2,4,5-TP (Silvex)
City of Sonoma
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.
13
Samples
0
Samples exceeding legal limit (MCL)
0
Samples exceeding
health guidelines
Testing results - average by year
| Year | Average result | Samples taken | Detections | Range of results |
|---|---|---|---|---|
| 2013 | N/A | 0 | 0 | N/A |
| 2014 | ND | 5 | 0 | ND |
| 2015 | ND | 1 | 0 | ND |
| 2016 | ND | 1 | 0 | ND |
| 2017 | ND | 4 | 0 | ND |
| 2018 | ND | 1 | 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 |
|---|---|---|
| 2014-03-17 | 9590-001-1050 | ND |
| 2014-03-17 | 9590-003-0920 | ND |
| 2014-03-17 | 9590-004-0950 | ND |
| 2014-03-17 | 9590-006-0830 | ND |
| 2014-09-03 | 9590-023-0910 | ND |
| 2015-05-13 | 9590-023-0920 | ND |
| 2016-03-29 | 9590-002-0735 | ND |
| 2017-04-04 | 9590-001-0900 | ND |
| 2017-04-04 | 9590-003-1000 | ND |
| 2017-04-04 | 9590-004-1125 | ND |
| 2017-04-04 | 9590-006-1040 | ND |
| 2018-10-23 | 9590-023-0945 | ND |
| 2019-09-04 | 9590-002-1208 | ND |