Menu

EWG's Tap Water Database — 2019 UPDATE

Donate

Uranium

Marco Island Utilities

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.

 

60

Samples

0

Samples exceeding legal limit (MCL)

0

Samples exceeding
health guidelines

Testing results - average by year

 
YearAverage resultSamples takenDetectionsRange of results
20120.04 pCi/L115ND - 0.15 pCi/L
20130.03 pCi/L94ND - 0.10 pCi/L
2014ND50ND
2015ND120ND
20160.00 pCi/L121ND - 0.02 pCi/L
20170.01 pCi/L111ND - 0.14 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 Result
2012-02-010.13 pCi/L
2012-03-06ND
2012-04-04ND
2012-05-08ND
2012-06-07ND
2012-07-02ND
2012-08-07ND
2012-09-010.04 pCi/L
2012-10-010.15 pCi/L
2012-11-120.08 pCi/L
2012-12-110.04 pCi/L
2013-01-140.10 pCi/L
2013-02-070.06 pCi/L
2013-03-110.09 pCi/L
2013-04-04ND
2013-05-130.04 pCi/L
2013-06-10ND
2013-07-01ND
2013-08-05ND
2013-09-10ND
2014-08-05ND
2014-09-08ND
2014-10-07ND
2014-11-05ND
2014-12-02ND
2015-01-06ND
2015-02-09ND
2015-03-04ND
2015-04-09ND
2015-05-11ND
2015-06-04ND
2015-07-07ND
2015-08-05ND
2015-09-02ND
2015-10-12ND
2015-11-03ND
2015-12-07ND
2016-01-14ND
2016-02-02ND
2016-03-01ND
2016-04-05ND
2016-05-04ND
2016-06-01ND
2016-07-06ND
2016-08-02ND
2016-09-07ND
2016-10-060.02 pCi/L
2016-11-02ND
2016-12-07ND
2017-02-01ND
2017-03-06ND
2017-04-04ND
2017-05-01ND
2017-06-05ND
2017-07-10ND
2017-08-10ND
2017-09-250.14 pCi/L
2017-10-05ND
2017-11-01ND
2017-12-05ND