Systematic monitoring of potential endocrine disrupting organic contaminants in northern and southern Missouri streams

ENVR 171

Paul Nam, nam@mst.edu1, Chih-chin Liu, huangy@mst.edu2, Mauricio E. Solis2, Yue-wern Huang2, and Dev K. Niyogi, niyogid@mst.edu2. (1) Department of Chemistry, Missouri University of Science & Technology, 1870 Miner Circle, 142 Schrenk Hall, Rolla, MO 65409, (2) Department of Biological Science, Missouri University of Science & Technology, 1870 Miner Circle, 105 Schrenk Hall, Rolla, MO 65409
We have conducted a comprehensive 4-year study of potential endocrine-disrupting organic chemical levels in four northern and southern Missouri streams that received runoff from confined hogs, pastured cattle and row crops. From each location, monthly collection of 24-hour composite water samples were analyzed using solid phase extraction (SPE) and gas chromatography-mass spectrometry (GC-MS) methods for the identification and quantification of target organic contaminants. Most commonly detected chemicals were metolachlor, atrazine, nonylphenol, bisphenol-A, alkyl phthalates, etc. There was a direct relationship between the observed water pollution by pesticide/herbicide chemicals and the agricultural practices of the area, as regards to seasonal application.