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Water Contaminant Descriptions:
Lead: as described by Wikipedia, the free encyclopedia!
Lead (IPA: /lɛd/) is a chemical element in the periodic table that has the symbol Pb (Latin: plumbum) and atomic number 82. A soft, heavy, toxic and malleable poor metal, lead is bluish white when freshly cut but tarnishes to dull gray when exposed to air. Lead is used in building construction, lead-acid batteries, bullets and shot, and is part of solder, pewter, and fusible alloys. Lead has the highest atomic number of all stable elements - although the next element, bismuth, has a half life so long it can be considered stable. Like mercury, another heavy metal, lead is a potent neurotoxin which accumulates in soft tissues and bone over time.
Mecury: as described by Wikipedia, the free encyclopedia!
Mercury (IPA: /ˈmɜːkjəˌɹi/), also called quicksilver, is a chemical element in the periodic table that has the symbol Hg (Latinized Greek: hydrargyrum, meaning watery or liquid silver) and atomic number 80. A heavy, silvery transition metal, mercury is one of five elements that are liquid at or near standard room temperature and pressure[1] (the others are the metals caesium, francium, and gallium, and the nonmetal bromine). Mercury is used in thermometers, barometers and other scientific apparatus, although the use of mercury in thermometers has been largely phased out in clinical and scientific environments (in favor of alcohol-filled, digital or thermistor-based replacements) due to concerns about the element's toxicity. Mercury is still used in dental amalgam. Mercury is mostly obtained by reduction from the mineral cinnabar. Mercury, like lead, is a neurotoxin, and elevated blood mercury levels have led to retardation and deformities in children.
Asbestos: as described by Wikipedia, the free encyclopedia!
Asbestos (a misapplication of Latin: asbestos "quicklime" from Greek ἄσβεστος: a, "not" and sbestos, "extinguishable") describes any of a group of minerals that can be fibrous, many of which are metamorphic and are hydrous magnesium silicates. These minerals, together with their occurrences, uses, and associated hazards, have been discussed in detail by Guthrie and Mossman (1993).
The name is derived for its historical use in lamp wicks; the resistance of asbestos to fire has long been exploited for a variety of purposes. Asbestos was used in fabrics such as Egyptian burial cloths and Charlemagne's tablecloth (which according to legend, he threw in a fire to clean). Asbestos occurs naturally in many forms (see below); it is mined from metamorphic rocks.
When asbestos is used for its resistance to fire or heat, the fibers are often mixed with cement or woven into fabric or mats. Asbestos is used in brake shoes and gaskets for its heat resistance, and in the past was used on electric oven and hotplate wiring for its electrical insulation at elevated temperature, and in buildings for its flame-retardant and insulating properties, tensile strength, flexibility, and resistance to chemicals. The inhalation of some kinds of asbestos fibers, however, can cause a number of serious illnesses, including cancer. Many uses of asbestos are banned in multiple countries.
Main Types of Cyst:
1)Giardia: as described by Wikipedia, the free encyclopedia!
Giardia lamblia (formerly also Lamblia intestinalis and also known as Giardia duodenalis and Giardia intestinalis) is a flagellated protozoan parasite that infects the gastrointestinal tract and causes giardiasis.
Giardia affects humans. It is also one of the most common parasites infecting cats. Mammalian hosts also include cows, beavers, deer, dogs and lambs.
Infection causes giardiasis, a type of gastroenteritis that manifests itself with severe diarrhea and abdominal cramps. Other symptoms can include bloating, flatulence, fatigue, nausea, vomiting and weight loss. In some patients, vomiting or nausea is the major symptom. The symptoms usually manifest themselves about seven to ten days after ingestion. Giardia is a major cause of intestinal disease worldwide and the most frequent non-bacterial cause of diarrhea in North America. Nonetheless, the basic biology of this parasite is poorly understood.
2)Cryptosporidium: as described by Wikipedia, the free encyclopedia!
Cryptosporidium is a protozoan pathogen of the Phylum Apicomplexa and causes a diarrheal illness called cryptosporidiosis. Other apicomplexan pathogens include the malaria parasite Plasmodium, and Toxoplasma, the causative agent of toxoplasmosis. Unlike Plasmodium, which transmits via a mosquito vector, Cryptosporidium does not utilize an insect vector and is capable of completing its life cycle within a single host, resulting in cyst stages which are excreted in feces and are capable of transmission to a new host.
