A fast indicator for detecting gross pollution by hazardous chemicals

Median survival, 10% mortality, and 10% turnover times of rainbow trout, Salmo gairdneri Richardson, were compared in solutions containing copper or cyanide ions. For all concentrations of poisons (0.5, 1.0, and 2.0 g.nr³ of copper as Cu²⁺ and 0.3, 0.5, 1.0, and 5.0 g.m³ of cyanide, as KCN), the times for turnover were the least. These were short enough (4.5–96 min) to be of use in monitoring waters which are being abstracted by water treatment plants; the method may be generally applicable for detection of gross forms of pollution by hazardous chemicals.