Complete Water Contaminants Database

Synthetic volatile organic compound originally developed as a less toxic substitute for other chlorinated industrial chemicals. It is currently used as a solvent and cleaning agent, and was previously an ingredient in household cleaning products, glues, and aerosol sprays. It is readily volatile, thus all routes of exposure (ingestion, inhalation and dermal) are relevant if one is exposed via drinking water. It has been detected in both surface water and groundwater.

Synthetic volatile organic compound (VOC). It was formerly used as an industrial solvent, and to produce pesticides, bleaches, and paints, but currently has no known uses besides as an intermediate in the production of other chemicals. It is readily volatile, thus all routes of exposure (ingestion, inhalation and dermal) are relevant if one is exposed via drinking water. It has been detected in wastewater, drinking water, groundwater, and surface water near contaminated sites. It evaporates easily from surface water, so it is more likely to be detected in groundwater sources.

Synthetic volatile organic compound (VOC) employed primarily in producing vinylidene chloride, and is also used as a solvent

Synthetic volatile organic compound (VOC). It is primarily used in vinyl chloride production, a material used in PVC pipes, upholstery, and housewares; it is also used as a solvent and a gasoline additive. It evaporates easily from surface water, so it is more often found in groundwater sources. 1,2 Dichloroethane is readily volatile, thus all routes of exposure (ingestion, inhalation and dermal) are relevant if one is exposed via drinking water. Health effects associated with 1,2 dichloroethane in drinking water include liver and kidney toxicity and an increased risk of cancer.

1,2-Dichloropropane is a colorless liquid with a sweet odor. It is used as a solvent and in the production of other chemicals. It is a chlorinated hydrocarbon and is classified as a volatile organic compound (VOC).

Synthetic volatile organic chemical (VOC) used to make other chemicals. It has been used as a solvent to clean and degrease materials and to produce pesticides. It is readily volatile, thus all routes of exposure (ingestion, inhalation and dermal) are relevant if one is exposed via drinking water.

One of three trimethylbenzene isomers found naturally in coal tar and petroleum. It is a common component of C9 fraction, a common gasoline additive, and is used in solvents, paint thinners, dyes, paints, plastics, and pharmaceuticals. Trimethylbenzenes are readily volatile, so all routes of exposure (ingestion, inhalation and dermal) are relevant if one is exposed via drinking water. They are more often detected in groundwater than surface water because they easily vaporize when exposed to air. Health effects related to elevated exposure to trimethylbenzenes include nervous, respiratory, and blood system effects.

Volatile organic compound (VOC). It is a major component in pesticides used to control parasitic, microscopic worms called nematodes. It is readily volatile, thus all routes of exposure (ingestion, inhalation and dermal) are relevant if one is exposed via drinking water.

One of three trimethylbenzene isomers found naturally in coal tar and petroleum. It is commonly used in dyes, solvents, paint thinners, and plastics. Trimethylbenzenes are readily volatile, so all routes of exposure (ingestion, inhalation and dermal) are relevant if one is exposed via drinking water. They are more often detected in groundwater than surface water because they easily vaporize when exposed to air. Health effects related to elevated exposure to trimethylbenzenes include nervous, respiratory, and blood system effects.

1,4-Dioxane is a synthetic industrial chemical that is used as a solvent and in the production of other chemicals. It is a colorless liquid with a faint sweet odor and is miscible with water.

Part of a class of synthetic compounds known as polyfluoroalkyl substances (PFAS) widely used to make products more resistant to stains, water, and grease. For example, PFAS have been used in nonstick cookware, textiles, food packaging, electronics, cleaners, and many other consumer products.

Acremonium is a genus of filamentous fungi belonging to the family Hypocreaceae. Acremonium species occur naturally in the environment in areas with lots of moisture and places containing decaying organic matter, as well as in indoor environments with excessive moisture from things like water damage. Acremonium colonies grow slowly and turn from moist to powdery as they age. Colonies may appear white, gray, or pinkish in color. Acremonium species have been detected in groundwater, surface water, and treated drinking water. Certain fungi may collect and proliferate in biofilms throughout drinking water distribution systems, though there is limited evidence regarding Acremonium species in biofilms.

Organic compound and herbicide used to control weeds on croplands (including corn, soybeans, and peanuts) and non-agricultural areas

Alkalinity is a key measure of a water sample's general chemistry. Alkalinity measures the capacity of water to neutralize acids. Alkalinity is thus indicative of the stability of a water sample's pH upon the addition of acid; water with higher alkalinity will maintain a stable pH after the addition of more acid. Water with low alkalinity cannot buffer against such changes and can therefore become acidic and potentially corrosive to plumbing.The vast majority of alkalinity comes from dissolved carbonate and bicarbonate, though other compounds, like phosphates and borates, contribute minorly to alkalinity.

Alternaria is a genus of fungi that is commonly found in soil, air, and decaying plant material. It is known for its ability to produce allergens and mycotoxins, which can contaminate food and water supplies.

Naturally-occurring metal found in the Earth's crust with multiple industrial uses, including the construction of buildings and powerlines, and the manufacture of vehicles, consumer electronics, household appliances, and kitchenware. It is also frequently used in municipal water treatment to clarify water from lakes and reservoirs. Health effects of aluminum exposure are inconclusive but actively researched.

Metal most commonly used as a flame retardant and occasionally as solder in plumbing. High levels of antimony in drinking water are rare. However, antimony levels can be elevated if drinking water sources are exposed to industrial discharges, contaminated by wastewater, or potentially leachate from antimony-containing solder. Health protective levels of antimony in drinking water are based on animal studies that show long term exposure may result in adverse health effects, including liver damage and reduced longevity.