A number of species of Cryptosporidium infect mammals. In humans, the main causes of disease are C. parvum and C. hominis (previously C. parvum genotype 1). C. canis, C. felis, C. meleagridis, and C. muris can also cause disease in humans.
Cryptosporidiosis is typically an acute short-term infection but can become severe and non-resolving in children and immunocompromised individuals such as AIDS patients. The parasite is transmitted by environmentally hardy cysts (oocysts) that, once ingested, excyst in the small intestine and result in an infection of intestinal epithelial tissue. The genome of Cryptosporidium parvum was sequenced in 2004 and was found to be unusual amongst Eukaryotes in that the mitochondria seem not to contain DNA [2].
Most treatment plants that take raw water from rivers, lakes, and reservoirs for public drinking water production use conventional filtration technologies. This involves a series of processes including coagulation, flocculation, sedimentation, and filtration. Direct filtration, which is typically used to treat water with low particulate levels, includes coagulation and filtration but not sedimentation. Other common filtration processes are slow sand, diatomaceous earth, membranes, and bag and cartridge filters. Conventional, direct, slow sand and diatomaceous earth technologies will remove 99% of Cryptosporidium. Membranes and bag and cartridge filters remove Cryptosporidium on a product-specific basis. With the proper concentrations and contact time, Cryptosporidium inactivation will occur with chlorine dioxide and ozone treatment. Additionally, ultraviolet light treatment at relatively low doses will inactivate Cryptosporidium.
Atrazine: as described by Wikipedia, the free encyclopedia!
Atrazine, 2-chloro-4-(ethylamine)-6-(isopropylamine)-s-triazine, is an s-triazine-ring herbicide that is used globally to stop pre- and post-emergence broadleaf and grassy weeds in major crops. Atrazine binds to the plastoquinone-binding protein in photosystem II, inhibiting electron transport. Atrazine is one of the most widely used herbicides and according to the Environmental Protection Agency (EPA) the U.S. used 77 million lb of Atrazine in 2003. In 2003, EPA classified the herbicide as "not likely" to cause cancer in humans, stating it did "not find any results among the available studies that would lead us to conclude that a potential cancer risk is likely from exposure to atrazine." After a 10-year science review, EPA recommended atrazine's re-registration in October 2003.
Lindane: as described by Wikipedia, the free encyclopedia!
Lindane is an insecticide, also known as gamma-hexachlorocyclohexane (HCH) and benzene hexachloride (BHC). It has an LD50 of 88 mg/kg, and is suspected of being a carcinogen. Its method of action is via interfering with the GABAa receptor/Cl- channel. It has been used in agriculture and in pharmaceutical products for the treatment of headlice and scabies.
Lindane is banned in 52 countries, and under review for addition to the Stockholm Convention On Persistent Organic Pollutants.[1] In the U.S. the EPA recently banned all agricultural uses of lindane, but the FDA still allows lindane to be used in pharmaceuticals products for the treatment of headlice and scabies. California has banned all uses of lindane, and there is a bill in the New York State Assembly and Senate to ban its use in headlice products and limit its use on scabies. Its use is restricted or banned in most of Europe and many developing countries.[2] Mexico is the next of many nations who are banning lindane. Larger than the issue of toxicity of lindane itself, the bans also have to do with the other isomers of HCH produced as by-products, which have little or no use. These isomers were stockpiled in open heaps by lindane producers in the 1940s and 1950s leading to severe ground and water contamination.
2,4-Dichlorophenoxyacetic acid: as described by Wikipedia, the free encyclopedia!
2,4-Dichlorophenoxyacetic acid (2,4-D) is a common systemic herbicide used in the control of broadleaf weeds. It is the third-most widely used herbicide in North America and the most widely used herbicide in the world.
2,4-D was developed during World War II by a British team at Rothamsted Experimental Station, under the leadership of Judah Hirsch Quastel, aiming to increase crop yields for a nation at war. For a more complete history on the development of phenoxy herbicides, see J.R. Troyer (2001)[1]. When it was commercially released in 1946, it became the first successful selective herbicide and allowed for greatly enhanced weed control in wheat, maize (corn), rice, and similar cereal grass crop, because it only kills dicots, leaving behind monocots.
