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Contaminant Candidate List (CCL) and Regulatory Determination

Chemical Contaminants - CCL 4

Final CCL 4 Chemical Contaminants

 
Substance Name
CASRN1
Use
1,1-Dichloroethane
75-34-3 It is an industrial solvent and an intermediate in the synthesis of other compounds.
1,1,1,2-Tetrachloroethane
630-20-6
It is an industrial solvent and used in the synthesis of other chlorinated compounds.
1,2,3-Trichloropropane
96-18-4
It is an industrial solvent, cleaning and degreasing agent as well as an intermediate in the synthesis of the other compounds.
1,3-Butadiene
106-99-0
It is used in the production of rubber and plastics.
1,4-Dioxane
123-91-1
It is used as a solvent for cellulose formulations, resins, oils, waxes and other organic substances. It is also used in wood pulping, textile processing, degreasing, in lacquers, paints, varnishes, and stains; and in paint and varnish removers.
17alpha-estradiol
57-91-0
It is an estrogenic hormone found in some pharmaceuticals.
1-Butanol
71-36-3
It is a solvent and used in production of other chemicals. compounds.  It is present in a number of commercial products such as perfumes.
2-Methoxyethanol
109-86-4
It is used in a number of consumer products, such as synthetic cosmetics, perfumes, fragrances, hair preparations, and skin lotions.
2-Propen-1-ol
107-18-6
It is used in the production of other chemicals.
3-Hydroxycarbofuran
16655-82-6
It is a pesticide degradate, the parent, carbofuran, is used as an insecticide.
4,4'-Methylenedianiline
101-77-9
It is used in the production of polyurethanes foams, glues, rubber and spandex fiber.
Acephate
30560-19-1
It is an insecticide.
Acetaldehyde
75-07-0
It is a disinfection byproduct from ozonation; it is used in the production of other chemicals.
Acetamide
60-35-5
It is used as a solvent and plasticizer.
Acetochlor
34256-82-1
It is an herbicide for weed control on agricultural crops.
Acetochlor ethanesulfonic acid (ESA)
187022-11-3
Acetochlor ESA is an environmental degradate of acetochlor.
Acetochlor oxanilic acid (OA)
184992-44-4
Acetochlor OA is an environmental degradate of acetochlor.
Acrolein
107-02-8
It is used as an aquatic herbicide, rodenticide and industrial chemical.
Alachlor ethanesulfonic acid (ESA)
142363-53-9
Alachlor ESA is an environmental degradate of the pesticide alachlor (an herbicide for weed control on agricultural crops).
Alachlor oxanilic acid (OA)
171262-17-2
Alachlor OA is an environmental degradate of alachlor.
alpha-Hexachlorocyclohexane
319-84-6
It is a component of benzene hexachloride (BHC) and was formerly used as an insecticide.
Aniline
62-53-3
It is used as an industrial chemical, as a solvent, in the synthesis of explosives, rubber products and in isocyanates.
Bensulide
741-58-2
It is an herbicide.
Benzyl chloride
100-44-7
It is used in the production of other substances, such as plastics, dyes, lubricants, gasoline and pharmaceuticals.
Butylated hydroxyanisole
25013-16-5
It is used as a food additive (antioxidant).
Captan
133-06-2
It is a fungicide.
Chlorate
14866-68-3
Chlorate compounds are used in agriculture as defoliants or desiccants and may occur in drinking water because of use of disinfectants such as chlorine dioxide and hypochlorites.
Chloromethane (Methyl chloride)
74-87-3
It is used as a foaming agent and in the production of other substances.
Clethodim
110429-62-4
It is an herbicide.
Cobalt
7440-48-4
It is a naturally-occurring element and was formerly used as cobaltous chloride in medicines and as a germicide. It is a part of the vitamin B12 molecule
Cumene hydroperoxide
80-15-9
It is used as a catalyst is used in the production of other substances.
Cyanotoxins
Not applicable.
Toxins naturally produced and released by cyanobacteria ("blue-green algae"). The group of cyanotoxins includes, but is not limited to: anatoxin-a, cylindrospermopsin, microcystins, and saxitoxin.
Dicrotophos
141-66-2
It is an insecticide.
Dimethipin
55290-64-7
It is an herbicide and plant growth regulator.
Diuron
330-54-1
It is an herbicide.
Equilenin
517-09-9
It is an estrogenic hormone used in hormone replacement therapy.
Equilin
474-86-2
It is an estrogenic hormone and is used in hormone replacement therapy.
Erythromycin
114-07-8
It is used an antibiotic.
Estradiol (17-beta estradiol)
