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Sludge, a free fertilizer for farmers, can pose health and environmental risks



Dotting the verdant 400 acres of pasture at Braeburn Farm, on the outskirts of Snow Camp, are New Zealand Red Devon cattle and warmblood dressage horses like Thoroughbreds and Hanoverians. The farm is divided into 27 pastures where cattle graze every day. Rotating the cattle among the pastures allows the grass to grow and minimizes the need for spraying the fields with chemically loaded fertilizers.

Dr. Charles Sydnor, now a neuro-ophthalmologist, founded Braeburn Farm in 1975, fulfilling his dream of becoming a part-time rancher with his wife, Cindy, who began training horses and teaching riding lessons. Over the past 35 years Sydnor's farm has become one of the Triangle's leaders in the national locavore movement with its grass-fed beef, pasture pork, lamb and goats.

But Sydnor did not always use conservation principles and pasture rotations to preserve his farm's integrity. Before he did a total remake of Braeburn Farm 10 years ago, Sydnor, like many North Carolina farmers, was using sludge, also known as biosolids, on his farm.

For 30 years, sludge has been applied to farmland throughout the U.S. to fertilize fields that grow food for livestock and, in some cases, humans. Yet it's only in the last decade that sludge has garnered attention from citizens, scientists and the FDA because of the uncertainty of its contents.

Sludge isn't just a byproduct of waste that creates optimal fertilizer; it can contain heavy metals, bacteria like staphylococcus (the cause of staph infection) and thousands of chemicals yet to be tested for safety by the FDA.

Sludge begins as human waste, manufacturing chemicals, landfill runoff—essentially, anything that flows down a drain, which makes knowing its contents nearly impossible. Sludge infiltrates the food chain through livestock that ingest sludge while grazing on sludge-applied fields or eating food grown in those fields. Sludge comes full circle when people eat the crops grown in the field, consume the meat or drink the milk of animals that directly or indirectly ingested the sludge. It can also enter waterways used for drinking water or irrigation.

In the Triangle, thousands of acres of farmland are spread with sludge generated from wastewater treatment plants and then hauled and applied by Houston-based Synagro Technologies, Inc., the largest recyclery of waste in the United States and a company with a problematic environmental record. While there are federal and state rules governing sludge, there is little enforcement or monitoring of the practice. And local governments have no voice in regulating the sludge that is sprayed on fields in their jurisdictions.

In the early '90s, the National Federation of Wastewater Treatment Plant Operators held a marketing contest to find a new, more appealing name for sewage sludge. From 250 suggestions, "biosolids" was chosen, but frankly, sewage sludge is largely shit. Manure. Dung. Guano. You can change the name, but it still smells the same.

If sludge were only manure, it would be less alarming. But sludge can contain thousands of chemicals, including arsenic, lead and mercury; parasites, radioactive material (found in urine from patients receiving chemotherapy) and microbes that cause diseases such as hepatitis A and food poisoning—even after the sludge has been treated at the wastewater treatment plant—according to the American Society of Civil Engineers.

Sludge can include triclosan, an antibacterial chemical found in many soaps, toothpaste, mouthwash, toys and plastic kitchenware. Because triclosan been linked to "superbugs," immune deficiencies, birth defects and other health problems, the FDA in April announced it's investigating the chemical's safety. (Many European countries and Canada have banned it from supermarkets and in materials that touch food.)

The waste heads to a municipal wastewater treatment plant, which could receive materials from sources as varied as factories, schools, hospitals, laboratories and funeral homes, as well as runoff from landfills, septic systems and storm drains.

Solids and wastewater are separated. Liquid leftovers are recycled. Solids remain on the bottom of the treatment tank. Sludge is what can't be recycled any further.

Wastewater treatment plants are required to analyze sludge according to regulatory requirements before giving it to farmers. However, testing involves looking for just a handful of chemicals, some toxic metals, levels of nitrogen, phosphorus and potassium, and coliform bacteria, which can indicate the presence of other pathogens in the waste.

