trans-1,2-Dichloroethylene
Harris County Municipal Utility District 189
1,2-Dichloroethylene, a neurotoxic solvent, exists in two different forms: trans-1,2-dichloroethylene and cis-1,2-dichloroethylene. A mixture of the two forms is used to manufacture other solvents and chemical products.
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 | 2 | 0 | ND |
| 2021 | ND | 1 | 0 | ND |
| 2022 | ND | 1 | 0 | ND |
| 2023 | ND | 3 | 0 | ND |
ppb = parts per billion
State, National, and Health Guidelines for Drinking Water
EWG Health Guideline: 60 ppb
The EWG Health Guideline of 60 ppb for trans-1,2-dichloroethylene 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 harm to internal organs.
EPA Maximum Contaminant
Level (MCL): 100 ppb
The legal limit for trans-1,2-dichloroethylene, established in 1991, was based on a toxicity study in laboratory animals conducted in the 1980s.
ppb = parts per billion
All test results
| Date | Lab ID | Result |
|---|---|---|
| 2018-05-17 | AE26817 | ND |
| 2018-05-17 | AE26821 | ND |
| 2019-07-08 | AE73468 | ND |
| 2019-07-08 | AE73470 | ND |
| 2020-06-23 | AF16542 | ND |
| 2020-06-23 | AF16548 | ND |
| 2021-10-14 | AF73563 | ND |
| 2022-04-05 | AF92017 | ND |
| 2023-07-20 | AG49613 | ND |
| 2023-10-12 | AG59736 | ND |
| 2023-11-02 | AG62177 | ND |