Using national sewage sludge data for chemical ranking and prioritization

Abstract

Treated sewage sludges (SSs) or biosolids are rich in organic carbon, nutrients, and, unfortunately, chemical contaminants. Accumulation of chemicals in SS is influenced by the mass of chemical produced and released into wastewater, resistance to (bio)degradation during treatment, and the chemicals' propensity to sorb to particulates. Hence, accumulation of chemicals in SS is indicative of their persistent and bioaccumulative behavior: the two characteristics that are predominantly used for chemical prioritization. Thus, it is possible for risk assessors to use existing SS survey data to identify, rank, and prioritize persistent and bioaccumulative chemicals present in the human society. In this review, we highlight unique papers that used this concept to help prioritizing chemical contaminants in SS and the environment. We additionally showcase a simple decision flowchart and scoring algorithm for prioritizing chemicals whose presence in SS warrants further investigation.