Metal pollution associated with a landfill: concentration in water, sediment, crayfish and fish.

Abstract

Water, sediment, crayfish (Orconectes nais) and orangespotted sunfish (Lepomis humilis) were analyzed for Pb, Cd, Al, Zn, and Cu in samples taken from four sites in the vicinity of a Lyon County, Kansas landfill. Site one was immediately above the landfill on a tributary of the Cottonwood River and site two was immediately below the landfill on the same tributary. Sites three and four were above and below, respectively, the confluence of the tributary and river. There is no evidence that the landfill is a source of metal contamination for water, crayfish or fish. Concentrations of Pb, Cd, Al, Zn and Cu in sediment were, however, significantly higher below the landfill than above. Thus the landfill appears to be a major source of these metals for the tributary below. Al levels, however, may be due to naturally occurring Al minerals in the clay fraction of the sediment. The general patterns for concentrations of metals in the various components were Ph: water, fish, crayfish < sediment; Cd, AI, Zn: water < fish < crayfish < sediment; Cu: water < fish < sediment < crayfish. Al was the only metal for which the concentration in water was significantly different among sites; it was higher at site two. Pb, Cd and Al were significantly higher in sediment at site two. Zn was higher in sediment at site two than at site one, but was not significantly different from sites three and four. Cu in sediment was different among all sites, as follows: site three> site two> site four> site one. There were no significant differences among sites for any metal levels in crayfish. Al was significantly lower in fish at site two, whereas Cu was significantly higher in fish at site one. Comparing crayfish to fish showed crayfish had significantly higher mean concentrations of Cd, AI, Zn and Cu. These differences could possibly be explained by the close association of crayfish with the sediment. Cu, however, is a necessary component of hemocyanin in crayfish, and this could account for the higher levels. Although there were no significant differences among sites for Pb, Cd, Zn and Cu in water, some sites had levels higher than Kansas Department of Health and Environment recommended maximum safe levels for water within the state.