MERCURY IN A PRIMARY CONSUMER (EOBANIA-VERMICULATA) COLLECTED NEAR A SHLOR-ALKALI COMPLEX

Mercury concentration in the land snail Eobania vermiculata, in plants , soil and air has been carried out in an area affected by a chlor-alk ali complex to evaluate the bioaccumulation processes in a primary con sumer. Very low values were measured in the snail shell (0.001-0.020 m ug g-1 d.w.), while in the soft tissue values (0.03-0.72 mug g-1 d.w.) comparable to those present in the plants were observed. The high mer cury levels (0.20-5.97 mug g-1 d.w.) found in the snail gut seem to in dicate the presence of a detoxification mechanism preventing the bioac cumulation of the metal. However mercury is transferred by the snail t o the subsequent levels of the food chain.