1,1,1,2-Tetrachloroethane
Helena Water System
1,1,1,2-Tetrachloroethane is a synthetic chemical used in metal degreasing and as an intermediate in industrial chemical production.
14
Samples
0
Samples exceeding legal limit (MCL)
0
Samples exceeding
health guidelines
Testing results - average by year
| Year | Average result | Samples taken | Detections | Range of results |
|---|---|---|---|---|
| 2013 | N/A | 0 | 0 | N/A |
| 2014 | ND | 2 | 0 | ND |
| 2015 | ND | 3 | 0 | ND |
| 2016 | ND | 2 | 0 | ND |
| 2017 | ND | 2 | 0 | ND |
| 2018 | ND | 3 | 0 | ND |
| 2019 | ND | 2 | 0 | ND |
ppb = parts per billion
State and national drinking water standards and health guidelines
EWG Health Guideline 1 ppb
The EWG Health Guideline of 1 ppb for 1,1,1,2-tetrachloroethane was defined by the Environmental Protection Agency as a one-in-a-million lifetime risk of cancer. Values greater than one-in-a-million cancer risk level can result in increased cancer cases above one in a million people.
ppb = parts per billion
All test results
| Date | Lab ID | Result |
|---|---|---|
| 2014-05-27 | H14050436-001A | ND |
| 2014-05-27 | H14050436-002A | ND |
| 2015-05-21 | H15050321-001A | ND |
| 2015-05-21 | H15050321-002A | ND |
| 2015-05-21 | H15050321-003A | ND |
| 2016-05-10 | H16050166-001A | ND |
| 2016-05-10 | H16050166-002A | ND |
| 2017-05-25 | H17050520-001A | ND |
| 2017-05-25 | H17050520-002A | ND |
| 2018-05-29 | H18050689-001A | ND |
| 2018-05-29 | H18050689-002A | ND |
| 2018-05-30 | H18050718-001A | ND |
| 2019-07-12 | H19070266-001A | ND |
| 2019-07-12 | H19070266-002A | ND |