RELEVANCE AND APPLICABILITY OF A SIMPLE EARTHWORM BIOMARKER OF COPPEREXPOSURE .1. LINKS TO ECOLOGICAL EFFECTS IN A LABORATORY STUDY WITH EISENIA-ANDREI

A simple earthworm biomarker, neutral-red retention by coelomocyte lys osomes, was measured concurrently with ecological parameters in order to link effects at different levels of biological organization in a la boratory study, Exposure of the earthworm Eisenia andrei to an increas ing range of soil copper concentrations in the laboratory indicated a threshold range for the neutral-red assay at soil copper concentration s between 40 and 80 mg Cu kg(-1). This threshold coincided with the so il to worm copper bioconcentration factor decreasing from 1 to 0.3 and thus an apparent onset of a copper regulatory mechanism, Effects at t he individual and population levels only occurred at soil copper conce ntrations beyond that of the biomarker threshold. Thus, it was possibl e to differentiate between exposure and toxicity, It was therefore pos sible to conclude that the neutral-red assay has great potential and r elevance in earthworm ecotoxicity studies, The assay provides an early warning that can be linked directly to important physiological change s that were observed to precede adverse effects on individuals or popu lations in this laboratory study. (C) 1997 Academic Press.