Herman R. Feltz Marvin L. Yates Hans J. Crump-Wiesner 1973 <p>Data gathered from monitoring activities and project&nbsp;studies indicate the ubiquitous occurrence and distribution of polychlorinated&nbsp;biphenyls in the aquatic environment. Residues have been&nbsp;detected in samples from 19 States, representing nearly every region of&nbsp;the country. Concentrations ranged from 0.1 to 4.0 ug/l in unfiltered&nbsp;water samples and 5.0 to 3,200 ug/kg in bottom sediments. PCB&nbsp;residues were also found in fish and aquatic plants. Samples were&nbsp;prepared by the same techniques used for general chlorinated insecticide&nbsp;detection, with special attention to cleanup and separation of&nbsp;PCB's from other compounds. Basic identification and quantification&nbsp;were made by dual-column electron-capture gas chromatography and&nbsp;confirmed by gas chromatography mass spectrometry whenever possible.&nbsp;The sampling program is expected to be broadened geographically&nbsp;in 1973 and increased in successive years in order to more adequately&nbsp;define the distribution of PCB residues in the major drainage basins of&nbsp;the United States.</p> application/pdf en U.S. Geological Survey A study of the distribution of the polychlorinated biphenyls in the aquatic environment article