Genetic effects in Helix aspersa near a coal plant revealed by the micronucleus test

Coal plants can be a major source of mutagenic pollutants. In this study we used the common land snailHelix aspersa, to detect the mutagenic effect of pollution from a coal plant in central Italy applying the micronucleustest (MN) on snail’s haemocytes and evaluating trace elements concentration (As Cd, Pb, Hg, and Zn) in soil and snails. Snailsfrom a biological farm were exposed for 13 days in five locations at different distances from the plant. Wild snailscollected in the same locations were also analysed. MN frequency in exposed snailswas significantly higher in four locations within 10 km from to the plant, with respect to the control and the farthest location. Comparing the MN frequency between farmed and wild snails, a significantly higher frequency emerged for the exposed snailsin all locations except the farthest, likely indicating adaptation or selection of the wild organisms due to chronic exposure to pollutants. In natural snailssignificantly higher MN frequencies with near the plant emerged as well. Trace elements analysis showed significant correlations between MN frequencies and both Zn and As concentrations in soil, for both exposed and wild snails, and Zn and Pb concentrations in exposed snails. Our results were consistent with those previously obtained when evaluating primary DNA damage in natural snailsfrom the same area and show that the snailsnear the plant were affected by a permanent cytogenetic damage. Moreover, they confirm the suitability of snailsfor biomonitoringthe presence of pollutants with mutagenic effect.