Arsenic

=**Arsenic**=

Basic Information

 * Name:** Arsenic
 * Symbol:** As
 * Atomic Number:** 33
 * Atomic Mass:** 74.9216 amu
 * Melting Point:** 817.0 °C (1090.15 K, 1502.6 °F)
 * Boiling Point:** 613.0 °C (886.15 K, 1135.4 °F)
 * Number of Protons/Electrons:** 33
 * Number of Neutrons:** 42
 * Classification:** Metalloid
 * Crystal Structure:** Rhombohedral
 * Density @ 293 K:** 5.72 g/cm 3
 * Color:** Gray

Atomic Structure

 * ||  || **Number of Energy Levels:** 4
 * First Energy Level:** 2
 * Second Energy Level:**8
 * Third Energy Level:**18
 * Fourth Energy Level:**5 ||

Isotopes

 * ** Isotope ** || ** Half Life ** ||
 * As-71 || 2.7 days ||
 * As-72 || 26.0 hours ||
 * As-73 || 80.3 days ||
 * As-74 || 17.8 days ||
 * As-75 || Stable ||
 * As-76 || 26.3 hours ||
 * As-77 || 39.0 hours ||
 * As-79 || 9.0 minutes ||

Facts

 * Date of Discovery:** Known to the ancients
 * Discoverer:** Unknown
 * Name Origin:** From the Greek word //arsenikos// and the Latin word //arsenicum//
 * Uses:** Poison, conducts electricity, semiconductors
 * Obtained From:** mispickel

__Characteristics__ Arsenic naturally is found in many mines, in addition to being found with sulfur and other metals. Arsenic is a metalloid and can be transformed in to a pure elemental crystal. The primary use of this element is to aid in strengthening other elements. These elements include copper and lead. Arsenic can also be incorporated in substances such as pesticides, herbicides, and insecticides. This is due to its poisonous virtues. Arsenic is also used for the treatment of acute promyelocytic leukemia (in small doses thru intravenous) and a compound of arsenic is used to make light-emitting diodes (LEDs

__History__ Arsenic was discovered by Albertus Magnus in 1250. The word "arsenic" is derived from the Syriac word "zamiqa" meaning "yellow orpiment" and "potent". The substance has been long used for poison and involved in historic murders. It has also been referred to as the "Poison of Kings and the King of Poisons."


 * __Arsenic has had multiple applications since its discovery.__**


 * Military:** The United States used Arsenic as a chemical weapon after WWI in the form of lewisite (ClCH=CHAsCl2) until it was neutralized in the 1950s.


 * Medicine:** Prior to the use of Arsenic in chemical weapons it was used in medicine. It was used during the 18th, 19th and 20th century until it was replaced by modern antibiotics. In 2000 the FDA approved the use of arsenic in cancer treatment. An isotope, Arsenic-74 is used today to help locate tumors.


 * Alloy:** Arsenic also works well as an alloy with both lead and copper. It is used to with lead in car batteries to make them stronger.


 * Agriculture:** Arsenic is also used in agriculture because it kills insects, bacteria and fungus. Since 2009 the use of Arsenic has been ban in poultry and swine production, but is still permitted in other forms of agriculture.

//**Arsenic Poisoning**//- a medical condition when there is too much arsenic in the body. Arsenic poisoning comes mainly from ground water being ingested in the body. This is a global problem and even happens in developed countries. Symptoms include: headache, confusion, diarrhea and drowsiness. The organs affect are the lungs, skin, kidneys and liver. Severe cases led to comas then death.

Long term exposure can lead to deficiency in Vitamin A which then leads to night blindness and heart disease. The reason it is spread in drinking water is due to the high levels or arsenic salts in aqufiers. There are chemical and synthetic methods of treating arsenic poisoning but the biggest side effect to these treatments is hypertension, meaning high blood pressure. This can lead to cardiac arrest and other circulatory issues.

Signs and symptoms
Symptoms of arsenic poisoning begin with headaches, confusion, severe diarrhea, and drowsiness. As the poisoning develops, convulsions and changes in fingernail pigmentation called leukonychia may occur. When the poisoning becomes acute, symptoms may include diarrhea, vomiting, blood in the urine, cramping muscles, hair loss, stomach pain, and more convulsions. The organs of the body that are usually affected by arsenic poisoning are the lungs, skin, kidneys, and liver. The final result of arsenic poisoning is coma to death. Arsenic is related to heart disease (hypertension related cardiovascular), cancer, stroke (cerebrovascular diseases), chronic lower respiratory diseases, and diabetes.

Night blindness
Long term exposure to arsenic is related to vitamin A deficiency which is related to heart disease and night blindness. Research has shown that the inorganic arsenites (trivalent forms) in drinking water have a much higher acute toxicity than organic arsenates (pentavalent forms). The acute minimal lethal dose of arsenic in adults is estimated to be 70 to 200 mg or 1 mg/kg/day. Most reported arsenic poisonings are caused by one of arsenic's compounds, also found in drinking water, arsenic trioxide which is 500 times more toxic than pure arsenic.

