2,4,5-TP (Silvex)
City of Shavano Park
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 | ND | 6 | 0 | ND |
| 2021 | ND | 1 | 0 | ND |
| 2022 | ND | 1 | 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
| Date | Lab ID | Result |
|---|---|---|
| 2020-02-24 | AE99578 | ND |
| 2020-02-24 | AE99582 | ND |
| 2020-02-24 | AE99584 | ND |
| 2020-05-15 | AF11926 | ND |
| 2020-05-15 | AF11930 | ND |
| 2020-07-13 | AF19185 | ND |
| 2021-06-18 | AF58934 | ND |
| 2022-03-09 | AF88473 | ND |
| 2023-03-16 | AG33402 | ND |
| 2023-06-22 | AG45678 | ND |
| 2023-06-22 | AG45679 | ND |
| 2023-06-22 | AG45681 | ND |