Editorial: Toxic sludge in Illinois comes with more than the obvious stench

City slickers heading to the countryside are familiar with agricultural odors, so to speak. But many of us were still surprised to learn from Tribune reporter Michael Hawthorne this week that the origin of much of what we can smell on Illinois fields this summer is likely to be some portion of the 300 million pounds of human feces that are sent each year to U.S. treatment centers like those run by the Metropolitan Water Reclamation District of Greater Chicago.

And if that were not disconcerting enough, the Tribune also reported that such “sludge” (the stuff left behind once wastewater is treated and released) could be laced with toxic forever chemicals, otherwise known as per- and polyfluoroalkyl substances, or PFAS.

According to the Environmental Protection Agency, research has suggested that exposure to high levels of certain PFAS may lead to “adverse health outcomes,” including testicular cancer and liver damage. These chemicals have been around for a long time and show up everywhere from drinking water to food packaging to dental floss, but it is still disconcerting to discover that they might be spread in massive quantity on the fields where the food we eat is grown.

According to Tribune reporting, more than 615,000 tons of “biosolids” (to borrow the euphemism of choice) from the Metropolitan Water Reclamation District has been plowed into some 29,000 acres of Illinois farmland located near Aurora. You might be familiar with its odor.

The main problem here is that when sludge is used as fertilizer, the concentration levels of those problematic substances, present in our bodies and, of course, in industrial waste, is intensified, even though there is little or no governmental monitoring of its risks.

Spread the stuff on fields and it can bleed into wells, inside the stomachs of livestock and back into the human food chain, making a mockery of the circle of agricultural life.

Toxic sludge has its defenders, who argue it is safe, environmentally friendly and offers no worse exposure than the myriad other ways we are exposed to PFAS. And, of course, other ways of getting rid of this stuff (burning, dumping into landfills) have their costs.

But Illinois uses this kind of fertilizer in far greater quantities than most states and farmers are incentivized to make this their choice, as it can be offered to them without charge. That’s because the disposal of human waste is expensive; public authorities are happy to save money by getting rid of it in other ways.

As far back as 2014, Whole Foods said it would not sell produce grown in fields fertilized by sludge. In April this year, Maine banned “sludge generated from a municipal, commercial or industrial wastewater treatment plant” on any agricultural field within its borders. And logic certainly suggests that there is little point in removing chemicals from water if we are simply going to reinject them into the cultivation of the food we eat.

Then, of course, there is the not-inconsiderable impact of this stuff on the people who live right by all the fields fertilized in this noxious way. The practice needs a lot more attention in Springfield, especially when it is so atypically widespread in the state.

Here in Chicago, some of us might be surprised by the prevalence of this stuff. But in many agricultural communities in Illinois, they are aware of it each and every day. All they have to do is follow their noses.

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