2,4,5-TP (Silvex)
Oakdale
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 | N/A | 0 | 0 | N/A |
| 2021 | ND | 3 | 0 | ND |
| 2022 | ND | 5 | 0 | ND |
| 2023 | ND | 3 | 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 |
|---|---|---|
| 2018-08-29 | 18H2504-04 | ND |
| 2018-08-29 | 18H2501-01 | ND |
| 2018-11-28 | 18K1049-01 | ND |
| 2018-11-28 | 18K1049-02 | ND |
| 2019-09-24 | 19I1346-03 | ND |
| 2019-10-21 | 19J1159-01 | ND |
| 2021-11-30 | 21K1445-03 | ND |
| 2021-11-30 | 21K1445-02 | ND |
| 2021-11-30 | 21K1445-01 | ND |
| 2022-03-30 | 22C1204-01 | ND |
| 2022-03-30 | 22C1204-02 | ND |
| 2022-05-17 | 22E1283-01 | ND |
| 2022-09-14 | 22I0893-02 | ND |
| 2022-12-29 | 22L1157-01 | ND |
| 2023-06-06 | 23F0363-01 | ND |
| 2023-08-22 | 23H2240-01 | ND |
| 2023-12-28 | 23L0918-02 | ND |