Abstract: 6640 A. Introduction
1. Sources and Significance
Agricultural chemicals used for weed control can be found as contaminants in various aquatic systems.1 Although formerly only 2 chlorinated phenoxy acid herbicides have been among the substances regulated by the U.S. Environmental Protection Agency in drinking water, and thus were routinely measured, several other types of carboxylic acid compounds used for their toxic effects now are under regulatory control.2