In sub lethal spiked-sediment toxicity tests, growth of a freshwater amphipod, H. azteca, and a midge, C. tenants, was significantly reduced at concentrations of 89.8 mg•kg-1 and 496 mg•kg-1 , respectively (Milani et al. 1996). Other freshwater spiked-sediment toxicity tests did not demonstrate adverse effects at concentrations of Cu that were known to occur in aquatic environments (Environment Canada 1998). Sub lethal effects of Cu to marine organisms in spiked-sediment toxicity tests include delayed predator avoidance response (i.e., burial) in the clams P. stamina and May are aria.