Mercury toxicity, experimental

It has been stated [11] that about 400 tonnes of mercury lie at the bottom of Minamata Bay near the point of discharge of mercury wastes and although further dumping was finally stopped in 1968, this cannot prevent the future possibility of conversion of inorganic to methyl mercury and its accumulation in fish. By 1973, sixty-five people had died from Minamata disease and many more had been crippled, blinded or otherwise affected. It is now known from experimental work with rabbits, that alkyl mercury can readily pass through the placental barrier in mammals [60] (p. 84) and this is borne out by the fact that a number of children were bom with symptoms of methyl mercury toxicity to women at Minamata who were not evidently themselves affected. 

Eaton RDP, Secord DC, Hewitt P. 1980. An experimental assessment of the toxic potential of mercury in ringed-seal Ever for adult laboratory cats. Toxicol Appl Pharmacol 55 514-521. 

Basic toxicity has been identified from careful observation and experimentation in the workplace and in the lab. Over the years, from the time of the ancient Greeks and Romans, and probably long before that, we have learned that exposure to certain substances can cause bodily harm. Hippocrates, the founder of medicine in Ancient Greece, described the occurrence of lead poisoning among lead miners and metal workers as long ago as 400 B.C. The Roman historian, Pliny, described in his encyclopedia in the second half of the first century A.D., the dangers of mercury poison-... 

Several recent epidemiological studies have involved examination of populations that consume unusually high levels of fish. One of these, conducted in the islands of the Seychelles, has not so far revealed behavioral and learning impairments in children whose mothers exhibited mercury levels (measured in hair) higher than those typically seen in the United States and European countries. But another study, conducted in the Faroe Islands, turned up evidence of cognitive and behavioral impairments in children. Scientists have struggled to understand why two well-done studies have produced such different outcomes, and some possible reasons have been suggested. The EPA and public health officials have acted on the basis of the Faroe data, out of both caution and also because they seem to be supported by other, more limited data, and by experimental studies. The debate is not so much about whether methylmercury is a developmental toxicant, but rather over the dose required. 

DOT CLASSIFICATION 6.1 Label Poison SAFETY PROFILE Poison by ingestion, intravenous, intraperitoneal, subcutaneous, and possibly other routes. An experimental teratogen. Other experimental reproductive effects. Mutation data reported. See also MERCURY COMPOUNDS. When heated to decomposition it emits toxic fumes of Hg. 

DFG MAK Confirmed Animal Carcinogen with Unknown Relevance to Humans SAFETY PROFILE A deadly human poison by inhalation. Poison by ingestion and intraperitoneal routes. An experimental teratogen. See also MERCURY COMPOUNDS, ORGANIC. Flammable when exposed to heat or flame can react with oxidizing materials. When heated to decomposition or on contact with acid or acid fumes it emits highly toxic fumes of... 

SAFETY PROFILE Experimental reproductive effects. Human mutation data reported. Reaction with ammonia or ammonium salts yields fulminating gold, a heat-, friction-, and impact-sensitive explosive similar to mercury and silver fulminates. See also GOLD COMPOUNDS and CHLORIDES. When heated to decomposition it emits toxic fumes of CT. 

CONSENSUS REPORTS lARC Cancer Review Group 3 IMEMDT 7,56,87 Animal Sufficient Evidence IMEMDT 12,183,76. Reported in EPA TSCA InventorjL SAFETY PROFILE Questionable carcinogen with experimental carcinogenic and tumorigenic data. When heated to decomposition it emits very toxic fumes of KaO, SOx, and NOx. Used as an analytical reagent for quantitative determination of mercury, gold, and copper. See also CARBAMATES. 

Although there is experimental evidence of nephrotoxicity from methyl mercury in animals, no reports of human renal toxicity from methyl mercury exposure have been identified [14]. 

Morrow PE, Gibb FR, Johnson L. Clearance of insoluble dust from the lower respiratory tract. Health Phys 1964 10 543-55. Clarkson TW. Human toxicity of mercury. The Journal ofTrace Elements in Experimental Medicine 1998 11 303-17. 

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