Diquat
South Island PSD
Diquat is a herbicide used on potato crops and aquatic weeds.
Testing results - average by year
Year | Average result | Samples taken | Detections | Range of results |
---|---|---|---|---|
2013 | N/A | 0 | 0 | N/A |
2014 | ND | 12 | 0 | ND |
2015 | N/A | 0 | 0 | N/A |
2016 | N/A | 0 | 0 | N/A |
2017 | N/A | 0 | 0 | N/A |
2018 | N/A | 0 | 0 | N/A |
2019 | ND | 11 | 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 |
---|---|---|
2014-02-04 | AD35237 | ND |
2014-02-04 | AD35252 | ND |
2014-02-04 | AD35253 | ND |
2014-02-04 | AD35231 | ND |
2014-04-14 | AD38359 | ND |
2014-04-14 | AD38360 | ND |
2014-04-14 | AD38364 | ND |
2014-04-14 | AD38365 | ND |
2014-04-14 | AD38374 | ND |
2014-04-14 | AD38376 | ND |
2014-04-14 | AD38377 | ND |
2014-04-22 | AD38691 | ND |
2019-09-11 | AE36990 | ND |
2019-09-11 | AE37008 | ND |
2019-09-11 | AE37010 | ND |
2019-09-12 | AE37131 | ND |
2019-09-17 | AE37328 | ND |
2019-09-17 | AE37326 | ND |
2019-09-18 | AE37423 | ND |
2019-09-18 | AE37429 | ND |
2019-09-18 | AE37442 | ND |
2019-11-13 | AE40103 | ND |
2019-11-13 | AE40114 | ND |