Seiya Yamaguchi

Inhibitory effect of methylmercury on the activity of glutathione peroxidase

Inhibitory effect of methylmercuric chloride (MMC) on the activity of glutathione peroxidase was studied using 100,000g supernatant of the liver homogenate from 10 male SPF Wistar rats in vitro. Marked inhibition of glutathione peroxidase activity was observed between concentrations of 5 × 10−6 and 5 × 10−5 m MMC, but the activity was hardly inhibited at concentrations less than 5 × 10−6 m MMC; inhibition was almost complete at concentrations greater than 5 × 10−5 m MMC.

Relationship between mercury content of hair and amount of fish consumed.

A GREATER amount of mercury has been found in the scalp hair of the Japanese than in the scalp hair of Americans living either in Japan or in the United States (1). The reason has been attributed to the abnormal exposure of the Japanese to mercurial pesticides used for agricultural purposes. Recent investigations to determine the amount of mercury in human scalp hair have suggested a positive correlation with the intake of alkylmercury compound in foods (2, 3). Several observations on the amount of methylmercury in marine products also have been reported (4, 5). Consequently, arguments concerning the allowable concentration of mercury in foods have arisen (6). While extensive studies of the amount of mercury in marine products have not yet been reported, data on the mercury content of a limited number of species of fish and shellfish eaten by the Japanese are given in table 1. We have attempted to study how the mercury compound in marine products influences mercury metabolism in the bodies of persons living in different environments who have different food habits. The design of the study was influenced by the following premises. 1. The mercury content of scalp hair will increase according to the intake of methylmercury compounds (2). 2. Fish caught in an area where alkylmercury compounds are known to pollute the water contain a large amount of mercury (7); 40 to 90 percent of the fishs total mercury content is composed of methylmercury compound. 3. It is recognized that fish caught in unpolluted natural waters contain a certain amount of methylmercury compound. The amount fluctuates according to the size and age of the fish and as yet undetermined biological characteristics of fish.

Effects of environmental temperatures on the toxicity of methylmercury in rats.

The study was designed to examine the influence of environmental temperatures on subacute (5 mg/kg/3 days) methylmercury toxicity in rats by observations of mortality, manifestation of the hindleg-crossing phenomenon, and measurement of total and methylmercury in tissue samples.

Occurrence of Alkylmercury Compound in Caustic Soda Factory

A compound resembling methyl mercury has been found in the area surrounding a caustic soda factory where only metallic mercury has been used in the manufacturing process. Most of methyl mercury occurs in the sludge of a treatment pit for effluent water that contains inorganic mercury. Chemical characteristics identifying the physical properties and toxicity of the compound all indicate the probability that the substance is methyl mercury.

Discovery of methyl mercury compound in dry batteries

Abstract The mercury compounds used in dry cell batteries are inorganic mercurials. This report clarifies the possible formation of methyl mercury compounds in the contents of batteries obtained on the market. Using gas chromatography-mass spectrometry it was confirmed that the substance extracted from the ingredients is methyl mercury chloride.