In the News: Biosolid Pollutants

Johns Hopkins is involved in the analysis of biosolids and the assessment of the inherent health risks it may cause the public.

Biosolids are created during the wastewater treatment process. When biosolids are spread on agricultural land, they add nutrients, improve soil, and enhance moisture retention. Applying biosolids to land has economic and waste management benefits, since it saves space in landfills, recycles a waste product, and reduces demand for synthetic fertilizers.

Biosolids can also contain a variety of pollutants. Some of the main offenders: per- and polyfluoroalkyl substances, or PFAS, which are found in non-stick cookware, carpets, and food packaging; triclosan, an antimicrobial found in personal care products; and unmetabolized pharmaceuticals.

The Johns Hopkins team was granted $1.87 million dollars by the EPA to study sewage and are using toxicology to provide utilities and state with guidelines to ensure that they process and handles biosolids in the least harmful way.

Since the banning of ocean dumping in 1991, biosolids have been increasingly applied to agricultural land, forests, parks, golf courses, home gardens, and lawns.

"We know very little about the organic chemical contaminants in biosolids," Prasse says. "This information is critical to the development of strategies to understand exposure and potential public health risks."

Carsten Prasse, the team lead says that this problem goes beyond biosolids alone and we need to focus on the big picture as well. The best approach may be to try and stop some of these chemicals at the source, before they even research treatment facilities and are incorporated into biosolids.

We need to think about the chemicals we use in our households and industries that are potentially problematic, why we use them, whether we really need them and can we just take them out
— Carsten Prasse