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EWG's Tap Water Database — 2021 UPDATE

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Uranium

Chocorua Meadows

Uranium is a known human carcinogen. The federal legal limit for uranium is set at 30 micrograms per liter (corresponding to parts per billion), but utilities can also report uranium in picocuries per liter (pCi/L), which is a measure of radioactivity in water. EWG translated all uranium results to pCi/L using a conversion factor developed by the EPA. With this conversion approach, the limit of 30 ppb corresponds to 20 pCi/L. Drinking water with this much uranium would cause more than 4.6 cancer cases in a population of 100,000. California set a public health goal for uranium of 0.43 pCi/L. Read More.

Multiple forms of uranium can be detected in water, including uranium-234, uranium-235 and uranium-238. Uranium-234 is the most toxic form of uranium for human health.

MORE ABOUT THIS CONTAMINANT

 

108

Samples

0

Samples exceeding legal limit (MCL)

2

Samples exceeding
health guidelines

Testing results - average by year

 
YearAverage resultSamples takenDetectionsRange of results
2014ND220ND
2015N/A00N/A
20160.70 pCi/L221ND - 15.41 pCi/L
2017ND210ND
2018ND210ND
20190.40 pCi/L221ND - 8.71 pCi/L

pCi/L = picocuries per liter

State and national drinking water standards and health guidelines

EWG Health Guideline 0.43 pCi/L

The EWG Health Guideline of 0.43 pCi/L for uranium 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. Three most common uranium isotopes are U-234, U-235 and U-238. All isotopes of uranium are radioactive, and the total radioactivity depends on the ratio of isotopes. This health guideline protects against cancer.

EPA Maximum Contaminant
Level (MCL) 20 pCi/L

pCi/L = picocuries per liter

All test results

Date Lab ID Result
2014-06-08A403386001ND
2014-12-13A409746003ND
2014-12-13A409746014ND
2014-12-14A409746005ND
2014-12-14A409746006ND
2014-12-14A409746009ND
2014-12-14A409746011ND
2014-12-14A409746012ND
2014-12-14A409746013ND
2014-12-14A409746015ND
2014-12-14A409746016ND
2014-12-14A409746017ND
2014-12-14A409746018ND
2014-12-14A409746020ND
2014-12-14A409746021ND
2014-12-15A409746001ND
2014-12-15A409746002ND
2014-12-15A409746004ND
2014-12-15A409746007ND
2014-12-15A409746008ND
2014-12-15A409746010ND
2014-12-15A409746019ND
2016-08-2321608099715.41 pCi/L
2016-12-04B610684001ND
2016-12-04B610684002ND
2016-12-04B610684003ND
2016-12-04B610684004ND
2016-12-04B610684005ND
2016-12-04B610684006ND
2016-12-04B610684007ND
2016-12-04B610684008ND
2016-12-04B610684009ND
2016-12-04B610684010ND
2016-12-04B610684011ND
2016-12-04B610684012ND
2016-12-04B610684014ND
2016-12-04B610684015ND
2016-12-04B610684016ND
2016-12-04B610684017ND
2016-12-04B610684019ND
2016-12-04B610684020ND
2016-12-04B610684021ND
2016-12-05B610684013ND
2016-12-05B610684018ND
2017-12-03B710269007ND
2017-12-03B710269008ND
2017-12-03B710269009ND
2017-12-03B710269010ND
2017-12-03B710269011ND
2017-12-03B710269012ND
2017-12-03B710269013ND
2017-12-03B710269014ND
2017-12-03B710269015ND
2017-12-03B710269016ND
2017-12-03B710269017ND
2017-12-03B710269018ND
2017-12-03B710269019ND
2017-12-03B710269020ND
2017-12-04B710269001ND
2017-12-04B710269002ND
2017-12-04B710269003ND
2017-12-04B710269004ND
2017-12-04B710269005ND
2017-12-04B710269006ND
2017-12-04B710269021ND
2018-12-08B810042002ND
2018-12-08B810042003ND
2018-12-08B810042004ND
2018-12-08B810042006ND
2018-12-08B810042009ND
2018-12-08B810042010ND
2018-12-08B810042011ND
2018-12-08B810042012ND
2018-12-08B810042013ND
2018-12-08B810042014ND
2018-12-08B810042015ND
2018-12-08B810042016ND
2018-12-08B810042017ND
2018-12-08B810042018ND
2018-12-08B810042020ND
2018-12-09B810042001ND
2018-12-09B810042005ND
2018-12-09B810042007ND
2018-12-09B810042008ND
2018-12-09B810042019ND
2018-12-09B810042021ND
2019-08-07219080364.018.71 pCi/L
2019-12-15B910771001ND
2019-12-15B910771002ND
2019-12-15B910771003ND
2019-12-15B910771010ND
2019-12-15B910771011ND
2019-12-15B910771012ND
2019-12-15B910771013ND
2019-12-15B910771014ND
2019-12-15B910771015ND
2019-12-15B910771016ND
2019-12-15B910771017ND
2019-12-15B910771018ND
2019-12-15B910771019ND
2019-12-16B910771004ND
2019-12-16B910771005ND
2019-12-16B910771006ND
2019-12-16B910771007ND
2019-12-16B910771008ND
2019-12-16B910771009ND
2019-12-16B910771020ND
2019-12-16B910771021ND