Trace Organic Chemicals in Biosolids-Amended Soils

The presence of trace organic chemicals (TOrCs) in municipal biosolids in the U.S. has received considerable attention by the public and scientific community over the last several years. Of particular concern is whether the presence of TOrCs in biosolids results in significant risks to public health and the environment upon land application of the biosolids. While the U.S. Environmental Protection Agency has evaluated the risks associated with dioxins present in biosolids-amended soils, to date, no other TOrCs, particularly those of emerging concern, have been subjected to complete risk assessments with respect to the land application of municipal biosolids. This study identified the scientific data gaps that should be filled if appropriate risk assessments are to be conducted. The focus of this effort was to compile data from published peer-reviewed literature that addresses the occurrence, mobility, persistence, bioaccumulation, toxicity, and microbial impacts of biosolids-borne TOrCs in soils. In addition, an evaluation of the current modeling approaches employed to evaluate the risks of biosolids-borne TOrCs was conducted.