Arsenic
| Arsenic | |
|---|---|
| Properties | |
| Atomic symbol | As |
| Atomic number | 33 |
| Classification | Metalloid |
| Atomic mass | 74.9 amu |
| Other Information | |
| 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 |
| Obtained from | Mispikel |
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. Many of its compounds are highly toxic. 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.
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.”[1]
