trans-1,2-Dichloroethylene
Guilford Water Authority
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 | 3 | 0 | ND |
| 2019 | ND | 1 | 0 | ND |
| 2020 | ND | 3 | 0 | ND |
| 2021 | ND | 5 | 0 | ND |
| 2022 | ND | 1 | 0 | ND |
| 2023 | ND | 7 | 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 |
|---|---|---|
| 2018-05-29 | (104) | ND |
| 2018-09-04 | (104) | ND |
| 2018-12-11 | (104) | ND |
| 2019-03-05 | (104) | ND |
| 2020-11-02 | 23491227.00 | ND |
| 2020-11-02 | 23491206.00 | ND |
| 2020-11-02 | 23491185.00 | ND |
| 2021-03-09 | 24197198.00 | ND |
| 2021-03-09 | 24197219.00 | ND |
| 2021-03-29 | 24197241.00 | ND |
| 2021-03-29 | 24197262.00 | ND |
| 2021-11-04 | 25719755.00 | ND |
| 2022-04-25 | 26601196.00 | ND |
| 2023-05-17 | 29053146.00 | ND |
| 2023-05-17 | 29053167.00 | ND |
| 2023-05-24 | 29053217.00 | ND |
| 2023-05-24 | 29053196.00 | ND |
| 2023-08-01 | 29447932.00 | ND |
| 2023-08-01 | 29447952.00 | ND |
| 2023-08-01 | 29447912.00 | ND |