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Arsenic that is naturally occurring can contaminate the soil, just as it does the groundwater. This presents a possible arsenic exposure by use of products containing tobacco, because the tobacco plant grows from the soil and can become infiltrated with the arsenic. [3]
Arsenic is a moderately abundant element in Earth's crust, and although many arsenic compounds are often considered highly toxic to most life, a wide variety of organoarsenic compounds are produced biologically and various organic and inorganic arsenic compounds are metabolized by numerous organisms.
The arsenic (As) cycle is the biogeochemical cycle of natural and anthropogenic exchanges of arsenic terms through the atmosphere, lithosphere, pedosphere, hydrosphere, and biosphere. Although arsenic is naturally abundant in the Earth's crust, long-term exposure and high concentrations of arsenic can be detrimental to human health. [1] [2]
Arsenic is bioaccumulative in many organisms, marine species in particular, but it does not appear to biomagnify significantly in food webs. [221] In polluted areas, plant growth may be affected by root uptake of arsenate, which is a phosphate analog and therefore readily transported in plant tissues and cells.
Arsenate is the major arsenic form in oxidizing environments; however, in one study, bacteria from arsenic-contaminated soil at a smelter site was able to reduce As(+5) to As(+3) under anaerobic conditions at arsenic concentration as high as 75 mg/L. [3] Arsenate-respiring bacteria and Archaea have also recently been isolated from a diversity of natural environments, including freshwater ...
Arsenic promotes growth in chickens and rats, and may be essential for humans in small quantities. Arsenic has been shown to be helpful in metabolizing the amino acid arginine. There are 7 mg of arsenic in a typical 70 kg human. [14] Antimony is not known to have a biological role. Plants take up only trace amounts of antimony.
In humans, arsenic of these valences is readily absorbed by the gastrointestinal tract, which accounts for its high toxicity. Pentavalent arsenic tends to be reduced to trivalent arsenic and trivalent arsenic tends to proceed via oxidative methylation in which the trivalent arsenic is made into mono, di and trimethylated products by ...
Arsenic poisoning (or arsenicosis) is a medical condition that occurs due to elevated levels of arsenic in the body. [4] If arsenic poisoning occurs over a brief period of time, symptoms may include vomiting, abdominal pain, encephalopathy, and watery diarrhea that contains blood. [1]