Metals, boron, and selenium in Neosho Madtom habitats in the Neosho River in Kansas, U.S.A

In 1991 and 1992 we determined the levels of metals, arsenic, boron, and selenium in the Neosho River drainage in southeastern Kansas, the primary habitat for the threatened Neosho madtom (Noturus placidus). We evaluated concentrations in sediments, mussels (Quadrula pustulosa and Q. metanevra), and fish (Percina phoxocephala, Cyprinus carpio, and Ictiobus bubalus) from three sites on the Neosho River and one site on the Cottonwood River. We also evaluated contaminant concentrations in C. carpio composite samples collected by the Kansas Department of Health and Environment (KDHE) at two additional locations on the Neosho River in 1990-92. Sediments were contaminated by lead. Concentrations of selenium, boron, and most metals in mussels were low to normal for biota. Arsenic levels in mussels and fish suggest low-level contamination of biota. Aluminum, barium, manganese and strontium concentrations were much higher in mussels than in fish. Five fish composite samples had cadmium concentrations that indicate chronic deleterious effects on biota. Lead concentrations in six fish samples were elevated. Mercury concentrations in most large fish composites exceeded concentration for protection of animals that might consume them. We believe that reductions in cadmium, lead, and mercury contamination, in particular, would benefit aquatic life in the river.