Adaptation of the polychaete Neanthes Arenaceodentata to copper

Neanthes arenaceodentata were exposed to 292, 146, 92 and 56 μg litre⁻¹ Cu (measured) and control seawater after a 27-day pre-exposure to a sublethal concentration of Cu (10, 16 and 28 μg litre⁻¹ and control) to determine if the worms increased their tolerance to Cu after the pre-treatment. The worms pre-exposed to 28 μg litre⁻¹ Cu were significantly more resistant to Cu toxicity than control and 10 and 16 μg litre⁻¹ Cu pre-exposed worms. For example, the time to 50 % mortality at 92 μg litre⁻¹ Cu was 18 and 11 days for worms pre-exposed to 28 μg litre⁻¹ Cu and control conditions, respectively. The net rate of Cu uptake during the toxicity test was lower for worms pre-exposed to 28 μg litre⁻¹ Cu than for the control and 10 and 16 μg litre⁻¹ Cu pre-exposed worms. For example, the net rate of Cu uptake at 292 μg litre⁻¹ Cu by worms pre-exposed to 28 μg litre⁻¹ Cu and control conditions was 42 and 102 μg g⁻¹ day ⁻¹, respectively.