Drinking water
Main article: Arsenic contamination of groundwater Chronic arsenic poisoning results from drinking contaminated well water over a long period of time. Many aquifers contain high concentration of arsenic salts. The World Health Organization recommends a limit of 0.01 mg/L (10ppb) of arsenic in drinking water. This recommendation was established based on the limit of detection of available testing equipment at the time of publication of the WHO water quality guidelines. More recent findings show that consumption of water with levels as low as 0.00017mg/L (0.17ppb) over long periods of time can lead to arsenicosis. From a 1988 study in China, the US protection agency quantified the lifetime exposure of arsenic in drinking water at concentrations of 0.0017 mg/L, 0.00017 mg/L, and 0.000017 mg/L are associated with a lifetime skin cancer risk of 1 in 10,000, 1 in 100,000, and 1 in 1,000,000 respectively. The World Health Organization contends that a level of 0.01 mg/L poses a risk of 6 in 10000 chance of lifetime skin cancer risk and contends that this level of risk is acceptable.

Occupational exposures
Industries that use inorganic arsenic and its compounds include wood preservation, glass production, nonferrous metal alloys, and electronic semiconductor manufacturing. Inorganic arsenic is also found in coke oven emissions associated with the smelter industry. [|[14]]

Occupational exposure to arsenic may occur with copper or lead smelting and wood treatment, among workers involved in the production or application of pesticides containing organic arsenicals. Humans are exposed to arsenic through air, drinking water, and food (meat, fish, and poultry); poultry is usually the largest source of food-based arsenic ingestion due to usage of certain antibiotics in chicken feed. Arsenic was also found in wine if arsenic pesticides are used in the vineyard. Arsenic is well absorbed by oral and inhalation routes, widely distributed and excreted in urine; most of a single, low-level dose is excreted within a few days after consuming any form of inorganic arsenic. Remains of arsenic in nails (which show as white spots and lines) and hair can be detected years after the exposure.

Food
China is the only country to have set a standard for arsenic limits in food (0.15 ppb), as levels in rice exceed those in water. It has been found that rice is particularly susceptible to arsenic poisoning. Rice grown in US has an average 260 ppb of arsenic according to a study.


 * Symbol:** As **Atomic Number:** 33 **Atomic Mass:** 74.9216 amu **Melting Point:** 817.0 °C (1090.15 K, 1502.6 °F) **Boiling Point:** 613.0 °C (886.15 K, 1135.4 °F) **Number of Protons/Electrons:** 33 **Number of Neutrons:** 42 **Classification:** Metalloid **Crystal Structure:** Rhombohedral **Density @ 293 K:** 5.72 g/cm3 **Color:** Gray

Atomic Structure

 * [[image:http://www.chemicalelements.com/bohr/b0033.gif width="277" height="275"]] ||  || **Number of Energy Levels:** 4
 * First Energy Level:** **Second Energy Level:** **Third Energy Level:** **Fourth Energy Level:** ||

Isotopes

 * ** Isotope ** || ** Half Life ** ||
 * As-71 || 2.7 days ||
 * As-72 || 26.0 hours ||
 * As-73 || 80.3 days ||
 * As-74 || 17.8 days ||
 * As-75 || Stable ||
 * As-76 || 26.3 hours ||
 * As-77 || 39.0 hours ||
 * As-79 || 9.0 minutes ||

Facts

 * Date of Discovery:** Known to the ancients **Discoverer:** Unknown **Name Origin:** From the Greek word //arsenikos// and the Latin word //arsenicum// **Uses:** Poison, conducts electricity, semiconductors **Obtained From:** mispickel

Treatment
Treatment of chronic arsenic poisoning is easily accomplished. British anti-lewisite ( [|dimercaprol] ) is prescribed in dosages of 5 mg/kg up to 300 mg each 4 hours for the first day. Then administer the same dosage each 6 hours for the second day. Then prescribe this dosage each 8 hours for eight additional days.However the Agency for Toxic Substances and Disease Registry (ATSDR) states that the long-term effects of arsenic exposure cannot be predicted. Blood, urine, hair, and nails may be tested for arsenic; however, these tests cannot foresee possible health outcomes from the exposure. Excretion occurs in the urine and long-term exposure to arsenic has been linked to bladder and kidney cancer in addition to cancer of the liver, prostate, skin, lungs and nasal cavity.

Exposure risks and remediation
Occupational exposure and arsenic poisoning may occur in persons working in industries involving the use of inorganic arsenic and its compounds, such as wood preservation, glass production, nonferrous metal alloys, and electronic semiconductor manufacturing. Inorganic arsenic is also found in coke oven emissions associated with the smelter industry. The ability of arsenic to undergo redox conversion between As(III) and As(V) makes its availability in the environment more abundant. According to Croal, Gralnick, Malasarn and Newman, "[the] understanding [of] what stimulates As(III) oxidation and/or limits As(V) reduction is relevant for bioremediation of contaminated sites (Croal). The study of chemolithoautotrophic As(III) oxidizers and the heterotrophic As(V) reducers can help the understanding of the oxidation and/or reduction of arsenic.

Arsenic in Drinking Water: Arsenic is a semi-metal element in the periodic table. It is odorless and tasteless. It enters drinking water supplies from natural deposits in the earth or from agricultural and industrial practices.

Non-cancer effects can include the following: thickening and discoloration of the skin, stomach pain, nausea, vomiting; diarrhea; numbness in hands and feet; partial paralysis; and blindness. Arsenic has been linked to cancer of the bladder, lungs, skin, kidney, nasal passages, liver, and prostate.

EPA has set the arsenic standard for drinking water at .010 parts per million (10 parts per billion) to protect consumers served by public water systems from the effects of long-term, chronic exposure to arsenic. Water systems must comply with this standard by January 23, 2006, providing additional protection to an estimated 13 million Americans.