EPA Plans to Restrict Toxic Airborne Lead

While leaded gasoline is history, about 1,300 tons of lead a year is emitted into the air from smelters, iron and steel foundries, and general aviation gasoline, the EPA estimates.

Once it is airborne, lead can be inhaled.

Or, after it settles out of the air onto surfaces, lead can be ingested - the main route of human exposure. Once in the body, lead is rapidly absorbed into the bloodstream and can affect many organ systems.

Children are particularly vulnerable, the EPA has said repeatedly. Exposures to low levels of lead early in life have been linked to effects on intelligence, learning, memory and behavior.

To protect public health, the EPA proposed Thursday to tighten the primary standard by up to 93 percent.

"By tackling lead emissions, EPA is keeping America's clean air progress moving forward," said EPA Administrator Stephen Johnson, announcing the new revised standard.

Doe Run Lead Smelter at Herculaneum, Missouri (Photo credit unknown)

The existing standard of 1.5 micrograms of lead per cubic meter of air would be cut to a level within the range of 0.10 to 0.30 micrograms per cubic meter.

The current standard of 1.5 micrograms per cubic meter of air is "not sufficient to protect public health with an adequate margin of safety," the EPA says in its draft revision.

The agency is taking comment on alternative levels within a range from less than 0.10 to 0.50 micrograms per cubic meter.

Under the new rule, monitors for lead would be required near large sources of lead emissions and in urban areas with more than one million people.

Some environmentalists say the new EPA lead standard is not strict enough. Avinash Kar, project attorney with the public health program of the Natural Resources Defense Council called the proposal "long overdue but flawed."

"According to EPA projections, emissions of 60 pounds of lead from a single pollution source could cause a median loss of up to three IQ points in children," said Kar. "Thousands of children across the United States live near lead plants emitting more than 60 pounds of lead every year. In fact, some plants emit tons of lead annually."

"By proposing a limit stricter than the current standard that was set in 1978, EPA is making progress in limiting lead exposure," he said, "but this standard still falls short of what's needed to protect the public."

The largest lead smelter in the United States is the Doe Run Company Lead Smelter and Refinery at Herculaneum, Missouri. Lead concentrates are smelted to yield 225,000 tons per year of refined lead.

Taking the lead out of gasoline has cut lead emissions by 98 percent since 1980 nationwide, the EPA says, and now average levels of lead in the air are far below the level of the 1978 standard.

But whatever lead remains is toxic. More than 6,000 studies since 1990 have examined the effects of lead on health and the environment, the agency says. "Evidence from health studies indicates that lead in the blood can cause harm at much lower levels than previously understood."

Exposure to lead is associated with a broad range of health effects, including harm to the central nervous system, cardiovascular system, kidneys and immune system.

Lead also can cause toxic effects in plants and can impair reproduction and growth in birds, mammals and other organisms.

EPA is proposing that the secondary standard, to protect the environment, be identical to the primary standard.

Located 25 miles south of St. Louis on the Mississippi River, Doe Run's Herculaneum Smelting Division is the largest smelter in the United States. It operates a round-the-clock producing lead and by-products from lead concentrates.

The smelter's products are used in everyday applications such as computer screens, car batteries, protective equipment and other specialties.

"Smelter employees are also achieving the lowest blood-lead levels in the history of the division," the company says on its website.

This year Doe Run is putting up a new fence around its Herculaneum smelter.

"Our goal for the new fence is twofold. We want to add an additional margin of protection by increasing the distance between us and our nearest neighbor. The green zone will allow us to achieve that goal. We also want to limit access to the plant to control traffic on the roadways and to provide a more secure facility," said Gary Hughes, general manager of the Herculaneum smelter.

"We appreciate the community"s support as we continue to minimize the impact of our operations," Hughes said. "Doe Run has a long history here." He said the company is committed to working with the city and with the community.

The EPA will accept public comment for 60 days after the proposal on lead is published in the Federal Register. The agency will hold two public hearings on June 12, 2008 - one in St. Louis and one in Baltimore.

EPA must issue a final decision on the lead standard by September 15, 2008.

Find details about the proposal and public hearing information at: http://www.epa.gov/air/lead

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