Application of the micronucleus and comet assays to mussel Dreissena polymorpha haemocytes for genotoxicity monitoring of freshwater environments

Assessment of DNA damage is of primary concern when determining the pollution-related stress in living organisms. To monitor genotoxicity of the freshwater environments we used micronucleus (MN) and comet assay on Dreissena polymorpha haemocytes. Caged mussels, collected from the river Drava, were transplanted to four monitoring sites of different pollution intensity in the river Sava. Exposition lasted for a month. The baseline level of MN frequencies in the haemocytes of mussels from reference site (river Drava) was 0.5parts per thousand. No increase in MN frequency was found in mussels from the medium-polluted site (Zagreb) in the river Sava while other, more polluted sites showed higher MN frequencies ranging from 2.77parts per thousand (Lukavec) and 3.1parts per thousand (Oborovo) to 5.2parts per thousand (Sisak). Results from comet assay showed concordance with MN assay in indicating intensity of DNA damage. The use of haemocytes from caged, nonindigenous mussels in MN and comet assay proved to be a sensitive tool for the freshwater genotoxicity monitoring. (C) 2003 Elsevier Science B.V. All rights reserved.