2,4,5-TP (Silvex)
Bear Valley 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 | ND | 4 | 0 | ND |
| 2019 | ND | 2 | 0 | ND |
| 2020 | ND | 5 | 0 | ND |
| 2021 | N/A | 0 | 0 | N/A |
| 2022 | N/A | 0 | 0 | N/A |
| 2023 | ND | 4 | 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 |
|---|---|---|
| 2018-04-24 | 8045215-01 | ND |
| 2018-05-29 | 8055386-01 | ND |
| 2018-07-17 | 8074944-01 | ND |
| 2018-11-27 | 8114887-01 | ND |
| 2019-02-19 | 9024042-01 | ND |
| 2019-11-13 | 9036887-01 | ND |
| 2020-01-29 | 21798040.00 | ND |
| 2020-04-15 | 22362555.00 | ND |
| 2020-04-29 | 22362576.00 | ND |
| 2020-07-29 | 22949612.00 | ND |
| 2020-08-19 | 23136912.00 | ND |
| 2023-05-15 | 29053720.00 | ND |
| 2023-05-15 | 29053735.00 | ND |
| 2023-07-18 | 29651638.00 | ND |
| 2023-07-18 | 29651673.00 | ND |