Arsenic poisoning with

Three Singapore patients with chronic arsenic poisoning with characteristic skin changes had taken Chinese herbal remedies for many years to treat their asthma two had cancers likely to be due to arsenic (150). 

Rittey DAW (1949). Treatment of accidental arsenical poisoning with dimercaprol. Lancet, 2, 719. 

The element is a steel gray, very brittle, crystalline, semimetallic solid it tarnishes in air, and when heated is rapidly oxidized to arsenous oxide with the odor of garlic. Arsenic and its compounds are poisonous. 

Kreppel, H., K. Kolb, F.X. Reichl, B. Fichtl, and W. Forth. 1988. Pretreatment with low doses of cadmium or zinc decreases lethality in mice acutely poisoned with arsenic. Pages 594-600 in Trace Element Analytical Chemistry in Medicine and Biology. Walter de Gruyter, Berhn. 

The first time the body realizes that arsenic has been incorporated is when the redox activity (as above) proceeds at potentials when nitrogen or phosphorus are inert. By the time we detect the arsenic poisoning (i.e. we feel unwell), it is generally too late, since atoms of arsenic are covalently bound within body tissue and cannot just be flushed out or treated with an antidote. The arsenic sequesters electrons that might otherwise be involved in other relay cycles, which is a concurrent kinetic process see Figure 8.16. 

Henry Adams) he found himself invariably taking for granted, as a political instinct, with out waiting further experiment, - as he took for granted that arsenic poisoned, - the rule that a friend in power is a friend lost. 

Arsine is used as a reducing agent and to synthesize many organoarsine derivatives. It is also used as a doping agent for solid state electronic components. Earlier, it was used as a military poison gas. It does not occur freely in nature but is susceptible to form upon contact of arsenic compounds with acid in presence of a metal. Thus commercial acids stored in metal tanks and contaminated with arsenic impurities may produce arsine. 

Occupational and environmental poisoning with metals, metalloids, and metal compounds is a major health problem. Exposure in the workplace is found in many industries, and exposure in the home and elsewhere in the nonoccupational environment is widespread. The classic metal poisons (arsenic, lead, and mercury) continue to be widely used. (Treatment of their toxicities is discussed in Chapter 57.) Occupational exposure and poisoning due to beryllium, cadmium, manganese, and uranium are relatively new occupational problems, which present new and previously unaddressed problems. 

Management of chronic arsenic poisoning consists primarily of termination of exposure and nonspecific supportive care. Although empiric short-term oral chelation with unithiol or succimer for symptomatic individuals with elevated urine arsenic concentrations may be considered, it has no proven benefit beyond removal from exposure alone. Preliminary studies suggest that dietary supplementation of folate—thought to be a cofactor in arsenic methylation—might be of value in arsenic-exposed individuals, particularly men, who are also deficient in folate. 

Abdominal examination may reveal ileus, which is typical of poisoning with antimuscarinic, opioid, and sedative drugs. Hyperactive bowel sounds, abdominal cramping, and diarrhea are common in poisoning with organophosphates, iron, arsenic, theophylline, A phalloides, and A muscaria. 

Iron is widely used in over-the-counter vitamin preparations and is a leading cause of childhood poisoning deaths. As few as 10-12 prenatal multivitamins with iron may cause serious illness in a small child. Poisoning with other metals (lead, mercury, arsenic) is also important, especially in industry. See Chapters 33, 56, and 57 for detailed discussions of poisoning by iron and other metals. 

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