Effect of Complexation on Toxicity of Copper to Fishes

Abstract

Copper (Cu) is highly complexed by carbonate and hydroxide ions in natural waters and this complexation determines the concentration of copper species in solution. Results of detailed equilibrium calculations on data from bioassays where alkalinity, pH, hardness, and total copper concentration are different indicate that copper(II) is the chemical species that is toxic to fishes and that alkalinity is the factor controlling copper(II) concentration.