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.
Toxicity is the degree to which a chemical substance or a particular mixture of substances can damage an organism. Toxicity can refer to the effect on a whole organism, such as an animal, bacterium, or plant, as well as the effect on a substructure of the organism, such as a cell (cytotoxicity) or an organ such as the liver (hepatotoxicity). By extension, the word may be metaphorically used to describe toxic effects on larger and more complex groups, such as the family unit or society at large. Sometimes the word is more or less synonymous with poisoning in everyday usage.
Chlordane, or chlordan, is an organochlorine compound that was used as a pesticide. It is a white solid. In the United States, chlordane was used for termite-treatment of approximately 30 million homes until it was banned in 1988. Chlordane was banned 10 years earlier for food crops like corn and citrus, and on lawns and domestic gardens.
Piperonyl butoxide (PBO) is a pale yellow to light brown liquid organic compound used as a synergist component of pesticide formulations. That is, despite having no pesticidal activity of its own, it enhances the potency of certain pesticides such as carbamates, pyrethrins, pyrethroids, and rotenone. It is a semisynthetic derivative of safrole.
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.
Atrazine is a chlorinated herbicide of the triazine class. It is used to prevent pre-emergence broadleaf weeds in crops such as maize (corn), soybean and sugarcane and on turf, such as golf courses and residential lawns. Atrazine's primary manufacturer is Syngenta and it is one of the most widely used herbicides in the United States, Canadian, and Australian agriculture. Its use was banned in the European Union in 2004, when the EU found groundwater levels exceeding the limits set by regulators, and Syngenta could not show that this could be prevented nor that these levels were safe.
Ethylmercury (sometimes ethyl mercury) is a cation composed of an organic CH3CH2- species (an ethyl group) bound to a mercury(II) centre, making it a type of organometallic cation, and giving it a chemical formula C2H5Hg+. The main source of ethylmercury is thimerosal.
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.
Hexavalent chromium (chromium(VI), Cr(VI), chromium 6) is chromium in any chemical compound that contains the element in the +6 oxidation state (thus hexavalent). Hexavalent chromium is key to all materials made from chromium. Approximately 136,000 tonnes (150,000 tons) of hexavalent chromium were produced in 1985. Hexavalent chromium compounds can be carcinogens (IARC Group 1), especially if airborne and inhaled where they can cause lung cancer.
Arsenic contamination of groundwater is a form of groundwater pollution which is often due to naturally occurring high concentrations of arsenic in deeper levels of groundwater. It is a high-profile problem due to the use of deep tube wells for water supply in the Ganges Delta, causing serious arsenic poisoning to large numbers of people. A 2007 study found that over 137 million people in more than 70 countries are probably affected by arsenic poisoning of drinking water. The problem became a serious health concern after mass poisoning of water in Bangladesh. Arsenic contamination of ground water is found in many countries throughout the world, including the US.
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.
Toxic equivalency factor (TEF) expresses the toxicity of dioxins, furans and PCBs in terms of the most toxic form of dioxin, 2,3,7,8-TCDD. The toxicity of the individual congeners may vary by orders of magnitude.
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.
Toxicodynamics, termed pharmacodynamics in pharmacology, describes the dynamic interactions of a toxicant with a biological target and its biological effects. A biological target, also known as the site of action, can be binding proteins, ion channels, DNA, or a variety of other receptors. When a toxicant enters an organism, it can interact with these receptors and produce structural or functional alterations. The mechanism of action of the toxicant, as determined by a toxicant’s chemical properties, will determine what receptors are targeted and the overall toxic effect at the cellular level and organismal level.
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.
Sharkey Landfill is a 90-acre property located in New Jersey along the Rockaway and Whippany rivers in Parsippany, New Jersey. Landfill operations began in 1945, and continued until September 1972, when large amounts of toluene, benzene, chloroform, dichloroethylene, and methylene chloride were found, all of which have are a hazard to human health causing cancer and organ failure. Sharkey Landfill was put on the National Priority List in 1983, and clean up operations ran until the site was deemed as not a threat in 2004.
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.
Ohio River Park is a Superfund Site located in Neville Island, Pennsylvania. Between the 1920s-1970s, the Site was used for municipal waste, pesticide manufacturing, coke sludge disposal, cement manufacturing disposal, and pesticide waste. In 1977, Neville Land Company donated the Site to Allegheny County who started developing the Site as a community park. In 1979, Allegheny County found various hazardous contaminants on the Site. On August 30, 1990, the Site was determined to be a Superfund Site due to VOCs, SVOCs, inorganics, and pesticides being present in the surface soil, subsurface soil, surface water, river sediment, and groundwater. Soil remediation began in February 1998 and ended in September 1999. Today, Ohio River Park has the Robert Morris University Island Sports Center and Coraopolis Bridge on top of it. Additionally, benzene continues to be monitored because it is still present in the Site's groundwater.
