Gastrointestinal tract arsenic

Inorganic arsenic salts are also present in pesticides, herbicides, fungicides, paints, and tobacco plants. If transmitted to water, they accumulate in fish, mollusks, crustaceans, and algae (Johansen et ah, 2000). Transformed into organic salts, they reach the gastrointestinal tract via food and are delivered to liver, spleen, kidneys, and lungs. Arsenic is deposited in skin, nails, and hair. 

There is limited evidence of carcinogenicity in experimental animals. However, in one report arsenic administered for 2 years in the drinking water of female mice was associated with an increased incidence in tumors involving lung, liver, gastrointestinal tract, and skin. ... 

Organic arsenicals are poorly absorbed from the gastrointestinal tract and are excreted mainly in feces (1). After their absorption, organic arsenicals are distributed throughout the body and rapidly excreted in the urine without being metabolized to a great extent. Elimination of the parenterally administered compounds is nearly complete within 24-48 h, while several days are required for elimination of the compounds from the gut. 

The gastrointestinal tract responds to a number of toxic substances, usually by pain, vomiting, or paralytic ileus (see Intestines, Section 6.4.5). Severe gastrointestinal pain is symptomatic of poisoning by arsenic or iron. Both of these substances can cause vomiting, as can acids, bases, fluorides, salicylates, and theophyllin. Paralytic ileus can result from ingestion of narcotic analgesics, tricyclic antidepressants, and clonidine. 

Treatment of inorganic arsenic poisoning involves decontamination procedures and use of the antidote BAL (British anti-lewisite compound 2,3-dime-rcaptopropanol). Use of demulcent to coat the gastrointestinal tract and the use of antibiotics is also recommended. Organic arsenic poisoning treatment involves only withdrawal of the feed involved, with recovery occurring in 3-5 days. Severely affected pigs should be culled. 

The bio-availabilities of these elements through the gastrointestinal tract vary markedly. Molybdenum, iodine, fluorine, and arsenic are apparently highly bio-available, whereas medium uptake occurs with haem iron, cobalt, zinc, chromium in the presence of a glucose tolerance factor, selenium, either as selenate or as organo selenium compounds, whereas only low bio-availability is experienced with non-haem iron,... 

Arsenic and arsenic compounds Skin, lung (liver, gastrointestinal tract, kidney)... 

HUMAN TOXICITY DATA no LD50/LC50 information found related to normal routes of occupational exposure Toxicity data, as referred to metallic arsenic, is as follows oral-man TDLo 76mg/kg/12Y-intermittent toxic effect carcinogenic oral-man TDLo 7857 mg/kg/55Y toxic effect skin oral-man TDLo 7857 mg/kg/55Y toxic effect gastrointestinal tract. 

Arsenic Inorganic arsenic salts All mucous surfaces Capillaries, gastrointestinal tract, hematopoietic system Dimercaprol, succimer, penicillamine... 

Clinical use The major uses of penicillamine are in the treatment of copper poisoning and of Wilson s disease. It is sometimes used as adjunctive therapy in gold, arsenic, and lead intoxication and in rheumatoid arthritis. The agent is water-soluble, well absorbed from the gastrointestinal tract, and excreted unchanged. 

As a result of wide distribution of arsenic in all environmental media, most people are now daily exposed to a measurable dose of arsenic. Recent studies increasingly find health effects at levels of exposure previously thought to be safe, and the threshold dose for health outcome continues to be progressively lowered. There is therefore a growing worldwide concern that a very large number of people are being chronically exposed to levels of arsenic that may be inimical to health. Chronic exposure to low levels of arsenic can affect the skin, liver, kidney, circulatory system, gastrointestinal tract, nervous system, and heart... 

Ingested arsenic compounds can be readily absorbed through the gastrointestinal tract into the bloodstream (57,58,73-80). The rate of absorption is dependent on the solubility and probably the chemical species of arsenic. Most of the arsenic compounds are metabolized in the body. Both parent arsenic compounds and their metabolites are further excreted into urine (11-15,57,58,76-80,92-96). The extent of metabolism and excretion depends on the chemical species of arsenic ingested. 

VI. Dosage and method of administration. Unithiol may be administered by oral. Intramuscular, or intravenous routes. The intravenous route should be reserved for treatment of severe acute intoxication by inorganic mercury salts or arsenic where compromised gastrointestinal or cardiovascular status may interfere with rapid or efficient absorption from the gastrointestinal tract. In animal models, oral unithiol did not increase the gastrointestinal absorption of mercuric chloride. 

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