Arsenic trioxide toxicity

Arsenic Peroxides. Arsenic peroxides have not been isolated however, elemental arsenic, and a great variety of arsenic compounds, have been found to be effective catalysts ia the epoxidation of olefins by aqueous hydrogen peroxide. Transient peroxoarsenic compounds are beheved to be iavolved ia these systems. Compounds that act as effective epoxidation catalysts iaclude arsenic trioxide, arsenic pentoxide, arsenious acid, arsenic acid, arsenic trichloride, arsenic oxychloride, triphenyl arsiae, phenylarsonic acid, and the arsenates of sodium, ammonium, and bismuth (56). To avoid having to dispose of the toxic residues of these reactions, the arsenic can be immobi1i2ed on a polystyrene resia (57). 

Trimethyl arsine [593-88-4] C H As, has been identified as the toxic volatile arsenical, once known as "Gosio gas," produced by the reaction of certain molds that grow on wallpaper paste and react with inorganic arsenic compounds present in the paper. A number of microorganisms can methylate arsenic trioxide and other arsenic-containing compounds to yield trimethylarsine. These microorganisms include Scopulariopsis brevicaulis Candida humicola and Gliocladium roseum (72). 

Gift-mehl, n. crude powdered arsenic trioxide, -mittel, n. antidote. -nebel, m. (Mil.) toxic smoke, -nebelkerze, /. (Mil.) toxic smoke candle, -nebelwolke, /. (Mil.) toxic... 

Solubility in water and body fluids appears to be directly related to toxicity (the low toxicity of elemental arsenic is attributed to its virtual insolubility in water and body fluids, whereas the highly toxic arsenic trioxide, for example, is soluble in water to 12.0 g/L at 0°C, 21.0 g/L at 25°C, and 56.0 g/L at 75°C). 

Dimethylarsinic acid is the major metabolite of orally administered arsenic trioxide, and is excreted rapidly in the urine (Yamauchi and Yamamura 1985). The methylation process is true detoxification, since methanearsonates and cacodylates are about 200 times less toxic than sodium arsenite (NAS 1977). The marmoset monkey (Callithrix jacchus), unlike all other animal species studied to date, was not able (for unknown reasons) to metabolize administered As+5 to demethylarsinic acid most was reduced to As+3. Only 20% of the total dose was excreted in urine as unchanged As+5, and another 20% as As+3. The rest was bound to tissues, giving distribution patterns similar to arsenite (Vahter and Marafante 1985). Accordingly, the marmoset, like the rat, may be unsuitable for research with arsenicals. 

It has been shown that all doses of arsenic trioxide are characterized by different toxicokinetics parameters. Arsenic compounds have long half-times and the tendency to accumulate in the body. The excretion rate decreased with decreasing blood concentration. The present study confirms the ability of toxicokinetic models to improve the study of various toxic substances and to estimate the Biological Threshold Limit Values. 

Arsenic is highly toxic, and indeed much speculation has surrounded arsenic poisoning as the cause of death of Napoleon Bonaparte, on account of the levels of As in the Emperor s hair (perhaps derived from fungal activity on a green pigment present in the wallpaper of his apartments in St. Helena). Arsenic trioxide has been approved by the Food and Drug Administration (FDA) of the USA for the treatment of acute promyelocytic anaemia in adult patients who fail to respond to other chemotherapy, or have relapsed disease. 

Most of the compounds of arsenic are toxic when in contact with the skin, when inhaled, or when ingested. As with arsenics cousin phosphorus above it in group 15 of the periodic table, care must be taken when using arsenic. The compound arsenic trioxide (As O ), an excellent weed-killer, is also carcinogenic. Copper acetoarsenite, known as Paris green, is used to spray cotton for boll weevils. A poisonous dose of arsenic as small as 60 miUigrams can be detected within the body by using the Marsh test. 

Inhaled arsine is oxidized to form elemental trivalent arsenic (As ) and arsenous oxide (AS2O3), two human carcinogens. Excess cancers from trivalent arsenic and arsenic trioxide have been associated with cumulative lifetime arsenic exposure. Exposure to arsine above 0.004ppm is associated with increased urinary arsenic excretion, indicating exposure to arsenic. Current exposure limits may not prevent potential chronic toxicity. ... 

P listed wastes Highly toxic chemicals that are rarely used, are banned, or are permitted for limited uses Acrolein, arsenic trioxide, dieldrin, heptachlor, me-thiocarb, osmium tetroxide, 2-propenal... 

Arsenic trioxide is a chemotheraputic agent used to treat leukemia that is unresponsive to first line agents. It is suspected that arsenic trioxide induces cancer cells to undergo apoptosis. The enzyme thioredoxin reductase has recently been identified as a target for arsenic trioxide. Due to the toxic nature of arsenic, this drug carries signihcant risks. 

Arsenic trioxide. Arsenic is a heavy metal that can exert toxic, poisonous effects. Therapeutic dosages of arsenic trioxide (Trisenox), however, may limit the growth of certain leukemias such as acute promyelo-cytic leukemia.11 However, because of its potential toxicity, arsenic trioxide is not usually an initial treatment, but is reserved for patients who relapse or who are resistant to other treatments. Although the exact mechanism of action is unclear, this drug apparently induces several cytotoxic effects by directly damaging DNA and proteins that regulate DNA synthesis and replication. 

Naturally toxic substances may also be included in compounds such as paints, ceramic glazes, and dyes. Natural poisons have long been used as insecticides in collections that contain materials susceptible to attack by pests. The most common among these compounds are arsenolite (arsenic trioxide) and mercury. 

Arsenic was, without doubt, important in the successful treatment of S5q>hilis. The drug Salvarsan (arsphenamine) was discovered by Paul Erhlich during a systematic study of arsenic compounds for a potential cure for syphilis. Salvarsan is a synthetic organic chemical that contains arsenic he had tried more than 600 chemicals when he happened on this one. His quest was based on the behef that he could find a substance that was selectively toxic to the organism that causes syphilis (a spirochaete) but less toxic to the patient, a magic bullet . Only recently, arsenic trioxide (the form of arsenic commonly used for homicide) was licensed by the... 

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