Genotoxic potential of marine sediments from the North Sea

The alkaline comet assay is a method for detecting DNA strand breaks and al kali labile sites in individual cells. An in vitro system was used to inves tigate the genotoxic potential of complex mixtures such as organic extracts of marine sediments. DNA damage was induced in leukocytes isolated from ca rp (Cyprius carpio) by exposure to organic sediment extracts from the North Sea or hydrogen peroxide as positive control, respectively. The minimum co ncentration for significant effects ranged from 1 to 40 mg sediment dry wei ght per milliliter assay volume. The sensitivity of the method was enhanced by using the DNA repair inhibitor, 1-beta-D-arabinofuranosylcytosine (ara C). From the results, it can be suggested that total organic carbon (TOC) a s well as the different compositions of contaminants present in the sedimen t extracts may contribute to the genotoxic effects observed. The comet assa y can be applied successfully as an in vitro bioassay for investigations on genotoxicity of marine sediment extracts. (C) 2000 Elsevier Science B.V. A ll rights reserved.