Lead poisoning has been found in surprisingly high numbers of California workers, particularly in high-risk industries in Los Angeles, two state studies have revealed.
In articles published in this month’s issue of the American Journal of Public Health, officials at the state Department of Health Services report finding excessive lead exposure to workers in a handful of high-risk occupations, noting that monitoring practices to detect lead in the workplace environment are inadequate.
Under a state law effective Jan. 1, 1987, state medical laboratories performing tests for levels of lead in blood have been required to report the findings to the Department of Health Services. In one study of those cases, at least 5,000 workers were found to have elevated blood lead levels that were, in some cases, near toxic.
The survey showed that most of the exposed individuals were male and a disproportionate percentage, 44%, Latino. The study showed that 81% were residents of Los Angeles County, where many manufacturing processes using lead are based.
Most of the individuals were workers for lead smelters, battery manufacturers and brass foundries. Construction, radiator repair, pottery and ceramics manufacturing and firing ranges accounted for the remainder.
About half of the workers were not in routine medical monitoring programs.
In the second study by researchers at the state’s Occupational Health Program, only 2.6% of lead-using industries in the state reported they have done environmental monitoring for lead and only 1.4% have done routine biological monitoring programs.
In a third, unpublished study, tests showed at least 2,500 California children have potentially toxic levels of lead in their blood.
“There is more of a problem than people thought there was,” said Dr. Kenneth Kizer, state health director. “The biggest problem is the awareness, getting doctors to test kids and think about it as a potential issue. You have to test for it.”
As for workplace exposure, laws designed by the U.S. Occupational Safety and Health Administration to protect workers from lead exposure have been overlooked, said Dr. Philip J. Landrigan of Mt. Sinai Medical Center in New York, in an editorial accompanying the articles.
“Lead remains a serious problem in American workplaces,” Landirgan said. “These reported numbers, disturbing as they are, appear to represent but a fraction of the total problem, inasmuch as only 1.4% of lead-using industries in California have developed biological monitoring programs for their lead-exposed workers.”
The lack of monitoring among California industries suggests that cases of occupational lead poisoning may be seriously underestimated, the study says.
“I think in the workplace the problem is ignorance,” Kizer said. “It’s not knowing the laws, on the part of workers and operators. Where you’re seeing problems is not with the big companies, it’s with the smaller operations where you don’t have the focus on health and safety.”
In larger facilities, monitoring was more prominent. “The problem is big, but varies by industry, with the larger, unionized companies more likely to have monitoring programs,” said Dr. Jon Rosenberg of the Occupational Health Surveillance and Evaluation Program.
Almost 80% of battery manufacturing employees work in job classifications that have been monitored, compared to only 1% of radiator repair workers.
But, said Landrigan, “the number of OSHA inspectors in the field must be increased. These inspectors must be allowed to levy severe fines for repeated or willful violations. Criminal penalties must be used much more frequently than heretofore to punish repeated and willful violators.”
According to Kizer, standards for lead exposure have been changed in recent years as research showed that lower levels than previously expected can cause neurological damage. Few studies have looked at potentially dangerous lead exposure using the new, more sensitive criteria for toxicity.
“We weren’t totally surprised by what we found, but by the same token, we didn’t have a basis for knowing what it should be,” Kizer said.
But the studies are surprising because lead poisoning is traditionally viewed as a problem in the Northeastern part of the United States where many industries using lead are based and where older homes contain lead-based paint.
It is difficult to know if California residents have any greater risk to lead exposure than other states because the California studies used the more sensitive levels for lead exposure, Kizer said.
But, he said, lead exposure can be easily reduced by enforcement of OSHA regulations. Among children, most lead exposure comes from living near industries using lead or from lead-based paint in homes.