Whole foods bans biosolids – but does it matter for food safety?

Ashley Chaifetz, a PhD student studying public policy at UNC-Chapel Hill writes,

Whole Foods announced recently that they are banning produce grown with biosolids (also  known as its less-friendly moniker, sewage sludge), which sounds pretty awesome. But it’s hard to know if the new rule makes their products safer. Biosolids are a fertilizer that comes from municipal waste. Treated human poop. Like composted animal manure, it’s seen as a way to enrich the soil.  According to the U.S. IMG_4169Environmental Protection Agency (EPA), sludge is used on less than 1% of agricultural land and promotes the growth of agricultural crops, gardens and parks.

Sewage is full of whatever it is that people consume or flush and can sometimes include pharmaceuticals and heavy metals. But the abundant fertilizer mix is treated, through what EPA says are physical, chemical and biological processes to remove contaminants and solids. The sewage is then treated with lime to lessen the smell and it is all sanitized to control pathogens.

The EPA has 2 tiers of standards regarding sludge. The National Academy of Sciences has looked at the outputs and states “the use of these materials in the production of crops for human consumption when practiced in accordance with existing federal guidelines and regulations, presents negligible risk to the consumer, to crop production and to the environment.”

According to NPR’s The Salt, even Whole Foods doesn’t think the ban changes much.

Whole Foods spokeswoman Lindsay Robison tells The Salt that biosolids were banned in the name of transparency and being consistent with the U.S. Department of Agriculture’s National Organic Program, which doesn’t allow the material on fields where any certified organic product is grown. But, she adds, the company’s new biosolids ban won’t actually impact any of the company’s growers because, as far as the company knows, none of them use the material.

Some soil folks have weighed in on the ban, suggesting that Whole Food’s approach here is more about marketing and business decisions than food safety.

This is a resource that’s really undervalued,” says Sally Brown, a soil scientist at the University of Washington who has been studying biosolids for over a decade. “If you do the carbon accounting, you see that biosolids actually capture carbon, unlike synthetic fertilizer, which is what farmers would otherwise be using.”

The opposition to biosolids comes from the fact that people are still uncomfortable with any material made from human waste, even if it’s been heavily processed and treated, Brown notes.

“People have been taught that poop is dangerous and it makes you sick, and so they’re suspicious of it,” she says. “And municipalities have done a terrible job of communicating what they do and what wastewater treatment really is.”

So where does the Whole Foods ban come in?

“Whole Foods,” says Brown, “made a business decision rather than a sustainability or environmentally based decision.”

Is it safe to use compost made from treated human waste?

During a visit to a large, international city, I was hanging out with a public health type, who pointed out some row housing visible from the building we were in, and each one seemed to have a decent-sized garden. He said those gardens supply a lot of the produce to the high-end restaurants in the city. And they all use night soil.

Human poop.

Eliza Barclay of NPR reports that any gardener will tell you that compost is “black gold,” essential to cultivating vigorous, flavorful crops (why do they write with dick night.soilfingers?).

Barclay was excited the U.S. Composting Council was connecting community gardeners with free material from local facilities through its Million Tomato Compost Campaign.

I signed us up last month, and was promptly contacted by Clara Mills, the environmental coordinator for Spotsylvania County in central Virginia. Mills volunteered to deliver a dump truck full of compost to our garden from her facility, an hour away. It sounded too good to be true. Then one of my fellow gardeners noticed the source of the Spotsylvania compost: biosolids, or human poop that’s been treated and transformed into organic fertilizer.

About 50 percent of the biosolids produced in the U.S. are returned to farmland through a process that is heavily regulated by the Environmental Protection Agency. Even so, some people – including the Sierra Club — remain skeptical of the use of this waste product in food production. They worry that heavy metals, pathogens or pharmaceuticals might survive the treatment process and contaminate crops. So what’s an urban gardener to do in light of mixed perceptions about whether it’s OK to use poop to grow your food?

First, remember that for thousands of years, before the invention of synthetic fertilizer in 1913, many farmers utilized their decomposed sewage, sometimes called “night soil,” to replenish the soil with nutrients lost in farming. The Chinese were especially adept at using human waste this way – one historical account notes that in 1908, a contractor paid the city of Shanghai $31,000 in gold for the privilege of collecting 78,000 tons of human waste and carting it off to spread on fields.

When growing cities required that sewage be piped outside of the city, the practice dropped off and attention turned to improve wastewater treatment to avoid polluting waterways. Raw waste is, of course, nasty stuff, and only useful after all the dangerous bacteria have been killed off, either by heat or anaerobic digestion.

But the sludge was still piling up in landfills, so scientists began testing how to use it in agriculture safely; the waste was a free source of nutrients like nitrogen and phosphorus, afterall. And letting it sit in landfills or incinerating it created its own night-soil-collector-on-way-to-work-armed-with-long-spade-and-basketsenvironmental issues. By the 1990s, the Environmental Protection Agency created strict standards with two tiers for biosolids still in use today. To sell Class A biosolids to farmers and gardeners, facilities have to ensure that there are no dangerous heavy metals or bacteria in the end product.

The ick factor, however, has not faded entirely.

Bowing to public feedback, the U.S. Department of Agriculture decided in 2000 to prohibit the use of sludge in the National Organic Program. This was in spite of the fact that “there is no current scientific evidence that use of sewage sludge in the production of foods presents unacceptable risks to the environment or human health,” USDA spokesman Samuel Jones tells The Salt.

A handful of activists have also sounded the alarm on the widespread use of biosolids in conventional agriculture. They allege, among other things, that the EPA-approved treatment of biosolids doesn’t address all the possible contaminants in the waste.

Maybe, but I’d rather have poop treated using science than some backyard night soil.