Styrene

City of Mountain Home

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	2	ND
2015	ND	3	ND
2016	ND	2	ND
2017	ND	1	ND
2018	N/A	0	N/A
2019	ND	2	ND

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
2014-07-01	V1424601	ND
2014-07-01	V1424597	ND
2015-03-11	V1509330	ND
2015-04-08	V1513098	ND
2015-12-17	V1554310	ND
2016-08-23	V1638144	ND
2016-08-23	V1638147	ND
2017-12-20	V1759182	ND
2019-06-11	V1927644	ND
2019-06-11	V1927642	ND