RESUMO
Toxicity and uptake data for Limnodrilus hoffmeisteri generated by nickel in systems using three natural sediments (trout farms: El Oyamel, El Truchón, and El Potrero), are presented. Nickel uptake and hemoglobin concentration were studied in L. hoffmeisteri exposed to spiked sediments. Nickel concentration and its toxic effect on hemoglobin were used as indicators of exposure. Sediment texture was also considered. Hemoglobin concentration decreased after treatment with nickel. The hemoglobin concentration test indicated a response to the bioavailability of nickel. This investigation clearly documents that sediments of El Truchón, El Oyamel, and El Potrero exhibit a toxicity potential. These results suggest the usefulness of diversity of bioassays for evaluating the toxicity of sediments polluted with heavy metals.