CHICAGO - Lead is the No. 1 environmental health hazard for children, but a new study indicates that more than 30 million American adults may be at risk of premature death because of past exposure to the metal.
The study, reported in late November in the Archives of Internal Medicine, found that people who had elevated blood levels of lead earlier in life have a 46 percent increased rate of mortality from all causes later on, indicating that children may carry a legacy of lead toxicity as they age.
Children are especially vulnerable to the effects of lead, and it has long been known that lead can cause mental retardation in those exposed to relatively modest levels. But once children reached adulthood it was thought they would be more resistant to the damage.
Enforcement urged
Experts say the findings underscore the importance of enforcing laws regulating the removal of lead paint from older houses, where children can ingest lead in dust and paint chips.
"Clearly, this argues for much more aggressive abatement and enforcement of these laws, as we've been doing," said Dr. Peter L. Beilenson, health commissioner in Baltimore, where recent efforts have resulted in significant drops in the number of children with lead poisoning. "There's even better reason now to reduce your kid's risk of living in this. Not only does it cause behavioral and other problems, but it also apparently causes an increase in mortality."
Researchers said the new study also suggests that federal standards for the amount of lead adult workers can have in their blood may be set dangerously high.
"This is a very important new study," said Dr. Peter Orris, director of the Occupational Health Services Institute at the University of Illinois at Chicago. "It indicates that there is increased cardiovascular and cancer mortality in adults at blood lead levels we haven't been concerned about before."
The research also sheds light on the reason African-Americans - who tend to be exposed to more lead in the environment - have significantly increased rates of some diseases, especially high blood pressure, which has been linked to elevated lead levels.
Lead's danger to children led to the gradual elimination of leaded gasoline and lead paint, the two major sources of lead in the environment. Lead was banned from residential paint in 1978, and leaded gasoline was phased out by 1986. Blood lead levels have since plummeted greatly.
