Effects of cadmium onMurex trunculus from the adriatic sea. II. Oxygen consumption and acclimation effects

Marine snails (Murex trunculus) from the Adriatic Sea were exposed to cadmium in the laboratory under chronic (0.05 mg·L^–1) and acute 5 mg·L^–1) conditions. More than 5 mg·L^–1 cadmium were required to lethally damageMurex trunculus during an exposure of 96 hr. Compared with untreated animals, chronic exposure ofMurex trunculus to 0.05 mg Cd·L^–1 results in an elevated rate of oxygen consumption. The difference between the two groups of snails increases with time. After one month, a 10% greater loss in biomass in treated animals than in controls was observed, reflecting the higher energy expenditure during exposure to 0.05 mg Cd·L^–1. An acute cadmium shock of 5 mg Cd·L^–1 caused depression of oxygen consumption both in the control and in long-term preexposed snails to 0.05 mg Cd·L^–1. If pre-exposure to a low (0.05 mg·L^–1) concentration of cadmium lasted for a short time only (18 hr) a subsequent acute cadmium shock (5 mg·L^–1) did not lead to a depression of the rate of oxygen consumption.