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EWG's Tap Water Database — 2019 UPDATE

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Radium, combined (-226 & -228)

City of Mesa

Radium is a radioactive element that causes bone cancer and other cancers. It can occur naturally in groundwater, and oil and gas extraction activities such as hydraulic fracturing can elevate concentrations. Read More.

Radium releases radioactive particles that harm health in many ways, causing tumors in bone, lungs and other organs; leukemia; and skin and blood damage. Water utilities typically report radium amounts in picocuries per liter (pCi/L), which is a measure of radioactivity in water. The two most common forms of radium are radium-226 and radium-228. They may be reported separately or together.

Federal law allows up to 5 picocuries per liter of combined radium-226 and radium-228 in tap water. Research by the U.S. Geological Survey shows that in some regions of the country, such as the mid-continental region and North Atlantic coastal region, more than 20 percent of sampled wells have radium in levels exceeding the federal drinking water limit. And the legal limit does not equate safety: The EPA estimates that one in every 10,000 people drinking water containing radium at this level would develop cancer over a lifetime.

California set a public health goal much lower than the federal limit – 0.05 picocuries per liter of radium-226 and 0.019 picocuries per liter of radium-228, concentrations that are lower than the detection limit for most water tests.

Click here to read more on radiological contaminants.

 

70

Samples

0

Samples exceeding legal limit (MCL)

3

Samples exceeding
health guidelines

Testing results - average by year

 
YearAverage resultSamples takenDetectionsRange of results
2012ND430ND
20130.12 pCi/L51ND - 0.60 pCi/L
2014ND20ND
20150.04 pCi/L141ND - 0.60 pCi/L
2016N/A00N/A
20170.08 pCi/L61ND - 0.50 pCi/L

pCi/L = picocuries per liter

State and national drinking water standards and health guidelines

EWG Health Guideline 0.05 pCi/L

EWG applied the health guideline of 0.05 pCi/L, defined by the California Office of Environmental Health Hazard Assessment as a public health goal for radium-226, to radium-226 and radium-228 combined. This health guideline protects against cancer.

EPA Maximum Contaminant
Level (MCL) 5 pCi/L

The legal limit for combined radium-226 and radium-228, established in 1976, was based on costs for radium removal, as calculated at the time that the standard was set. This limit does not fully protect against the risk of cancer due to radium exposure.

pCi/L = picocuries per liter

All test results

Date Lab ID Result
2012-01-12RSE43313ND
2012-01-18RSE43346ND
2012-01-18RSE43345ND
2012-01-18RSE43344ND
2012-01-18RSE43343ND
2012-01-19RSE43361ND
2012-01-19RSE43360ND
2012-01-19RSE43359ND
2012-01-23RSE43384ND
2012-01-23RSE43383ND
2012-01-23RSE43382ND
2012-01-23RSE43381ND
2012-01-23RSE43380ND
2012-01-24RSE43392ND
2012-01-24RSE43393ND
2012-01-24RSE43395ND
2012-01-24RSE43394ND
2012-03-06RSE43676ND
2012-03-06RSE43675ND
2012-03-06RSE43674ND
2012-03-06RSE43673ND
2012-03-07RSE43691ND
2012-03-07RSE43692ND
2012-03-07RSE43693ND
2012-03-07RSE43694ND
2012-04-09RSE43876ND
2012-04-16RSE43917ND
2012-04-16RSE43916ND
2012-04-17RSE43927ND
2012-04-17RSE43926ND
2012-04-17RSE43925ND
2012-05-07RSE44099ND
2012-05-08RSE44100ND
2012-06-20RSE44345ND
2012-08-08RSE44701ND
2012-08-15RSE44751ND
2012-08-22RSE44777ND
2012-08-27RSE44839ND
2012-08-27RSE44838ND
2012-08-28RSE44845ND
2012-11-19RSE45337ND
2012-11-20RSE45346ND
2012-11-20RSE45348ND
2013-03-05RSE45941ND
2013-03-05RSE45940ND
2013-05-09RSE46435ND
2013-07-16RSE46861ND
2013-10-15RSE476020.60 pCi/L
2014-02-12RSE48464ND
2014-04-14RSE49018ND
2015-02-04RSE51130ND
2015-02-09RSE51168ND
2015-02-11RSE51177ND
2015-04-01RSE51494ND
2015-04-14RSE51577ND
2015-04-21RSE51641ND
2015-07-07RSE52208ND
2015-07-14RSE52248ND
2015-07-21RSE52295ND
2015-10-06RSE528870.60 pCi/L
2015-10-14RSE52985ND
2015-10-21RSE53060ND
2015-11-03RSE53168ND
2015-11-03RSE53167ND
2017-06-15RSE58378ND
2017-06-28RSE58476ND
2017-08-16RSE589200.50 pCi/L
2017-08-16RSE58919ND
2017-11-28RSE59622ND
2017-11-28RSE59623ND