Mercury content in muscles of fish of the Selenga River and lakes of its basin (Russia)

Differences between the muscle mercury contents in fish from lakes Gusinoye and Karasinoye and the Selenga River may indicate an inconsiderable income of mercury in aquatic ecosystems with atmospheric precipitation, along with a more intensive migration of mercury with the riverine flux. The minimal concentration of mercury (less than 0.15 mg/kg, dry weight) has been registered in the muscles of Amur sleeper from Lake Karasinoye and of Baikal omul from Lake Baikal, while the maximal concentration (1.0-2.3 mg/kg, dry weight) has been revealed in the fish caught in the Selenga River delta (in predatory pike, Amur catfish, and perch, as well as in omnivorous roach and ide). The muscle metal content in dace decreased along the downstream direction.