2,4,5-TP (Silvex)
Rockwood People's Utilities Department
NOTE: Rockwood People's Utilities Department purchases water from Portland Water Bureau which is required to test for 2,4,5-tp (silvex). Sample information shown below was taken by Portland Water Bureau.
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 | 1 | 0 | ND |
| 2019 | ND | 2 | 0 | ND |
| 2020 | ND | 3 | 0 | ND |
| 2021 | ND | 1 | 0 | ND |
| 2022 | ND | 2 | 0 | ND |
| 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
NOTE: Rockwood People's Utilities Department purchases water from Portland Water Bureau which is required to test for 2,4,5-tp (silvex). Sample information shown below was taken by Portland Water Bureau.
| Date | Lab ID | Result |
|---|---|---|
| 2018-03-15 | BC03118-S | ND |
| 2020-05-12 | BC38533-S | ND |
| 2020-08-04 | 202008070432-S | ND |
| 2020-08-05 | 202008070418-S | ND |
| 2021-08-04 | BC60213-S | ND |
| 2023-04-04 | 380-42758-1-S | ND |
| 2023-08-15 | 380-59561-1-S | ND |
| 2023-08-29 | 380-61323-1 | ND |
| 2023-10-02 | 380-65583-1-S | ND |