2,4,5-TP (Silvex)
San Francisco City Water System
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.
16
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 | N/A | 0 | 0 | N/A |
| 2015 | N/A | 0 | 0 | N/A |
| 2016 | N/A | 0 | 0 | N/A |
| 2017 | N/A | 0 | 0 | N/A |
| 2018 | ND | 16 | 0 | ND |
| 2019 | N/A | 0 | 0 | N/A |
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 |
|---|---|---|
| 2018-01-11 | 9590-007-1115 | ND |
| 2018-03-06 | 9590-004-1031 | ND |
| 2018-03-06 | 9590-008-0914 | ND |
| 2018-03-08 | 9590-006-0925 | ND |
| 2018-04-17 | 9590-007-1055 | ND |
| 2018-06-12 | 9590-004-1058 | ND |
| 2018-06-12 | 9590-006-1012 | ND |
| 2018-06-12 | 9590-008-0930 | ND |
| 2018-07-17 | 9590-007-0519 | ND |
| 2018-09-18 | 9590-004-0855 | ND |
| 2018-09-18 | 9590-006-0945 | ND |
| 2018-09-18 | 9590-008-1025 | ND |
| 2018-10-17 | 9590-007-0730 | ND |
| 2018-12-11 | 9590-004-0845 | ND |
| 2018-12-11 | 9590-006-0915 | ND |
| 2018-12-11 | 9590-008-1045 | ND |