| A new Washington Post piece by Darryl Fears claims sewage sludge is safe enough to put in your mouth. Specifically, the statement was made about "Class A Biosolids," the treated sewage sludge (renamed "biosolids" to make it sound less unpleasant) that has regulated amounts of 10 heavy metals, salmonella, and fecal coliform.
What else might you find in sewage sludge? Well... Alkylphenols and alkylphenol ethoxylates, dioxins and furans, flame retardants, heavy metals (including some that are not regulated), hormones, pesticides, perfluorinated compounds, pharmaceuticals, phthalates, polycyclic aromatic hydrogens, steroids, and more... Still wanna put that in your mouth?
Fears was not advocating that anyone put sewage sludge in their mouths... at least, not directly. The article was instead about how sludge should be used as fertilizer for food crops... which people would then put in their mouths.
For the past year, on and off, I've been working with the Center for Media & Democracy's Food Rights Network, a group that opposes the use of sewage sludge as fertilizer on food crops. So, full disclosure, I've been getting paid to research the hell out of sewage sludge and to write about it. I've even been paid to go to my local Home Depot and buy three bags of sludge compost to send samples to a lab for testing. And let me tell you... if the long list of sludge contaminants and the EPA's own record of what they found in sewage sludge doesn't scare you off of using sludge as fertilizer, the smell of it will. It's not a poop smell - it's a chemical smell. An incredibly volatile, potent one.
The question is, of course, what are you putting in your mouth when you eat food grown in sludge? And the answers are: "We don't know" and "That depends." We don't know because it's almost entirely unregulated and because there are an awful lot of chemicals out there that just haven't been studied well enough to have the answers. Additionally, once you finish studying each individual chemical, then you'd have to study all of the combinations to see what happens when you mix them together in a toxic goop and apply them to farms and gardens. And it depends because each batch of sewage sludge is different, based on which households, hospitals, and industries are contributing to the waste stream and what they've put down the drain that particular day or week.
For farmer Andy McElmurray, it depended that a Nutrasweet plant was dumping thallium (rat poison) - an unregulated contaminant in sewage sludge - into the waste stream. The thallium went from the sludge applied to his soil, to his forage crops, to his cows, and all the way to the milk he sold to grocery stores. He only found out about the hazards of sludge after an extensive investigation into why his cows were dropping dead one after the other. McElmurray and his dad both got sick from working around sludge, and the farm went out of business. Dairying isn't very profitable when your cows are all dead.
Fears notes the sludge industry's favorite talking point: We have all of this human waste, and what are we going to do with it? Well, what should we do with pesticides, perfluorinated compounds, and flame retardants? I don't know. I don't think there's a good answer. In the case of some of the most common flame retardants (PBDEs), the world's answer was to ban them in the Stockholm Convention on Persistent Organic Pollutants. I think that's a step in the right direction. The problem is that "persistent" refers to the fact that this stuff doesn't break down. The answers to the sludge problem are upstream ones. We shouldn't make such toxic substances if we don't have a way to dispose of them. So, sure, it's a problem to figure out where to put all of the sewage sludge. But lying that it's safe and then selling it to unsuspecting gardeners ain't the answer.
Another favorite sludge talking point in the article is that manure, including human poop, is "the world's original fertilizer." And, sure, the Chinese were famous for using night soil as fertilizer (one reason why you don't see salads on the menu at Chinese restaurants... all the veggies are cooked in Chinese cuisine). But the pre-industrial Chinese were not manufacturing and mixing toxic chemicals in with their night soil.
So go ahead, Darryl Fears, put some class A biosolids in your mouth. Or, let's make it more pleasant... how about a carrot grown in them? Still wanna eat that?