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EWG's Tap Water Database — 2021 UPDATE

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Chromium (total)

San Francisco Regional Water System

Chromium is a naturally occurring metal, but industrial uses can elevate its levels in water. One form, hexavalent chromium, causes cancer. Total chromium is not a good indicator of the amount of hexavalent chromium in drinking water.

 

16

Samples

0

Samples exceeding legal limit (MCL)

0

Samples exceeding
health guidelines

Testing results - average by year

 
YearAverage resultSamples takenDetectionsRange of results
2014ND30ND
2015ND30ND
2016ND30ND
2017ND30ND
2018ND20ND
2019ND20ND

ppb = parts per billion

State and national drinking water standards and health guidelines

EPA Maximum Contaminant
Level (MCL) 100 ppb

The legal limit for total chromium, established in 1991, was based on a 1958 toxicity study in laboratory animals, and applies to both the less-toxic trivalent chromium and the more-toxic hexavalent chromium forms of this compound. This limit does not protect against the risk of cancer from ingestion of hexavalent chromium.

ppb = parts per billion

All test results

Date Lab ID Result
2014-06-179553-001-1130ND
2014-06-179553-016-0904ND
2014-09-169553-015-1035ND
2015-05-279553-001-1235ND
2015-05-279553-016-0830ND
2015-06-189553-015-0915ND
2016-06-149553-001-1105ND
2016-06-149553-015-1231ND
2016-06-219553-016-1055ND
2017-06-199553-001-1025ND
2017-06-199553-015-1100ND
2017-06-199553-016-0953ND
2018-06-189553-016-1100ND
2018-06-289553-015-0950ND
2019-06-179553-001-1012ND
2019-07-029553-016-0900ND