Sewage Sludge Surveys

Surveys of Pollutants in Sewage Sludge / Biosolids

It is important to characterize and understand what chemicals may be present in sewage sludge and biosolids that are generated by the nation's publicly owned treatment works. EPA has conducted three national sewage sludge surveys since 1988 to obtain unbiased national estimates of the concentrations of more than 500 pollutants in sewage sludge, including metals; dioxins and dioxin-like compounds; inorganic ions; certain organics (e.g., polycyclic aromatic hydrocarbons, semivolatiles); polybrominated diphenyl ethers (flame retardants); and pharmaceuticals, steroids and hormones in sewage sludge managed by land application.

The most recent survey, the Targeted National Sewage Sludge Survey, is a valuable step in advancing the understanding of what is present in treated sewage sludge and in evaluating what potential harm those pollutants may pose to human health and the environment. It also fulfills an important commitment under the agency's priority focus areas for pharmaceuticals and personal care products (PPCPs) by providing the first national estimates of which compounds may be present in sewage sludge and at what concentrations.

Separate from EPA, in October 2000 the Association of Metropolitan Sewerage Agencies (AMSA), now known as the National Association of Clean Water Agencies (NACWA), also conducted a voluntary survey (AMSA Dioxins Sewage Sludge Survey, see report below) to determine current levels of dioxin-like compounds (i.e., polychlorinated dibenzo-p-dioxins, polychlorinated dibenzofurans and dioxin-like coplanar PCBs) in biosolids (sewage sludge). These data were collected to assist U.S. EPA in developing an environmentally sound and technically correct dioxin decision for land-applied biosolids.

Survey documents are provided. If you have trouble accessing any content in the following documents, please contact Rick Stevens by phone (202-566-1135) or email (

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