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Urban contributions of glyphosate and its degradate AMPA to streams in the United States

January 1, 2006

Glyphosate is the most widely used herbicide in the world, being routinely applied to control weeds in both agricultural and urban settings. Microbial degradation of glyphosate produces aminomethyl phosphonic acid (AMPA). The high polarity and water-solubility of glyphosate and AMPA has, until recently, made their analysis in water samples problematic. Thus, compared to other herbicides (e.g. atrazine) there are relatively few studies on the environmental occurrence of glyphosate and AMPA. In 2002, treated effluent samples were collected from 10 wastewater treatment plants (WWTPs) to study the occurrence of glyphosate and AMPA. Stream samples were collected upstream and downstream of the 10 WWTPs. Two reference streams were also sampled. The results document the apparent contribution of WWTP effluent to stream concentrations of glyphosate and AMPA, with roughly a two-fold increase in their frequencies of detection between stream samples collected upstream and those collected downstream of the WWTPs. Thus, urban use of glyphosate contributes to glyphosate and AMPA concentrations in streams in the United States. Overall, AMPA was detected much more frequently (67.5%) compared to glyphosate (17.5%).

Publication Year 2006
Title Urban contributions of glyphosate and its degradate AMPA to streams in the United States
DOI 10.1016/j.scitotenv.2005.01.028
Authors D.W. Kolpin, E. M. Thurman, E.A. Lee, M. T. Meyer, E. T. Furlong, S.T. Glassmeyer
Publication Type Article
Publication Subtype Journal Article
Series Title Science of the Total Environment
Index ID 70031191
Record Source USGS Publications Warehouse
USGS Organization Iowa Water Science Center; Toxic Substances Hydrology Program