Toxicity of Mercury Ions

The primary target of methyl mercury toxicity is the central nervous system [43]. 

The acute toxicity thresholds for inorganic mercury (typically as HgCl2) in freshwater organisms vary from 5 to 230pgT in crustaceans to 60 to 800pgT in fish. Methyl mercury is known to accumulate in muscle tissue, where it binds to the sulfhydryl groups of the muscle proteins. Inorganic mercury is poorly absorbed in comparison to the short-chain alkyl mercurials such as methyl mercury, and accumulates primarily in the Hver and kidney [42, 43]. 

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