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EWG's Tap Water Database — 2019 UPDATE

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Uranium

Sacramento Suburban Water District

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.

 

49

Samples

0

Samples exceeding legal limit (MCL)

7

Samples exceeding
health guidelines

Testing results - average by year

 
YearAverage resultSamples takenDetectionsRange of results
2012ND50ND
2013ND50ND
20140.46 pCi/L335ND - 3.40 pCi/L
20151.35 pCi/L21ND - 2.70 pCi/L
2016ND20ND
20170.54 pCi/L21ND - 1.08 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
2012-01-115810-240-1330ND
2012-04-115810-240-1330ND
2012-07-025810-240-1310ND
2012-08-075810-013-1345ND
2012-10-035810-240-0950ND
2013-01-105810-240-1140ND
2013-07-255810-246-1050ND
2013-08-215810-013-1150ND
2013-09-265810-244-1255ND
2013-10-165810-246-1000ND
2014-01-275810-246-1005ND
2014-04-285810-244-1200ND
2014-06-175810-246-1115ND
2014-06-195810-004-1105ND
2014-06-195810-064-1120ND
2014-06-195810-061-09503.20 pCi/L
2014-06-195810-062-1000ND
2014-07-015810-034-09203.30 pCi/L
2014-07-085810-042-1030ND
2014-07-085810-015-1000ND
2014-07-095810-007-1325ND
2014-07-095810-052-1130ND
2014-07-105810-033-1150ND
2014-07-155810-018-1030ND
2014-07-165810-074-11553.20 pCi/L
2014-07-165810-066-0915ND
2014-07-165810-035-1100ND
2014-07-175810-051-1100ND
2014-07-175810-071-1020ND
2014-07-175810-054-13002.00 pCi/L
2014-07-175810-019-1150ND
2014-07-235810-013-1230ND
2014-07-245810-065-1115ND
2014-07-245810-020-1330ND
2014-07-295810-032-1130ND
2014-08-115810-246-1235ND
2014-08-215810-069-10303.40 pCi/L
2014-08-215810-028-1345ND
2014-08-215810-012-1200ND
2014-08-215810-010-1115ND
2014-08-215810-244-0945ND
2014-08-275810-017-1045ND
2014-10-155810-244-0930ND
2015-01-155810-244-1140ND
2015-03-255810-101-09402.70 pCi/L
2016-10-260010-248-1400ND
2016-11-145867-250-1200ND
2017-01-154470-248-14201.08 pCi/L
2017-04-184470-248-1300ND