Adult aquatic insects as biomonitors of organochlorine contamination in freshwater habitats.

摘要

The bottom-dwelling larvae of aquatic insects are useful indicators of organochlorine (OC) contamination in aquatic habitats. However, these animals are often difficult to collect in numbers sufficient for contaminant analysis by gas chromatography. Winged, night-active adults retain accumulated contaminants, and can be collected in large numbers using light traps. Methodology was developed and evaluated for collection and analysis of adult caddisflies (Trichoptera) and mayflies (Ephemeroptera) for monitoring OC contaminant levels in freshwater habitats. Insects were collected using light traps from Great Lakes connecting channels and reference sites, and samples were analyzed for contaminants. Contaminant concentrations in samples of adult insects broadly corresponded to reported levels of chlorinated organic contaminants in sediments of the rivers and lakes of their origin. Spatial pattern of contaminants among insect samples collected along the length of rivers reflected the pattern documented for sediments in all Great Lakes connecting channels. Contaminant concentrations in insects varied with time in the Detroit and St. Clair rivers. Significant differences in contaminant concentration were found in animals of different species from the same location. Light-trapped adult aquatic insects are well suited for use in long-term biomonitoring programs, and for preliminary or synoptic studies of aquatic contamination in previously unsurveyed areas. (Abstract shortened by UMI.) Source: Masters Abstracts International, Volume: 30-03, page: 0638. Chairman: J. J. H. Ciborowski. Thesis (M.Sc.)--University of Windsor (Canada), 1990.