Diquat
Ely Municipal Water Department
Diquat is a herbicide used on potato crops and aquatic weeds.
15
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 | 0.575 ppb | 4 | 1 | ND - 2.30 ppb |
| 2017 | ND | 6 | 0 | ND |
| 2018 | ND | 1 | 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 |
|---|---|---|
| 2015-03-11 | 201503170492 | ND |
| 2015-10-15 | 201510200094 | ND |
| 2016-09-08 | 6I13035-05 | ND |
| 2016-09-08 | 6I13035-04 | 2.30 ppb |
| 2016-12-01 | 6L06022-01 | ND |
| 2016-12-01 | 201612070190 | ND |
| 2017-02-23 | 201703010881 | ND |
| 2017-09-14 | 201709191269 | ND |
| 2017-09-14 | 201709191268 | ND |
| 2017-09-14 | 201709191272 | ND |
| 2017-09-14 | 201709191270 | ND |
| 2017-09-14 | 201709191271 | ND |
| 2018-07-19 | 201807240558 | ND |
| 2019-08-14 | 201908190150 | ND |
| 2019-09-26 | 201910010466 | ND |