Differences in Cd elimination from Mytilus californianus and Mytilus trossulus soft tissues

Field results have shown that Mytilus californianus is able to release its Cd concentrations significantly in just a few days. The existing paradigm s tates that Cd elimination from Mytilus soft tissues is a very slow process. This discrepancy was investigated in the laboratory, testing the effect of two Cd levels (10 and 1 mug l(-1)) on its release from Mytilus trossulus a nd M. californianus soft tissues. After exposure to 10 mug l(-1), both spec ies showed a significant uptake with no elimination after several days of d epuration. After exposure to 1 mug l(-1), the responses were different. No significant Cd uptake was seen in M. trossulus while in M. californianus up take was significant but returned to the background level after just 1 day of depuration. This response of M. californianus is consistent with that re ported from field studies. These results are important for environmental mo nitoring programs since M. californianus has been used as equivalent to oth er Mytilus species in the assessment of Cd pollution. (C) 2001 Elsevier Sci ence Ltd. All rights reserved.