1,2,4-Trichlorobenzene
El Oso Water Supply Corporation
1,2,4-Trichlorobenzene is an industrial solvent that can harm the adrenal glands and may increase the risk of cancer.
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 | 2 | 0 | ND |
| 2019 | ND | 2 | 0 | ND |
| 2020 | ND | 4 | 0 | ND |
| 2021 | ND | 2 | 0 | ND |
| 2022 | ND | 2 | 0 | ND |
| 2023 | ND | 3 | 0 | ND |
ppb = parts per billion
State, National, and Health Guidelines for Drinking Water
EWG Health Guideline: 5 ppb
The EWG Health Guideline of 5 ppb for 1,2,4-trichlorobenzene 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 hormone disruption.
EPA Maximum Contaminant
Level (MCL): 70 ppb
The legal limit for 1,2,4-trichlorobenzene, established in 1992, was based on a toxicity study in laboratory animals conducted in 1981. This limit may not fully protect against hormone disruption.
ppb = parts per billion
All test results
| Date | Lab ID | Result |
|---|---|---|
| 2018-01-24 | AE10200 | ND |
| 2018-01-24 | AE10234 | ND |
| 2019-02-19 | AE54844 | ND |
| 2019-02-19 | AE54850 | ND |
| 2020-06-09 | AF14659 | ND |
| 2020-06-09 | AF14661 | ND |
| 2020-09-11 | AF27359 | ND |
| 2020-11-13 | AF34597 | ND |
| 2021-01-26 | AF41115 | ND |
| 2021-01-26 | AF41117 | ND |
| 2022-03-10 | AF88679 | ND |
| 2022-03-10 | AF88683 | ND |
| 2023-02-16 | AG29365 | ND |
| 2023-02-16 | AG29367 | ND |
| 2023-03-29 | AG34750 | ND |