Lead-Based Battery Used in Electric Car May Pose Hazards

By Peter Passell
The New York Times

May 9, 1995

For years, electric cars and vans powered by lead-based batteries have been promoted as a way to reduce health-damaging urban smog. But now the potential risk from production of the batteries, long quietly acknowledged, is drawing more careful scrutiny from scientists, and their findings are alarming.

In a forthcoming study, three researchers at Carnegie Mellon University in Pittsburgh suggest that emissions from mining, smelting and recycling the lead needed for a large fleet of electrical vehicles would pose serious threats to public health.

Thus, while Government regulations requiring the sale of electric cars are intended to improve public health by limiting smog, they may have the indirect effect of exposing thousands of people living or working near industrial sites to toxic doses of lead.

"We're talking about very real health hazards," said Robert Hahn, an environmental economist at the American Enterprise Institute. "This could be the kiss of death for electric vehicles."

The potential risk from lead batteries illustrates a fundamental conundrum for policy makers. Aggressive efforts to clean up the air, water and land often drive rapid changes in technology, which in themselves may prove hazardous. Even seemingly more benign battery technologies based on other materials could have unintended consequences.

"Loading the environment with any primary metal is going to lead to problems," said Dr. Ellen Silbergeld, a toxicologist at the University of Maryland Medical School.

Exposure to low levels of lead can harm the brains of young children, reducing intelligence and impairing neurobehavioral development, studies have found. Very severe exposure can cause coma, convulsions and death.

The electric car question has its origins in the Clean Air Act, which set tough health standards for ozone exposure. To meet them, California, New York and Massachusetts are demanding the introduction of "zero emissions vehicles" by 1998, with 10 percent of all new cars meeting the zero-emissions test by the year 2003.

The only zero-emissions vehicles close to mass production are powered by electricity that is stored by conventional means. "First-generation electric cars will have lead-acid batteries," said Bob Hayden, executive director of the Electric Vehicle Association of the Americas.

Electric cars have already run a gantlet of controversy. Auto makers maintain that vehicles using current technology, which have a very limited range, could not be sold at cost -- even in the modest numbers mandated by state rules. Thus, they say, they will be forced to "cross-subsidize" buyers, raising the prices of conventional internal combustion cars to cover the difference.

Many economists who share the policy makers' sense of urgency in containing urban smog are nonetheless critical of the zero-emissions requirement because it does not give auto makers the flexibility to meet the targeted emissions level for automobiles with less radical technology. And even some environmentalists acknowledge problems underlying the electric car remedy. They note that the extra electricity generated to charge car batteries will come from power plants that also generate pollution.

"Of course there are trade-offs," said David Driesen of the Natural Resources Defense Council.

In an article to appear this month in the journal Science, Lester Lave, an economist at Carnegie Mellon, along with Chris Hendrickson and Francis McMichael, his colleagues in engineering, estimate a life-cycle scenario for emissions associated with lead-acid batteries. Their scenario, "available technology," is based on the specifications of the General Motors Impact vehicle, now being tested around the country. The study was supported largely by the National Science Foundation, with other funds from I.B.M. and A.T.& T.

To create a best-case scenario, the researchers imagine a "goal technology" car with batteries that use one-third as much lead to generate the same amount of power, yet last twice as long. They use data from the Bureau of Mines, an agency of the Interior Department, and the Environmental Protection Agency to estimate the amount of lead that would be lost in the environment during the life-cycle of the battery from both scenarios.

According to their calculations, an "available technology" car would indirectly generate 1,350 milligrams of lead emissions for each kilometer (about five-eighths of a mile) traveled. The "goal technology" car does much better, at 120 milligrams of lead per kilometer. But a car using even this relatively clean technology would push six times as much lead into the environment as a tiny Geo Metro burning gasoline with the lead additives that were gradually eliminated in the 1980's.

The form of the pollutant matters, of course. Lead from leaded gasoline went out the vehicle's tailpipe; the Carnegie Mellon scientists concede that five-sixths of the emissions from smelting and recycling would be more manageable solids and liquids.

As important, emissions from leaded gasoline were concentrated in urban areas, while emissions from the battery life-cycle would be focused near smelters and recyclers. "Location isn't everything," says Rob Stavins, an economist at Harvard's Kennedy School of Government, "but it's almost everything."

Dr. Silbergeld, the toxicologist, is not mollified. "Lead particles can move long distances," she said. "This is potentially a global problem."

She also worries that in their zeal to encourage the recycling of lead batteries, regulators have underestimated the risks from recycling plants, many of which operate near urban areas.

Thus, while it may be technically possible to clean up lead smelting and reprocessing, there is little indication that the Government has the will or skill to do the job. Nor is there hard evidence about how much cleaner lead technologies would add to the already high cost of electric vehicles.

The magnitude of the health problem depends, of course, on the number of vehicles powered by lead batteries. But even the relatively modest penetration implied by the state mandates could generate large-scale emissions.

If just 5 percent of the 200 million vehicles in the United States were powered by batteries made entirely of lead processed by responsible recyclers, Mr. Lave estimates that an extra 21,000 tons of lead would be released each year into the environment. That would nearly double the amount now lost in smelting and manufacturing.

Environmentalists who want to keep the pressure on Detroit to build electric vehicles expect that technology and economics will eventually favor materials more benign than lead. But that is only a hope.

Batteries based on nickel, nickel-cadmium, sulfur-sodium and lithium all show some promise, as do hybrid systems combining smaller batteries with flywheels or capacitors to meet peak power demands. But they are likely to remain more expensive than lead-acid systems, which in turn cost far more to build and operate than the cleanest-running internal combustion engines.

"We haven't closed the door on other technologies," said Chris Preuss, a spokesman for Chrysler, "but it's not looking good."

David Hawkins, a senior lawyer for the Natural Resources Defense Council and an architect of the Clean Air Act, thinks the risks implied by forcing electric cars into the nation's vehicular fleet are worth taking. The alternative, he said, is dependence on super-clean gasoline engines that require careful, and politically unpopular, inspection and maintenance.

"We think it makes more sense to try to pick winners than to settle for losers," Mr. Hawkins said.

But others are critical of using environmental policy to force industry to invent new technologies in general, and the zero-emissions mandate in particular. "Regulation leads to innovation," says George Eads, a consultant in Washington and a former chief economist at General Motors, "but it is often the wrong innovation."

Mr. Eads also maintains that the strict timetable for zero-emissions vehicles, meant as a wake-up call for Detroit, has already had a perverse effect. Since auto makers are under immense pressure to put electric cars on the road that will not haunt them with repair or safety problems, "the mandate puts a premium on using the most conservative technological option," he said -- in this case, lead-acid batteries.

"Getting rid of lead in gasoline was one of the great public health triumphs of our generation," Mr. Lave said. "It would be a tragedy if we reversed the benefits in the name of environmentalism."

Correction: May 13, 1995
A chart in Science Times on Tuesday about lead pollution arising from the making of lead batteries for electric vehicles misstated an estimate of the average amount of indirect lead emissions generated by an electric car using available technology. It is 1.350 grams per kilometer, not 1,350.