Abstract
The foods have essentially been screened during human history and basically chosen and rooted in culture. Clearly, most are not harmful to health. However, in everyday life, food poisoning does occur due to eating and drinking materials containing pollutants, like poisonous metals, for example. The toxic effects are dependent on the dose and quantity of exposure the biological half-life in each organ is important. Metal toxicity may be reduced by proteins with protective roles like metallothionein having a thiol group for example. In this report we describe the toxicity, risk assessment and risk management of poisonous metals in foodstuffs, with a particular focus on mercury and arsenic.
Methylmercury may be found in seafood. However, we must consider nutritional merit and balance benefit and risk by avoiding eating fish with high methylmercury concentrations.
Well water may also be a source of pollutants particularly in developing countries. Arsenic compounds are of particular importance in this regard and there is abundant epidemiological evidence of association with cancer development. In addition, experimental studies have indicated that dimethylarsinic acid which is major metabolite of arsenic in mammal is carcinogenic for the rat urinary bladder, and dimethylmonothioarsinic acid is one of its active metabolites. It is therefore essential that examination of drinking water be routinely enforced with development of clarification technology to ensure removal of trace amounts.
The risk management of the poisonous metal exposure is very important for Japanese who may be exposed to mercury and arsenic in marine products. For future comprehensive safety and risk management of foodstuffs, vigilance and accumulation of further data are required.
