Diquat
California Water Service Company - Dixon
Diquat is a herbicide used on potato crops and aquatic weeds.
26
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 |
|---|---|---|---|---|
| 2014 | ND | 9 | 0 | ND |
| 2015 | ND | 8 | 0 | ND |
| 2016 | ND | 3 | 0 | ND |
| 2017 | N/A | 0 | 0 | N/A |
| 2018 | ND | 4 | 0 | ND |
| 2019 | ND | 2 | 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 |
|---|---|---|
| 2014-09-16 | 5810-005-1051 | ND |
| 2014-10-16 | 5810-008-1446 | ND |
| 2014-10-29 | 5810-006-0842 | ND |
| 2014-10-29 | 5810-002-1000 | ND |
| 2014-12-17 | 5810-007-1109 | ND |
| 2014-12-17 | 5810-005-1601 | ND |
| 2014-12-17 | 5810-003-1018 | ND |
| 2014-12-30 | 5810-004-1156 | ND |
| 2014-12-30 | 5810-002-1156 | ND |
| 2015-01-05 | 5810-006-1350 | ND |
| 2015-01-21 | 5810-002-0925 | ND |
| 2015-01-21 | 5810-008-1054 | ND |
| 2015-03-03 | 9590-002-0902 | ND |
| 2015-03-03 | 9590-007-0953 | ND |
| 2015-03-25 | 9590-008-0850 | ND |
| 2015-03-31 | 9590-009-1057 | ND |
| 2015-05-20 | 9590-003-0910 | ND |
| 2016-04-06 | 9590-017-1123 | ND |
| 2016-06-13 | 9590-020-1700 | ND |
| 2016-07-20 | 9590-017-1340 | ND |
| 2018-04-04 | 9590-002-0918 | ND |
| 2018-04-05 | 9590-008-1337 | ND |
| 2018-07-02 | 9590-002-1500 | ND |
| 2018-07-10 | 9590-008-1540 | ND |
| 2019-04-02 | 9590-017-1547 | ND |
| 2019-07-02 | 9590-017-1330 | ND |