Selenium

Status: National drinking water standard exists

Selenium is an essential element in diets. But too much selenium can decrease thyroid hormone production and cause hair loss, skin lesions and brittle fingernails.

2017-2019:

FOUND

FOUND ABOVE HEALTH GUIDELINES

FOUND ABOVE LEGAL LIMIT

states detected

5,930

utilities detected

56 million

people served

states over health guideline

utilities over health guideline

34,231

people served over health guideline

states over legal limit

utilities over legal limit

3,048

people served over legal limit

Health concerns for selenium

Hormone disruption

Harm to child development

Harm to the brain and nervous system

Skin damage

State and national drinking water standards and health guidelines

EWG Health Guideline 30 ppb

The EWG Health Guideline of 30 ppb for selenium was defined by the California Office of Environmental Health Hazard Assessment as a public health goal, the level of a drinking water contaminant that does not pose a significant health risk. This health guideline protects against hair loss and nail damage.

EPA Maximum Contaminant
Level (MCL) 50 ppb

The legal limit for selenium, established in 1991, was based on human epidemiological studies of populations exposed to naturally occurring selenium in drinking water. This limit does not include any additional consideration of children’s health.

ppb = parts per billion

States reporting selenium in drinking water

	UTILITIES REPORTING ABOVE HEALTH GUIDELINES			UTILITIES WITH CONTAMINATION
State	Utilities	People Served		Utilities	People Served
Texas		17	13,839			1,015	9,655,632
Florida		0	0			361	7,092,257
California		13	3,164			385	6,300,816
Colorado		5	1,732			517	4,199,116
Utah		0	0			352	3,055,513
Arizona		0	0			91	2,985,476
Kansas		9	1,764			687	2,574,134
Missouri		0	0			72	2,551,868
Nevada		1	110			60	2,284,382
New Jersey		0	0			94	2,019,987
Illinois		0	0			255	1,417,366
New York		0	0			195	1,317,744
Louisiana		0	0			78	1,261,977
Nebraska		6	11,355			214	1,074,476
Oklahoma		1	627			56	981,815
Hawaii		0	0			7	949,743
Virginia		0	0			31	791,065
New Mexico		1	456			172	668,095
Wisconsin		0	0			171	638,838
Delaware		0	0			35	532,186
Kentucky		0	0			77	505,306
Pennsylvania		0	0			94	317,199
Alabama		0	0			23	279,474
Indiana		1	47			47	248,109
Alaska		0	0			10	244,212
Mississippi		0	0			90	237,500
Idaho		0	0			112	208,525
South Dakota		0	0			19	181,010
Washington		0	0			176	179,542
Wyoming		0	0			70	174,157
Michigan		0	0			39	164,433
Connecticut		0	0			11	119,036
Montana		0	0			66	99,896
West Virginia		0	0			38	98,281
Minnesota		0	0			4	83,865
South Carolina		0	0			13	82,507
Georgia		1	871			11	80,916
Iowa		1	266			22	79,295
Rhode Island		0	0			7	78,777
Tennessee		0	0			6	49,425
Ohio		0	0			22	46,781
Arkansas		0	0			12	40,276
Maryland		0	0			16	40,017
North Dakota		0	0			59	34,219
New Hampshire		0	0			7	26,545
Oregon		0	0			19	23,874
North Carolina		0	0			4	15,844
Massachusetts		0	0			4	7,938
Maine		0	0			4	1,368

