Diquat
City of Morgan Hill
Diquat is a herbicide used on potato crops and aquatic weeds.
42
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 | 8 | 0 | ND |
| 2015 | ND | 2 | 0 | ND |
| 2016 | ND | 12 | 0 | ND |
| 2017 | ND | 6 | 0 | ND |
| 2018 | ND | 2 | 0 | ND |
| 2019 | ND | 12 | 0 | ND |
ppb = parts per billion
State and national drinking water standards and health guidelines
EWG Health Guideline 6 ppb
The EWG Health Guideline of 6 ppb for diquat 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 cataracts.
EPA Maximum Contaminant
Level (MCL) 20 ppb
The legal limit for diquat, established in 1992, was based on a toxicity study in laboratory animals conducted in the 1980s.
ppb = parts per billion
All test results
| Date | Lab ID | Result |
|---|---|---|
| 2014-05-12 | 5810-032-0920 | ND |
| 2014-05-12 | 5810-017-1015 | ND |
| 2014-05-28 | 5810-012-0930 | ND |
| 2014-06-23 | 5810-010-0815 | ND |
| 2014-09-10 | 5810-032-1020 | ND |
| 2014-09-10 | 5810-017-0950 | ND |
| 2014-09-10 | 5810-010-0920 | ND |
| 2014-09-10 | 5810-012-0845 | ND |
| 2015-05-18 | 5810-002-0900 | ND |
| 2015-07-21 | 1610-001-1010 | ND |
| 2016-05-09 | 1610-015-0930 | ND |
| 2016-05-09 | 1610-016-0730 | ND |
| 2016-05-09 | 1610-008-0815 | ND |
| 2016-05-09 | 1610-009-0900 | ND |
| 2016-05-16 | 1610-043-0740 | ND |
| 2016-05-16 | 1610-040-0830 | ND |
| 2016-08-22 | 1610-009-0930 | ND |
| 2016-08-22 | 1610-015-1000 | ND |
| 2016-08-22 | 1610-008-0830 | ND |
| 2016-08-22 | 1610-016-0900 | ND |
| 2016-08-22 | 1610-043-0730 | ND |
| 2016-08-22 | 1610-040-0800 | ND |
| 2017-05-08 | 1610-017-0900 | ND |
| 2017-05-08 | 1610-032-0800 | ND |
| 2017-05-22 | 1610-012-0720 | ND |
| 2017-08-14 | 5867-017-0830 | ND |
| 2017-08-14 | 5867-032-0800 | ND |
| 2017-08-14 | 5867-012-0900 | ND |
| 2018-10-30 | 1610-001-0930 | ND |
| 2018-12-11 | 1610-001-0730 | ND |
| 2019-05-07 | 1610-040-0715 | ND |
| 2019-05-07 | 1610-043-0630 | ND |
| 2019-05-07 | 1610-016-0930 | ND |
| 2019-05-07 | 1610-015-0830 | ND |
| 2019-05-07 | 1610-009-0800 | ND |
| 2019-05-07 | 1610-008-1000 | ND |
| 2019-09-10 | 1610-040-1000 | ND |
| 2019-09-10 | 1610-016-0900 | ND |
| 2019-09-10 | 1610-043-0940 | ND |
| 2019-09-10 | 1610-015-0800 | ND |
| 2019-09-10 | 1610-009-0730 | ND |
| 2019-09-10 | 1610-008-0830 | ND |