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EWG's Tap Water Database — 2021 UPDATE

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Arsenic

Cottonwood Municipal Water Cw1

Arsenic is a potent carcinogen and common contaminant in drinking water. Arsenic causes thousands of cases of cancer each year in the U.S. Click here to read more about arsenic.

 

122

Samples

6

Samples exceeding legal limit (MCL)

104

Samples exceeding
health guidelines

Testing results - average by year

 
YearAverage resultSamples takenDetectionsRange of results
2013N/A00N/A
20144.14 ppb1612ND - 6.70 ppb
20153.47 ppb1811ND - 8.10 ppb
20164.12 ppb1814ND - 7.80 ppb
20174.61 ppb2120ND - 8.10 ppb
20185.95 ppb2221ND - 9.30 ppb
20197.12 ppb2726ND - 14.0 ppb

ppb = parts per billion

State and national drinking water standards and health guidelines

EWG Health Guideline 0.004 ppb

The EWG Health Guideline of 0.004 ppb for arsenic 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 cancer.

EPA Maximum Contaminant
Level (MCL) 10 ppb

The legal limit for arsenic, established in 2001, was based on costs for arsenic removal, as calculated at the time that the standard was set. This limit does not fully protect against the risk of cancer due to arsenic exposure.

ppb = parts per billion

All test results

Date Lab ID Result
2014-02-25550-21164-14.90 ppb
2014-02-25550-21164-25.20 ppb
2014-02-25550-21164-3ND
2014-02-25550-21164-5ND
2014-05-14550-24841-26.60 ppb
2014-05-14550-24841-36.70 ppb
2014-05-14550-24841-45.20 ppb
2014-05-16550-24841-54.00 ppb
2014-08-05550-29739-106.10 ppb
2014-08-05550-29739-116.30 ppb
2014-08-05550-29739-7ND
2014-08-05550-29739-96.00 ppb
2014-11-17550-35675-13.50 ppb
2014-11-17550-35675-2ND
2014-11-17550-35675-35.30 ppb
2014-11-17550-35675-46.50 ppb
2015-02-06550-40571-16ND
2015-02-06550-40571-17ND
2015-02-06550-40571-185.30 ppb
2015-02-06550-40571-196.70 ppb
2015-05-10550-44906-14.60 ppb
2015-05-10550-44906-28.00 ppb
2015-05-10550-44906-34.90 ppb
2015-05-10550-44906-5ND
2015-06-03201506040073I7.20 ppb
2015-06-03201506040076I1.000 ppb
2015-08-26550-50622-78.10 ppb
2015-08-26550-50622-85.70 ppb
2015-08-26550-50622-9ND
2015-09-03550-50985-1ND
2015-11-20550-54893-166.50 ppb
2015-11-20550-54893-174.40 ppb
2015-11-20550-54893-18ND
2015-11-20550-54893-19ND
2016-02-05550-58921-17.60 ppb
2016-02-05550-58921-43.40 ppb
2016-02-11550-58925-2ND
2016-03-02550-59755-17.80 ppb
2016-05-09550-63401-1ND
2016-05-12550-63534-1ND
2016-05-12550-63534-26.60 ppb
2016-05-12550-63534-37.00 ppb
2016-08-15550-68480-42.30 ppb
2016-08-15550-68480-55.20 ppb
2016-08-15550-68480-65.10 ppb
2016-08-19550-68481-15.50 ppb
2016-09-01550-69039-15.60 ppb
2016-11-22550-73666-56.40 ppb
2016-12-01550-73863-21.60 ppb
2016-12-01550-73863-33.70 ppb
2016-12-01550-73863-5ND
2016-12-01550-73863-66.30 ppb
2017-02-15550-78043-16.00 ppb
2017-02-15550-78043-22.10 ppb
2017-02-15550-78043-3ND
2017-02-17550-78043-106.20 ppb
2017-02-17550-78043-94.90 ppb
2017-03-14201703150222I6.60 ppb
2017-05-20550-84208-102.60 ppb
2017-05-20550-84208-114.30 ppb
2017-05-20550-84208-127.80 ppb
2017-05-22550-84226-11.20 ppb
2017-06-08550-84225-14.50 ppb
2017-09-06550-89413-81.10 ppb
2017-09-07550-89413-68.10 ppb
2017-09-07550-89413-72.60 ppb
2017-09-12550-90024-15.60 ppb
2017-09-12550-90024-25.30 ppb
2017-12-02550-94107-13.30 ppb
2017-12-02550-94107-142.20 ppb
2017-12-02550-94107-37.50 ppb
2017-12-02550-94107-47.40 ppb
2017-12-02550-94107-57.50 ppb
2018-03-02550-99334-6ND
2018-03-17550-99767-18.00 ppb
2018-03-17550-99767-25.20 ppb
2018-03-18550-99767-37.90 ppb
2018-03-18550-99767-47.40 ppb
2018-05-16201805170466I2.20 ppb
2018-05-16201805170467I7.40 ppb
2018-06-07550-104646-127.60 ppb
2018-06-09550-104646-134.10 ppb
2018-06-09550-104646-146.20 ppb
2018-06-09550-104646-152.20 ppb
2018-06-20550-104964-19.30 ppb
2018-09-03550-109529-26.00 ppb
2018-09-03550-109529-38.50 ppb
2018-09-03550-109529-41.60 ppb
2018-09-03550-109529-56.40 ppb
2018-09-03550-109529-65.90 ppb
2018-12-06L1053064-021.72 ppb
2018-12-06L1053064-078.51 ppb
2018-12-13L1054569-179.15 ppb
2018-12-13L1054569-187.13 ppb
2018-12-14L1054569-198.49 ppb
2019-03-06L1079609-201.35 ppb
2019-03-07L1079609-1710.2 ppb
2019-03-07L1079609-187.56 ppb
2019-03-07L1079609-196.80 ppb
2019-03-09L1079609-25ND
2019-03-2619C2772-0112.0 ppb
2019-05-2619E2963-022.60 ppb
2019-06-0519F1230-016.50 ppb
2019-06-0519F1230-028.30 ppb
2019-06-1819F2006-019.00 ppb
2019-06-2519F2691-0112.0 ppb
2019-07-0819G1080-0114.0 ppb
2019-08-2819I0489-032.90 ppb
2019-08-3019I0489-042.40 ppb
2019-09-0819I1156-018.00 ppb
2019-09-0819I1156-027.60 ppb
2019-09-0819I1156-036.70 ppb
2019-11-13201911140247I8.20 ppb
2019-11-13201911140248I1.80 ppb
2019-11-13201911140249I6.90 ppb
2019-11-13201911140250I12.0 ppb
2019-12-0419L1261-012.60 ppb
2019-12-0419L1261-028.50 ppb
2019-12-0419L1261-038.40 ppb
2019-12-0419L1261-045.00 ppb
2019-12-0419L1261-0511.0 ppb
2019-12-05201912060116I9.90 ppb