Naturally occurring element that has both inorganic and organic forms

Aspergillus flavus is a species of fungus that can produce aflatoxins, which are toxic compounds that can contaminate food and feed. It is commonly found in soil, decaying vegetation, and stored grains.

Aspergillus fumigatus is a species of fungus that is commonly found in the environment, particularly in soil and decaying organic matter. It is known for its ability to thrive in various conditions, including those that are nutrient-poor. This fungus can produce spores that are easily airborne, making it a common allergen and potential pathogen in humans.

Aspergillus nidulans is a species of fungus that is commonly found in soil and decaying organic matter. It is a filamentous fungus that can produce a variety of secondary metabolites, some of which may have toxic properties. This organism is known for its ability to thrive in various environmental conditions and can be a contaminant in food and water supplies.

Aspergillus niger is a species of fungus that is commonly found in soil and decaying plant matter. It is known for its ability to produce a variety of enzymes and organic acids, which can be beneficial in industrial applications, such as food processing and biotechnology. However, it can also be a contaminant in drinking water, particularly in areas with poor sanitation or agricultural runoff.

Aspergillus ochraceus is a species of fungus that is commonly found in soil, decaying vegetation, and various food products. It is known for producing ochratoxin A, a mycotoxin that can contaminate food and water supplies. This fungus thrives in warm and humid environments and can grow on a variety of substrates, including grains, nuts, and dried fruits.

Aspergillus species are a group of fungi that are commonly found in various environments, including soil, decaying vegetation, and indoor environments. They are known for their ability to produce a variety of secondary metabolites, some of which can be toxic to humans and animals. Aspergillus species can thrive in a wide range of conditions and are often associated with food spoilage and contamination.

Aspergillus versicolor is a species of fungus that is commonly found in indoor environments, particularly in damp or water-damaged buildings. It is known for its ability to grow on a variety of substrates, including wood, paper, and textiles. This mold can produce mycotoxins, which are toxic compounds that can pose health risks to humans.

Synthetic organic compound and part of a class of herbicides called triazines, which inhibit photosynthesis

Aureobasidium is a genus of fungi that is commonly found in soil, on plants, and in indoor environments. It is known for its ability to thrive in various conditions, including high humidity and low light. Aureobasidium species can produce dark pigmented spores and are often associated with the decay of organic matter.

Basidiomycetes are a group of fungi that include mushrooms, puffballs, and shelf fungi. They are characterized by their reproductive structures called basidia, which produce spores. These fungi play a crucial role in the ecosystem as decomposers, breaking down organic matter and recycling nutrients back into the soil.

Bentazon is a selective herbicide used to control broadleaf weeds and sedges in various crops. It works by inhibiting photosynthesis in target plants, leading to their death. Bentazon is a member of the benzothiadiazole class of chemicals and is known for its relatively low toxicity to mammals and birds.

Colorless liquid with a sweet odor that is used in the production of other chemicals, as an industrial solvent, and as an additive in gasoline. Benzene is a member of a class of chemicals called BTEX, which are among the most abundantly produced chemicals in the world, notably created and used in petroleum processing and the production of consumer goods. It is readily volatile, thus all routes of exposure (ingestion, inhalation and dermal) are relevant if one is exposed via drinking water. The EPA has determined that benzene is a known human carcinogen by all routes of exposure. It has various noncancer health impacts as well, including to the immune and hematological systems.

Chemical element and a member of a class of organic chemicals called polycyclic aromatic hydrocarbons (PAHs) that occur naturally in coal tar, petroleum, and crude oil. There are no known industrial uses for benzo(a)pyrene, but small amounts are used as a laboratory reagent for research.

Alkaline metal that occurs naturally in the earth's crust in minerals. It has many uses in the electronics, aerospace, and defense industries. Exposure to elevated beryllium levels in drinking water can occur when water sources are polluted by industrial activity. The EPA drinking water limits on beryllium are based on adverse gastrointestinal health effects seen in animal studies.

Bipolaris drechslera is a fungal pathogen that can contaminate water sources, particularly in agricultural areas. It is known for causing diseases in plants, particularly in crops such as barley and wheat. The fungus thrives in warm, moist environments and can produce spores that are easily dispersed by wind or water.

Synthetic organic chemical primarily used to promote plasticity and flexibility in man-made materials, including polyvinyl chloride food packaging

Member of a family of synthetic compounds called phthalates that are added to polyvinyl chloride (PVC), a chemical used to improve flexibility and durability in consumer products

Boron is an element that occurs naturally in the earth's crust as borate minerals. It can be found in food, consumer products and some water sources, including some bottled water and groundwater from highly mineralized aquifers. While evidence suggests it is likely an essential nutrient for human health, animal studies have shown that exposure to high levels of boron can cause adverse developmental and reproductive effects.

Botrytis is a genus of fungi that includes several species known for causing plant diseases, particularly in grapes and other fruits. It can thrive in moist conditions and is often associated with the decay of plant material.

Bromate is a chemical compound that can form in drinking water when bromide, a naturally occurring element, reacts with ozone during water treatment. It is a colorless, odorless, and tasteless compound that is soluble in water.

Bromochloroacetic acid is a chemical compound that is a derivative of acetic acid. It is used in various industrial applications and can be formed as a byproduct in the chlorination of drinking water. It is a colorless liquid that is soluble in water and has a pungent odor.

