Heavy metals at trace level in edible mussels (Mytilus galloprovincialis Lamarck) from the gulf of Trieste.

Abstract

The concentration of heavy metals (cobalt, nickel, copper, cadmium, mercury and lead), which are present at trace levels in the edible part of mussels (Mytilus galloprovincialis Lamarck) from hatcheries in the gulf of Trieste, is normally or log-normally distributed, according to a statistical test sensitive to asymmetry of the distribution. A log-normal distribution appears valid for describing nearly all trace metals, in particular toxic heavy metals like cadmium, mercury and lead. The frequency distribution of these metals has nearly the same asymmetry, although the one-way analysis of the variance shows that sample means come from different population means characterising the particular hatchery.