Search results
Results from the WOW.Com Content Network
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]
The carcinogenic effect of arsenic arises from the oxidative stress induced by arsenic. Arsenic's high toxicity naturally led to the development of a variety of arsenic compounds as chemical weapons, e.g. dimethylarsenic chloride. Some were employed as chemical warfare agents, especially in World War I.
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.
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.
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 ...
As it has low water solubility, it tends to stay at the water surface, so organisms that live there are most affected. DDT found in fish that formed part of the human food chain caused concern, but the levels found in the liver, kidney and brain tissues was less than 1 ppm and in fat was 10 ppm, which was below the level likely to cause harm.