trans-1,2-Dichloroethylene
Nocona Hills Water Supply Corporation
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 | 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: 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 |
|---|---|---|
| 2018-12-10 | Q1850817001 | ND |
| 2018-12-10 | Q1850817004 | ND |
| 2019-02-20 | Q1907488002 | ND |
| 2019-02-20 | Q1907488007 | ND |
| 2020-09-21 | Q2037478001 | ND |
| 2020-09-21 | Q2037478003 | ND |
| 2021-06-21 | Q2116016005 | ND |
| 2021-06-21 | Q2116016007 | ND |
| 2022-05-10 | Q2213917001 | ND |
| 2022-05-10 | Q2213917003 | ND |
| 2023-07-05 | Q2326100006 | ND |
| 2023-07-05 | Q2326100008 | ND |
| 2023-10-03 | Q2342315001 | ND |