For some, composting is one of those things we routinely tell ourselves we will start doing next month. Then there are community members who have been composting for decades. Wherever you fall in that spectrum, Derek Fry, owner of Curbside Composter, believes most people are unaware of the challenges and hazards composting at home may present.

In a perfect world, composting would be straightforward. Yard and food waste would go into a bin, we’d add whatever is needed to invigorate the process, and then end up with some nutrient-rich garden food. But even our yard waste may not be as pristine as we imagine.

“Some yard waste, like lawn clippings, have glyphosate in there, and many do not want that near their family or gardens.” As a refresher, glyphosate is an herbicide found in almost all weed-killing products. Though independent research has shown glyphosate to have negative impacts on bee populations and soil health, the EPA contends that when these products are used as directed, there is no risk to human health. Still, using these glyphosate-coated grasses in compost that will eventually be used in vegetable gardens does not sit right with everyone.

There’s also potential for other things to be in our yard waste, particularly when raking leaves. Garbage and dog waste often hide under leaves, and when this stuff breaks down, whatever was in there becomes part of the makeup of the compost. Any chemical or contaminant in the compost can then end up in food grown using that compost.

To demonstrate just how difficult it is to keep undesirable chemicals out of our compost, Derek shared a video with me from Montana PBS, Dangerous Chemicals in Compost. The video explores the use of biosolids (human waste/treated sludge) in compost. Laura Orlando, senior scientist at Just Zero, a group promoting clean, zero-waste policies, talks about the unprecedented amount of propaganda being pushed to promote the safety of biosolids.

In short, biosolids contain per- and polyfluoroalkyl substances (PFAS), chemicals we often encounter as coatings on things meant to be resistant to heat, oil, grease, stains, water, etc.—Teflon, for example. PFAS are notoriously difficult to separate from biosolids due to their hydrophobic nature, and there are a number of PFAS out there known to be harmful to humans.

Biosolids are also used in Wisconsin on large farms and in compost sold at supply stores. Derek’s main concern is educating consumers rather than going to war with the state, and he encourages others to do their own research. If a bag of compost indicates the use of biosolids, much like when choosing which groceries are right for your family, make sure you are comfortable with using that compost on whatever it is you are growing.

Kyle Jacobson is a writer/editor living in Sun Prairie.

Curbside Composter

Madison, WI