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.

2015-2017:

FOUND

FOUND ABOVE HEALTH GUIDELINES

FOUND ABOVE LEGAL LIMIT

states detected

6,046

utilities detected

66 million

people served

states over health guideline

utilities over health guideline

21,572

people served over health guideline

states over legal limit

utilities over legal limit

3,556

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		22	13,491			1,583	16,566,017
California		11	2,409			387	10,920,175
Florida		0	0			514	8,269,001
Colorado		4	518			388	3,292,477
Arizona		0	0			68	2,791,899
Utah		0	0			345	2,775,934
Missouri		0	0			77	2,584,995
Kansas		10	2,471			647	2,382,709
Nevada		1	110			46	2,048,112
Louisiana		0	0			108	1,723,552
Pennsylvania		4	264			115	1,534,755
Hawaii		0	0			6	963,268
Oklahoma		0	0			64	952,300
Nebraska		0	0			9	883,441
New Jersey		0	0			91	876,071
New York		1	1,100			168	843,244
Wisconsin		0	0			157	712,345
New Mexico		3	485			199	633,073
Kentucky		0	0			81	608,612
Illinois		1	221			138	585,364
Washington		0	0			129	497,863
Delaware		0	0			25	471,013
Massachusetts		0	0			16	285,189
Alabama		0	0			20	282,228
Indiana		1	47			48	245,967
Mississippi		0	0			64	218,518
Michigan		0	0			6	196,697
South Dakota		0	0			20	189,554
North Dakota		0	0			37	180,465
Connecticut		0	0			16	174,042
Wyoming		0	0			94	150,113
West Virginia		0	0			65	146,711
Maryland		0	0			21	101,615
South Carolina		0	0			13	99,968
Iowa		1	266			54	99,094
Tennessee		0	0			9	95,989
Minnesota		0	0			2	65,041
Virginia		0	0			32	48,100
Montana		0	0			85	43,773
Arkansas		0	0			9	35,968
Ohio		0	0			16	31,755
Georgia		1	122			6	29,158
Idaho		0	0			18	28,206
North Carolina		1	68			10	21,804
Rhode Island		0	0			4	10,431
New Hampshire		0	0			19	4,990
Oregon		0	0			12	4,586
Maine		0	0			4	2,210
Alaska		0	0			1	53

