All Contaminants

Every contaminant detected nationwide is listed below. Use the search bar to find a specific contaminant.

Contaminant*	People served	# of states where detected
#
1,1,1,2-Tetrachloroethane	31,858	3
1,1,1-Trichloroethane	5,193,212	19
1,1,2,2-Tetrachloroethane	17,378	2
1,1,2,2-tetrafluoro-2-(1,2,2,2-tetrafluoro-ethoxy)ethane sulfonic acid (NVHOS)	861,204	1
1,1,2-Trichloroethane	620,103	8
1,1-Dichloroethane	19,958,490	38
1,1-Dichloroethylene	6,459,545	25
1,1-Dichloropropene	85,486	3
1,2,3-Trichlorobenzene	17,842	3
1,2,3-Trichloropropane	12,534,478	18
1,2,3-trimethylbenzene (hemellitol)	723	2
1,2,4-Trichlorobenzene	430,239	10
1,2,4-Trimethylbenzene	731,176	24
1,2-Dibromo-3-chloropropane (DBCP)	6,251,381	13
1,2-Dichloroethane	1,468,846	24
1,2-Dichloroethylene, cis-	5,762,717	31
1,2-Dichloroethylene, trans-	1,229,361	17
1,2-Dichloropropane	1,278,510	12
1,3,5-Trimethylbenzene	220,876	19
1,3-Butadiene	442,526	1
1,3-Dichloropropane	101,222	4
1,3-Dichloropropene	45,100	2
1,3-Dichloropropene, cis-	63,642	2
1,3-Dichloropropene, trans-	9,242	1
1,4-Dioxane	90,430,033	45
1-butanol	14,158,187	39
10:2 Fluorotelomer sulfonic acid (10:2 FTSA)	444	1
17-beta-Estradiol	251,974	1
2,2-Dichloropropane	56,239	5
2,3,7,8-TCDD (Dioxin)	81,890	3
2,4,5-T	7,342	1
2,4,5-TP (Silvex)	994,099	8
2,4-D	15,811,375	33
2,4-DB	306	1
2-Furancarboxyaldehyde	171,368	1
2-Hexanone	66,571	1
2-methoxyethanol	4,249,541	23
2-Methyl naphthalene	26	1
2-Methylbutane	49,396	1
2-propen-1-ol	1,177,283	16
3-Hydroxycarbofuran	343,873	2
4,8-dioxa-3H-perfluorononanoic acid (ADONA)	198,416	2
4-Androstene-3,17-dione	18,312,034	25
4:2 Fluorotelomer sulfonic acid (4:2 FTSA)	3,612	1
6:2 Fluorotelomer Sulfonate (6 2FTS)	153,292	1
6:2 Fluorotelomer sulfonic acid (6:2 FTSA)	198,185	2
8:2 Fluorotelomer Sulfonate (8:2FTS)	153,202	1
9-chlorohexadecafluoro-3-oxanonane-1-sulfonate	3,150	1
A
Acenaphthene	11,970	2
Acenaphthylene	11,970	2
Acetaldhyde	220,220	3
Acetochlor	381,561	3
Acetone	4,733,651	14
Alachlor (Lasso)	2,859,754	9
Aldicarb	29,300	3
Aldicarb sulfone	11,444	3
Aldicarb sulfoxide	905,658	7
Aldrin	56,109	4
alpha-Chlordane	155	1
Alpha-hexachlorocyclohexane	1,174,028	16
Aluminum	91,342,801	35
Anthracene	67,053	1
Antimony	15,840,266	42
Arsenic	108,260,504	50
Asbestos	461,275	13
Atrazine	43,018,065	36
B
Barium	209,651,790	50
Benzaldehyde	30,573	1
Benzene	971,339	28
Benzoic acid	3,600	1
Benzo[a]anthracene	67,573	3
Benzo[a]pyrene	4,649,843	17
Benzo[b]fluoranthene	250,566	4
Benzo[g,h,i]perylene	76,285	2
Benzo[k]fluoranthene	67,293	2
Benzyl alcohol	23,581	1
