Water-effect ratio of copper and its application on setting site-specific water quality criteria for protecting marine ecosystems of Hong Kong.

Generic water quality criteria (WQC) of a chemical are usually set based on results generated from toxicity tests which were conducted using standard laboratory water with well-controlled physiochemical properties. However, in natural aquatic environments, physiochemical characteristics, such as salinity, total suspended solid, total organic carbon and the co-existence of chemical contaminants, often vary spatially and temporally. These parameters can, in turn, alter the bioavailability of target chemicals and, thus, influence their toxicity to marine organisms.