Diquat
City of Norfolk
Diquat is a herbicide used on potato crops and aquatic weeds.
48
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 | 8 | 0 | ND |
| 2016 | ND | 8 | 0 | ND |
| 2017 | ND | 8 | 0 | ND |
| 2018 | ND | 8 | 0 | ND |
| 2019 | ND | 8 | 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 |
|---|---|---|
| 2014-02-11 | 201402120489-DIQ | ND |
| 2014-02-11 | 201402120483-DIQ | ND |
| 2014-05-13 | 201405140544-DIQ | ND |
| 2014-05-13 | 201405140546-DIQ | ND |
| 2014-08-12 | 201408130296-DIQ | ND |
| 2014-08-12 | 201408130294-DIQ | ND |
| 2014-11-12 | 201411130557-DIQ | ND |
| 2014-11-12 | 201411130833-DIQ | ND |
| 2015-02-10 | 460260-EUROFINS | ND |
| 2015-02-10 | 460260-EUROFINS | ND |
| 2015-05-12 | 460260-EUROFINS | ND |
| 2015-05-12 | 460260-EUROFINS | ND |
| 2015-08-11 | 460260-EUROFINS | ND |
| 2015-08-11 | 460260-EUROFINS | ND |
| 2015-11-09 | 460260-EUROFINS | ND |
| 2015-11-09 | 460260-EUROFINS | ND |
| 2016-02-09 | 201602100120-DIQ | ND |
| 2016-02-09 | 201602100122-DIQ | ND |
| 2016-05-10 | 201605110161-DIQ | ND |
| 2016-05-10 | 201605110160-DIQ | ND |
| 2016-08-09 | 201608110693-DIQ | ND |
| 2016-08-09 | 201608100233-DIQ | ND |
| 2016-11-08 | 201611090228-DIQ | ND |
| 2016-11-08 | 201611090230-DIQ | ND |
| 2017-02-14 | 201702151127-DIQ | ND |
| 2017-02-14 | 201702151042-DIQ | ND |
| 2017-05-09 | 201705100790-DIQ | ND |
| 2017-05-09 | 201705100872-DIQ | ND |
| 2017-08-08 | 201708100347-DIQ | ND |
| 2017-08-08 | 201708091172-DIQ | ND |
| 2017-11-14 | 201711151069-DIQ | ND |
| 2017-11-14 | 201711150304-DIQ | ND |
| 2018-02-13 | 201802151032-DIQ | ND |
| 2018-02-13 | 201802150969-DIQ | ND |
| 2018-05-08 | 201805090974-DIQ | ND |
| 2018-05-08 | 201805091234-DIQ | ND |
| 2018-08-14 | 201808160459-DIQ | ND |
| 2018-08-14 | 201808160579-DIQ | ND |
| 2018-11-13 | 201811140123-DIQ | ND |
| 2018-11-13 | 201811140388-DIQ | ND |
| 2019-02-12 | 201902130366-DIQ | ND |
| 2019-02-12 | 201902130449-DIQ | ND |
| 2019-05-14 | 201905150501-DIQ | ND |
| 2019-05-14 | 201905150578-DIQ | ND |
| 2019-08-13 | 201908140712-DIQ | ND |
| 2019-08-13 | 201908150787-DIQ | ND |
| 2019-11-12 | 201911130679-DIQ | ND |
| 2019-11-12 | 201911130523-DIQ | ND |