50-28-2
It is an isomer of estradiol found in some pharmaceuticals.
Estriol
50-27-1
It is a weak estrogenic hormone used in veterinary pharmaceuticals.
Estrone
53-16-7
It is a precursor of estradiol used in veterinary and human pharmaceuticals.
Ethinyl estradiol (17-alpha ethynyl estradiol)
57-63-6
It is an estrogenic hormone and is used in veterinary and human oral contraceptives.
Ethoprop
13194-48-4
It is an insecticide.
Ethylene glycol
107-21-1
It is used as antifreeze, in textile manufacturing and is a cancelled pesticide.
Ethylene oxide
75-21-8
It is a fungicidal and insecticidal fumigant.
Ethylene thiourea
96-45-7
It is used in the production of other substances, such as for vulcanizing polychloroprene (neoprene) and polyacrylate rubbers and is a metabolite of some fungicides.
Formaldehyde
50-00-0
It is an ozoneation disinfection byproduct, can occur naturally and has been used as a fungicide.
Germanium
7440-56-4
It is a naturally-occurring element and is commonly found as germanium dioxide in phosphors, transistors and diodes, and in electroplating. In some cases it has been sold as a dietary supplement.
HCFC-22
75-45-6
It is used as a refrigerant, as a low-temperature solvent, and in fluorocarbon resins, especially in tetrafluoroethylene polymers.
Halon 1011 (bromochloromethane) 74-97-5
It is used as a fire-extinguishing fluid and to suppress explosions, as well as a solvent in the manufacturing of some pesticides. May also occur as a disinfection by-product in drinking water.
Hexane
110-54-3
It is a component of gasoline and used as a solvent.
Hydrazine
302-01-2
It is used as an ingredient in the production of other substances, such as rocket propellants. It is also used in the production of plastics.
Manganese
7439-96-5
It is a naturally-occurring element used in a variety of applications including use in steel production to improve hardness, stiffness and strength.  It is an essential nutrient found in vitamin/mineral supplement and in fortified foods.
Mestranol
72-33-3
It is a precursor to ethinylestradiol used in veterinary and human pharmaceuticals.
Methamidophos
10265-92-6
It is an insecticide.
Methanol
67-56-1
It is used as an industrial solvent, a gasoline additive and as an anti-freeze ingredient.
Methyl bromide (bromomethane)
74-83-9
It has been used as a fumigant and fungicide.
Methyl tert-butyl ether (MTBE)
1634-04-4
It is used as an octane booster in gasoline, in the manufacturing of isobutene and as an extraction solvent.
Metolachlor
51218-45-2
It is an herbicide for weed control on agricultural crops.
Metolachlor ethanesulfonic acid (ESA)
171118-09-5
Metolachlor ESA is an environmental degradate of metolachlor.
Metolachlor oxanilic acid (OA)
152019-73-3
Metolachlor OA is an environmental degradate of metolachlor.
Molybdenum
7439-98-7
It is a naturally-occurring element and is commonly found as molybdenum trioxide.   It is used as a steel alloy.  It is an essential dietary nutrient found in foods and nutritional supplements.
Nitrobenzene
98-95-3
It is used in the production of aniline, and also as a solvent in the manufacturing of paints, shoe polishes, floor polishes, metal polishes, explosives, dyes, pesticides and drugs (such as acetaminophen).,
Nitroglycerin
55-63-0
It is used in the production of explosives, and in rocket propellants. It is also a pharmaceutical for the treatment of angina.
N-Methyl-2-pyrrolidone
872-50-4
It is a solvent in the chemical industry, and is used in the formulation of pharmaceuticals for oral and dermal delivery.
N-nitrosodiethylamine (NDEA)
55-18-5
It is a nitrosamine used as an additive in gasoline and in lubricants, as an antioxidant and as a stabilizer in plastics. It is formed in cured foods and during high temperature cooking of meats and fish, and may be a disinfection byproduct.
N-nitrosodimethylamine (NDMA)
62-75-9
It was formerly used in the production of rocket fuels, anti-oxidants and softeners for copolymers. It is formed in cured foods and during high temperature cooking. It may be a leachate from rubber gaskets and fittings and may form as a disinfection byproduct.
N-nitroso-di-n-propylamine (NDPA)
621-64-7
It is formed in cured foods and during high temperature cooking of meats and fish and may be a disinfection byproduct.  It is a contaminant in dinitrofluralin herbicides.
