Heavy metal poisoning mercury

Another familiar historical case of heavy metal poisoning occurred in the mid-19th century, when hatters used a solution of mercury(II) nitrate to help shape the hats they made. When the mercury was inhaled or ingested, it caused damage to a hatter s nervous system frequently mental disorders resulted. Thus originated the expression "mad as a hatter."... 

The first chelating agent developed as an antidote to a heavy metal poison was 2,3-dimereaptopropanol (dimercaprol, British Anti-Lewisite, BAL). Originally intended for use on victims of the arsenical vesicant poison gas Lewisite52, it has since proved efficacious in the treatment of antimony, gold and mercury poisoning as well as... 

Along with mercury and lead, cadmium (Cd) is one of the big three heavy metal poisons. Cadmium occurs as a constituent of lead and zinc ores, from which it can be extracted as a byproduct. Cadmium is used to electroplate metals to prevent corrosion, as a pigment, as a constituent of alkali storage batteries, and in the manufacture of some plastics. 

Toxic heavy metals, such as cadmium, lead, and mercury, are sulfur seekers that bind strongly with thiol groups, which is one of the ways in which they interact adversely with biomolecules, including some enzymes. Advantage has been taken of this tendency to use thiols in chelation therapy in heavy metal poisoning. Among the thiols tested for this purpose are meso-2,3-dimer-captosuccinic acid, diethyldimercapto succinate, a-mercapto-P-(2-furyl), and a-mercapto-P-(2-thienyl) acrylic acid.3 The structural formulas for the first two are... 

There is limited evidence to recommend combined chelation and blood purification therapy for other heavy metal poisonings, such as copper, mercury, arsenic, and thalhum. There are case reports, however, outlining several such attempts. Treatment of cupric sulfate ingestion by dimercaprol and penicillamine chelation followed by hemoperfusion and hemodia-filtration has been reported [57]. An interesting case of inorganic mercury poisoning treated with DMPS chelation and continuous venous-venous hemodiafiltration (CVVHDF) was also reported [58]. It should be noted that treatment continued for 14 days with a hmited total removal of mercury (<13% of the ingested dose) in... 

Indications Heavy metal poisoning (Arsenic, Gold, Mercury,... 

Heavy metal poisoning (lead, mercury, cadmium, uranium, thallium) Generalized aminoaciduria ... 

D-penicillamine is so named because it was first isolated as an amine, from the degradation products of penicillin by Abraham et al [87]. Later studies showed the characteristic chemical behavior of D-penicillamine which involve three types of reactions, formation of disulphide links, formation of thiazolidine rings, and formation of metal complexes and chelates [67]. It was first used in 1956 in the treatment of Wilson s disease [88]. D-penicillamine has since been used in the treatment of many diseases, such as cystinuria [89], rheumatoid arthritis [90-92], systemic sclerosis [93], primary bdiary cirrhosis [94], heavy metal poisoning due to lead [95], cadmium [%], and mercury [97], and hyperviscosity syndrome [99]. In rheumatoid arthritis, D-peni-cdlamine has been widely accepted as an effective second line treatment. Despite of its effectiveness, it causes many adverse effects, such as skin rashes [99,100], taste abnormalities [100,101], hepatic dysfunction [102-104], gastrointestinal toxiciiy [99,105], proteinuria [100,106], hematuria [107, 108], thrombocytopenia [92, 109], aplastic anemia [110], lupus-like syndrome [111, 112], Goodpasture s-tike pulmonary renal syndrome [113-115], vasculitis [116,117], myasthenia gravis [118-122], polymyositis [123, 124], and dermatomyositis [125]. 

Mercury forms strong covalent bonds with sulfur. If the sulfur happens to be in an amino acid (cystine, cysteine, methionine), in a protein, or an enzyme then poisoning can occur. One result of this interaction is that Hg accumulates in toe and finger nails as well as in hair. Almost everyone has some Hg in their nails and hair, but an excessive amount can indicate chronic heavy metal poisoning. A survey of Hg in the hair of 17 general population people indicated 6.0 2.9 ppm. Dentists had 9.8 4.7 ppm. 

