The Alliance For A Clean Environment
By John Tuohy, USA TODAY - July 13, 2000
An upcoming report by the Centers for Disease Control and Prevention concludes that sewage sludge that has been converted to fertilizer can pose a potential health risk from E. coli, salmonella, hepatitis B and other bacteria and viruses. Workers who handle sludge are especially at risk, scientists found.
Sludge is made from human waste that is flushed down toilets in homes, businesses and industry. Following guidelines set by the federal Environmental Protection Agency, municipal sewer plants treat the waste to remove toxic metals and kill diseases, then ship the sludge to farmers and landowners to use as a nutrient to grow crops and plants.
Since the EPA approved the sludge program in 1993, millions of tons have been spread on land across the country, including the White House lawn.
EPA rules divide sludge - which it calls biosolids - into two categories, depending on how it is treated and cleaned. The more expensive Class A treatment kills all the pathogens that live in the waste. The more common Class B treatment kills most, but not all, the pathogens.
The CDC is now recommending that all sludge be cleaned to Class A standards because of the risk that diseases could be transmitted through the Class B sludge. "The best control is to eliminate the hazard by treating the biosolids to the Class A pathogen-free levels before application," writes Joe Cocalis, a scientist with the CDC's National Institute for Occupational Safety and Health (NIOSH), in a late draft he wrote with scientist Nancy Burton.
The report is to be released soon and is awaiting only the signature of the NIOSH director.
It's the first time the EPA's sludge program has been so closely scrutinized by another government health agency, and it comes on the heels of two other investigations that found problems with the sludge program. Reports by the EPA's inspector general and Cornell University in Ithaca, N.Y., both found that sludge could be harmful to the public. The CDC report also bolsters the claims of a scattered conglomerate of environmentalists and citizens who say sludge is harmful to people and the ecosystem. They include two mothers in the Northeast who blame sludge for the deaths of their sons. People who live near sludge claim it has made them sick. And farmers contend it has killed their livestock.
Sludge has become the preferred method of waste disposal for the nation's 16,000 municipal sewage plants because it is much cheaper than the alternatives - incineration and land filling. In fact, in most cases, tons of sludge are given away free to farmers, and the EPA has successfully promoted sludge as an environmentally friendly way to recycle sewage.
About 60% of all sludge is now used as fertilizer, and farmers who use it say it beats anything on the market.
But the CDC suggests that workers who handle Class B sludge wear protective clothing, including respirators, goggles, coveralls and gloves. Scientists made their conclusions after investigating complaints of sickness by five workers at the Lesourdesville facility of the Butler County (Ohio) Department of Environmental Services.
"Based on available scientific evidence, we are developing recommendations for preventing potential risks to workers in settings where exposure to Class B biosolids may occur," NIOSH spokesman Fred Blasser said in a statement.
Officials with the EPA insist Class B sludge is perfectly safe when used correctly and say that there is no scientific evidence that it isn't.
"If we were to require Class A sludge, we would need the data to show us it is necessary to protect public health, and that data is not out there," says Diane Regas, deputy assistant administrator for water at the EPA. "We wouldn't want to impose new rules on the cities without the data. "
However, she calls the worker recommendations "very useful" and "common-sense advice."
Sludge critics say the CDC recommendations have much larger implications. If the CDC is recommending that workers shield themselves against sludge, they say, then the EPA should make sure the public is protected from sludge, too. NIOSH can only recommend changes in the workplace; the EPA can initiate public health policies.
"In the history of public health, I can't think of an instance when the workplace requirements were stricter than they were for the public," says EPA microbiologist David Lewis, who is suing the agency because he claims it is trying to fire him for criticizing the sludge program. After all, Lewis says, any person can walk right onto a farm laden with tons of sludge and be as close to it as any worker.
That's what Brenda Robertson of Osceola Mills, Pa., says happened to her 11-year-old son, Tony Behun, in October 1994.
Tony rode his motorbike through a hillside at the site of an old strip mine that was covered in sludge, which plastered him from head to toe. The next day, he got sick. Within a week, he was dead.
For the past year, since Robertson began to suspect sludge may have been the cause, she has been battling the Pennsylvania Department of Environmental Protection, which insists that sludge played no part. She has lobbied at the capital in Harrisburg and written Gov. Tom Ridge for support.
"I don't think the EPA wants to admit there needs to be changes made," Robertson says.
In Greenland, N.H., Joanne Marshall is suing to reach closure for the death of her son, Shayne Conner, in 1994, when he was 26. Marshall lived downwind of a sludge site, and she claims the ammonia fumes that her son inhaled caused his death. She is suing the sewage plant that treated the sludge, the waste hauler who transported it and the farmer who grew his crops with it. "I am 100% certain his death was caused by sludge," she says. "I have been disappointed and dismayed with the response of the government."
Rufus Chaney, a research agronomist with the U.S. Department of Agriculture, calls claims like Marshall's "ludicrous."
"Even if there were enough ammonia to make someone sick, the dispersal you would get on a big field negates it," Chaney says.
Other studies critical
The CDC is only the latest critic of sludge:
In March, an audit by the EPA's inspector general concluded that "EPA cannot assure the public that current land application practices are protective of human health and the environment." The study found that biosolids "may result in increased risks to the environment and human health." The EPA reviewed only 38% of the reports sent to it by waste treatment plants, performs few inspections of the plants and does not keep track of the cumulative amount of pollutants at sites where sludge is spread, and there "is virtually no oversight" of the program, auditors found. The EPA's Regas says the states are supposed to self-regulate because the EPA doesn't have the manpower to inspect every site in the country.
In 1999, a study by Cornell University's Waste Management Institute said the EPA's rules on sludge "do not appear adequately protective of human health." The study found that groundwater leaching of sludge might be dangerous. Ellen Z. Harrison, director of the institute, says the EPA tried to discredit the report rather than address the concerns raised.
The House Science Committee held hearings in March to examine allegations that top EPA administrators intimidated local activists who opposed sludge in their towns.
A handful of scientists within the EPA, led by Lewis, are openly challenging the EPA's sludge rules.
Some scientists say pathogens that survive after Class B treatment are resilient enough to live long after Class B biosolids are spread on fields. They say the EPA never did thorough testing that could prove otherwise.
"They developed a theory that was not biologically sound," Lewis says. "I think that in some cases you can find E. coli or other pathogens living months or years later."
Al Gray, executive director of the Water Environment Federation, a non-profit group of sewage plant scientists and engineers, says sludge opponents don't have the science to back up their fears. "We have yet to have a documented case of a worker or citizen getting sick from biosolids," he says.
Nevertheless, some rural local governments have told their leaders they don't want sludge from sewage plants in New York and Los Angeles dumped in their towns.
In New Hampshire, 44 municipalities have banned or restricted sludge. In California, 16 counties have used local government action to keep the sludge away.
But there are still a great number of farmers who swear by sludge.
In Cottage Grove, Minn., farmer Gene Smallidge, 60, says sludge is helping him "get some of the highest corn yields in the state on some of the worst land."
"If you believe in recycling, then this is the ultimate," Smallidge says. "Everyone creates it and everyone should learn to re-use it."
P.O. Box 3063
Stowe, PA 19464
| donate online | contents | contact us | join | contact web master |