2,4,5-TP (Silvex)
Paw Penn District
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 | ND | 2 | 0 | ND |
| 2020 | ND | 15 | 0 | ND |
| 2021 | N/A | 0 | 0 | N/A |
| 2022 | N/A | 0 | 0 | N/A |
| 2023 | ND | 14 | 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 |
|---|---|---|
| 2019-07-15 | 45716201 | ND |
| 2019-10-31 | 43999701 | ND |
| 2020-04-06 | 22069253.00 | ND |
| 2020-04-06 | 22069224.00 | ND |
| 2020-04-08 | 22069384.00 | ND |
| 2020-04-08 | 22069442.00 | ND |
| 2020-04-14 | 22069355.00 | ND |
| 2020-04-16 | 22069471.00 | ND |
| 2020-04-16 | 22069413.00 | ND |
| 2020-05-06 | 22261481.00 | ND |
| 2020-07-01 | 22652305.00 | ND |
| 2020-07-01 | 22652276.00 | ND |
| 2020-07-01 | 22652392.00 | ND |
| 2020-07-09 | 22652218.00 | ND |
| 2020-07-09 | 22652247.00 | ND |
| 2020-07-09 | 22652334.00 | ND |
| 2020-07-13 | 22652363.00 | ND |
| 2023-04-06 | 28749312.00 | ND |
| 2023-04-06 | 28749454.00 | ND |
| 2023-04-06 | 28749443.00 | ND |
| 2023-04-13 | 28749399.00 | ND |
| 2023-04-13 | 28749370.00 | ND |
| 2023-04-13 | 28749341.00 | ND |
| 2023-06-07 | 29155720.00 | ND |
| 2023-07-13 | 29346819.00 | ND |
| 2023-07-13 | 29346871.00 | ND |
| 2023-07-13 | 29346790.00 | ND |
| 2023-07-13 | 29346881.00 | ND |
| 2023-07-20 | 29346761.00 | ND |
| 2023-07-20 | 29346732.00 | ND |
| 2023-07-20 | 29346703.00 | ND |