Beryllium	5,012,516	30
bis(2-chloroethyl) ether	322,720	3
Bromacil	429,863	2
Bromate	43,884,978	29
Bromide	28,750,698	24
Bromobenzene	15,792	2
Bromochloroacetic acid	54,547,728	24
Bromochloromethane	31,563,012	42
Bromodichloroacetic acid	1,837,920	3
Bromodichloromethane	236,994,263	48
Bromoform	157,063,639	48
Bromomethane	4,754,261	31
Butachlor	73,926	4
Butane	53,764	1
Butyl benzyl phthalate	60,101	2
Butyl citrate	52,395	1
Butylate	1,330	1
Butylated hydroxyanisole	320,048	6
C
Cadmium	7,043,344	42
Caffeine	392,151	1
Captan	138,789	1
Carbaryl	10,494	2
Carbofuran	380,303	6
Carbon tetrachloride	3,143,655	32
Chlorate	208,003,534	50
Chlordane	1,805,251	10
Chlorite	27,966,599	27
Chlorodibromoacetic acid	2,470,325	3
Chlorodifluoromethane	2,449,114	2
Chlorodifluoromethane	29,646,885	37
Chloroethane	384,868	15
Chloroform	237,206,221	48
Chloromethane	16,904,561	39
Chlorotoluene, o-	66,949	7
Chlorotoluene, p-	56,047	4
Chlorpyriphos	150,619	3
Chromium (hexavalent)	250,692,436	50
Chromium (total)	70,671,685	50
Chrysene	89,767	4
Cobalt	16,457,960	34
Cyanazine (Bladex)	16,869	2
Cyanide	27,444,677	39
Cyanide (free)	2,580,373	2
Cyclohexane	32,217	1
D
Dacthal	530,110	5
Dalapon	7,854,969	33
DCPA di-acid degradate	69,532	1
DCPA mono- and di-acid degradates	745,563	2
Ddt	40,610	1
Desethylatrazine	1,417,681	2
Desisopropylatrazine	41,517	1
Di(2-ethylhexyl) adipate	869,272	24
Di(2-ethylhexyl) phthalate	22,982,312	43
Di-n-butyl phthalate	107,269	5
Dibenz[a,h]anthracene	184,024	2
Dibromoacetic acid	164,616,355	45
Dibromochloromethane	227,433,407	48
Dibromomethane	1,704,467	17
Dicamba	681,733	10
Dichloroacetic acid	208,210,698	47
Dichloroacetonitrile	30	1
Dichlorobenzene, m-	57,458	6
Dichlorobenzene, o-	392,594	10
Dichlorobenzene, p-	770,417	23
Dichlorodifluoromethane	2,349,729	13
Dichloromethane (methylene chloride)	5,257,208	39
Dieldrin	1,225,292	9
Diethyl phthalate	60,256	4
Diisobutyl phthalate	11,624	1
Dimethipin	95,911	4
Dimethyl phthalate	36,123	3
Dinoseb	1,026,153	6
Diquat	2,015,202	11
Disulfoton	1,105	1
E
Endothall	75,798	6
Endrin	3,195,119	12
Estriol	18,808	2
Ethanesulfonic acid, 2-[1-[difluoro(1,2,2,2-tetrafluoroethoxy)methyl]-1,2,2,2-te	392,784	1
Ethinyl estradiol	3,231,839	4
Ethoprop	436,171	5
Ethyl ether	25,015	2
Ethylbenzene	7,094,773	45
Ethylene dibromide	1,533,365	22
F
Fluoranthene	11,354	2
Fluorene	79,023	3
Fluoride	252,367,438	50
Fonofos	25	1
G
gamma-Chlordane	155	1
Germanium	36,215,285	41
Glyphosate	419,389	7
H
Haloacetic acids (HAA5)	285,908,335	50
Haloacetic acids (HAA9)	259,877,900	50
Heptachlor	391,109	8