Member of trihalomethanes (THMs) that form in water treated with chlorine

Member of trihalomethanes (THMs) that form in water treated with chlorine

Heavy metal most often found in drinking water due to the corrosion of galvanized pipes. It has a variety of industrial uses, primarily as a component in batteries, pigments, coatings, and electroplating. It also occurs as a natural impurity in phosphate rocks, and is present in certain phosphate fertilizers as a result. Cadmium can accumulate in plants and organisms throughout the food chain from contaminated soil and water. Long-term exposure to excess cadmium may lead to kidney dysfunction, skeletal defects, and multiple types of cancer.

Organic compound, insecticide, and nematicide (worm-killer). It is used to prevent pests in agricultural crops, including spinach grown for seed, pine seedlings, cucurbits, and bananas. There are no known residential uses for carbofuran.

Carbon disulfide is a volatile organic compound that may be synthetic or naturally occurring. It is used in a multitude of industries, including the production of rubber, viscose rayon, cellophane, pesticides, and carbon tetrachloride. It is readily volatile, thus all routes of exposure (ingestion, inhalation and dermal) are relevant if one is exposed via drinking water.

Volatile organic chemical. It was previously used in pesticides, fire extinguishers, and cleaning products as well as to produce refrigerator fluid and aerosols. These uses are now banned due to its harmful health effects, but it still has certain limited industrial applications, for example synthesizing propellants and other chemicals. Because it is readily volatile, all routes of exposure (ingestion, inhalation and dermal) are relevant if one is exposed via drinking water.

Chaetomium is a genus of fungi that is commonly found in soil and decaying plant material. It is known for its ability to degrade cellulose and is often associated with water-damaged buildings. The spores of Chaetomium can be airborne and may contribute to indoor air quality issues.

Anion comprised of chlorine and oxygen; a disinfection byproduct of chlorine dioxide water treatment and a component of the compound sodium chlorate

Chlorine is a chemical element with the symbol Cl and atomic number 17. It is a yellow-green gas at room temperature and is a strong oxidizing agent. Chlorine is commonly used in water treatment to kill bacteria and other pathogens.

Chlorine is a chemical element with the symbol Cl and atomic number 17. It is a yellow-green gas at room temperature and is a strong oxidizing agent. Chlorine is commonly used in water treatment to kill bacteria and other pathogens, making water safe for drinking.

Chlorine dioxide is a chemical compound with the formula ClO2. It is a yellowish-green gas at room temperature and is used primarily as a bleaching agent and disinfectant. Chlorine dioxide is effective in killing bacteria, viruses, and other pathogens in water.

Chlorite is a chemical compound that is a derivative of chloric acid. It is often found in drinking water as a byproduct of chlorine disinfection processes. Chlorite can also occur naturally in some water sources.

Chlorodifluoromethane, also known as HCFC-22, is a colorless gas with a sweet odor. It is used primarily as a refrigerant and in the production of fluoropolymers. It has a boiling point of -40.8 °C and is classified as a hydrochlorofluorocarbon (HCFC).

Member of trihalomethanes (THMs) that form in water treated with chlorine and is generally the most abundant THM formed in drinking water

Naturally occurring volatile organic compound and a halomethane, which is a derivative of methane with one or more hydrogens replaced by halogen atoms (i.e. F, Cl, Br, or I). It is most often used in the production of silicones, rubber, and other materials. Historically chloromethane was used as a refrigerant but is no longer used due to its toxicity. Chloromethane is one of many known disinfection byproducts produced when water is treated with chlorine, but EPA does not regulate levels of chloromethane in drinking water. Chloromethane is readily volatile, thus all routes of exposure (ingestion, inhalation and dermal) are relevant if one is exposed via drinking water. Exposure to elevated levels of chloromethane has been associated with toxicity to the nervous system.

Chlorpyrifos is an organophosphate insecticide used on crops and for mosquito control.

Naturally occurring element that is widely used in manufacturing processes to make metal alloys such as stainless steel. Chromium is also present in some consumer products. Of the two most common forms of chromium—chromium (III) and (VI)—chromium (VI) is the more toxic form. Hexavalent chromium (VI) is associated with adverse gastrointestinal and hematological effects when ingested. Trivalent chromium (III), on the other hand, is an essential nutrient for human health in small amounts. EPA regulates both hexavalent and trivalent chromium, but standards are set assuming that a measurement of total chromium is 100 percent chromium (VI) to ensure that standards are most health protective.

Chromium VI, also known as hexavalent chromium, is a toxic form of the element chromium. It is a known carcinogen and can cause various health issues when ingested or inhaled. Chromium VI is often used in industrial processes, such as chrome plating, leather tanning, and wood preservation.

Cladosporium is a genus of fungi that is commonly found in indoor and outdoor environments. It thrives in damp conditions and can often be found on decaying organic matter, such as wood, leaves, and soil. Cladosporium species are known for their dark green or black appearance and can produce spores that are easily airborne.

Natural element used in pigment manufacture as well as to produce superalloys, which have various industrial and military applications. There are many unstable or radioactive isotopes of cobalt used for commercial and medical purposes, however these are rarely encountered in drinking water. Cobalt is essential to human health as a component of vitamin B12, though there is some evidence of adverse health effects following chronic oral exposure.

Coliform fecal bacteria are a group of bacteria found in the intestines of warm-blooded animals. They are used as an indicator of water quality and the potential presence of harmful pathogens. These bacteria are not typically harmful themselves but indicate that other pathogens may be present.

Naturally occurring metal that is widely used in plumbing, faucets, and fixtures

Cryptosporidium is a microscopic parasite that causes the diarrheal disease cryptosporidiosis. It is resistant to chlorine disinfection and can survive in water for long periods. The parasite is transmitted through the fecal-oral route, often via contaminated drinking water or recreational water.

