Ban the Land Application of Sewage Sludge

The Boston Common is one of the oldest public parks in the country and anchor to Boston’s green space. It is also a dumping ground for sewage sludge. What was deemed too dangerous for the ocean is now called good for the land. The ruse is that the Environmental Protection Agency (EPA), which is responsible under the Clean Water Act to set regulations for sewage sludge use or disposal, has somehow made sludge “safe.”

Sewage sludge is the product of municipal wastewater treatment. Often thought to consist of only “human waste,” sewage sludge in fact contains organic, inorganic, and biological pollutants from commercial, industrial, and household wastes, and compounds added to and formed during treatment processes.

Millions of dry tons of sludge go on land every year. Why? Because it is the cheapest and most politically manageable disposal option since Congress banned ocean dumping of the material in 1991.

When ocean dumping was ruled out, the EPA adopted land disposal as its official sludge policy. To garner public acceptance for the practice, the agency coined the word “biosolids” for sewage sludge that has been treated to meet its regulatory requirements for land application. It was the linguistic detoxification of a hazardous waste. The agency has gone to extraordinary effort to propagate the euphemism.

But EPA and industry propaganda is being challenged by an alarming number of reports from people who say they or their friends or families were made sick by exposure to sewage sludge. What is making them sick? Synthetic organic chemicals? Pathogens? Dioxins? Or some combinations of the thousands of chemicals that end up in the sludge? No one knows for sure. The agency looked at 411 pollutants in sludge before deciding on regulations that govern 9 metals and nothing more. Call it the “Don’t look, can’t tell” policy. EPA has spent millions to tell us how safe sludge is, while not funding a single epidemiological study or a dime on tracking complaints about sludge-related illnesses.

When synthetic organic chemicals were considered for regulation in 1993, EPA’s risk assessments concluded that they do not pose significant risks and so need not be regulated, but others disagree. For example, in studies conducted by the two researchers, Robert Hale and Mark LaGuardia, high concentrations of polybrominated diphenyl ethers, a chemical used in flame retardants and related to PCBs, and nonylphenols, a product of the degradation during wastewater treatment of surfactants used in detergents, were detected in sewage sludge [1]. If both chemicals were regulated, it could significantly curtail the land applications of sludge.

Researchers at the University of Georgia published a study in the British medical journal, BMC Public Health, about self-reported illnesses among residents living near land application sites [2]. Their research indicated a pattern of chemical irritation from exposure to dusts and other airborne contaminants followed by bacterial infections of the skin and respiratory tract. Affected residents appeared to be at particularly high risk of infection with Staphylococcus aureus, a pathogen that tends to invade irritated or inflamed tissue. The report showed that the prevalence of S. aureus infections was approximately twenty-five times higher than infections among hospital patients, a recognized risk group for this pathogen.

The regulations that govern sewage sludge are meant to protect public health and the environment. They fall short according the National Research Council [3], the Centers for Disease Control and Prevention [4], the Inspector General of the EPA [5], and the countless sludge victims across the country.

In a report about the EPA’s sludge rules issued in April 2002, the agency’s Office of the Inspector General said, "EPA cannot assure the public that current land application practices [of sewage sludge] are protective of human health and the environment [6]."

Whether bagged in tidy little pellets and sprinkled on public parks or spewed in muddy globs on agricultural soil, sewage sludge remains a hazardous waste and its disposal on land should be stopped.

Laura Orlando

Resources

1. Have risks associated with the presence of synthetic organic contaminants in land-applied sewage sludges been adequately assessed? Robert C. Hale and Mark J. La Guardia, New Solutions: Journal of Environmental and Occupational Health, forthcoming.

2. Interactions of pathogens and irritant chemicals in land-applied sewage sludges (biosolids), David L Lewis1, 2 , David K Gattie3 , Marc E Novak2 , Susan Sanchez4 and Charles Pumphrey, BMC Public Health 2002 2:11

3. Biosolids Applied to Land: Advancing Standards and Practices, National Research Council, Washington DC, National Academy Press, July 2002.

4. Workers Exposed to Class B Biosolids During and After Field Application, NIOSH Hazard ID, HID 10, DHHS (NIOSH) 2000-158, National Institute for Occupational Safety and Health, Centers for Disease Control and Prevention, August 2000.

5. Biosolids Management and Enforcement, Audit Report No. 2000-P-10, U.S. Environmental Protection Agency, Office of Inspector General, March 20, 2000. Available online at http://www.epa.gov/oigearth/ereading_room/list300/00P0010.pdf

6. Ibid.

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