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Names | |
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IUPAC name Sodium hydrogen methylarsonate | |
Other names Monosodium methyl arsenate; sodium methylarsonate; monosodium methane arsonate; methyl arsonic acid monosodium salt; EPA Pesticide Chemical Code 013803 | |
Identifiers | |
3D model (JSmol) | |
Abbreviations | MSMA |
ChemSpider | |
ECHA InfoCard | 100.016.815 |
PubChem CID | |
UNII | |
CompTox Dashboard (EPA) | |
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Properties | |
CH4AsNaO3 | |
Molar mass | 161.95 g/mol |
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa). |
Monosodium methyl arsenate (MSMA) is an arsenic-based herbicide. It is an organo-arsenate; less toxic than the inorganic form of arsenates. However, the EPA states that all forms of arsenic are a serious risk to human health and the United States' Agency for Toxic Substances and Disease Registry ranked arsenic as number 1 in its 2001 Priority List of Hazardous Substances at Superfund sites. [1]
Arsenic is classified as a Group-A carcinogen. [1] The EPA states that: [2]
Arsenate (AsV) is the oxidized form and occurs in well-aerated soils, whereas in chemically-reduced soil environments, arsenite (AsIII) is the prevalent As form. Although arsenite is more toxic than arsenate, arsenate can also have deleterious effects on humans, plants, and microorganisms. Arsenic-contaminated soils pose serious risk to human health. The EPA also states that, while contaminated soil poses a serious risk to health, arsenic frequently mobilizes from soils and other sources, ending up in water where it is even more of a toxicity issue.
Trade names include:
Arsenic is a chemical element; it has symbol As and atomic number 33. Arsenic occurs in many minerals, usually in combination with sulfur and metals, but also as a pure elemental crystal. Arsenic is a metalloid. It has various allotropes, but only the grey form, which has a metallic appearance, is important to industry.
Toxic waste is any unwanted material in all forms that can cause harm. Mostly generated by industry, consumer products like televisions, computers, and phones contain toxic chemicals that can pollute the air and contaminate soil and water. Disposing of such waste is a major public health issue.
The Agency for Toxic Substances and Disease Registry (ATSDR) is a federal public health agency within the United States Department of Health and Human Services. The agency focuses on minimizing human health risks associated with exposure to hazardous substances. It works closely with other federal, state, and local agencies; tribal governments; local communities; and healthcare providers. Its mission is to "Serve the public through responsive public health actions to promote healthy and safe environments and prevent harmful exposures." ATSDR was created as an advisory, nonregulatory agency by the Superfund legislation and was formally organized in 1985.
Superfund is a United States federal environmental remediation program established by the Comprehensive Environmental Response, Compensation, and Liability Act of 1980 (CERCLA). The program is administered by the Environmental Protection Agency (EPA). The program is designed to investigate and cleanup sites contaminated with hazardous substances. Sites managed under this program are referred to as Superfund sites. There are 40,000 federal Superfund sites across the country, and approximately 1,300 of those sites have been listed on the National Priorities List (NPL). Sites on the NPL are considered the most highly contaminated and undergo longer-term remedial investigation and remedial action (cleanups).
An environmental hazard is a substance, state or event which has the potential to threaten the surrounding natural environment or adversely affect people's health, including pollution and natural disasters such as storms and earthquakes. It can include any single or combination of toxic chemical, biological, or physical agents in the environment, resulting from human activities or natural processes, that may impact the health of exposed subjects, including pollutants such as heavy metals, pesticides, biological contaminants, toxic waste, industrial and home chemicals.
The National Priorities List (NPL) is the priority list of hazardous waste sites in the United States eligible for long-term remedial investigation and remedial action (cleanup) financed under the federal Superfund program. Environmental Protection Agency (EPA) regulations outline a formal process for assessing hazardous waste sites and placing them on the NPL. The NPL is intended primarily to guide EPA in determining which sites are so contaminated as to warrant further investigation and significant cleanup.
Cacodylic acid is an organoarsenic compound with the formula (CH3)2AsO2H. With the formula R2As(O)OH, it is the simplest of the arsinic acids. It is a colorless solid that is soluble in water.
