A comparative bioassessment of sediment toxicity in lentic and lotic ecosystems of the North American Great Lakes

Abstract The bioavailability of sediment bound contaminants in lentic (Hamilton Harbour, Lake Ontario) and lotic (Detroit River connecting Lakes St. Clair and Erie) environments were assessed by a battery of multi-trophic tests using laboratory grown organisms. Hamilton Harbour is a hyper-eutrophic and highly contaminated environment due to extensive urban and industrial growth, while the Detroit River has been implicated as a major source of contaminants to Lake Erie. An array of sites across Hamilton Harbour and the Detroit River were selected, including the mouth of the Rouge River as well as the Trenton Channel—the contaminated western arm of the Detroit River. Multi-trophic acute assays were conducted using Daphnia magna, Hyalella azteca, Diporeia hoyi, and Lumbriculus variegatus. While the tests were consistent in determining the most toxic hot spots, variability existed in the sensitivities of test organisms to discriminate among less contaminated sites. The most toxic sediment in the Detroit River...