"Nothing specific, like MRSA or any other specific diseases that could be present," says Sue Dayton, N.C. Healthy Communities director for Blue Ridge Environmental Defense League (BREDL).

Contaminants in sludge, particularly triclosan, can survive treatment at the wastewater plant and end up in farmland sludge. Recent studies by John Hopkins University researchers estimate that more than 100,000 pounds of triclosan are spread on farmland each year. When exposed to sunlight, triclosan is converted into dioxin, which, at high levels of exposure, can cause cancer, and at low levels, a range of serious health problems.

Despite the uncertainty of sludge's contents, municipalities have to find some method of disposing of it. They give it away to farmers, who, already cash-strapped, can use it as free fertilizer instead of expensive commercial products.

"No one really knows what is in any particular batch of sludge/ biosolids," said Dr. Jeffrey White, associate professor at N.C. State University's Department of Soil Science. "The list of potential pollutants and pathogens in sludge is a long one, and currently there are no regulatory standards and associated analytical requirements for many of them. The same is true of drinking water, although the regulatory standards for drinking water are much stricter than those for biosolids."

Sam Groce, Chatham County's livestock agent with the N.C. Cooperative Extension Service, acknowledges he is concerned about biosolids containing heavy metals, but says he is more worried about Chatham farmers who can't afford fertilizers and lime.

"It is a viable fertilizing source," Groce says. "I've heard all this debate that's going on, and it's making the farmers out to be the bad guys. Who's generating these biosolids? People who live in town."

In the '90s, Sydnor was approached by Synagro about using sludge/ biosolids on his farm. He agreed to try it.

"When you look at fertilizer you are basically looking at the nitrogen, phosphate and potassium levels," he says. "The reason any farmer will go to biosolids is that one of the most expensive components of fertilizer is phosphate, and biosolids are very high in phosphate."

Although he saved money on fertilizer, after a few years Sydnor grew concerned. "I noticed areas of grass that wouldn't do well, and the stench was awful; if you went near it your eyes would burn."

Sydnor called Synagro, which had supplied the sludge, and asked for someone to visit his farm. "Their representative just could not answer my questions about what was in it, and as a physician I had some questions about pesticides and pharmaceuticals," Sydnor says. " I realized they didn't know what was in the biosolids."

According to Jean Creech, Synagro's North Carolina technical services manager and spokesperson, the company explains the composition of biosolids to farmers before they receive material.

"Biosolids are typically about 70 percent organic matter and provide two of the three primary nutrients that plants need to grow —nitrogen and phosphorus," Creech says.

When pressed about the term "organic" matter, Creech explains, "When I used the term 'organic' I was saying that biosolids are 'of, relating to or derived from living organisms.' This is the traditional definition of 'organic.' It is an accurate description of the biosolids."

Dayton notes that it is misleading to say "biosolids is organic, because many people believe 'organic' means 'natural' or 'toxic free.'"

Synagro has contracts with more than 600 municipal wastewater treatment plants, including those in Burlington and Durham, in 37 states. The company has a checkered environmental record nationwide. Within the last 10 years, according to EPA documents, the Maryland Department of the Environment fined the company $27,000 for violating air regulations; Pennsylvania environmental officials fined it $35,000 for sewage sludge storage and land application violations, which included failing to prevent runoff from entering nearby waterways and spreading sludge on a landowner's property without permission. In Virginia, dozens of complaints have been filed against the company over allegations of road damage, odor, groundwater issues and truck traffic.

(The company wields enormous financial and political power. According to The Michigan Citizen, a Detroit City Council member plead guilty to charges of conspiracy to commit bribery after switching her vote to grant a $1.2 billion waste disposal contract to Synagro. Coincidentally, before the vote, she received $6,000 from Synagro.)

Since Sydnor couldn't confirm what was in the sludge, he stopped using it. He says farmers should question what's in the product, "even if Synagro and the EPA tell them it's fine."

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