Curvularia is a genus of fungi that can be found in soil and decaying plant material. It is known for its ability to thrive in various environmental conditions and can produce mycotoxins that may contaminate water sources.

Cyanide is a chemical compound that contains a carbon atom triple-bonded to a nitrogen atom. It is highly toxic and can exist in various forms, including gaseous hydrogen cyanide and solid cyanide salts. Cyanide is often used in industrial processes, such as mining and electroplating, and can also be found in certain plants and seeds.

DCPA (Dichloroacetic acid) is a herbicide that is used to control weeds in various crops. It is a chlorinated compound that can break down into several metabolites, which may also be present in drinking water.

Member of haloacetic acids (HAAs) that form as byproducts when chlorine reacts with organic matter

Member of trihalomethanes (THMs) that form in water treated with chlorine

Volatile organic compound (VOC) that was once used as a soil fumigant and nematicide (worm-killer) on over 40 crops in the United States. The EPA cancelled its application as an agricultural pesticide in 1989, and it is currently used in small quantities as an intermediate to synthesize other organic chemicals. DBCP is readily volatile, thus all routes of exposure (ingestion, inhalation and dermal) are relevant if one is exposed via drinking water. It has been detected in the ambient environment, including groundwater and drinking water.

Organobromine and a volatile organic compound. It is primarily used as a fumigant and pesticide, though it has largely been phased out of use in the US due to its ozone depleting effects in the atmosphere. Bromomethane is readily volatile, thus all routes of exposure (ingestion, inhalation and dermal) are relevant if one is exposed via drinking water. Exposure to elevated levels of bromomethane has been associated with adverse developmental, nervous system, and respiratory outcomes and genotoxicity.

Dicamba is a systemic herbicide used to control broadleaf weeds. It is a benzoic acid derivative and acts by mimicking the natural plant hormone auxin, leading to uncontrolled growth and eventual plant death.

Member of haloacetic acids (HAAs) that form as byproducts when chlorine reacts with organic matter

Dichloromethane (methylene chloride) is a human-made volatile organic compound and a halomethane, or a derivative of methane with one or more hydrogens replaced by halogen atoms (i.e. F, Cl, Br, or I). It is widely used in paint, aerosols, insecticides, cleaning fluids, and as an industrial solvent in metal and drug manufacturing. Dichloromethane is readily volatile, thus all routes of exposure (ingestion, inhalation and dermal) are relevant if one is exposed via drinking water. Health effects related to elevated dichloromethane exposure include liver problems, genotoxicity, and cancer. EPA classifies dichloromethane as a likely human carcinogen.

Most common type of fecal coliform bacteria

Enterococcus faecalis is a type of bacteria that is commonly found in the intestines of humans and animals. It is a gram-positive, facultative anaerobic bacterium that can survive in harsh environmental conditions. While it is a normal part of the gut flora, its presence in water indicates fecal contamination.

Epicoccum species are a group of fungi that are commonly found in soil and decaying organic matter. They are known for their ability to produce a variety of secondary metabolites, some of which may have antimicrobial properties. These fungi can be found in various environments, including agricultural fields and forests, and are often associated with plant material.

Volatile organic compound (VOC) that has historically been used as a soil fumigant and lead gasoline additive

Exophiala is a genus of fungi that can be found in various environments, including soil and decaying organic matter. It is known for its dark pigmentation and can sometimes be associated with human infections, particularly in immunocompromised individuals.

Naturally occurring mineral in the environment and an essential element of tooth enamel

Fusarium is a genus of filamentous fungi that are commonly found in soil and plant debris. They can produce mycotoxins that are harmful to humans and animals. Fusarium species are known to cause plant diseases and can contaminate crops, leading to food safety concerns.

Trade name for a technology used to create some of the synthetic compounds known as per- and polyfluoroalkyl substances (PFAS) widely used to make products more resistant to stains, water, and grease

Herbicide widely applied to control weeds on agricultural crops, including many fruits, vegetables, nuts, corn, and soybean. It is also used for non-agricultural uses like conservation land, rangeland, rights of way, and aquatic environments.

Gross alpha activity is a measure of the total alpha particle activity in a water sample, excluding radon and uranium. It is used to assess the presence of radioactive contaminants in drinking water.

Gross alpha activity measures the total amount of radioactivity in a water sample emitted by decaying alpha-emitting elements, notably radioactive isotopes of uranium, radium, and radon. Alpha emitters are used to treat cancer, as an eliminator of static in paper mills and in other products like smoke detectors. Radioactive atoms release high energy alpha particles that pull electrons off of the atoms in cells. This process is called ionizing radiation, and may lead to harmful changes in cells and tissues. The toxicity of an alpha emitter depends on the amount of energy it releases and how organ systems respond to that energy. Exposure to elevated gross alpha activity is associated with increased cancer risk and genotoxicity, but toxicity to individual systems is dependent on the type of alpha emitter present.

Helicobacter pylori is a type of bacteria that can cause infections in the stomach. It is known to be a major cause of peptic ulcers and is associated with stomach cancer. The bacteria can survive in the harsh acidic environment of the stomach and can be transmitted through contaminated food and water.

Synthetic organic compound previously used as a fungicide, in wood preservation, and in the production of rubber, aluminum, and dyes before being phased out due to environmental and health concerns. It is currently formed as a byproduct during the production of chemical solvents and pesticides. Once hexachlorobenzene enters the environment, it can remain there for many years. It has been detected in surface water, groundwater, and drinking water.

Important chemical intermediate in the production of certain pesticides, including heptachlor, chlordane, and dieldrin. It is also used to manufacture flame retardants, dyes, pharmaceuticals, and resins. It is readily volatile, thus all routes of exposure (ingestion, inhalation and dermal) are relevant if one is exposed via drinking water.

