Diquat
Town of Queen Creek
Diquat is a herbicide used on potato crops and aquatic weeds.
45
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 | ND | 2 | 0 | ND |
| 2016 | ND | 10 | 0 | ND |
| 2017 | ND | 12 | 0 | ND |
| 2018 | ND | 13 | 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 |
|---|---|---|
| 2015-03-04 | 201503040378S | ND |
| 2015-07-21 | 201507210224S | ND |
| 2016-06-08 | 201606080206SE | ND |
| 2016-06-08 | 201606080206SD | ND |
| 2016-06-08 | 201606080206SC | ND |
| 2016-06-08 | 201606080206SB | ND |
| 2016-06-08 | 201606080206SA | ND |
| 2016-08-04 | 201608040131SB | ND |
| 2016-08-04 | 201608040131SA | ND |
| 2016-08-04 | 201608040131SC | ND |
| 2016-08-04 | 201608040131SD | ND |
| 2016-08-04 | 201608040131SE | ND |
| 2017-03-15 | 201703150359CS | ND |
| 2017-03-15 | 201703150359BS | ND |
| 2017-03-15 | 201703150359AS | ND |
| 2017-03-15 | 201703150357CS | ND |
| 2017-03-15 | 201703150357BS | ND |
| 2017-03-15 | 201703150357AS | ND |
| 2017-07-06 | 201707060528BS | ND |
| 2017-07-06 | 201707060557CS | ND |
| 2017-07-06 | 201707060557BS | ND |
| 2017-07-06 | 201707060557AS | ND |
| 2017-07-06 | 201707060528CS | ND |
| 2017-07-06 | 201707060528AS | ND |
| 2018-01-18 | 201801180389S | ND |
| 2018-04-24 | 201804250399SC | ND |
| 2018-04-24 | 201804250399SB | ND |
| 2018-04-24 | 201804250399SA | ND |
| 2018-05-30 | 201805310317SB | ND |
| 2018-05-30 | 201805310317SA | ND |
| 2018-07-18 | 201807180477S | ND |
| 2018-07-18 | 201807180477SA | ND |
| 2018-07-18 | 201807180477SB | ND |
| 2018-07-18 | 201807180477SD | ND |
| 2018-08-01 | 201808020191SB | ND |
| 2018-08-01 | 201808020191SA | ND |
| 2018-10-03 | 201810030298S | ND |
| 2019-02-13 | 201902130133SB | ND |
| 2019-02-13 | 201902130133SA | ND |
| 2019-06-03 | 201906030212SB | ND |
| 2019-06-03 | 201906030212SA | ND |
| 2019-07-25 | 201907250175S | ND |
| 2019-09-19 | 201909190002S | ND |
| 2019-10-24 | 201910240423SA | ND |
| 2019-10-24 | 201910240423SB | ND |