Written by Andy Bajorat, CHMM, who works in BBJ Group's Chicago OfficeRecently, there have been a number of news stories about per- and polyfluoroalkyl substances (PFAS) entering the food supply through contaminated biosolids. The most recent example pertains to the town of Lapeer, Michigan, which had been providing biosolids from its municipal wastewater treatment facility to local farmers until it was discovered that the material contained PFAS. Although Michigan has received a great deal of PFAS-related attention, it’s not the only state where PFAS compounds are found in biosolids. In recent weeks, these compounds have been found in biosolids in Alabama, Maine, New Hampshire and Wisconsin.
Below, we focus on the following: What are biosolids? How did this material come to be impacted with PFAS? And what kinds of companies should be concerned?
What are biosolids?
Biosolids are the solid material that remains after sewage is chemically and biologically treated at a wastewater treatment facility. Land-applying biosolids has a number of benefits compared to other disposal options.
- Biosolids are rich in nutrients and organic material, making it a great fertilizer. As a result, land application of biosolids is a common practice nationally. Treatment plants commonly donate clean biosolids to farmers, which provide them with something valuable for their crops while reducing the amount of chemical fertilizers needed for agriculture. For similar reasons, biosolids are also distributed for use in home lawns and gardens.
- Landfilling is expensive, and sending biosolids to a landfill takes up valuable capacity in that landfill.
- Incinerating is also expensive and results in undesirable air emissions and permitting related to those emissions. Ash from the incineration must also be landfilled, which results in additional expense.
Note that, while incineration and landfilling biosolids are undesireable outcomes, doing such becomes necessary if the biosolids are contaminated and, therefore, unsuitable for land application.
How do PFAS compounds get into biosolids?
PFAS compounds (such as perfluorooctanoic acid [PFOA) and perfluorooctane sulfonate [PFOS]) are generally resistant to microbial degradation and oxidation, such as that which occurs during wastewater treatment. Consequently, if PFAS-containing industrial wastewater is discharged to the municipal wastewater treatment system, those compounds can end up in the biosolids. This is what happened in Lapeer, Michigan. Specifically, according to the Michigan Department of Environmental, Great Lakes and Energy (EGLE), a PFOS-containing mist suppressant was used by a plating company in an effort to control air emissions related to their chromium electroplating process. Typical wastewater treatment processes do not control PFAS compounds and, consequently, PFOS-containing wastewater was discharged to the municipal treatment plant.
How can this affect BBJ Clients?
Food Manufacturers and Processors
According to U.S. Environmental Protection Agency (USEPA), two PFAS compounds, PFOA and PFOS, are associated with increased cancer risk and damage to liver and the thyroid. Plants can uptake these PFAS compounds if crops are grown in PFAS-impacted soils, irrigated with PFAS-impacted water, or if their roots extend into contaminated groundwater. At a minimum, lettuce, tomatoes and radishes are believed to uptake PFAS.
These effects on the food supply are not simply theoretical; FDA has identified PFAS compounds in meats, dairy products, seafood and baked products sold in grocery stores. Consequently, food manufacturing and processing companies may want to consider whether biosolids have been applied to fields that source their ingredients.
Investors may not be expecting to encounter environmental problems when selecting farmland sites for development. However, given the prevalence of biosolid application at agricultural properties, PFAS-related risks should be considered during due diligence.