Dibromochloromethane
Coulterville
Dibromochloromethane, one of the total trihalomethanes (TTHMs), is formed when chlorine or other disinfectants are used to treat drinking water. Dibromochloromethane and other disinfection byproducts increase the risk of cancer and may cause problems during pregnancy. Click here to read more about disinfection byproducts.
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 | 0.325 ppb | 4 | 2 | ND - 0.686 ppb |
| 2019 | 0.940 ppb | 4 | 3 | ND - 2.07 ppb |
| 2020 | 0.810 ppb | 4 | 4 | 0.650 ppb - 1.11 ppb |
| 2021 | 0.551 ppb | 4 | 3 | ND - 0.941 ppb |
| 2022 | 0.979 ppb | 4 | 4 | 0.572 ppb - 1.76 ppb |
| 2023 | 0.695 ppb | 4 | 3 | ND - 1.03 ppb |
ppb = parts per billion
State, National, and Health Guidelines for Drinking Water
EWG Health Guideline: 0.1 ppb
The EWG Health Guideline of 0.1 ppb for dibromochloromethane was based on the California Office of Environmental Health Hazard Assessment's public health goal, the level of a drinking water contaminant that does not pose a significant health risk. This health guideline protects against cancer and harm to fetal growth and development.
ppb = parts per billion
All test results
| Date | Lab ID | Result |
|---|---|---|
| 2018-02-13 | 8022181-02 | ND |
| 2018-05-15 | 8053308-02 | 0.613 ppb |
| 2018-08-20 | 8084327-02 | 0.686 ppb |
| 2018-11-04 | 8110985-02 | ND |
| 2019-02-03 | 9020409-02 | ND |
| 2019-05-05 | 9051338-02 | 0.661 ppb |
| 2019-08-04 | 9080780-02 | 2.07 ppb |
| 2019-11-17 | 9113135-02 | 1.03 ppb |
| 2020-02-02 | 0020627-02 | 0.650 ppb |
| 2020-05-03 | 0050537-02 | 1.11 ppb |
| 2020-08-09 | 0082272-02 | 0.719 ppb |
| 2020-11-22 | 0114365-02 | 0.761 ppb |
| 2021-02-07 | EB01721-02 | ND |
| 2021-05-02 | EE00500-02 | 0.636 ppb |
| 2021-08-16 | EH04018-02 | 0.941 ppb |
| 2021-11-07 | EK01880-02 | 0.628 ppb |
| 2022-02-15 | FB03272-02 | 0.572 ppb |
| 2022-05-08 | FE01935-02 | 1.01 ppb |
| 2022-08-08 | FH02266-02 | 1.76 ppb |
| 2022-11-20 | FK04195-02 | 0.573 ppb |
| 2023-02-12 | GB02608-02 | 1.03 ppb |
| 2023-05-15 | GE03475-02 | 0.954 ppb |
| 2023-08-13 | GH03092-02 | 0.797 ppb |
| 2023-11-05 | GK01056-02 | ND |