Effects of chlorpyrifos on cholinesterase activity and stress markers in the tropical reef fish Acanthochromis polyacanthus

► One of five studies testing the toxicity of contemporary insecticide to coral reef fish. ► Chlorpyrifos at 1 and 10 μg/L inhibited ChE activity by 26% and 49% after 96 h. ► Fish muscle tissue possesses three types of ChE including two atypical forms. ► Hepatic coenzyme Q antioxidant form increased after 6 h at 10 μg/L. ► Study shows the value of using multiple markers to detect sub-lethal toxic effects.