A marine host-mediated assay for the detection of mutagenic compounds in polluted sea waters

Abstract

Marine water in heavily polluted areas may contain a variety of carcinogenic and mutagenic compounds (Phillips, 1978; Bend and James, 1978). Several methods have been developed to determine by chemical analysis the presence of carcinogens and mutagens in marine as well as fresh waters (Yevich and Borszez, 1976; Farley, 1976; Simmon et al., 1977; Lowe and Moore, 1978). Mussels, and many bivalves, can concentrate to a considerable extent substances present in the water (Bayne, 1976; Dunn and Stich, 1976; Mix, 1979). Extracts of mussels and other marine organisms spontaneously growing in polluted coastal areas of Great Britain and Florida were found by Parry et al. (1980) and Sparks et al. (1981), in experiments in vitro, to be mutagenic on yeast and bacteria. The Lagoon of Venice is heavily polluted, although to variable extents, by a number of chemical compounds, and data are available on the concentrations of several compounds in mussels and other marine organisms (Fossato et al., 1979). Battaglia and his group (1979) studied the modification of gene frequencies and the variation of heterozygosity level due to the effect of pollutants present in the Lagoon of Venice, on natural mussel populations and laboratory populations of the copepod Tisbe. In looking for a test more sensitive and with less manipulation than the techniques with extracts in vitro, we developed a host-mediated assay (h.m.a.). We used, as host organism, mussels grown in both clean and polluted areas, as well as clean mussels transferred for a period of time into polluted areas. We used 2 strains of yeast as genetic indicator microorganisms and then compared the results with those obtained by treating the same yeast strains, TA98 and TA100 of Salmonella typhimurium, with the corresponding mussel extracts. The use of h.m.a, for mutagenesis studies, where the organism under study is least manipulated during treatment, has been established as a reliable and sensitive method (Zeiger et al., 1972; Mailing, 1976; Pueyo et al., 1979).