Naturally occurring heavy metal commonly found in tap water

Legionella pneumophila is a bacterium that can cause a severe form of pneumonia known as Legionnaires' disease. It is a gram-negative bacterium that thrives in warm water environments and can be found in natural water bodies as well as man-made water systems.

Lithium is a soft, silvery-white metal that belongs to the alkali metal group. It is highly reactive and flammable, and must be stored in mineral oil. Lithium is used in batteries, mood-stabilizing drugs, and other applications.

Transition metal commonly found at low levels in soil, air, and water and in food as an essential nutrient

Mercury is a naturally occurring metal that exists in three forms: metallic (or elemental), inorganic and organic mercury (including methylmercury). Inorganic mercury is the form regulated in drinking water as it is the form most likely to exist in drinking water. Inorganic mercury compounds are used in fungicides, skin lightening creams, antiseptics, preservatives and paints/dyes, though they are being phased out due to environmental concerns. Drinking water standards for inorganic mercury in drinking water are based on kidney damage observed in animal studies.

Molybdenum is a naturally occurring metal and essential nutrient for most living organisms. It is also used in metallurgy and as a component in fertilizers to prevent molybdenum deficiency in plants. Exposure to elevated concentrations of molybdenum beyond what is necessarily for nutrition may lead to adverse kidney effects.

Member of a family of contaminants called haloacetic acids (HAAs), which form as byproducts when chlorine water disinfection is used to kill harmful microorganisms

Member of a family of contaminants called haloacetic acids (HAAs), which form as byproducts when chlorine, used as a disinfectant to kill harmful microorganisms, reacts with organic matter

n-Nitrosodimethylamine (NDMA) is a volatile organic compound that occurs in drinking water as a byproduct of disinfection using chlorine or chloramines. It was once used to produce liquid rocket fuel, antioxidants, softeners, and lubricants. NDMA is readily volatile, thus all routes of exposure (ingestion, inhalation and dermal) are relevant if one is exposed via drinking water.

N-Ethyl Perfluorooctanesulfonamidoacetic Acid is a synthetic chemical compound that belongs to the class of perfluoroalkyl substances (PFAS). It is used in various industrial applications, including the production of water-repellent coatings and surfactants. This compound is characterized by its strong carbon-fluorine bonds, which make it resistant to degradation in the environment.

N-Methyl Perfluorooctanesulfonamidoacetic Acid is a synthetic chemical compound used in various industrial applications, particularly in the production of fluorinated surfactants. It is characterized by its perfluorinated carbon chain, which imparts unique properties such as water and oil repellency.

Naturally occurring metal that can be found in tap water primarily due to the leaching of nickel alloys in plumbing and fixtures. It is primarily used to make stainless steel and other alloys used for coins, jewelry, and appliances. Approximately 10-20% of the population is sensitive to nickel, which may cause a skin rash after exposure through contact or ingestion.

Non-spore forming fungi are a type of fungi that do not produce spores as part of their reproductive cycle. They can be found in various environments, including soil, water, and organic matter. These fungi can be significant in the decomposition of organic materials and play a role in nutrient cycling.

Orthophosphate is a chemical compound that contains phosphorus in its most basic form. It is often found in fertilizers and is a key nutrient for plant growth. In water, it can exist as a dissolved ion and is commonly measured to assess water quality.

Organic chemical once widely used as a wood preservative and pesticide

Perchlorate is a chemical compound that contains a chlorine atom bonded to four oxygen atoms. It is a highly soluble salt that can contaminate drinking water supplies and is often used as a component in rocket fuel, explosives, and fireworks.

Part of a class of synthetic compounds known as polyfluoroalkyl substances (PFAS) widely used to make products more resistant to stains, water, and grease. For example, PFAS have been used in nonstick cookware, textiles, food packaging, electronics, cleaners, and many other consumer products.

Part of a class of synthetic compounds known as per- and polyfluoroalkyl substances (PFAS) widely used to make products more resistant to stains, water, and grease. PFDA has been used in coatings on food packaging, furniture, upholstery, and carpeting, and as a lubricant, plasticizer, and corrosion inhibitor. Like many other PFAS, PFDA is resistant to breakdown in the environment and the body. High levels of ingested PFDA may result in adverse liver, developmental, and immune effects, but research on the health effects of PFDA is still ongoing.

Perfluoroheptanoic acid (PFHpA) is a perfluoroalkyl substance (PFAS) that is used in various industrial applications, including the production of fluoropolymers. It is characterized by a carbon chain of seven carbon atoms, fully fluorinated, which makes it resistant to degradation and highly persistent in the environment.

Part of a class of synthetic compounds known as per- and polyfluoroalkyl substances (PFAS) widely used to make products more resistant to stains, water, and grease. PFHxS has been used in protective coatings for carpets, paints, and textiles and as a surfactant in industrial processes. It may also be found in food contact papers, fire-fighting foams, and cleaning products. PFHxS production has been phased out in the US, but ongoing concerns exist due to its high persistence in the environment and the body, legacy uses, and presence in imported goods. Exposure to elevated PFHxS levels may result in adverse effects to the thyroid and liver.

Perfluorohexanoic acid (PFHxA) is part of a class of synthetic compounds known as per- and polyfluoroalkyl substances (PFAS) widely used to make products more resistant to stains, water, and grease. PFHxA is not currently commercially produced, but results from the breakdown of other PFAS and as a potential impurity in chemical processing. Like many other PFAS, it is highly persistent in the environment and the body. Adverse health effects associated with elevated PFHxA levels include liver and developmental toxicity.