LESS

Filtering technologies that reduce selenium

Utilities with the highest amounts of selenium, 2015-2017

ALL UTILITIES

LARGE UTILITIES

Utility	Location	Tests	Average level	People served
Alpine Springs Mobile Home Park	Palmdale, CA	1 of 1	162.0 ppb	120
Sunnyside Farms Mutual Water Company	Palmdale, CA	1 of 1	107.0 ppb	326
Valley Estates	Shallowater, TX	7 of 7	106.0 ppb	70
Heartland House	Lubbock, TX	11 of 12	85.2 ppb	26
Burr Oak, City of	Burr Oak, KS	6 of 6	61.2 ppb	168
U.s.n., San Nicolas Island	Point Mugu, CA	5 of 6	60.8 ppb	250
Vista Hills Mutual Water Company	Lompoc, CA	1 of 2	60.0 ppb	75
Montclair Condominiums	Poughkeepsie, NY	1 of 1	60.0 ppb	1,100
Sutter County Wwd #1 (robbins)	Yuba City, CA	1 of 2	55.0 ppb	350
Leisure Mountain Mobile Home Park	Tijeras, NM	11 of 11	54.8 ppb	162
Dana Ranch	Emeryville, CA	1 of 1	53.0 ppb	34
South Mountain Mutual Water Company	Santa Paula, CA	5 of 5	52.4 ppb	45
Glen Elder, City of	Glen Elder, KS	13 of 13	51.8 ppb	435
Sky Ranch Estates	Sandy Valley, NV	4 of 4	51.2 ppb	110
Rosa Joint Ventures Water System	Ignacio, NM	6 of 6	50.5 ppb	210
Resthaven Mobile Home Park	Paso Robles, CA	23 of 23	50.3 ppb	75
Falfurrias Utility Board	Falfurrias, TX	16 of 16	49.8 ppb	7,500
Ken Mar Gardens	Arroyo Grande, CA	4 of 4	49.5 ppb	84
Riverview Communities Lp South	Warren, PA	1 of 1	48.2 ppb	100
Town North Village Water System	Lubbock, TX	24 of 24	48.1 ppb	335
Rio Manor Mutual Water Company	Oxnard, CA	2 of 2	48.0 ppb	900
Dedham Water Supply	Dedham, IA	4 of 4	47.5 ppb	266
Beverly, City of	Beverly, KS	2 of 3	46.7 ppb	159
Rooks County Rural Water District 1	Woodston, KS	1 of 1	45.0 ppb	87
King Ranch Laureles Division	Kingsville, TX	1 of 1	44.8 ppb	60
Asgard Subdivision Wa	Silt, CO	13 of 13	44.0 ppb	80
Pecan Grove Mobile Home Park	San Antonio, TX	1 of 1	44.0 ppb	81
Catarina Water Supply Corporation	Carrizo Springs, TX	1 of 1	43.4 ppb	252
Heritage Park Apartments	Lafayette, IN	1 of 1	42.0 ppb	47
Whippoorwill Subdivision	Valdosta, GA	1 of 1	41.0 ppb	122
Texas Boys Ranch	Lubbock, TX	1 of 1	40.0 ppb	50
Floyd Ws Village of	Floyd, NM	1 of 1	40.0 ppb	113
City of New Home	New Home, TX	1 of 1	40.0 ppb	334
Aurora, City of	Aurora, KS	1 of 1	40.0 ppb	60
Town North Estates	Lubbock, TX	12 of 12	39.8 ppb	210
City of Wilson	Wilson, TX	13 of 13	38.1 ppb	485
Welch Water Supply Corporation	Welch, TX	1 of 1	38.0 ppb	315
Ankrom Acres Mobile Home Park	Clinton, PA	1 of 1	38.0 ppb	24
Wimberley Oaks Water Supply Corporation	Wimberley, TX	1 of 1	37.4 ppb	69
Klondike Independent School District	Lamesa, TX	1 of 1	37.0 ppb	264
Chandlers Valley Mobile Home Park	Sheffield, PA	1 of 1	36.4 ppb	50
Fox Creek Farms Water Company	Brimfield, IL	1 of 1	36.0 ppb	221
Spring Meadow Mobile Home Park	Midland, TX	1 of 1	36.0 ppb	163
Riviera WCID	Riviera, TX	1 of 1	35.1 ppb	729
Prairie View Ranch WD	Greeley, CO	2 of 2	35.0 ppb	30
Bentley, City of	Bentley, KS	1 of 1	35.0 ppb	524
Geuda Springs, City of	Geuda Springs, KS	1 of 1	35.0 ppb	183
Greenleaf, City of	Greenleaf, KS	1 of 1	34.0 ppb	314
Pithole Water Association	Cyclone, PA	1 of 1	33.5 ppb	90
Dorsett Place	Austin, TX	1 of 1	33.3 ppb	42

