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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]
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]
Research has not been conducted to determine whether small amounts of arsenic may play a role in human metabolism. [17] [18] However, arsenic poisoning occurs in multicellular life if quantities are larger than needed. Arsenic contamination of groundwater is a problem that affects millions of people across the world.
In humans, arsenic can cause cancer in the bladder, skin, lungs and liver. One of the major sources of arsenic exposure in humans is contaminated water, which is a problem in more than 30 countries in the world. Humans tend to encounter arsenic by "natural means, industrial source, or from unintended sources."
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.
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 ...
Then, they can bind to and interfere with the functioning of vital cellular components. The toxic effects of arsenic, mercury, and lead were known to the ancients, but methodical studies of the toxicity of some heavy metals appear to date from only 1868. In humans, heavy metal poisoning is generally treated by the administration of chelating ...
Also, the lack of immediate human toxicity does not mean the substance is environmentally nonhazardous. For example, tanker truck-sized spills of substances such as milk can cause a lot of damage in the local aquatic ecosystems: the added biological oxygen demand causes rapid eutrophication , leading to anoxic conditions in the water body.