Sewage sludge (also known as ‘biosolids’) refers to the semi-solids left over from municipal waste water treatment. It contains highly variable mixtures of household and industrial pollutants. These include radioactive material, pharmaceuticals, organic chemicals, antibiotics, and heavy metals, excess nutrients (e.g. N and P), and human pathogens. Its safe disposal has been problematic for municipalities and EPA since the inception of modern large-scale water treatment facilities (1).
Despite its documented harmful impacts, the U.S. EPA and others vigorously promote land application of sewage sludge — to farmers and ranchers as a fertilizer and to households as organic compost.
Many scientific experts argue that the risks of land application are not adequately addressed by EPA’s current 503 sludge rule. They believe the short and long term health of the public as well as the environment are at risk. The Bioscience Resource Project has just added Sewage Sludge (Biosolids) — land application, health risks, and regulatory failure to its resource pages. This page summarizes and links to key scientific papers that provide an overview of the current health, environmental, and political issues around land application of sludges. Included are suggestions for reformulating the problem to ensure clean water without toxic sludge production.
To access the new page see: Sewage Sludge (Biosolids) — land application, health risks, and regulatory failure.
(1) For an illuminating non-technical introduction to the origins of sewerage systems and the creation and disposal of toxic sludge see: Civilization & Sludge: Notes on the History of the Management of Human Excreta by Abby A. Rockefeller.