A study by U.S. Department of Agriculture (USDA) scientists and cooperators provides new details about how fertilizing soils with biosolids also introduces triclosan—an antibacterial agent in soaps and other cleaning supplies—into the environment. Farmers add “Class B” biosolids, also known as treated wastewater solids, to their fields as a fertilizer. These biosolids meet federal regulations for human health and safety, but little information has been obtained about their triclosan levels. Triclosan has not been identified as a human health hazard, but the U.S. Food and Drug Administration is currently conducting a scientific and regulatory review of the compound.
For this project, Agricultural Research Service (ARS) chemist Clifford Rice, in the ARS Environmental Management and Byproducts Utilization Laboratory in Beltsville, Md., partnered with University of Maryland engineers Nuria Lozano and Alba Torrents. District of Columbia Water and Sewer Authority scientist Mark Ramirez also contributed to the study. ARS is USDA’s principal intramural scientific research agency.