The distribution of trace elements in dissolved and suspended phases, streambed sediment, and fish samples is described for principal streams in the lower Kansas River Basin, Kansas and Nebraska, from May 1987 through April 1990. Large median concentrations of dissolved lithium and strontium in the Kansas River were related to saline ground-water discharge, and large median concentrations of dissolved strontium in Mill Creek near Paxico, Kansas were related to Permian limestone and shale. Large concentrations of arsenic, chromium, and lead in water were identified downstream from three reservoirs, which may be attributed to resuspension of bed sediment in turbulent flow near the dams or release of water from near the bottom of the reservoirs. Trace elements in streambed sediments greater than background concentrations were identified downstream from the Aurora, Nebraska, wastewater-treatment plant, from industrial or urban areas near Kansas City, Kansas, and from the dam at Perry Lake, Kansas. Median and 90th-percentile concentrations of mercury in fish-tissue samples approximately doubled from 1979-86 to 1987-90. However, concentrations in samples collected during the latter period were less than the National Academy of Sciences and National Academy of Engineering 1972 criterion of 500 micrograms per kilogram for mercury in fish tissue.