Chromated copper arsenate (CCA) is a wood preservative containing compounds of chromium, copper, and arsenic, in various proportions. It is used to impregnate timber and other wood products, especially those intended for outdoor use, in order to protect them from attack by microbes and insects. Like other copper-based wood preservatives, it imparts a greenish tint to treated timber.
Munisport Landfill is a closed landfill located in North Miami, Florida adjacent to a low-income community, a regional campus of Florida International University, Oleta River State Park, and estuarine Biscayne Bay.
The Brio Superfund site is a former industrial location in Harris County, Texas at the intersection of Beamer Road and Dixie Farm Road, about 16 miles (26 km) southeast of downtown Houston, and adjacent to the Dixie Oil Processors Superfund site. It is a federal Superfund site, although it was deleted from the National Priorities List in December 2006. A neighboring residential subdivision called South Bend, now abandoned, was located along and north of the northern boundary of Brio North. The former South Bend neighborhood consisted of about 670 homes, an elementary school, and a Little League baseball field. Documents pertaining to the Brio Superfund site are located at the San Jacinto College South Campus Library, which houses Brio Site Repository Documents, U.S. Environmental Protection Agency (EPA) Administrative Records, and documents concerning the adjoining Dixie Oil Processors site.
Disodium methyl arsenate (DSMA) is the organoarsenic compound with the formula CH3AsO3Na2. It is a colorless, water-soluble solid derived from methanearsonic acid. It is used as a herbicide. Tradenames include Metharsinat, Arrhenal, Disomear, Metharsan, Stenosine, Tonarsan, Tonarsin, Arsinyl, Arsynal, and Diarsen.
The Omega Chemical Corporation was a refrigerant and solvent recycling company that operated from 1976 to 1991 in Whittier, California. Due to improper waste handling and removal, the soil and groundwater beneath the property became contaminated and the area is now referred to as the Omega Chemical Superfund Site. Cleanup of the site began in 1995 with the removal of hazardous waste receptacles and a multimillion-dollar soil vaporization detoxifying system.
The Waste Disposal Inc. Superfund site is an oil-related contaminated site in the highly industrialized city of Santa Fe Springs in Los Angeles County, California. It is approximately 38 acres (15 ha), with St Paul's high school immediately adjacent to the northeast corner of the site. Approximately 15,000 residents of Santa Fe Springs obtain drinking water from wells within three miles (4.8 km) of the site.
Arsenate-reducing bacteria are bacteria which reduce arsenates. Arsenate-reducing bacteria are ubiquitous in arsenic-contaminated groundwater (aqueous environment). Arsenates are salts or esters of arsenic acid (H3AsO4), consisting of the ion AsO43−. They are moderate oxidizers that can be reduced to arsenites and to arsine. Arsenate can serve as a respiratory electron acceptor for oxidation of organic substrates and H2S or H2. Arsenates occur naturally in minerals such as adamite, alarsite, legrandite, and erythrite, and as hydrated or anhydrous arsenates. Arsenates are similar to phosphates since arsenic (As) and phosphorus (P) occur in group 15 (or VA) of the periodic table. Unlike phosphates, arsenates are not readily lost from minerals due to weathering. They are the predominant form of inorganic arsenic in aqueous aerobic environments. On the other hand, arsenite is more common in anaerobic environments, more mobile, and more toxic than arsenate. Arsenite is 25–60 times more toxic and more mobile than arsenate under most environmental conditions. Arsenate can lead to poisoning, since it can replace inorganic phosphate in the glyceraldehyde-3-phosphate --> 1,3-biphosphoglycerate step of glycolysis, producing 1-arseno-3-phosphoglycerate instead. Although glycolysis continues, 1 ATP molecule is lost. Thus, arsenate is toxic due to its ability to uncouple glycolysis. Arsenate can also inhibit pyruvate conversion into acetyl-CoA, thereby blocking the TCA cycle, resulting in additional loss of ATP.
Groundwater pollution occurs when pollutants are released to the ground and make their way into groundwater. This type of water pollution can also occur naturally due to the presence of a minor and unwanted constituent, contaminant, or impurity in the groundwater, in which case it is more likely referred to as contamination rather than pollution. Groundwater pollution can occur from on-site sanitation systems, landfill leachate, effluent from wastewater treatment plants, leaking sewers, petrol filling stations, hydraulic fracturing (fracking) or from over application of fertilizers in agriculture. Pollution can also occur from naturally occurring contaminants, such as arsenic or fluoride. Using polluted groundwater causes hazards to public health through poisoning or the spread of disease.
