1,2,4-Trichlorobenzene
City of San Marcos
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 |
|---|---|---|---|---|
| 2014 | ND | 5 | 0 | ND |
| 2015 | ND | 6 | 0 | ND |
| 2016 | ND | 6 | 0 | ND |
| 2017 | ND | 7 | 0 | ND |
| 2018 | ND | 6 | 0 | ND |
| 2019 | ND | 6 | 0 | ND |
ppb = parts per billion
State and national drinking water standards and health guidelines
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 |
|---|---|---|
| 2014-03-12 | AC63077 | ND |
| 2014-08-12 | AC63071 | ND |
| 2014-08-12 | AC63073 | ND |
| 2014-08-12 | AC63087 | ND |
| 2014-08-12 | AC63075 | ND |
| 2015-06-10 | AC95472 | ND |
| 2015-06-10 | AC95470 | ND |
| 2015-06-10 | AC95474 | ND |
| 2015-06-10 | AC95468 | ND |
| 2015-09-23 | AD08299 | ND |
| 2015-09-23 | AD08303 | ND |
| 2016-03-16 | AD29111 | ND |
| 2016-09-16 | AD49839 | ND |
| 2016-11-28 | AD59222 | ND |
| 2016-11-28 | AD59220 | ND |
| 2016-12-12 | AD61688 | ND |
| 2016-12-12 | AD61664 | ND |
| 2017-02-22 | AD71534 | ND |
| 2017-05-03 | AD82464 | ND |
| 2017-05-03 | AD82462 | ND |
| 2017-05-03 | AD82466 | ND |
| 2017-05-03 | AD82468 | ND |
| 2017-07-12 | AD89095 | ND |
| 2017-10-12 | AE00574 | ND |
| 2018-01-25 | AE10638 | ND |
| 2018-01-25 | AE10564 | ND |
| 2018-01-25 | AE10572 | ND |
| 2018-01-25 | AE10574 | ND |
| 2018-04-11 | AE22067 | ND |
| 2018-07-26 | AE34698 | ND |
| 2019-01-16 | AE50162 | ND |
| 2019-01-16 | AE50166 | ND |
| 2019-01-16 | AE50168 | ND |
| 2019-01-16 | AE50164 | ND |
| 2019-04-16 | AE62552 | ND |
| 2019-07-09 | AE73687 | ND |