Heptachlor epoxide	1,827,087	17
Hexachlorobenzene (HCB)	375,022	6
Hexachlorobutadiene	15,872	2
Hexachlorocyclopentadiene	5,855,008	24
Hexadecanoic acid	2,020,913	1
Hexafluoropropylene Oxide Dimer Acid (HFPO-DA)	1,345,599	1
Hexane(s)	14,715	1
Hydrogen sulfide	8,090	3
I
Indeno[1,2,3-cd]pyrene	96,131	3
Iodomethane	5,006	1
Isobutane	43,219	1
Isooctyl alcohol	964	1
Isophorone	67,053	1
Isopropyl alcohol	27,515	3
Isopropyl chloride	279	1
Isopropyl ether	74	1
Isopropylbenzene	75,986	9
Isopropyltoluene, p-	59,012	6
L
Lindane	1,184,225	10
Lithium	3,044,654	4
M
Manganese	263,778,298	50
Mercury (inorganic)	6,281,056	40
Methane	850	1
Methomyl	22,329	4
Methoxychlor	345,627	10
Methyl ethyl ketone	4,909,039	9
Methyl isobutyl ketone	3,112,736	7
Methylcyclohexane	37,124	1
Methylcyclopentane	14,775	1
Metolachlor	4,413,576	18
Metolachlor ethane sulfonic acid	1,137,108	1
Metolachlor oxanilic acid	1,137,108	1
Metribuzin	248,343	3
Molybdenum	155,466,301	50
Monobromoacetic acid	98,407,090	44
Monochloroacetic acid	142,959,977	45
Monochlorobenzene (chlorobenzene)	1,894,698	17
MTBE	4,994,387	27
N
N-(carboxymethyl)-N,N-dimethyl-N-[3-(1H,1H,2H,2H-perfluoro-1-octanesulfonamido)p	330,214	1
n-Butyl alcohol	2,082	1
n-Butylbenzene	72,457	9
N-ethyl perfluorooctane sulfonamido acetic acid (N-EtFOSAA)	440,798	4
N-methyl perfluorooctanesulfonamidoacetic acid	234,812	4
N-Nitrosodi-N-butylamine	371,830	1
N-Nitrosodimethylamine (NDMA)	6,621,787	1
n-Propylbenzene	195,433	14
Naphthalene	215,803	20
Nitrate	236,944,533	49
Nitrate & nitrite	152,929,776	49
Nitrite	31,491,270	44
O
o-toluidine	11,955,405	24
Octadecanoic acid	1,595,117	1
Oxamyl (Vydate)	354,874	6
Oxyflurofen	870,286	6
P
Paraquat	14,186	2
Pcnb	34,472	1
Pentachlorophenol	2,487,411	19
Pentane	7,122	1
Perchlorate	11,701,797	9
Perfluoro(3,5,7,9-tetraoxadecanoic) acid (PFO4DA)	153,292	1
Perfluoro(3,5,7-trioxaoctanoic) acid (PFO3OA)	405,998	1
Perfluoro(3,5-dioxahexanoic) acid (PFO2HxA)	460,953	1
Perfluoro-2-ethoxypropanoic acid	389,493	1
Perfluoro-2-methoxyacetic acid (PFMOAA)	402,707	1
Perfluoro-2-methoxypropanoic acid	1,402,389	1
Perfluoro-2-methyl-3-oxahexanoic acid (GenX)	468,552	1
Perfluoro-3-methoxypropanoic acid (PFMOPrA)	153,292	1
Perfluoro-4-methoxybutanic acid (PFMOBA)	153,202	1
Perfluorobutane sulfonamide (FBSA)	1,173,208	1
Perfluorobutane sulfonate (PFBS)	11,542,757	16
Perfluorobutanoic acid (PFBA)	5,649,394	5
Perfluorodecanesulfonic acid (PFDS)	123	1
Perfluorodecanoic acid (PFDA)	3,022,553	6
Perfluorododecanoic acid (PFDoA)	581,799	1
Perfluoroheptane sulfonic acid (PFHpS)	308,918	3
