trans-1,2-Dichloroethylene
Northwest Harris County MUD 5
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 |
|---|---|---|---|---|
| 2014 | ND | 1 | 0 | ND |
| 2015 | ND | 3 | 0 | ND |
| 2016 | ND | 3 | 0 | ND |
| 2017 | ND | 4 | 0 | ND |
| 2018 | ND | 4 | 0 | ND |
| 2019 | ND | 4 | 0 | ND |
ppb = parts per billion
State and national drinking water standards and health guidelines
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 |
|---|---|---|
| 2014-10-14 | AC69599 | ND |
| 2015-07-28 | AD01247 | ND |
| 2015-07-28 | AD01279 | ND |
| 2015-07-28 | AD01287 | ND |
| 2016-11-09 | AD57442 | ND |
| 2016-11-09 | AD57450 | ND |
| 2016-11-09 | AD57448 | ND |
| 2017-08-08 | AD92417 | ND |
| 2017-09-26 | AD98059 | ND |
| 2017-09-26 | AD98065 | ND |
| 2017-09-26 | AD98063 | ND |
| 2018-02-07 | AE12763 | ND |
| 2018-05-10 | AE25945 | ND |
| 2018-05-10 | AE25951 | ND |
| 2018-05-10 | AE25947 | ND |
| 2019-02-05 | AE52907 | ND |
| 2019-03-26 | AE59980 | ND |
| 2019-03-26 | AE59970 | ND |
| 2019-03-26 | AE59964 | ND |