2,4-D is sold in various formulations under a wide variety of brand names. It continues to be used for its low cost, despite the availability of more selective, more effective, and less toxic products.
2,4-D is a synthetic auxin, which is a class of plant growth regulators.
Chlorine: as described by Wikipedia, the free encyclopedia!
Chlorine (IPA: /ˈklɔːriːn/, Greek: χλωρóς chloros, meaning "pale green"), is the chemical element with atomic number 17 and symbol Cl. It is a halogen, found in the periodic table in group 17. As the chloride ion, which is part of common salt and other compounds, it is abundant in nature and necessary to most forms of life, including humans. In its elemental form under standard conditions, it is a pale green gas about 2.5 times as dense as air. It has a disagreeable suffocating odor and is poisonous. Chlorine is a powerful oxidant and is used in bleaching and disinfectants. It is also used in swimming pools to keep them clean.
Chlorine is an important chemical for some processes of water purification, in disinfectants, and in bleach. Ozone can also be used for killing bacteria, and is preferred by many municipal drinking water systems because ozone does not form organochlorine compounds and does not remain in the water after treatment. Ozone is also more reactive and will kill organisms that chlorine will not.
Chlorine is also used widely in the manufacture of many every-day items, or to purify water in various forms. Used (in the form of hypochlorous acid) to kill bacteria and other microbes in drinking water supplies and swimming pools. However, in most non-commercial swimming pools chlorine itself is not used, but rather sodium hypochlorite (household bleach), a compound of chlorine with sodium and oxygen. Calcium hypochlorite is also used as a cheaper alternative. Even small water supplies are now routinely chlorinated.[5] (See also chlorination) Used widely in paper product production, antiseptic, dyestuffs, food, insecticides, paints, petroleum products, plastics, medicines, textiles, solvents, and many other consumer products.
Turbidity: as described by Wikipedia, the free encyclopedia!
Turbidity is a cloudiness or haziness of water (or other fluid) caused by individual particles (suspended solids) that are generally invisible to the naked eye, thus being much like smoke in air. Turbidity is generally caused by phytoplankton. Measurement of turbidity is a key test of water quality. The higher the turbidity, the higher the risk of the drinkers developing gastrointestinal diseases, especially for immune-compromised people, because contaminants like virus or bacteria can become attached to the suspended solid. High water turbidity is the leading cause of gastrointestinal cancer in the United States.
Particulates: as described by Wikipedia, the free encyclopedia!
Particulates, alternatively referred to as particulate matter (PM), aerosols or fine particles, are tiny particles of solid or liquid suspended in a gas. They range in size from less than 10 nanometres to more than 100 micrometres in diameter. The notation PM10 is used to describe particles of 10 micrometres or less; other numeric values may also be used. This range of sizes represent scales from a gathering of a few molecules to the size where the particles no longer can be carried by the gas. Sources of particulate matter can be anthropogenic or natural. Anthropogenic sources in Northern Europe in the main stem from food production thus during episodes of poor air quality a noticable weight gain can be observed within the population causing major health concerns.
Sediment: as described by Wikipedia, the free encyclopedia!
Sediment is any particulate matter that can be transported by fluid flow and which eventually is deposited as a layer of solid particles on the bed or bottom of a body of water or other liquid. Sedimentation is the deposition by settling of a suspended material.
Sediments are also transported by wind (eolian) and glaciers. Desert sand dunes and loess are examples of aeolian transport and deposition. Glacial moraine deposits and till are ice transported sediments. Simple gravitational collapse also creates sediments such as talus and mountainslide deposits as well as karst collapse features. Each sediment type has different settling velocities, depending on size, volume, density, and shape.
Tetrachloroethylene: as described by Wikipedia, the free encyclopedia!
Tetrachloroethylene Cl2C=CCl2 is a manufactured chemical compound that is widely used for the dry cleaning of fabrics and for metal-degreasing. It is also used to make other chemicals and is used in some consumer products.