Emmell's Septic Landfill (ESL) is located at 128 Zurich Ave, Galloway Township, New Jersey and takes up about 38 acres of space. The landfill was in operation from 1967 until 1979. ESL disposed of liquid and solid waste including many chemicals such as volatile organic compounds (VOCs), Polychlorinated Biphenyls (PCBs), Trichloroethene and Vinyl chloride which all had their own effect on the environment and community. These chemicals affected the groundwater required millions of dollars to reconstruct the groundwater pathways and provide clean water to residents. The landfill holds a Hazardous Ranking Score of a 50/100, qualifying for the Superfund National Priority List. In August 1999, the state acknowledged the site's contamination and held town meetings and provided research upon the site such as groundwater samples. In July 1997, a sitewide investigation was called upon by the United States Environmental Protection Agency. In total the clean up was estimated to cost $5 million to fund this superfund site, and a grant of $3.9 million was given by the Federal Government under the Recovery Act Funding (Previti). Today, the project is still ongoing however, greatly improved since the landfill was discovered.
The Horseshoe Road Complex Superfund Site in Sayreville, New Jersey is a 12-acre property located near the Raritan River. The industrial site has been out of operation since the early 1980s after a fire revealed 70 drums containing silver cyanide, ethyl acetate, and acetonitrile. The drums caught the attention of the Environmental Protection Agency (EPA) and by 1995 the Horseshoe Road Complex was on the National Priorities List. The site had three areas consisting of the Atlantic Development Corporation (ADC), Horseshoe Road Drum Dump, and Sayreville Pesticide Dump. The neighboring Atlantic Resources Corporation, the location for precious metal recovery, is addressed with the Horseshoe Road Complex (HRC) site due to the intermixing of chemical contamination. The on-site contamination is not an immediate threat to the surrounding community, although prolonged or repeated exposure to the site itself, will result in health effects. The HRC Superfund site is now in its final steps of cleanup in accordance to the EPA's plan.
The Orange Valley Regional Groundwater Superfund site is a group of wells in Orange and West Orange, two municipalities in Essex County, New Jersey, United States. The groundwater in the public wells are contaminated with the hazardous chemicals of Trichloroethylene (TCE), Dichloroethene (DCE), Tetrachloroethylene (Perchloroethene), 1,1-Dichloroethene (1,1-DCE), and 1,2-Dichloroethene (1,2-DCE). These chemicals pose a huge risk to the towns nearby population, as the wells are a source of public drinking water. In March 2012, the site was added to the National Priorities List (NPL) of the United States Environmental Protection Agency (EPA) Superfund site list.
Price Landfill is a 26-acre site located in Pleasantville, Egg Harbor Township, Atlantic County, New Jersey. Price Landfill is also known as Price Sanitary Landfill, Prices Pit, Price Landfill No.1 and Price Chemical Dump. The United States Environmental Protection Agency (USEPA) added Price Landfill to the Superfund National Priorities List on September 20, 1983, because of the hazardous chemicals found on the site and in the groundwater. The site was originally owned by Mr. Charles Price and was used to mine sand and gravel, which was shut down in 1968. The site was then turned into a private landfill in 1969 and then a commercial solid waste landfill in 1971. At this point the landfill was used to dispose of liquid waste by companies, specifically Atlantic City Electric Company. The liquid waste consisted of industrial chemicals, oils and greases/sludges, septic tank and sewer wastes, which were disposed on the site for 8 years, ending altogether in 1976, but in the meantime, having contaminated the groundwater, soil, air, and nearby creeks, specifically Absecon Creek. Chemicals dumped on the site are believed to be 1,2-Dichloroethane, arsenic, benzene, chloroform, lead, and vinyl chloride, all of which contaminated the groundwater, soil, air, and nearby creeks. The USEPA originally got involved in 1982 by beginning to correct the damage. Currently the USEPA states that they are continuing to monitor and treat the groundwater and land, and that hazards to humans are controlled.
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.