburgh research announced today.
Older workers with past occupational exposure to high levels of lead are at increased risk for the lead recirculating into their blood later in life, according to the study published in the current issue of Archives of Environmental and Occupational Health.
"Our study found that even workers with no current workplace exposure to lead -- but who have had considerable past exposure -- show increasing levels of lead in their blood as they age," Lisa A. Morrow, lead author and associate professor of psychiatry and psychology at the Western Psychiatric Institute and Clinic of UPMC, said in a news release.
Lead is a neurotoxin that can cause developmental and mental problems. Previous studies have shown that 90 to 95 percent of lead is stored in the bones and, with aging, bones demineralize and the lead can be recirculated into the blood stream.
Morrow's team studied 58 men, ranging from 40 to 76, with prior workplace exposure to lead. On average, none had worked with lead for the preceding 10 years. The older workers had the highest levels.
"Lead attacks many systems in the body," said Morrow. "The most important target is the central nervous system. Increased measures to prevent exposure will be necessary to achieve the optimal goal of zero blood lead in the U.S. in the next decade."
