For the final phase of TAP, we conducted NTA to identify chemicals captured using water filter cartridges that were attached to participants' water faucets for a month or so. In typical drinking water analysis, you only find the chemicals that you look for with testing. NTA is a different way to test for chemicals. It does not begin with a specific list of chemicals to look for. It is useful because there may be chemicals in water besides the ones we know to look for.
We detected a total of 38 chemicals in the entire NTA study. Not every chemical was in each water filter sample, but a few chemicals were detected in every sample. These chemicals are listed below.
Disinfection byproducts
Chemical name About this chemical Chlorodibromomethane Byproduct of water chlorination. May increase risk of cancer and possibly cause reproductive problems such as miscarriage or low birthweight babies. Bromoform Byproduct of water chlorination. May increase risk of cancer and possibly cause reproductive problems such as miscarriage or low birthweight babies. Per-and polyfluoroalkyl substances (PFAS)
Chemical name About this chemical Perfluorooctanoic acid This group of chemicals are known as "forever chemicals" because they persist in the environment. Used in non-stick pans, waterproof and grease-proof coatings for food wrappers, clothing, upholstered furniture, and carpeting as well as many industrial uses including as fire-fighting foams. May cause reproductive and developmental effects, including lower birth weights. May increase risks of some cancers and interfere with natural hormones. May suppress the immune system. Perfluorooctanesulfonic acid Perfluorohexanoic acid Perfluorobutanesulfonic acid Pesticides or agricultural chemicals
Chemical name About this chemical Simazine Weed killer. May interfere with hormones and cause cancer. Atrazine Weed killer. May interfere with hormones and cause cancer. DEET Insect repellant. May cause seizures at high levels. 2,6-Diisopropylnaphthalene A plant-growth inhibitor. This chemical is used to prevent potatoes from sprouting while in storage. No health information available. Naturally-occurring chemicals
Chemical name About this chemical (6)-Gingerol This is the natural flavor in ginger. No known health effects. Nonanedioic acid (also known as Azelaic acid) Fatty acid naturally occurring in grains (wheat, barley, rye) and made by bacteria that live on our skin. It can be used in hair and skin care products. Used to treat acne. No known health effects. Tributyl citrate Plant-based chemical used in dish soap, nail products, bath products, hair dyes, facial cleansers. No known health effects. Household and personal care
Chemical name About this chemical Tris(2-chloroisopropyl)phosphate Flame retardant for foam padding and cushions. May cause cancer. Butylated hydroxytoluene Preservative and fragrance in many cleaning products, cosmetics and personal care products. Used in food packaging. May cause cancer and interfere with hormones. Ethylparaben Preservative and fragrance in many cosmetics, shampoos and lotions. May interfere with hormones. Benzophenone Sunscreen in some lotions and cosmetics. May cause cancer. Dimethylphthalate In plastics, insect repellants and pesticides. May affect the kidney and growth, based on animal studies. Dibutyl phthalate Softener in plastic gloves, tubing, garden hoses, shoes, perfumes and other products containing fragrances, and nail polishes. May interfere with hormones and the reproductive system. Benzyl butylphthalate In vinyl flooring, paints, and other vinyl products. May interfere with hormones and the reproductive system. Di-(2-ethylhexyl)phthalate In vinyl products and some soft plastics. May cause cancer, birth defects and reproductive harm. Octaethylene glycol In bath products, cosmetics, moisturizer, children's art products, dental care, eye drops. No known health effects. Hexaethylene glycol In makeup, automotive fluids. No known health effects. Di-p-methylbenzylidenesorbitol Used in medical ointments and personal care lotions to keep ingredients from separating. No health information available. Lauryldiethanolamine Used in hair conditioner. No health information available. Diphenyl oxide Used as a fragrance and deodorizer in cleaning products, laundry products, perfumes and air fresheners. Flavoring agent in foods. No health information available. 1,2-Dichlorobenzene Solvent used in air fresheners, automotive products, adhesives, sealants, corrosion inhibitors, paints, hydraulic fluids, floor cleaners, and industrial uses. No health information available. Industrial chemicals
Chemical name About this chemical 4-vinylcyclohexene Used to make rubber and plastic. Industrial chemical. May interfere with hormones and cause cancer. 1,3-Isobenzofurandione, 5-fluoro- Used in laboratories for manufacturing chemicals and pharmaceuticals. No health information available. Diethyl maleate Used in manufacturing the pesticide Malathion. It is also sometimes used in sealants, coatings, and adhesives. No health information available. 1,6-Hexanediol dimethacrylate Used in manufacturing polymers and can be used in adhesives, sealants, and inks. Used for acrylic nails and in dentistry. No health information available. Benzenesulfonic acid, 4-methyl-, dodecyl ester Used as a degreaser. It is also used to manufacture other chemicals. No health information available. 1-Bromooctane Solvent, used in chemical manufacturing. No health information available. 1-Bromodecane Used to make Decanal which is used in cleaning products such as air fresheners, bathroom cleaners, disinfectants, general household cleaners, and carpet cleaners. Generally used as a fragrance. No health information available. 1,2-Diphenylethanedione Used to manufacture other chemicals. No health information available. Chemicals of unknown use
Chemical name About this chemical 4-Trifluoromethylpiperidine No information available. 1-[2-(3-Nitrophenyl)-2-oxoethyl]pyrazin-1-ium bromide No information available. 1-Carboxy-2-(1H-imidazol-5-yl)-N,N,N-trimethylethan-1-aminium No information available.