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EWG's Tap Water Database — 2021 UPDATE

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Tetrachloroethylene (perchloroethylene)

Dean Water Supply Corporation

Dry cleaning chemical tetrachloroethylene, or perc, can cause cancer. It pollutes soil and groundwater due to emissions from dry cleaning facilities, and automotive, metalworking and other industries. Read More.

The EPA considers tetrachloroethylene a likely human carcinogen. It has been linked with increased incidence of lung, breast and colon cancers. Tetrachloroethylene also damages the liver, kidneys and central nervous system. The California public health goal of 0.06 parts per billion, set to protect against cancer, is 80 times lower than the amount allowed by the federal government, which is a Maximum Contaminant Level of 5 parts per billion.

Click here to read more about carcinogenic VOCs.

 

17

Samples

0

Samples exceeding legal limit (MCL)

0

Samples exceeding
health guidelines

Testing results - average by year

 
YearAverage resultSamples takenDetectionsRange of results
2014ND10ND
2015ND40ND
2016ND30ND
2017ND30ND
2018ND30ND
2019ND30ND

ppb = parts per billion

State and national drinking water standards and health guidelines

EWG Health Guideline 0.06 ppb

The EWG Health Guideline of 0.06 ppb for tetrachloroethylene 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) 5 ppb

The legal limit for tetrachloroethylene, established in 1991, was based on analytical detection limits at the time that the standard was set. This limit does not fully protect against the risk of cancer due to tetrachloroethylene exposure.

ppb = parts per billion

All test results

Date Lab ID Result
2014-12-19Q1460754007ND
2015-07-02AC98352ND
2015-12-02Q1547859006ND
2015-12-02Q1547859003ND
2015-12-02Q1547859002ND
2016-10-17Q1644288006ND
2016-10-17Q1644288003ND
2016-10-17Q1644288002ND
2017-08-30Q1739978013ND
2017-08-30Q1739978021ND
2017-08-30Q1739978016ND
2018-08-01Q1830513008ND
2018-08-01Q1830513002ND
2018-08-01Q1830513006ND
2019-08-08Q1952672002ND
2019-08-08Q1952672006ND
2019-08-08Q1952672004ND