AN IN-VITRO BINUCLEATED BLOCKED HEPATIC CELL TECHNIQUE FOR GENOTOXICITY TESTING IN FISH

The main objective of this work was to develop and use a binucleated m ethod which depends on the cytokinesis blocking of hepatic cells in fi sh to enable the scoring of micronuclei in cells that have completed o nly one division after genotoxic insult. The use of this novel techniq ue in a study of the influence of some pollutants in vitro (selenium, mercury, methylmercury, and their mixtures) allows evaluation of the r isk from exposure to these water pollutants under field and laboratory conditions. The frequencies of micronuclei in trout hepatic cells in vitro were elevated in a dose-dependent manner when compared to the re levant controls. Addition of Se(IV) reduced the frequencies of micronu clei in treatments with both forms of mercury. inorganic mercury was f ound to be partly methylated when exposed to trout liver cells in vitr o. The potential contribution of the fish binucleated hepatic techniqu e to the toxicity assessment of the chemicals investigated is discusse d.