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EWG's Tap Water Database — 2019 UPDATE

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Tetrachloroethylene (perchloroethylene)

San Francisco Regional Water System

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.

 

14

Samples

0

Samples exceeding legal limit (MCL)

0

Samples exceeding
health guidelines

Testing results - average by year

 
YearAverage resultSamples takenDetectionsRange of results
2012ND10ND
2013ND30ND
2014ND20ND
2015ND20ND
2016ND30ND
2017ND30ND

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
2012-06-139590-001-1045ND
2013-06-189553-016-0936ND
2013-06-189553-001-1110ND
2013-10-079553-015-1024ND
2014-06-179553-016-0904ND
2014-06-179553-001-1130ND
2015-05-279553-001-1235ND
2015-06-189553-015-0915ND
2016-06-149553-015-1231ND
2016-06-149553-001-1105ND
2016-06-219553-016-1055ND
2017-06-199553-015-1100ND
2017-06-199553-001-1025ND
2017-06-199553-016-0953ND