2,4,5-TP (Silvex)
Redmond Water Department
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 | N/A | 0 | 0 | N/A |
| 2021 | ND | 15 | 0 | ND |
| 2022 | ND | 1 | 0 | ND |
| 2023 | ND | 16 | 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 |
|---|---|---|
| 2021-05-11 | 2132264-S | ND |
| 2021-05-11 | 2132295-S | ND |
| 2021-05-18 | 2133715-S | ND |
| 2021-05-18 | 2133712-S | ND |
| 2021-05-18 | 2133726-S | ND |
| 2021-06-02 | 2137359-S | ND |
| 2021-06-02 | 2137357-S | ND |
| 2021-06-09 | 2132299-S | ND |
| 2021-08-25 | 2161788-S | ND |
| 2021-08-25 | 2161793-S | ND |
| 2021-08-25 | 2161794-S | ND |
| 2021-08-25 | 2161792-S | ND |
| 2021-08-25 | 2161791-S | ND |
| 2021-08-25 | 2161787-S | ND |
| 2021-08-25 | 2161795-S | ND |
| 2022-08-10 | 22-51468-S | ND |
| 2023-07-13 | 23-40887-S | ND |
| 2023-07-13 | 23-40884-S | ND |
| 2023-07-13 | 23-40882-S | ND |
| 2023-07-13 | 23-40863-S | ND |
| 2023-07-13 | 23-40886-S | ND |
| 2023-07-13 | 23-40885-S | ND |
| 2023-07-13 | 23-40883-S | ND |
| 2023-07-17 | 23-41527-S | ND |
| 2023-10-23 | 23-64753-S | ND |
| 2023-10-23 | 23-64752-S | ND |
| 2023-10-23 | 23-64748-S | ND |
| 2023-10-23 | 23-64754-S | ND |
| 2023-10-23 | 23-64744-S | ND |
| 2023-10-23 | 23-64750-S | ND |
| 2023-10-23 | 23-64743-S | ND |
| 2023-10-23 | 23-64746-S | ND |