LESS

Filtering technologies that reduce selenium

Utilities with the highest amounts of selenium, 2017-2019

ALL UTILITIES

LARGE UTILITIES

Utility	Location	Tests	Average level	People served
Valley Estates	Shallowater, TX	11 of 11	107.8 ppb	70
Alpine Springs Mobile Home Park	Palmdale, CA	1 of 2	81.0 ppb	120
Vista Hills Mutual Water Company	Lompoc, CA	3 of 5	78.0 ppb	75
Resthaven Mobile Home Park	Paso Robles, CA	45 of 45	71.5 ppb	75
Heartland House	Lubbock, TX	20 of 22	64.8 ppb	26
Leisure Mountain Mobile Home Park	Tijeras, NM	16 of 16	63.1 ppb	172
Dedham Water Supply	Dedham, IA	13 of 13	56.2 ppb	266
Firth, Village of	Firth, NE	1 of 1	56.0 ppb	600
Burr Oak, City of	Burr Oak, KS	15 of 15	55.5 ppb	159
Fullerton, City of	Fullerton, NE	23 of 23	54.0 ppb	1,352
Beverly, City of	Beverly, KS	6 of 8	53.4 ppb	148
Town North Village Water System	Lubbock, TX	48 of 48	51.4 ppb	360
Glen Elder, City of	Glen Elder, KS	26 of 26	51.0 ppb	433
U.s.n., San Nicolas Island	Point Mugu, CA	9 of 10	50.7 ppb	250
Falfurrias Utility Board	Falfurrias, TX	31 of 31	48.9 ppb	7,500
Ken Mar Gardens	Arroyo Grande, CA	5 of 5	48.8 ppb	84
Wayne, City of	Wayne, NE	9 of 9	48.5 ppb	5,660
Rosa Joint Ventures Water System	Ignacio, NM	15 of 15	47.9 ppb	456
Pecan Grove Mobile Home Park	San Antonio, TX	3 of 3	47.0 ppb	81
Rooks County Rural Water District 1	Woodston, KS	2 of 2	46.0 ppb	55
Sky Ranch Estates	Sandy Valley, NV	7 of 7	45.2 ppb	110
Gove, City of	Gove, KS	6 of 6	44.8 ppb	70
Asgard Subdivision Wa	Silt, CO	26 of 26	44.8 ppb	80
Town North Estates	Lubbock, TX	17 of 17	41.4 ppb	216
Prairie View Ranch WD	Greeley, CO	4 of 4	41.0 ppb	30
Texas Boys Ranch	Lubbock, TX	1 of 1	40.0 ppb	50
Hordville, Village of	Hordville, NE	1 of 1	39.8 ppb	162
Rio Manor Mutual Water Company	Oxnard, CA	4 of 4	39.5 ppb	900
Boone, Town of	Boone, CO	2 of 2	39.0 ppb	350
Maple Water Supply Corporation	Morton, TX	2 of 2	37.5 ppb	50
City of New Home	New Home, TX	2 of 2	37.0 ppb	345
Sutter County Wwd #1 (robbins)	Yuba City, CA	1 of 3	36.7 ppb	350
South Mountain Mutual Water Company	Santa Paula, CA	13 of 13	36.5 ppb	45
City of Wilson	Wilson, TX	20 of 20	36.0 ppb	489
Brainard, Village of	Brainard, NE	18 of 18	36.0 ppb	354
Klondike Independent School District	Lamesa, TX	2 of 2	36.0 ppb	264
Aurora, City of	Aurora, KS	2 of 2	35.5 ppb	55
Geuda Springs, City of	Geuda Springs, KS	2 of 2	35.0 ppb	181
Green River Mutual Water Company	Paso Robles, CA	7 of 7	34.7 ppb	350
Duval County Crd Concepcion	Benavides, TX	2 of 2	34.1 ppb	161
Waverly, City of	Waverly, NE	11 of 11	33.6 ppb	3,227
Dorsett Place	Austin, TX	2 of 2	33.6 ppb	42
Cox Addition Water System	Lubbock, TX	17 of 17	33.2 ppb	114
Morganville, City of	Morganville, KS	1 of 1	32.0 ppb	188
Country View Mobile Home Park	Shallowater, TX	1 of 1	32.0 ppb	55
Kensington, City of	Kensington, KS	9 of 9	31.6 ppb	439
Welch Water Supply Corporation	Welch, TX	2 of 2	31.0 ppb	315
Bogue, City of	Bogue, KS	1 of 1	31.0 ppb	136
City of Morton	Morton, TX	4 of 4	30.8 ppb	2,025
Falfurrias Utility Board Encino	Falfurrias, TX	2 of 2	30.6 ppb	225