N-Nitrosodiphenylamine
86-30-6
It is used in the vulcanization of rubber and as an inhibitor of polymerization in the production of polystyrene. It may be a disinfection byproduct.
N-nitrosopyrrolidine (NPYR)
930-55-2
It is used in rubber production. It is formed in cured foods and during high temperature cooking of meats and fish and may be a disinfection byproduct.
Nonylphenol2
25154-52-3
The main use of nonylphenol is in the manufacture of nonylphenol ethoxylates, which have been used in a wide range of industrial applications and consumer products including laundry detergents, cleaners, degreasers, paints and coatings and other uses. Several other CASRNs are associated with nonyphenol due to varying chemical structures including: 104-40-5, 84852-15-3, 91672-41-2, and 139-84-4.
Norethindrone (19-Norethisterone)
68-22-4
Norethindrone is a synthetic hormone used in oral contraceptives and for hormone replacement therapy.
n-Propylbenzene
103-65-1
It is a constituent of asphalt and naptha and used in the manufacture of methyl styrene. It is a solvent for printing and dying of textiles.
o-Toluidine
95-53-4
It is used in the production of dyes, rubber, pharmaceuticals and pesticides.
Oxirane, methyl
75-56-9
It is an industrial chemical used in the production of other substances. It is a registered pesticide.
Oxydemeton-methyl
301-12-2
It is an insecticide.
Oxyfluorfen
42874-03-3
It is an herbicide.
Perfluorooctanesulfonic acid (PFOS)
1763-23-1
PFOS has been used to make carpets, leathers, textiles, fabrics for furniture, paper packaging, and other materials that are resistant to water, grease, or stains. It is also used in firefighting foams at airfields. Many of these uses have been phased out by its primary U.S. manufacturer; however, there are still some ongoing uses.
Perfluorooctanoic acid (PFOA)
335-67-1
PFOA has been used to make carpets, leathers, textiles, fabrics for furniture, paper packaging, and other materials that are resistant to water, grease, or stains. It is also used in firefighting foams at airfields. Many of these uses are being phased out by U.S. manufacturers; however, there are still some ongoing uses.
Permethrin
52645-53-1
It is an insecticide.
Profenofos
41198-08-7
It is an insecticide and an acaricide.
Quinoline
91-22-5
It is a component of coal tars and used in the production of other substances, and as a pharmaceutical (anti-malarial).
RDX (Hexahydro-1,3,5-trinitro-1,3,5-triazine)
121-82-4
It is an explosive.
sec-Butylbenzene
135-98-8
It is used as a solvent for coatings in organic synthesis, as a plasticizer and in surfactants.
Tebuconazole
107534-96-3
It is a fungicide.
Tebufenozide
112410-23-8
It is insecticide.
Tellurium
13494-80-9
It is a naturally-occurring element and is commonly used as sodium tellurite in bacteriology and medicine.
Thiodicarb
59669-26-0
It is an insecticide.
Thiophanate-methyl
23564-05-8
It is a fungicide.
Toluene diisocyanate
26471-62-5
It is used in the manufacturing of plastics.
Tribufos
78-48-8
It is an insecticide and used as a cotton defoliant.
Triethylamine
121-44-8
It is used in the production of other substances, as a stabilizer in herbicides and pesticides, in consumer products, in photographic chemicals and in carpet cleaners.
Triphenyltin hydroxide (TPTH)
76-87-9
It is a pesticide.
Urethane
51-79-6
It is a paint and coating ingredient (polyurethanes).
Vanadium
7440-62-2
It is a naturally-occurring element.  Vanadium pentoxide is a catalyst for the production of other substances catalyst. It is sometimes an ingredient in mineral supplements but is not classified as an essential nutrient
Vinclozolin
50471-44-8
It is a fungicide.
Ziram
137-30-4
It is a fungicide.

Notes

1Chemical Abstract Service Registration Number (CASRN#) - Chemical abstract service registry numbers are used in reference works, databases, and regulatory compliance documents by many organizations around the world to identify substances with a standardized name.

2 Due to varying chemical structures, there are several other CASRNs associated with nonylphenol in addition to 25154-52-3, including: 104-40-5, 84852-15-3, 91672-41-2, and 139-84-4. The CASRN provided by the nominator was selected for CCL 4, and the additional possible CASRNs are delineated here.

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