|Atomic mass||74.9 amu|
|Date of discovery||Arsenic has been known since ancient times.|
|Name of discoverer||Unknown|
|Name origin||From the Greek arsenikos and Latin arsenicum.|
|Uses||Arsenic conducts electricity and is a poison|
Arsenic is a chemical element with an atomic number of 33, and atomic mass of approx. 74.92, and is the 20th most abundant element in the Earth's crust. It bears a chemical similarity to phosphorus which is the cause of some of its toxic effects. The most common charges for arsenic to possess are -3, +3, and +5.
Many of its compounds are highly toxic. Arsenic toxicity is often the result of the inhibition of certain enzymes, commonly those pertinent to metabolism; specifically, it replaces phosphorus is certain reactions, which can prevent the reaction products from functioning appropriately. This can lead to cellular death, which may in turn leads to tissue death and necrosis, and, if left untreated, death.
While chronic exposure to arsenic can cause several types of cancer, such as bladder and skin, it is also used as an anticancer agent for others, such as acute promyelocytic leukemia.
Cacodylic acid (AsOH(CH3)2), an organic form of arsenic, is a defoliant and was used in the Vietnam War under the name Agent Blue. In the United States, it is sometimes sprayed on cotton fields, where it causes the plants to desiccate, making harvesting of cotton bolls easier. Cacodylic acid is also the primary excreted metabolic product of arsenic in humans.
Oklahoma State University veterinary professor Dr. Billy Clay testified that the amount of arsenic used in animal agriculture is insignificant compared to what’s already in the environment. “Arsenic is very common in nature,” Clay said. “It's everywhere.”
Arsenic as an essential trace element
Scientists have been examining arsenic's role as a trace element essential to human health.
- Despite Arsenic’s reputation as a highly toxic substance, this element may actually be necessary for good health. Studies of animals such as chickens, rats, goats and pigs show that it is necessary for proper growth, development and reproduction. In these studies, the main symptom of not getting enough arsenic was retarded growth and development.
- ... your brain actually requires tiny concentrations of arsenic - rat poison - to function properly.
- .. our brains require a tiny amount of arsenic in order to function properly.
- Despite its notoriety as a deadly poison, arsenic is an essential trace element for some animals, and maybe even for humans, although the necessary intake may be as low as 0.01 mg/day.
- Desirable arsenic concentrations in the body seem to be reasonable. This consideration results in the conclusion that arsenic could play an essential role in human health. Thus, reference arsenic concentrations in different human tissues and body fluids should be established in order to recognize not only arsenic intoxication, but also arsenic deficiency.
- The Role of Elements in Life Processes | Mineral Information Institute
- Mercury FAQs
- Arsenic (As) - Chemical properties, Health and Environmental effects
- Essential trace elements in humans. Serum arsenic concentrations in hemodialysis patients in comparison to healthy controls - Biol Trace Elem Res. 1993 Apr;37(1):27-38.
|Periodic Table of the Elements|