Researchers commissioned by the Defense Department said Monday that decades-old limits on lead exposure are inadequate to protect the health of workers on military firing ranges.
Moreover, the National Academy of Science reported, lead from ammunition fired on Army, Navy and Air Force ranges in the last five years has "frequently exceeded" those limits, "in some cases by several orders of magnitude."
Sen. Ben Cardin expressed concern about the report's implications for workers at Maryland installations with firing ranges, such as Aberdeen Proving Ground in Harford County.
"They're at risk," the Maryland Democrat said. "This report shows that exposure to lead from firing ranges is a health hazard, and we can do a better job of protecting the public health."
Officials at the Army Test and Evaluation Command at Aberdeen Proving Ground could not be reached Monday for comment.
The Pentagon had asked the academy to assess whether it should continue to rely on standards for lead exposure that were set by the Occupational Safety and Health Administration in 1978.
The National Research Council, the academy's investigative arm, said it should not.
Under the 1978 standards, exposure to 50 micrograms of lead per square meter of air, or a blood lead level of 40 micrograms per deciliter, was considered acceptable.
But the council's review of research since then showed that blood lead at much lower levels may cause neurologic, cardiovascular, reproductive and other problems.
The council also reported "compelling evidence" of effects on the development of offspring in utero or during breastfeeding, which it said "raises additional concerns about exposures of women of childbearing age."
The council recommended the Defense Department reduce the level of blood lead considered acceptable, but it did not propose a new standard.
Different organizations have recommended that levels as low as 10 micrograms per deciliter be considered elevated, and that levels in pregnant women be kept below 5 micrograms to reduce the risk of spontaneous abortion.
The council said it did not have enough information about the blood lead levels of range workers to determine their potential health risks. The Air Force said its firing range personnel had levels under 40 micrograms; data for the other branches were not available.
But because the ranges for all services have frequently exceeded OSHA's airborne lead limit, the council said, the Defense Department should track and analyze blood levels to guide safety procedures.
A Pentagon spokeswoman expressed appreciation for the report.
"We will be using our internal occupational health expertise in applying the academy's recommendations," Air Force Lt. Col. Melinda Morgan said. "Until the new policy and procedures are developed, we will also be looking for near-term actions needed to protect the health of our people."
Sen. Barbara Boxer, the chairwoman of the Senate Committee on Environment and Public Works, said she would follow up with Defense Secretary Leon Panetta.
"Everyone makes everything complicated," said the California Democrat, who appeared with Cardin at a Capitol Hill news conference. "It's not complicated. We want to protect our people from exposure to these dangerous toxins. And we will do everything in our power to ensure that our families are protected from toxins that harm the human body."
Boxer and Cardin spoke of possible alternatives to lead ammunition. Boxer said the Air Force has been firing lead-free ammunition during small-arms training. Cardin spoke of the possibility of using simulations.
Cardin said his concerns extend beyond the firing ranges to the communities that surround them.
"We want to make sure that we have the appropriate regulatory environment to protect the public health," he said. "Let the agencies have the authority that they need, and let's be judged by best science, and let's keep politics out of it."
Cardin noted that he had clashed with the Pentagon over environmental issues around Fort Meade and Fort Detrick. Now he praised the military.
"I really want to be complimentary," he said. "Their primary mission is to make sure we have a ready force to protect our nation. And they need to be more sensitive to their footprint and the impact they have on the community. They've shown that in this case.
"They asked for the study. They're now asking for OSHA to revise their rules so that the Department of Defense can be in compliance with public health issues as it relates to the use of the their firing ranges. So I think they're taking the necessary steps."