2,4,5-TP (Silvex)
Ephrata Area Joint Authority
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 | N/A | 0 | 0 | N/A |
| 2019 | N/A | 0 | 0 | N/A |
| 2020 | ND | 8 | 0 | ND |
| 2021 | N/A | 0 | 0 | N/A |
| 2022 | ND | 1 | 0 | ND |
| 2023 | ND | 8 | 0 | ND |
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 |
|---|---|---|
| 2020-04-06 | 22168927.00 | ND |
| 2020-04-13 | 22169110.00 | ND |
| 2020-04-13 | 22169109.00 | ND |
| 2020-04-16 | 22365709.00 | ND |
| 2020-07-13 | 22754040.00 | ND |
| 2020-07-13 | 22754039.00 | ND |
| 2020-07-14 | 22754084.00 | ND |
| 2020-07-17 | 22952585.00 | ND |
| 2022-04-12 | 26604804.00 | ND |
| 2023-04-14 | 29056973.00 | ND |
| 2023-04-14 | 29056974.00 | ND |
| 2023-04-14 | 29057139.00 | ND |
| 2023-04-14 | 29056972.00 | ND |
| 2023-07-11 | 29654739.00 | ND |
| 2023-07-18 | 29654906.00 | ND |
| 2023-08-09 | 29844099.00 | ND |
| 2023-08-29 | 29844138.00 | ND |