EPA Opts Not to Regulate Dioxins in Sewage Sludge

By J.R. Pegg

WASHINGTON, DC, October 21, 2003 (ENS) - The U.S. Environmental Protection Agency (EPA) has decided not regulate dioxins in sewage sludge that is applied as fertilizer. The agency says the presence of dioxins in the sludge does not pose a significant risk to human health or the environment, but critics say the decision is irresponsible.

"The EPA is required by law to protect the public from toxic pollutants like dioxins," said Nancy Stoner, director of the Natural Resources Defense Council's (NRDC) Clean Water Project. "This decision shows the agency under this administration has forgotten its mission."

It was a lawsuit filed more than a decade ago by the NRDC and Oregon environmentalists that prompted the EPA's action on the issue. Part of the settlement agreement ordered the agency to announce a final regulation by October 18, 2003.

There is little doubt that dioxins, which are persistent organic pollutants produced by waste incineration and other industrial processes, can present serious health and environmental concerns.

These toxics are known to cause cancer and diabetes, damage neurological, immune and endocrine systems - Americans generally have a cancer risk of one in 10,000 from the dioxins they already have in their bodies.

More than 3 million tons of treated sewage sludge are applied to U.S. land as fertilizer. (Photo courtesy Pennsylvania Department of the Environment)

Under a 1993 Clean Water Act rule, sewage sludge can be applied to land if it is sufficiently treated to limit concentrations of certain chemicals and reduce disease causing pathogens.

Some 5.6 million tons of sewage sludge are used or disposed of annually in the United States, with some 60 percent applied as fertilizer to farms, parks, golf courses, lawns and forests.

In its decision issued Friday, the agency said new analysis shows the risks from dioxins in sewage sludge are too low to justify regulation, in particular amid data that indicates dioxin levels in treated sewage sludge are declining.

The move abandons a 1999 proposal by the agency to add dioxin limits to the standards governing the chemical concentrations of land applied sewage sludge.

The EPA's decision drew support from the Association of Metropolitan Sewerage Agencies (AMSA), which says the agency's analysis reflects its own.

"This final rule reaffirms that sound science remains the bedrock on which solid environmental policy is made," said AMSA's Executive Director Ken Kirk. "The science behind EPA's decision is compelling."

Some municipalities apply treated sewage sludge - known as biosolids - to forests. (Photo courtesy Washington's King County)

The EPA's analysis showed that for this theoretical population, "only 0.0003 new cases of cancer could be expected each year or only 0.22 new cases of cancer over a span of 70 years."

"The risk to people in the general population of new cancer cases resulting from sewage sludge containing dioxin is even smaller due to lower exposures to dioxin in land-applied sewage sludge than the highly exposed farm family which EPA modeled," according to the agency.

But there is more to the issue than the cancer risk, Stoner says.

"The EPA itself has said that the non cancer risks of dioxins are so high that it can not even calculate a 'safe' or acceptable level of exposure," she said. "To us that says EPA should keep dioxins out of our food, and that means, among other things, regulating sewage sludge."

Critics add that a 2002 report by the National Research Council found a lack of health related information about populations exposed to treated sewage sludge. The report described the EPA's standards that govern land application of the material as based on outdated science.