2,4,5-TP (Silvex)
City of Moses Lake
2(2,4,5-trichlorophenoxy) propionic acid (2,4,5-TP or Silvex) is a cancer-causing herbicide banned in the U.S. in 1985 because of its toxicity. It is still detected as a groundwater contaminant in areas where it was sprayed or stored.
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 | 9 | 0 | ND |
| 2019 | ND | 4 | 0 | ND |
| 2020 | N/A | 0 | 0 | N/A |
| 2021 | ND | 4 | 0 | ND |
| 2022 | ND | 1 | 0 | ND |
| 2023 | N/A | 0 | 0 | N/A |
ppb = parts per billion
State, National, and Health Guidelines for Drinking Water
EWG Health Guideline: 3 ppb
The EWG Health Guideline of 3 ppb for 2,4,5-TP 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): 50 ppb
ppb = parts per billion
All test results
| Date | Lab ID | Result |
|---|---|---|
| 2018-04-03 | ND | |
| 2018-04-03 | ND | |
| 2018-04-03 | ND | |
| 2018-04-03 | ND | |
| 2018-07-09 | ND | |
| 2018-08-13 | ND | |
| 2018-09-18 | ND | |
| 2018-12-10 | ND | |
| 2018-12-17 | ND | |
| 2019-03-26 | ND | |
| 2019-03-26 | ND | |
| 2019-04-01 | ND | |
| 2019-04-01 | ND | |
| 2021-06-14 | 4130307 | ND |
| 2021-06-16 | 4144642 | ND |
| 2021-06-16 | 4144643 | ND |
| 2021-07-21 | 4149237 | ND |
| 2022-06-13 | 4299742 | ND |