Other names for tetrachloroethylene include perchloroethylene, perc, PCE, and tetrachloroethene. It is a nonflammable liquid at room temperature. It evaporates easily into the air and has a sharp, sweet odor. Most people can smell tetrachloroethylene when it is present in the air at a concentration of 1 part per million (1 ppm), although some can smell it at even lower levels.
Most applications of tetrachloroethylene use it for its solvent properties. Most organic materials dissolve in tetrachloroethylene. It is the most widely used solvent in dry cleaning. It is also used to degrease metal parts in the automotive and other metalworking industries. It appears in a few consumer products including paint strippers and spot removers.
In the early 20th century, tetrachloroethylene was the most effective available treatment for hookworm.
Tetrachloroethylene is also extensively used as an intermediate in the manufacture of refrigerants such as HFC-134a.
MTBE: as described by Wikipedia, the free encyclopedia!
Methyl tert-butyl ether (MTBE) is a chemical compound with molecular formula C5H12O. MTBE is a volatile, flammable and colorless liquid that is relatively soluble in water. MTBE has a typical odour reminiscent of diethyl ether, leading to unpleasant taste and odor in water. MTBE is used in organic chemistry as a cheap solvent with properties comparable to diethyl ether but with a higher boiling point and lower solubility in water. It is also used medically to dissolve gallstones.
Fluoride: as described by Wikipedia, the free encyclopedia!
Fluoride is the ionic form of fluorine. Fluorides are organic and inorganic compounds containing the element fluorine. As a halogen, fluorine forms a monovalent ion (−1 charge). Fluoride forms a binary compound with another element or radical. Examples of fluoride compounds include hydrofluoric acid (HF), sodium fluoride (NaF) and calcium fluoride (CaF2), and uranium hexafluoride (UF6).
Fluoride containing compounds such as sodium fluoride, calcium fluoride, and sodium monofluorophosphate are commonly added to toothpaste, drinking water, prescribed treatments, and other commercially available oral hygiene products because fluoride strengthens the tooth enamel. Originally, sodium fluoride was used to fluoridate water; however, hexafluorosilicic acid (H2SiF6) and its salt sodium hexafluorosilicate (Na2SiF6) are more commonly used, especially in the United States.
Some studies suggest that fluoridation is associated with a median decline in the number of children with caries of 12.5%, and a median decline of 2.25 teeth with caries. [3] The fluoridation of water is not without critics, however.
Ethylbenzene: as described by Wikipedia, the free encyclopedia!
Ethylbenzene is an organic chemical compound which is an aromatic hydrocarbon. Its major use is in the petrochemical industry as an intermediate compound for the production of styrene, which in turn is used for making polystyrene, a commonly used plastic material. Although often present in small amounts in crude oil, ethylbenzene is produced in bulk quantities by combining the petrochemicals benzene and ethylene in an acidically-catalyzed chemical reaction. Catalytic dehydrogenation of the ethylbenzene then gives hydrogen gas and styrene, which is vinylbenzene.
Endrin: as described by Wikipedia, the free encyclopedia!
Endrin is a cyclodiene insecticide used on cotton, maize, and rice. It also acts as an avicide. As a rodenticide, it is used to control mice and voles. It is a solid, cream to light tan to white, almost odorless substance. It melts and decomposes at 200 °C. It is moderately soluble in benzene and acetone, slightly soluble in alcohols, alkanes, and xylene, and almost insoluble in water. It is also known as Mendrin, and Compound 269.
The use of endrin is now banned in many countries.
The majority of use (about 80%) was as a spray to control insect pests of cotton. It was also used on rice, to some extent on sugar cane, in a limited way on grain crops and sugar beets, and in Australia on tobacco and cole crops. It was occasionally used in orchards as a control of rodents, where it is sprayed on the ground under the trees in autumn or spring, often as a solution in mineral oil. As a seed treatment, it was used for cotton seed in the United States, and for beans seeds in Australia.
Dichlorobenzene: as described by Wikipedia, the free encyclopedia!
1,2-Dichlorobenzene, or ortho-dichlorobenzene, is an organic compound used primarily as a high-boiling solvent. It is a benzene derivative with two chlorine atoms substituted at adjacent positions. It is a colorless liquid that is insoluble in water, but is miscible with ethanol, diethyl ether and benzene.
