FDA's Manure Proposal: What's the Big Stink About?

Getting into the weeds on proposed rules for farming.

A tractor pulling a muck spreader through a field

If you've caught wind of the controversy around proposed laws on food safety, then you know that a lot of folks are knee-deep in talks about manure. Black gold – as farmers have been known to call it – manure makes for a brilliant fertilizer. But unless it's used correctly, it can lead to serious foodborne illnesses. So, in accordance with the 2011 Food Safety Modernization Act, the U.S. Food and Drug Administration issued a proposed rule on produce early this year to place restrictions on using manure.

That's created a stink – if you will – among organic farmers, who responded with a flurry of objections during the comment period, which closed Nov. 22. At issue is the extended length of time that farmers would have to wait before harvesting soil fertilized with manure. One of the conditions that distinguishes organic from conventional farming is the requirement to build soil with organic matter, a large chunk of which is manure, explains Laura Batcha, executive vice president of the Organic Trade Association, which represents the organic food industry in North America.

Under FDA's proposed regulations, farmers would need to wait nine months before planting crops in soil where they've applied raw manure. Current organic standards have a waiting period that ranges from three to four months, depending on whether the crop's contact with soil is direct (e.g. carrots) or indirect (e.g. apples). When it comes to composting manure, a heating process that kills bacteria, the rules would newly establish a 45-day waiting period before harvesting crops with direct soil contact. Critics call these extended waits arbitrary and argue that the delays would disrupt farmers' ability to rotate crops, which also aids in their pest control.

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"By requiring farmers to wait nine months after applying manure and 45 days after applying compost before they can plant, large tracts of land would be put out of production," Maureen Wilmot, executive director of the Santa Cruz, Calif.-based Organic Farming Research Foundation, wrote in an e-mail to U.S. News. "This will reduce the quantity of food farmers can produce, and consumers would have to pay more for organic produce." Wilmot contends that the science behind the proposal is based on "worst-case scenarios, not everyday farming practices," and organic farmers and their customers are punished as a result. "Rather than over-regulate small farmers, the FDA should weigh the very slight health risks of food being contaminated by compost against the real health benefits of producing healthy, pesticide-free food, which doesn't harm the environment."

Asked about the lengthened time frame, FDA spokeswoman Juli Ann Putnam replied with the following statement: "The majority of the research the FDA consulted showed that most intestinal pathogens of public health importance, under the most common conditions, would not survive in the soil past one year. Survival studies showed that organisms most commonly associated with fresh produce outbreaks (such as E. coli, salmonella and listeria) are unlikely to survive at detectable levels in soil past 270 days. Therefore, we tentatively concluded that a nine-month waiting period between the application of untreated biological soil amendment of animal origin and the harvest of the produce would be recommended." The FDA noted that there's no waiting period for compost used in soil that does not contact produce.

According to the FDA, there was 131 foodborne illness outbreaks associated with contaminated produce from 1996 to 2010, which caused more than 14,000 illnesses and 34 deaths.

Tracing contamination to manure – or anything, for that matter – is nearly impossible, experts say. But Putnam explains the link as follows: "Few outbreaks have been directly linked to food contacting manure-containing fertilizers; however, gastrointestinal (GI) pathogens are not generally considered environmental. Therefore, any pathogens present in the growing field had to originate from some fecal source, with any raw manure that had been applied being a significant possibility."