Perfluoroheptanoic acid (PFHPA)	17,402,889	28
Perfluoroheptanoic acid (PFHpA)	33,477	1
Perfluorohexadecanoic acid (PFHxDA)	2,838	1
Perfluorohexane sulfonamide (FHxSA	296,658	1
Perfluorohexane sulfonate (PFHXS)	16,694,324	27
Perfluorohexanoic Acid	14,641,996	11
Perfluorononanoic acid (PFNA)	8,226,606	13
Perfluorooctane sulfonate (PFOS)	28,071,844	28
Perfluorooctanesulfonamide (PFOSA)	30,237	2
Perfluorooctanoic acid (PFOA)	24,356,620	30
Perfluoropentane sulfonic acid (PFPeS)	1,998,491	3
Perfluoropentanoic acid (PFPeA)	5,436,202	8
Perfluorotetradecanoic acid (PFTA)	2,838	1
Perfluorotridecanoic acid (PFTrDA)	3,612	1
Perfluoroundecanoic Acid (PFUnA)	1,463,352	4
Permethrin	1,568,867	9
PFOS and PFOA	1,573,038	2
Phenanthrene	76,347	3
Phenols	914,261	2
Picloram	1,094,155	29
Polychlorinated biphenyls (PCBs)	420,598	3
Potassium-40*	524	1
Profenofos	95,043	3
Prometon	2,000	1
Propachlor	3,705	4
Propanoic acid, 3-[1-[difluoro(1,2,2,2-tetrafluoroethoxy)methyl-1,2,2,2-tetraflu	24,236	1
Pyrene	176,603	4
Q
Quinoline	6,163,383	26
R
Radium, combined (-226 & -228)*	147,878,426	49
Radon*	5,850,081	19
S
sec-Butylbenzene	90,804	8
Selenium	56,100,813	49
Silver	5,936,608	25
Simazine	19,027,204	22
Strontium	261,293,458	50
Strontium-89*	152,959	2
Strontium-90*	11,818,617	9
Styrene	1,133,098	33
T
Tebuconazole	110,378	2
tert-Amyl methyl ether	78	1
tert-Butyl alcohol	2,452,494	3
tert-Butylbenzene	16,562	4
Testosterone	16,853,872	23
Tetrachloroethylene (perchloroethylene)	19,372,015	49
Tetrachloroterephthalic acid	1,137,108	1
Tetradecanoic acid	37,897	1
Tetrahydrofuran	379,502	7
Thallium	9,792,851	40
Titanium	1,137,108	1
Toluene	7,726,065	46
Total PFAS	1,445,387	1
Total trihalomethanes (TTHMs)	296,115,661	50
Toxaphene	298,432	2
Tribromoacetic acid	146,543	1
Tribufos	55,571	2
Trichloroacetic acid	198,501,287	47
Trichloroethylene	18,567,033	43
Trichlorofluoromethane	678,839	10
Trichlorotrifluoroethane	783,956	4
Tritium*	11,834,349	8
U
Uranium, combined (pCi/L)*	80,185,232	45
V
Vanadium	211,898,220	50
Vinyl chloride	1,111,687	22
X
Xylenes (total)	19,651,569	48

* States and population affected are for 2017-2019 except those chemicals marked with an asterisk. For these chemicals, states and population affected range from 2013-2021. Chemicals marked with an * were detected under the EPA's Unregulated Contaminant Monitoring Rule (UCMR 3) program which sampled from 2013-2016, EPA's Unregulated Contamininant Monitoring Rule (UCMR 4) program which sampled from 2018-2021 or are radiological contaminants where testing spans 2014-2019.