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Some factors influencing susceptibility of rainbow trout to the acute toxicity of an ethyl mercury phosphate formulation (Timsan)

Donald F. Amend·William T. Yasutake·Reginald Morgan
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Abstract

This study determined the influence of water temperature (55–68° F), dissolved oxygen (4–12 ppm), water hardness as CaCO 3 (20–256 ppm), and chloride ions (to 2 mM) on the susceptibility of rainbow trout ( Salmo gairdneri ) to the acute toxicity of ethyl mercury phosphate (EMP). The fish were exposed for one hour to 0.125 ppm EMP, the active ingredient of Timsan, a commercial EMP formulation. The death rate because of the exposure to EMP increased with an increase in water temperature, a decrease in dissolved oxygen, and an increase in chloride ions; calcium appeared to have no effect. The effect of water temperature and dissolved oxygen was ascribed to changes in the respiration rate of the fish, and a chemical explanation is presented for the effect of chloride ions.

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Donald F. Amend, William T. Yasutake, Reginald Morgan. 1969. Some factors influencing susceptibility of rainbow trout to the acute toxicity of an ethyl mercury phosphate formulation (Timsan). https://doi.org/10.1577/1548-8659(1969)98%5B419%3Asfisor%5D2.0.co%3B2

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