1,2-Dichlorobenzene is used as a solvent for waxes, gums, resins, tars, rubbers, and oils. It is a preferred solvent in some chemical reactions involving fullerenes. It is also used as a degreasing agent for metals, leather and wool.
1,2-Dichlorobenzene is an insecticide for termites and locust borers.
Alachlor: as described by Wikipedia, the free encyclopedia!
Alachlor is an herbicide, marketed under the trade name Lasso, used mainly to control weeds in corn and soybean fields. EPA has found alachlor to potentially cause the following health effects when people are exposed to it at levels above the maximum contaminant level (MCL) for relatively short periods of time: slight skin and eye irritation.
Alachlor has the potential to cause the following effects from a lifetime exposure at levels above the MCL: damage to liver, kidney, spleen; lining of nose and eyelids; cancer.[1]
Benzene: as described by Wikipedia, the free encyclopedia!
Benzene, also known as benzol, is an organic chemical compound with the formula C6H6. It is sometimes abbreviated Ph-H. Benzene is a colorless and flammable liquid with a sweet smell and a relatively high melting point. It is carcinogenic and its use as additive in gasoline is now limited, but it is an important industrial solvent and precursor in the production of drugs, plastics, synthetic rubber, and dyes. Benzene is a natural constituent of crude oil, but it is usually synthesized from other compounds present in petroleum. Benzene is an aromatic hydrocarbon and the second [n]-annulene ([6]-annulene).
Carbofuran: as described by Wikipedia, the free encyclopedia!
Carbofuran is one of the most toxic carbamate pesticides. It is marketed under the trade names Furadan, by FMC Corporation and Curater, among several others. It is used to control insects in a wide variety of field crops, including potatoes, corn and soybeans. It is a systemic insecticide, which means that the plant absorbs it through the roots, and from here the plant distributes it throughout its organs (mainly vessels, stems and leaves; not the fruits), where insecticidal concentrations are attained. Carbofuran also has contact activity against pests.
It has one of the highest acute toxicities to humans of any insecticide widely used on field crops (more toxic are only aldicarb and parathion). A quarter teaspoon ( 1 mL) can be fatal. Most carbofuran is applied by commercial applicators using closed systems with engineered controls, so that there is no exposure to the chemical through pouring or measuring. Toxic effects are due to its activity as a cholinesterase inhibitor (it is thus considered a neurotoxic pesticide).
Carbofuran is also known to be highly toxic to birds. In its granular form, a single grain will kill a bird. Birds often eat numerous grains of the pesticide, mistaking them for seeds, and then die shortly thereafter. Before it was banned by USEPA in 1991 ([1]), granular carbofuran was blamed for millions of bird deaths per year. The liquid version of the pesticide is less hazardous to birds since they are not as likely to ingest it directly, but it is still very hazardous.
Carbofuran usage has increased in recent years because it is one of the few insecticides effective on soybean aphids, which have expanded their range since 2002 to include most soybean-growing regions of the U.S.
Chlorobenzene: as described by Wikipedia, the free encyclopedia!
Chlorobenzene has been used in the manufacture of certain pesticides, most notably DDT by reaction with chloral (trichloroacetaldehyde). It once found use in the production of phenol. Today the major use of chlorobenzene is as an intermediate in the production of nitrochlorobenzenes and diphenyl oxide, which are important in the production of commodities such as herbicides, dyestuffs, and rubber. Chlorobenzene is also used as a high-boiling solvent in organic synthesis as well as many industrial applications.
Toxaphene: as described by Wikipedia, the free encyclopedia!
Toxaphene (CAS 8001-35-2) is an organic insecticide with the approximate empirical formula C10H10Cl8 and average molecular mass of 414. It is usually seen as a yellow to amber waxy solid, or in gas form. In 1990, it was banned for all uses in the United States. When inhaled or ingested, sufficient quantities of toxaphene can damage the lungs, nervous system, and kidneys, and may cause death.
Also called: camphechlor, chlorinated camphene, polychlorocamphene, chlorocamphene, octachlorocamphene
Trademarked name: Toxaphene, Strobane, Mellipax
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