Are bacteria or other pathogens present in biosolids?
Biosolids may contain bacteria or other microorganisms, depending on how the biosolids are processed. When biosolids are recycled and spread over land, any disease-causing microorganisms are exposed to a hostile environment and die. These organisms will die from factors including: exposure to ultraviolet light, exposure to heat/weather, acidity in the soil, moisture levels in the soil, or digestion from other organisms in the soil. In King County, there has never been any reported illness associated with the recycling of biosolids.