Utility	Location	Tests	Average level	People served
City of Midland	Midland, TX	11 of 15	25.1 ppb	132,950
City of Ocoee	Ocoee, FL	2 of 2	22.4 ppb	39,239
Buckeye Water District 50	Deville, LA	10 of 10	17.7 ppb	10,287
City of Davis*	Davis, CA	40 of 59	16.0 ppb	67,298
Monroe*	Monroe, MI	1 of 1	16.0 ppb	48,726
City of Salina*	Salina, KS	3 of 3	13.7 ppb	47,867
Morro Bay PW Department - Water Division	Morro Bay, CA	8 of 8	13.0 ppb	10,327
Ventura Waterworks District No. 8 - Simi Valley	Simi Valley, CA	3 of 4	12.0 ppb	86,000
City of Andrews	Andrews, TX	2 of 2	12.0 ppb	11,088
Camarillo Water Department	Camarillo, CA	1 of 1	12.0 ppb	45,500
City of Show Low	Show Low, AZ	12 of 13	11.6 ppb	17,139
Montecito Water District	Santa Barbara, CA	4 of 4	10.8 ppb	13,500
Shawnee County RWD 4C*	Topeka, KS	2 of 2	10.6 ppb	12,000
City of Woodland	Woodland, CA	3 of 3	10.2 ppb	56,464
Kingman Municipal Water	Kingman, AZ	7 of 7	9.91 ppb	45,000
City of Kingsville*	Kingsville, TX	6 of 6	9.13 ppb	32,736
City of Great Bend	Great Bend, KS	9 of 9	8.70 ppb	15,840
City of Haysville	Haysville, KS	1 of 1	8.50 ppb	11,112
City of Brentwood	Brentwood, CA	15 of 21	8.12 ppb	53,278
City of Liberal	Liberal, KS	8 of 8	7.58 ppb	21,012
City of Dodge City	Dodge City, KS	13 of 14	7.41 ppb	28,117
California Water Service Company - Hermosa / Redondo Beach	San Jose, CA	1 of 1	7.40 ppb	95,605
Arizona Water Company - Pinal Valley*	Phoenix, AZ	9 of 9	7.18 ppb	88,019
Fillmore Water Department	Fillmore, CA	2 of 3	7.00 ppb	15,222
Horizon Regional MUD	Horizon City, TX	2 of 2	7.00 ppb	32,088
Northwest Park MUD	Houston, TX	3 of 4	6.90 ppb	17,406
St. Lucie West Utilities*	Port St. Lucie, FL	1 of 1	6.70 ppb	16,795
City of Hays*	Hays, KS	1 of 1	6.70 ppb	21,044
Waialua	Honolulu, HI	1 of 1	6.70 ppb	13,447
City of Patterson	Patterson, CA	7 of 7	6.57 ppb	20,560
Nueces County WCID 3*	Robstown, TX	3 of 3	6.40 ppb	14,607
City of McPherson*	Mcpherson, KS	1 of 1	6.40 ppb	13,189
Santa Paula Water System*	Santa Paula, CA	24 of 29	6.34 ppb	30,048
City of Fredericksburg	Fredericksburg, TX	4 of 4	6.13 ppb	14,500
Eagle Mountain City	Eagle Mountain, UT	4 of 4	6.05 ppb	24,000
City of Fountain	Fountain, CO	2 of 2	5.70 ppb	21,000
Military Highway WSC - Progreso	Progreso, TX	2 of 2	5.55 ppb	11,136
Avalon Water and Sewerage Utilities	Avalon, NJ	5 of 5	5.46 ppb	39,839
Oxnard Water Department	Oxnard, CA	9 of 31	5.44 ppb	200,855
Harris County FWSD 61*	Houston, TX	5 of 6	5.40 ppb	17,586
City of Newton*	Newton, KS	1 of 1	5.30 ppb	19,120
Moore	Moore, OK	10 of 23	5.12 ppb	41,138
Metropolitan Utilities District*	Omaha, NE	1 of 1	5.12 ppb	600,000
City of Beeville*	Beeville, TX	3 of 3	5.10 ppb	15,039
Paso Robles Water Department	Paso Robles, CA	22 of 41	5.09 ppb	30,500
City of Garden City*	Garden City, KS	3 of 4	5.05 ppb	27,004
Epcor Water - Chaparral City	Youngtown, AZ	2 of 2	5.00 ppb	26,026
Jackson*	Jackson, MI	1 of 1	5.00 ppb	33,961
Cal American Water Company	Newbury Park, CA	17 of 24	4.92 ppb	61,206
California Water Service Company - Westlake	San Jose, CA	17 of 24	4.92 ppb	19,451

* 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.