Know Your Environment. Protect Your Health.

Diquat

Gurdon Waterworks

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

 
YearAverage resultSamples takenDetectionsRange of results
2018ND40ND
2019ND40ND
2020N/A00N/A
2021ND40ND
2022ND30ND
2023N/A00N/A

ppb = parts per billion

State, National, and Health Guidelines for Drinking Water

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
2018-01-2218025000708ND
2018-01-2218025000808ND
2018-04-2418115005408ND
2018-04-2418115005508ND
2019-01-2319024002008ND
2019-04-304280245ND
2019-08-0619220001808ND
2019-11-1819324000208ND
2021-03-0321063009402ND
2021-03-0321063009302ND
2021-04-0521098004008ND
2021-04-0521098004108ND
2022-01-1122013002608ND
2022-07-18810313201ND
2022-10-03O202442-QUA-1ND