The Lake Superior Research Institute (LSRI), contracted with Blasland, Bouck & Lee, Inc. to measure
lead concentrations in samples from seventeen sites and to evaluate the toxicity of sediment
samples from ten of these sites toward the benthic invertebrates, Chironomus tentans and Hyalel/a
azteca. In addition, a test of the bioaccumulation of lead from sediment at ten sites was performed
with the benthic invertebrate, Lumbriculus variegatus. This test was preceded by a four-day
toxicity test of four of the sediments covering the range of measured lead concentrations in the
samples.Blasland, Bouck & Lee, Inc