Styrene

Oblates of St. Francis

Styrene is a volatile cancer-causing chemical used for manufacturing Styrofoam (polystyrene) and other plastics. Releases from industrial production sites and hazardous waste landfills cause styrene contamination in drinking water. Read More.

In addition to increasing the risk of cancer, styrene can also damage the liver and the nervous system. California set a public health goal for styrene in drinking water at 0.5 parts per billion. The federal Maximum Contaminant Level (MCL) allows up to 100 parts per billion of styrene in water, which is 200 times more than the California recommended level.

Click here to read more about carcinogenic VOCs.

MORE ABOUT THIS CONTAMINANT

Samples

Samples exceeding legal limit (MCL)

Samples exceeding
health guidelines

Testing results - average by year

Year	Average result	Samples taken	Range of results
2014	ND	4	ND
2015	ND	4	ND
2016	ND	1	ND
2017	ND	1	ND
2018	N/A	0	N/A
2019	N/A	0	N/A

ppb = parts per billion

State and national drinking water standards and health guidelines

EWG Health Guideline 0.5 ppb

The EWG Health Guideline of 0.5 ppb for styrene 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) 100 ppb

The legal limit for styrene, established in 1991, was based on a toxicity study in laboratory animals conducted in the 1970s. This limit may not fully protect against the risk of cancer due to styrene exposure.

ppb = parts per billion

All test results

Date	Lab ID	Result
2014-02-25	1071359_01_03819	ND
2014-04-04	1071359_01_04372	ND
2014-07-11	1071359_01_00013	ND
2014-11-03	1071359_01_00166	ND
2015-01-15	1071359_01_00220	ND
2015-05-14	E15003550001	ND
2015-07-01	E16000018001	ND
2015-10-01	E16001420001	ND
2016-03-23	E16003505001	ND
2017-06-09	E17004877001	ND