Do we really know what’s in biosolids?
Environmental scientists know a lot about what’s in biosolids and are learning more each year. EPA conducted extensive risk analysis of the possible pollutants in biosolids when it established safe limits for land application of biosolids. Under federal and state regulations, each wastewater treatment plant must test the flow entering the wastewater plant to ensure it meets strict pretreatment limits. Biosolids resulting from wastewater treatment must also be tested to meet EPA standards. Biosolids do contain trace amounts of pollutants, which if they occurred in high concentrations, would be considered a human or environmental danger. But this is true also for compounds found in our water, air and food. The presence of these compounds in these minute quantities does not represent a risk to human health or the environment.
