trans-1,2-Dichloroethylene
Merrimack Village District
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 | 4 | 0 | ND |
| 2015 | ND | 4 | 0 | ND |
| 2016 | ND | 2 | 0 | ND |
| 2017 | ND | 2 | 0 | ND |
| 2018 | ND | 3 | 0 | ND |
| 2019 | ND | 3 | 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 |
|---|---|---|
| 2014-04-07 | 14040103-002 | ND |
| 2014-04-07 | 14040103-003 | ND |
| 2014-04-07 | 14040103-004 | ND |
| 2014-04-07 | 14040103-001 | ND |
| 2015-04-07 | 15040059-001 | ND |
| 2015-04-07 | 15040059-002 | ND |
| 2015-04-14 | 15040142-001 | ND |
| 2015-04-14 | 15040142-002 | ND |
| 2016-04-21 | 16040293-001 | ND |
| 2016-04-21 | 16040292-001 | ND |
| 2017-05-09 | 17050144-001 | ND |
| 2017-05-09 | 17050143-001 | ND |
| 2018-04-05 | 18040073-001 | ND |
| 2018-04-05 | 18040074-001 | ND |
| 2018-04-05 | 18040075-001 | ND |
| 2019-06-14 | 19060223-001 | ND |
| 2019-06-14 | 19060224-001 | ND |
| 2019-06-14 | 19060225-001 | ND |