Question

In the body, mercury's toxic effects are known to result from its ability to disrupt and insert into S-S bonds in critical enzymes. Fish, particularly tuna, which contain high levels of methylmercury are frequently found to also have high levels of selenium. Given the low rate of mercury poisoning even in populations where large quantities of fish are consumed, this has led some to speculate that selenium serves to protect against mercury poisoning. Explain the chemical basis for this theory

Answer 1

1. Selenoenzymes prevent and reverse oxidative damage THAT CAUSE BY MERCURY IN brain and neuroendocrine tissues.
2. Hg has more binding affinities for Se hence selenium serves to protect against mercury poisoning.

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Selenium is a fundamental trace mineral that capacities as a cancer prevention agent and advances a solid safe framework. Selenium is required in astoundingly little sums, with suggested every day sums measured in the millionths of a gram (micrograms). Selenium is likewise poisonous in bigger sums. Selenium has solid hostile to malignancy impacts and is known to detoxify the body and expel substantial metals including Mercury

Dietary selenium (Se) status is conversely identified with vulnerability to methylmercury (MeHg) lethality. Mercury exposures that are consistently neurotoxic and deadly among creatures bolstered low dietary Se are far less genuine among those with typical Se admissions and are without discernible outcomes in those encouraged Se-advanced eating regimens. In spite of the fact that these impacts have been known since 1967, they have just of late turned out to be surely knew. Late reviews have demonstrated that Se-advanced eating regimens counteract MeHg lethality, as well as quickly turn around some of its most serious side effects. It is presently comprehended that MeHg is an exceedingly particular, irreversible inhibitor of Se-ward proteins (selenoenzymes).

Selenoenzymes are required to forestall and invert oxidative harm all through the body, especially in the cerebrum and neuroendocrine tissues. Hindrance of selenoenzyme exercises in these powerless tissues seems, by all accounts, to be the proximal reason for the neurotic impacts known to go with MeHg lethality. Since Hg's coupling affinities for Se are up to a million circumstances higher than for sulfur, its second-best restricting accomplice, MeHg unyieldingly sequesters Se, straightforwardly weakening selenoenzyme exercises and their union.