Part of a class of synthetic compounds known as per- and polyfluoroalkyl substances (PFAS) widely used to make products more resistant to stains, water, and grease. PFNA serves as a processing aid for fluoropolymers, most notably the temperature resistant plastic used in tanks, valves, batteries, and fishing lines. It has also been used in producing fire-fighting foams. PFNA production is currently being phased out in the US, but exposure is still a major concern due to its high degree of persistence in the environment and in the body, as well as its presence in legacy products and imported goods. Adverse health effects related to elevated PFNA levels include developmental, liver, and immunological toxicity as well as increased cholesterol.

Part of a class of synthetic compounds known as per- and polyfluoroalkyl substances (PFAS) widely used to make products more resistant to stains, water, and grease. It is found in fabrics, fire-fighting foams, cleaning products, hydraulic fluids, metal plating, and paper. Although PFOS production has been phased out in the US, exposure is still a major concern due to its high degree of persistence in the environment and in the body as well as the use of legacy products and imported goods. Many adverse health effects have been linked to PFOS exposure, including developmental, liver, and immunological problems and increased cancer risk. EPA has found that there is suggestive evidence that PFOS is a human carcinogen.

Perfluorooctanoic acid (PFOA) is a synthetic chemical that belongs to a group of chemicals known as per- and polyfluoroalkyl substances (PFAS). It is used in various industrial applications and consumer products for its water- and grease-resistant properties.

Perfluorotetradecanoic acid (PFTeDA) is a synthetic chemical belonging to the class of perfluoroalkyl substances (PFAS). It is characterized by a long carbon chain with fluorine atoms attached, making it highly resistant to degradation. PFTeDA is used in various industrial applications, including the production of water- and grease-resistant coatings.

Perfluorotridecanoic acid (PFTrDA) is a perfluoroalkyl substance (PFAS) that is used in various industrial applications. It is characterized by a long carbon chain with fluorine atoms attached, making it resistant to degradation and highly persistent in the environment.

Member of a class of organic chemicals called polycyclic aromatic hydrocarbons (PAHs) that occur naturally in coal tar and crude oil. It is produced commercially as an intermediate in producing soaps, plastics, and pharmaceuticals, and as an insecticide, herbicide, and fungicide.

Naturally occuring semi-volatile organic compound that is found naturally in coal and peat

Radium-226 is a radioactive isotope of radium, which is a naturally occurring element found in uranium ores. It is a decay product of uranium-238 and is known for its radioactive properties, emitting alpha particles and gamma radiation.

Radium-228 is a radioactive isotope of radium that occurs naturally in uranium and thorium ores. It is part of the decay chain of uranium-232 and has a half-life of 5.75 years. Radium-228 can be found in groundwater and can contaminate drinking water supplies.

Radium is a naturally occurring radioactive metal that is part of the uranium decay series. It is found in trace amounts in soil, rock, and water. Radium is known for its radioactive properties and can emit alpha, beta, and gamma radiation. It is a heavy metal and can be harmful to human health when ingested or inhaled.

Radon is a naturally occurring radioactive gas. Radon may be used in detecting seismic activity, radiography, radiation therapy, and calibrating radon monitoring devices. Radon and its breakdown products emit alpha, beta, and gamma particles that may be harmful to health. In fact, radon is the most significant source of human exposure to radiation. It is readily volatile, thus all routes of exposure (ingestion, inhalation and dermal) are relevant if one is exposed via drinking water. Elevated levels of radon in drinking water may lead to an increased risk of lung cancer due to the potential of radon gas formation. States have widely varying acceptable radon levels (300-10,000 pCi/L), but generally treatment is recommended at levels greater than 10,000 pCi/L.

Naturally occurring element that is usually found in combination with other substances, including sulfide minerals, silver, copper, lead, and nickel minerals. It is used in photographic devices, gun bluing, plastics, paints, anti-dandruff shampoos, vitamin and mineral supplements, fungicides, and certain types of glass. Selenium is an essential nutrient at low levels, but exposure to high levels may result in dermal and neurological problems.

Silver is a metallic element that is found in nature in its pure form or as part of various minerals. It is known for its high conductivity and is used in various industrial applications, including electronics and photography.

Simazine is an organic chemical and herbicide used to control weeds in various crops, including corn, almonds, grapes, and oranges. It is also used to control algae overgrowth in aquatic environments, and for non-agricultural sites, such as rights-of-way.

Sodium is a chemical element with the symbol Na (from Latin 'Natrium') and atomic number 11. It is a soft, silvery-white, highly reactive metal that belongs to the alkali metals group. Sodium is essential for life and is found in many foods, but excessive sodium intake can lead to health issues.

Strontium-90 is a radioactive isotope of strontium that is produced as a byproduct of nuclear fission. It has a half-life of about 28.8 years and emits beta particles as it decays. Strontium-90 can replace calcium in biological systems, leading to potential health risks.

Various organisms produce styrene naturally, but styrene is also a synthetic chemical used for manufacturing plastic, rubber, and resins. It is present in a variety of consumer products containing styrofoam (polystyrene) and other plastics, including packaging materials, housewares, drinking cups, food packaging items, carpet backing, and home insulation materials. Styrene is readily volatile, thus all routes of exposure (ingestion, inhalation and dermal) are relevant if one is exposed via drinking water. Prolonged exposure to elevated styrene levels may lead to neurotoxic and genotoxic effects, as well as an increased risk of developing cancer. However, EPA has not assigned a cancer risk for styrene due to lack of adequate evidence.

