Chloromethane
North Peninsula
Chloromethane is an industrial solvent, aerosol propellant and a refrigerant. It also forms as a byproduct of water disinfection. The EPA classifies chloromethane as possibly carcinogenic to humans.
18
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 |
|---|---|---|---|---|
| 2013 | ND | 1 | 0 | ND |
| 2014 | ND | 4 | 0 | ND |
| 2015 | ND | 3 | 0 | ND |
| 2016 | N/A | 0 | 0 | N/A |
| 2017 | N/A | 0 | 0 | N/A |
| 2018 | 0.433 ppb | 3 | 1 | ND - 1.30 ppb |
| 2019 | ND | 1 | 0 | ND |
| 2020 | N/A | 0 | 0 | N/A |
| 2021 | 0.600 ppb | 2 | 1 | ND - 1.20 ppb |
| 2022 | ND | 2 | 0 | ND |
| 2023 | 0.550 ppb | 2 | 1 | ND - 1.10 ppb |
ppb = parts per billion
State, National, and Health Guidelines for Drinking Water
EWG Health Guideline: 2.69 ppb
The EWG Health Guideline of 2.69 ppb for chloromethane was defined by the Environmental Protection Agency as a benchmark for testing under the Unregulated Contaminant Monitoring Rule program. This health guideline protects against cancer.
ppb = parts per billion
All test results
| Date | Lab ID | Result |
|---|---|---|
| 2013-09-09 | 201304728 | ND |
| 2014-03-25 | 201401150 | ND |
| 2014-03-25 | 201401152 | ND |
| 2014-03-25 | 201401148 | ND |
| 2014-03-25 | 201401154 | ND |
| 2015-09-29 | 201506099 | ND |
| 2015-09-29 | 201506100 | ND |
| 2015-09-29 | 201506098 | ND |
| 2018-05-15 | 1.30 ppb | |
| 2018-05-21 | ND | |
| 2018-10-26 | ND | |
| 2019-06-11 | ND | |
| 2021-06-22 | 4142805 | 1.20 ppb |
| 2021-08-23 | 4169117 | ND |
| 2022-11-14 | 4382867 | ND |
| 2022-11-15 | 4382872 | ND |
| 2023-08-28 | 4514708 | 1.10 ppb |
| 2023-08-28 | 4514710 | ND |