The previous standard hadn’t been changed since 1978, said Cathy Milbourn, a spokesperson for the EPA.

“As science evolves and the linkage between air quality and health evolves, the Clean Air Act said that the EPA needs to evaluate the standard of health and change it as necessary,” said Cheryl Newton, the acting director of the air and radiation division for the Region 5 branch of the EPA.

Region 5 encompasses Michigan, Illinois, Indiana, Minnesota, Ohio and Wisconsin.

The major contributors to airborne lead include primary and secondary lead smelters, iron and steel foundries, industrial, commercial and institutional boilers, waste incinerators, glass and cement manufacturing and some small piston aircraft, Milbourn said.

These are all contributors to lead in the air but the Lead National Ambient Air Quality Standard measures lead concentrations over an area such as a county, not from individual facilities, she said.

According to the Michigan Air Emissions Reporting System, the only lead emissions produced by MSU were from the power plant.

The highest level during the last nine years was in 2004, with 2.1 tons of lead being emitted into the air. By 2006, this number had fallen to .00728 tons. Numbers for 2007 and 2008 are unavailable.

This falls below the .06-ton limit required to even report the emissions, said Allan Ostrander, an environmental quality specialist for the Department of Environmental Quality, or DEQ.

The East Lansing Wastewater Treatment Plant is the only other producer of lead emissions in East Lansing. The most recent available data, from 2003, showed no lead in its emissions.

Another measure the EPA wants to implement is requiring air quality monitoring centers near urban areas with a population of 500,000 or more, Milbourn said.

The only monitoring center in Michigan is in Wayne County, she said.

However, places that produce emissions are required to have air permits. These permits require the producers of the emissions to report levels of lead and other pollutants when they break a certain level. The DEQ keeps track of pollutants in emissions.

Lead in gasoline used to be a major contributor to lead emissions, but it was outlawed in 1995, according to a 1995 statement from the EPA.

“Regular” gas used to have about four grams of lead per gallon, according to the statement.

“I think lead in the air is definitely much more under control now,” said Dr. Bill Atchison, a professor of pharmacology and toxicology. “Now there’s much less of a problem with lead as an air pollutant.”

Lead is particularly harmful to children and can lead to negative effects on learning and memory. Most of the problems with lead exposure to children has to do with lead-based paint rather than lead emissions, Atchison said.

“(There’s) nothing lead does that’s good. On the other hand, you can’t keep removing every little trace of it,” Atchison said, “The question becomes what is the relative risk of having such and such amount of lead; we don’t really know what the lowest possible level is that you might see effects.”