MTBE
Theresa Waterworks
MTBE was used as gasoline oxygenation additive to boost the octane number. In 2005, MTBE was replaced by ethanol as a gasoline additive. MTBE causes cancers in rats.
8
Samples
0
Samples exceeding legal limit (MCL)
0
Samples exceeding
health guidelines
Testing results - average by year
| Year | Average result | Samples taken | Detections | Range of results |
|---|---|---|---|---|
| 2018 | 2.40 ppb | 1 | 1 | 2.40 ppb |
| 2019 | 2.60 ppb | 3 | 3 | 2.10 ppb - 3.30 ppb |
| 2020 | 2.95 ppb | 2 | 2 | 2.70 ppb - 3.20 ppb |
| 2021 | 3.60 ppb | 2 | 2 | 3.00 ppb - 4.20 ppb |
| 2022 | N/A | 0 | 0 | N/A |
| 2023 | N/A | 0 | 0 | N/A |
ppb = parts per billion
State, National, and Health Guidelines for Drinking Water
EWG Health Guideline: 13 ppb
The EWG Health Guideline of 13 ppb for MTBE 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.
ppb = parts per billion
All test results
| Date | Lab ID | Result |
|---|---|---|
| 2018-09-12 | 1080103 | 2.40 ppb |
| 2019-07-02 | 1132020 | 2.10 ppb |
| 2019-07-02 | 1132019 | 2.40 ppb |
| 2019-07-16 | 1134783 | 3.30 ppb |
| 2020-08-12 | 1206606 | 2.70 ppb |
| 2020-08-12 | 1206554 | 3.20 ppb |
| 2021-04-12 | 1248254 | 4.20 ppb |
| 2021-07-20 | 1266314 | 3.00 ppb |