Volatile organic compound (VOC), also known as perchloroethylene (PCE), known as the 'dry cleaning fluid'

Highly toxic metal produced as a byproduct of smelting and coal-burning facilities and then used primarily in the manufacture of electronic devices. Thallium is frequently found combined with other substances such as bromine, chlorine, fluorine, and iodine to form salts.

Total bacteria refers to the total number of bacteria present in a water sample. It is an important indicator of water quality and can indicate the presence of pathogens that may pose health risks.

Group of common bacteria found in soil, water, and the gut and fecal waste of humans and other warm-blooded animals

Total coliforms are a group of bacteria found in the environment, including in soil, vegetation, and feces of warm-blooded animals. They are used as an indicator of water quality and the potential presence of harmful pathogens.

Group of contaminants that are primarily formed as byproducts when chlorine reacts with organic matter

Group of contaminants that form in drinking water systems when a disinfectant, typically chlorine, reacts with organic matter

Synthetic organic mixture of almost 700 chemicals previously used as a pesticide in the United States before it was banned by the EPA in 1990

Member of haloacetic acids (HAAs) that form as byproducts when chlorine reacts with organic matter

Solvent that is used primarily for metal degreasing applications, as an intermediate for the manufacture of other chemicals, as an industrial solvent, and in dry cleaning and textile operations. TCE is the most commonly reported organic contaminant in drinking water and is readily volatile, thus all routes of exposure (ingestion, inhalation and dermal) are relevant if one is exposed via drinking water. The EPA has deemed trichloroethylene as 'likely to be carcinogenic to humans' by all routes of exposure based on the association between TCE exposure and kidney cancer. At low concentrations, TCE can adversely impact the immune system and development outcomes.

Uranium is a weakly radioactive heavy metal found naturally in bedrock and used in nuclear weapons, some ceramics, electron microscopy stains, photography toners, and certain fertilizers. Uranium is weakly radioactive because all of its isotopes (Uranium-234, Uranium-235, and Uranium-238) are unstable. Ninety-nine percent of naturally existing uranium is in the isotope form uranium-238. The EPA has established a maximum contaminant level for uranium in drinking water in response to human and animal studies indicating kidney toxicity and and increased risk of cancer.

Vanadium is a rare earth metal that is widely distributed in the earth's crust. The primary uses of vanadium are in the steel manufacturing industry and oil refineries and power plants using vanadium-rich fuels. Other manufacturing uses of vanadium include the production of pesticides, dyes, inks, and other chemicals. Humans are normally exposed to low concentrations of vanadium in food. Vanadium may be an essential element for human nutrition, but there is no consensus in the scientific literature. Potential adverse health effects due to chronic exposure are primarily thought to be developmental based on animal studies, but there is limited evidence.

Vinyl chloride (also called chloroethene) is a synthetic volatile organic compound and a member of a class of chemicals called organochlorides. It is primarily used to produce polyvinyl chloride (PVC); PVC is contained in a multitude of consumer products, including pipes, toothbrushes, toys, tool handles, automobile parts, cosmetics, wood varnish, and medical devices. It is readily volatile, thus all routes of exposure (ingestion, inhalation and dermal) are relevant if one is exposed via drinking water.

Most common of three trichlorobenzenes (TCBs) that have been used as industrial solvents and chemical intermediates. 1,2,4-TCB is used in large quantities to dissolve materials (oils, waxes, resins, greases, and rubber) as well as in the production of dyes and textiles. It is readily volatile, thus all routes of exposure (ingestion, inhalation and dermal) are relevant if one is exposed via drinking water. TCBs evaporate easily from surface water and bind tightly to soils and suspended material; they have, nonetheless, been detected in surface water, groundwater, and finished drinking water.

Herbicide widely used to control weeds on grasses (lawns and turf)

Acetochlor is a selective herbicide used to control annual grasses and broadleaf weeds in corn and soybean crops. It is a member of the chloroacetanilide class of herbicides and works by inhibiting the growth of weeds.

Asbestos is a group of naturally occurring silicate minerals composed of long, thin fibrous crystals. It is known for its heat resistance, tensile strength, and insulating properties, making it useful in various industrial applications.

Alkaline metal that occurs in nature as a mineral found in many different compounds

Chloramine is a chemical compound formed when ammonia is added to chlorine in water treatment processes. It is used as a disinfectant to kill bacteria and other pathogens in drinking water.

Cis-1,2-xichloroethylene (cis-1,2-DCE) is one of two isomers of the volatile organic chemical 1,2-dichloroethylene. It is readily volatile, thus all routes of exposure (ingestion, inhalation and dermal) are relevant if one is exposed via drinking water. The other isomer, trans-1,2-DCE, is used as a solvent in industrial processing and for extracting meat and fish oils, but cis-1,2-DCE is not currently used in industry. It has been detected in both surface water and groundwater.

Volatile organic compound that occurs naturally in coal tar and petroleum. It is a member of a class of compounds called BTEX, which are among the most abundantly produced chemicals in the world, notably created and used in petroleum processing and the production of consumer goods. Ethylbenzene is primarily used as a precursor for styrene, which is used in styrofoam. Additional products that include ethylbenzene are gasoline, carpet glues, varnishes, pesticides, tobacco products, and paints. Ethylbenzene is readily volatile, thus all routes of exposure (ingestion, inhalation and dermal) are relevant if one is exposed via drinking water. Health effects associated with elevated ethylbenzene exposures include liver and kidney toxicity.

