Styrene
CTWC - Shoreline Region-Guilford System
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.
Samples
Samples exceeding legal limit (MCL)
Samples exceeding
health guidelines
Testing results - average by year
| Year | Average result | Samples taken | Detections | Range of results |
|---|---|---|---|---|
| 2018 | ND | 11 | 0 | ND |
| 2019 | ND | 10 | 0 | ND |
| 2020 | ND | 12 | 0 | ND |
| 2021 | ND | 11 | 0 | ND |
| 2022 | ND | 14 | 0 | ND |
| 2023 | ND | 10 | 0 | ND |
ppb = parts per billion
State, National, and Health Guidelines for Drinking Water
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 |
|---|---|---|
| 2018-01-16 | BZ73485VOC1 | ND |
| 2018-03-30 | CA11464VOC1 | ND |
| 2018-04-11 | CA18261VOC1 | ND |
| 2018-07-09 | CA85598VOC1 | ND |
| 2018-07-17 | CA91979 | ND |
| 2018-09-13 | VOC1 200505275 | ND |
| 2018-09-13 | VOC1 200505276 | ND |
| 2018-09-13 | VOC1 200505266 | ND |
| 2018-09-19 | VOC1 200506116 | ND |
| 2018-09-20 | VOC1 200506324 | ND |
| 2018-10-25 | VOC1 200510568 | ND |
| 2019-01-30 | VOC1 200520057 | ND |
| 2019-06-24 | VOC1 200538005 | ND |
| 2019-07-08 | VOC1 200541172 | ND |
| 2019-07-08 | VOC1 200539194 | ND |
| 2019-07-16 | VOC1 200541091 | ND |
| 2019-07-16 | VOC1 200540648 | ND |
| 2019-07-16 | VOC1 200540644 | ND |
| 2019-09-17 | VOC1 200549238 | ND |
| 2019-09-18 | VOC1 200549465 | ND |
| 2019-12-10 | VOC1 200559663 | ND |
| 2020-01-14 | VOC1 200562856 | ND |
| 2020-01-20 | VOC1 200563521 | ND |
| 2020-01-21 | VOC1 200563515 | ND |
| 2020-01-30 | VOC1 200564603 | ND |
| 2020-02-11 | VOC1 200565799 | ND |
| 2020-02-25 | VOC1 200567276 | ND |
| 2020-04-01 | VOC1 200571017 | ND |
| 2020-06-16 | VOC1 200579533 | ND |
| 2020-07-14 | VOC1 200582708 | ND |
| 2020-07-14 | VOC1 200582710 | ND |
| 2020-10-06 | VOC1 200592866 | ND |
| 2020-10-13 | VOC1 200593765 | ND |
| 2021-01-05 | VOC1 200602753 | ND |
| 2021-01-06 | VOC1 200602996 | ND |
| 2021-01-25 | VOC1 200604768 | ND |
| 2021-06-07 | VOC1 200621229 | ND |
| 2021-06-23 | VOC1 200622004 | ND |
| 2021-06-29 | VOC1 200622710 | ND |
| 2021-07-12 | VOC1 200624252 | ND |
| 2021-07-12 | VOC1 200624251 | ND |
| 2021-07-20 | VOC1 200625447 | ND |
| 2021-10-11 | V300077965 300077966 | ND |
| 2021-12-06 | V300113153 300113155 | ND |
| 2022-01-11 | CK14095 | ND |
| 2022-01-11 | CK14105 | ND |
| 2022-02-28 | CK76192 | ND |
| 2022-03-07 | CK80900 | ND |
| 2022-04-18 | CL11174 | ND |
| 2022-06-14 | CL56476 | ND |
| 2022-06-22 | CL62299 | ND |
| 2022-07-06 | CL71457 | ND |
| 2022-07-06 | CL71463 | ND |
| 2022-07-26 | CL89875 | ND |
| 2022-08-02 | CL95977 | ND |
| 2022-08-15 | CM05635 | ND |
| 2022-08-29 | CM17830 | ND |
| 2022-12-19 | CN08248 | ND |
| 2023-01-03 | CN16052 | ND |
| 2023-01-09 | CN19603 | ND |
| 2023-01-10 | CN20796 | ND |
| 2023-01-10 | CN20798 | ND |
| 2023-02-13 | CN41858 | ND |
| 2023-05-10 | CO03368 | ND |
| 2023-06-13 | CO27277 | ND |
| 2023-09-18 | CP02429 | ND |
| 2023-11-28 | CP55322 | ND |
| 2023-11-29 | CP56431 | ND |