2,4,5-TP (Silvex)
Yosemite Spring Park Utility Company
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.
Testing results - average by year
Year | Average result | Samples taken | Detections | Range of results |
---|---|---|---|---|
2014 | N/A | 0 | 0 | N/A |
2015 | N/A | 0 | 0 | N/A |
2016 | ND | 2 | 0 | ND |
2017 | ND | 8 | 0 | ND |
2018 | ND | 3 | 0 | ND |
2019 | ND | 1 | 0 | ND |
ppb = parts per billion
State and national drinking water standards and health guidelines
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 |
---|---|---|
2016-11-23 | 5802-002-1305 | ND |
2016-11-23 | 5802-003-1350 | ND |
2017-12-06 | 5802-017-0835 | ND |
2017-12-06 | 5802-021-1435 | ND |
2017-12-06 | 5802-023-1150 | ND |
2017-12-06 | 5802-025-1045 | ND |
2017-12-13 | 5802-013-1430 | ND |
2017-12-13 | 5802-020-1235 | ND |
2017-12-13 | 5802-027-1310 | ND |
2017-12-13 | 5802-043-1100 | ND |
2018-01-10 | 5802-016-1400 | ND |
2018-12-19 | 5802-026-1350 | ND |
2018-12-26 | 5802-018-1325 | ND |
2019-12-20 | 5802-002-1106 | ND |