Iron is an abundant, naturally occurring metal in the environment that exists in three forms in water: ferrous ('clear water iron'), ferric ('red water iron'), and organic iron. Ferric and ferrous iron are both inorganic forms, differing in oxidation states. Organic iron consists of elemental iron bound to organic compounds, typically acids. Iron is commonly found in tap water and it is known for causing reddish or yellowish discoloration and staining. Ferric iron gives water a reddish-brown tint, while organic iron can impart a more yellow color. Although ferrous iron is clear in water, it can still leave behind reddish-brown stains when it precipitates out. While iron in drinking water is not typically considered harmful to human health, the presence of iron can lead to or indicate other hazards, such as pipe corrosion.

Methyl Tertiary Butyl Ether (MTBE) is a volatile organic compound that is used as a fuel additive to increase octane ratings and reduce engine knocking. It is a colorless liquid with a distinctive odor and is soluble in water.

Inorganic nonmetal compounds that form naturally when nitrogen combines with oxygen or ozone

Nitrate (NO3) is a chemical compound that consists of one nitrogen atom and three oxygen atoms. It is commonly found in fertilizers and can enter drinking water supplies through agricultural runoff, wastewater discharge, and natural deposits in the soil.

Nitrite is a chemical compound with the formula NO2. It is a nitrogen oxoanion and is often found in water as a result of the breakdown of organic matter or from agricultural runoff. Nitrite can be harmful in high concentrations and is often monitored in drinking water.

Compounds consisting of nitrogen and oxygen atoms; naturally occurring and help sustain plant and animal life

Part of a class of synthetic compounds known as polyfluoroalkyl substances (PFAS) widely used to make products more resistant to stains, water, and grease. PFBA is a breakdown product of other PFAS compounds used in food packaging, stain resistant clothing and carpets, and was previously manufactured and used in the manufacturing of photographic film but has since been phased out of production.

Perfluorododecanoic acid (PFDoA) is part of a class of synthetic compounds known as per- and polyfluoroalkyl substances (PFAS) widely used to make products more resistant to stains, water, and grease. It is found as a breakdown product of food packaging, sofas, and carpets. Like many other PFAS, PFDoA is highly persistent in the environment and the body. More research is required to understand the health effects of PFDoA, but elevated levels have previously been associated with liver toxicity.

Perfluoroundecanoic acid (PFUnA) is part of a class of synthetic compounds known as per- and polyfluoroalkyl substances (PFAS) widely used to make products more resistant to stains, water, and grease. It has been used in food packaging, sofas, and carpets. Like many other PFAS, PFUnA is highly persistent in the environment and the body. PFUnA is similar in structure to the better-known perfluorooctanoic acid, or PFOA, which has multiple well-documented health effects. More research is required to understand the health impacts of elevated PFUnA, but elevated exposure has been associated with liver and developmental toxicity in animal studies.

Metallic element with both stable and radioactive isotopes

Metal commonly used to line cans for food, beverages, and aerosols. Tin compounds are also used in a variety of plumbing materials including brass, bronze, pewter, and polyvinyl chloride, and in solder used to join pipes.

Naturally occurring metal and an essential nutrient for human health

Synthetic volatile organic compound (VOC) and one of three forms of dichlorobenzene (referred to collectively as DCBs). 1,2-DCB is used to produce herbicides. It is readily volatile, thus all routes of exposure (ingestion, inhalation and dermal) are relevant if one is exposed via drinking water.

Bromochloromethane is a chemical compound that is used as a solvent and in the production of other chemicals. It is a colorless liquid with a sweet odor and is classified as a halomethane. It is known for its volatility and can easily evaporate into the air.

Synthetic volatile organic compound (VOC). It is used as an industrial solvent, degreaser and as in intermediate in chemical synthesis. Chlorobenzene may have aromatic, almond-like odor and taste. It is readily volatile, thus all routes of exposure (ingestion, inhalation and dermal) are relevant if one is exposed via drinking water.

Dalapon is a herbicide used to control weeds in various crops. It is a synthetic compound that inhibits the growth of certain plants by interfering with their metabolic processes.

Metolachlor is a synthetic organic compound used as an herbicide to control grassy weeds on agricultural crops like corn and soybeans. It is known commercially as Bicep or Dual. It works by preventing the weeds from synthesizing long chain fatty acids that they need to survive. Metolachlor can bind to soil particles or leach through soil and enter groundwater depending on a variety of factors, including soil composition and precipitation. It has been detected in surface water and groundwater. Metolachlor and its degradates (metolachlor ESA and OXA) can remain in soil and water for months before they are fully broken down.

Tritium is a radioactive isotope of hydrogen, represented as ³H or T. It is produced naturally in the atmosphere through cosmic ray interactions and can also be generated in nuclear reactors. Tritium is a weak beta emitter and has a half-life of about 12.3 years.

Xylenes are a group of three isomers of dimethylbenzene, which are colorless, flammable liquids with a sweet odor. They are commonly used as solvents in the printing, rubber, and leather industries, and as a component in gasoline.

Synthetic volatile organic compound (VOC) and one of three forms of dichlorobenzene (DCBs). It has been used to produce herbicides, dyes, pharmaceuticals, and insecticides, but its application in pesticide synthesis has been cancelled. 1,3-Dichlorobenzene may have a sharp odor in drinking water. It is readily volatile, thus all routes of exposure (ingestion, inhalation and dermal) are relevant if one is exposed via drinking water.

Methyl ethyl ketone is an organic solvent used to produce rubber, wax, resin, lacquer, varnish, paint remover and glue. It is readily volatile, thus all routes of exposure (ingestion, inhalation and dermal) are relevant if one is exposed via drinking water. Though it evaporates easily, methyl ethyl ketone has been detected in surface water and drinking water.

Anion composed of sulfur and oxygen, is almost universally present in water