A sensitive monitoring system was set up to continuously measure dissolved oxygen concentrations in order to study the effects of copper toxicity on the hard clam, Meretrix lusoria. Respiration in M. lusoria was repressed within 1 hr after adding the hard clams to sea water containing copper concentrations greater than 14 ppb at both 25°C and 30°C. Liver tissue of M. lusoria began to accumulate copper within 24 hr, when the hard clams were submerged in sea water at 30°C with a concentration of 18.6 ppb copper. However, the liver did not accumulate copper within 14 d, when the hard clams were treated with either 15.4 or 17.3 ppb copper. Neither foot nor gill tissue accumulated copper within 14 d for treatments with 15.4, 17.3, and 18.6 ppb, respectively. The results indicate that continuous measurement of respiration was more efficient in revealing the copper toxicity in the hard clam than the tissue accumulation test.
Copper, Continuous recording of respiration method, Bivalvia