Utility	Location	Tests	Average level	People served
Morro Bay PW Department - Water Division	Morro Bay, CA	21 of 22	22.0 ppb	10,327
City of Midland	Midland, TX	10 of 15	20.7 ppb	132,950
City of Hastings*	Hastings, NE	4 of 4	17.9 ppb	25,224
Monroe*	Monroe, MI	1 of 1	16.0 ppb	48,664
City of Davis*	Davis, CA	66 of 104	14.2 ppb	67,298
City of Salina*	Salina, KS	6 of 6	14.2 ppb	46,716
Golden State Water Company - Simi	Los Osos, CA	11 of 12	12.9 ppb	40,638
City of Show Low	Show Low, AZ	33 of 34	12.5 ppb	17,139
St. Johns County Sawgrass Grid*	Ponte Vedra, FL	2 of 4	12.3 ppb	12,133
City of Ocoee	Ocoee, FL	2 of 4	11.2 ppb	34,000
City of Andrews	Andrews, TX	3 of 3	11.0 ppb	11,088
Ventura Waterworks District No. 8 - Simi Valley	Simi Valley, CA	6 of 10	10.8 ppb	86,000
City of Kingsville*	Kingsville, TX	14 of 14	9.96 ppb	29,947
Military Highway WSC - Progreso	Progreso, TX	3 of 4	9.68 ppb	11,136
City of Great Bend	Great Bend, KS	18 of 18	9.58 ppb	15,170
City of Dodge City	Dodge City, KS	28 of 29	8.68 ppb	27,329
City of Liberal	Liberal, KS	16 of 16	8.41 ppb	39,321
City of Brentwood	Brentwood, CA	31 of 41	8.26 ppb	53,278
Oxnard Water Department*	Oxnard, CA	23 of 52	7.90 ppb	200,855
Paso Robles Water Department	Paso Robles, CA	46 of 74	7.57 ppb	30,500
City of Haysville	Haysville, KS	2 of 2	7.55 ppb	11,264
Shawnee County RWD 4C*	Topeka, KS	4 of 4	7.43 ppb	12,000
Pennsville Twsp. Water Depart.	Pennsville, NJ	10 of 11	7.18 ppb	13,500
City of McPherson*	Mcpherson, KS	2 of 2	7.15 ppb	13,077
City of Patterson	Patterson, CA	13 of 14	6.93 ppb	20,560
Santa Paula Water System*	Santa Paula, CA	52 of 63	6.83 ppb	30,048
Montecito Water District	Santa Barbara, CA	5 of 8	6.50 ppb	13,500
City of Hays*	Hays, KS	2 of 2	6.50 ppb	20,852
Buckeye Water District 50	Deville, LA	12 of 28	6.38 ppb	11,700
U.S. Air Force Luke Air Force Base	Luke Afb, AZ	3 of 3	6.33 ppb	10,708
Pueblo West MD	Pueblo West, CO	9 of 9	6.33 ppb	30,000
Moore	Moore, OK	16 of 44	6.28 ppb	55,083
St. Johns County Utilities-Ponte Vedra	Ponte Vedra Beach, FL	1 of 4	6.25 ppb	12,948
Camino Real Regional Utility Authority	Sunland Park, NM	5 of 9	6.19 ppb	17,016
City of Woodland	Woodland, CA	3 of 5	6.12 ppb	56,464
Military Highway WSC - Las Rusias WTP	Progreso, TX	6 of 10	6.06 ppb	14,292
Fillmore Water Department	Fillmore, CA	3 of 5	6.00 ppb	15,222
City of Avondale	Avondale, AZ	24 of 29	5.84 ppb	83,001
Tarpon Springs Water System*	Tarpon Springs, FL	6 of 8	5.84 ppb	30,415
Nueces County WCID 3*	Robstown, TX	5 of 6	5.75 ppb	14,607
Larned State Hospital	Larned, KS	10 of 10	5.72 ppb	11,964
California Water Service Company - Hermosa / Redondo Beach	San Jose, CA	5 of 6	5.72 ppb	95,605
City of Fountain	Fountain, CO	7 of 7	5.64 ppb	29,000
Portales Water System*	Portales, NM	3 of 4	5.55 ppb	14,067
Arizona Water Company - Pinal Valley*	Phoenix, AZ	17 of 19	5.38 ppb	88,019
Northwest Park MUD	Houston, TX	5 of 8	5.38 ppb	17,406
Harris County MUD 168	Sugar Land, TX	4 of 5	5.22 ppb	13,029
West Jordan City Water System	West Jordan, UT	8 of 8	5.08 ppb	113,699
Eagle Mountain City	Eagle Mountain, UT	9 of 9	5.00 ppb	36,000
Epcor Water - Chaparral City	Youngtown, AZ	7 of 8	4.99 ppb	26,026

* This water utility supplies finished drinking water to at least one other water utility. The purchasing utility is not required to test for or report Selenium, but it likely has the contaminant in its water supply.