D-penicillamine (D-3-mercaptovaline, Cuprimine), a breakdown product of penicillin, was, after the discovery of its chelating properties of copper ion (Fig. 2-6), introduced as an antidote to copper poisoning. It was also found useful in the treatment of Wilson s disease, where excess copper accumulation causes liver cell damage. Heavy metal poisoning treatment is not limited to copper. Mercury and lead poisoning are also successfully reversed. Formation of cysteine calculi (cystinuria) can also be reversed with penicillamine by forming a soluble disulfide compound. 

Mercury is a very dense (13.6 times denser than water), shiny liquid that has a surprisingly high vapor pressure for a heavy metal. Because mercury vapor is quite toxic, it must be stored in stoppered containers and handled in well-ventilated areas. Many instances of suspected mercury poisoning occurred in the days before its hazards were understood. 

Mercury has been involved in very serious outbreaks of widespread heavy metal poisoning. In faet, it has been responsible for health problems and thousands of deaths in Japan, Iraq, Pakistan, Canada, etc. 

Describe the consequences and the biochemical basis of thiamine deficiency. Compare the effects of heavy metal poisoning -with mercury or arsenite. 

In connection with the toxicity of selenium, it should be noted that arsenite presumably can overcome selenium poisoning and that selenium compounds have been used to treat heavy metal poisoning, arising from such metals as silver, cadmium, mercury and lead . This is thought to occur by altering the coordination of these metals (e.g. selenium compounds have a greater affinity for mercury and methyl mercury than do the sulfur analogs) as well as their retention and distribution in the body. 

I. Pharmacology. BAL (British anti-Lewisite, dimercaprol, 2,3-dimercaptopro-panol) is a dithiol chelating agent used in the treatment of poisoning by the heavy metals arsenic, mercury, lead, and gold. Because the vicinal thiol groups are unstable in aqueous solution, the drug is supplied as a 10% solution (100... 

A. Penicillamine may be used to treat heavy metal poisoning caused by lead (if patient is intolerant to succimer, then penicillamine may be used alone for minor intoxication or as adjunctive therapy after calcium EDTA or BAL in moderate to severe intoxication), mercury (after initial BAL therapy and if intolerant of succimer), and copper (succimer may be an alternative for mild to moderate poisoning). 

Poisons can be acute (with immediate effect, e.g., hydrogen cyanide (HCN)) or chronic (referring to the systemic damage done after repeated exposure to low concentrations over long periods of time, e.g., heavy metals like mercury, lead, cadmium and also vinyl chloride). The chemicals most often associated with chronic toxicity are also carcinogens (e.g., benzene, cadmium compounds), which are problematic because when, if at all, the... 

Heavy-metal poisoning is treated by administering chelating agents—substances that combine with the metal ions and hold them very tightly. One effective antidote is the chelating agent ethylenediaminetetraacetic add, or EDTA, which will chelate all heavy metals except mercury. 

Uses Chelating agent antidote to arsenic, gold, and mercury poisoning antidote to Lewisite detoxicant for heavy metal poisoning... 

The compound 2,3-dimercaptopropanol (HSCH2CHSHCH2OH), commonly known as British Anti-Lewisite (BAL), was developed during World War I as an antidote to arsenic-containing poison gas. (a) If each BAL molecule binds one arsenic (As) atom, how many As atoms can be removed by 1.0 g of BAL (b) BAL can also be used to remove poisonous heavy metals like mercury (Hg) and lead (Pb). If each BAL binds one Hg atom, calculate the mass percent of Hg in a BAL-Hg complex. (An H atom is removed when a BAL molecule binds an Hg atom.)... 

In summary, while hair analysis has been used to detect certain types of heavy metal poisoning (e.g., lead, arsenic, mercury) in populations, its value on an individual basis remains to be established. There are a number of limitations to hair analysis both in terms of analytical procedures and in interpretation of results. For example, the relationship between hair concentration of a trace element or of a vitamin and the concentration of other body tissues is unknown. Basically, hair analysis is of limited value for assessing mineral status and questionable for assessing vitamin status. 

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