Lukashev D. Ecological normalization of heavy metal pollution of freshwater ecosystems of Ukraine using bioaccumulators (on an example of mollusks)

The researches of ecological and biochemical particularity of metal accumulation activity by freshwater mollusks from territory of Ukraine is motivated their use as bioconcentrators and biomonitors for organizing of ecological monitoring of heave metal pollution of biotic components of water ecosystems. The gastropod mollusk Lymnaea stagnalis and three bivalve mussels Dreissena bugensis, Anodonta anatina and Unio tumidus have been established as best concentrators of heavy metals. These specieses are accumulated of metals in wide range concentration with absence of toxic effect, they are motionless, they are wide distributed and have a long lifetime, may be infallible identified to the species, and are easy collect and process. The method of calculation of metals background concentrations in the tissues of mollusks-bioaccumulators is based as a criterion of quantitative evaluation of biotic components pollution in freshwater ecosystems. The background metal concentration in mollusk body is calculated as median absolute deviation value (Мех±2MAD). Upper background level has been suggest as an ecological standard for detect of water ecosystem pollution by bioavailable forms of heavy metals. Use of ecological methods of monitoring was allowed identified of regions of Ukraine which water ecosystems characterized by signs of pollution that conformed of statistical significant exceeding of upper background level of heavy metal concentration in the mollusk's tissue. These polluted ecosystems were located in area with intensively industrial development and high human population density.