Retention of methyl mercury and inorganic mercury in rainbow trout Oncorhynchus mykiss (W): effect of dietary selenium

Abstract

The effects of dietary selenium on the retention of intraperitoneally injected organic and inorganic mercury in rainbow trout Oncorhynchus mykiss were investigated in the laboratory. Trout fed a selenite-supplemented (approximately 10 μg Se g −1) diet augmented the elimination of organic mercury from muscles, liver, kidney, bile and erythrocytes, but not from blood plasma, compared with trout fed a non-supplemented diet (approximately 1.5 μg Se g −1). Dietary selenium augmented the elimination of inorganic mercury in muscles and kidney, whereas liver, erythrocytes, blood plasma and bile were not affected. A total of 8 weeks exposure to food containing 10 μg Se g −1 increased the selenium concentration in the liver from 1 to 26 μg Se g −1. The selenium concentration in muscle was not affected by this exposure. Growth rate of the trout was not affected by the selenium exposure.