A reconnaissance study of halogenated organic compounds in catfish from the lower Mississippi river and its major tributaries

Blue catfish, ( ictarurus furcatus ), black bullhead catfish, ( ictalurus melas ) , channel catfish ( ictalurus punctatus ) , and flathead catfish ( pylodictus olivaris ) , were collected along a 1200 mile river reach of the Mississippi River and its major tributaries. Tissue samples were extracted and analyzed by fused silica capillary gas chromatography/mass spectrometry (GC/MS) to determine the concentrations of hydrophobic organic halogenated contaminants that have bioconcentrated within the tissues. The compounds identified in the tissue include chlordane, polychlorinated biphenyls (PCBs), DDT and its metabolites along with several other chlorinated pesticides. The data indicates that the southern reach of the river system appears to be more contaminated than the middle and upper reaches of the study area.