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.
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 |
Filtering technologies that reduce selenium
Reverse Osmosis
Utilities with the highest amounts of selenium, 2017-2019
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.