Know Your Environment. Protect Your Health.

Diquat

Summit Township Water Authority

NOTE: Summit Township Water Authority purchases water from Erie City Water Authority which is required to test for diquat. Sample information shown below was taken by Erie City Water Authority.

Diquat is a herbicide used on potato crops and aquatic weeds.

 

14

Samples

0

Samples exceeding legal limit (MCL)

0

Samples exceeding
health guidelines

Testing results - average by year

 
YearAverage resultSamples takenDetectionsRange of results
2018ND10ND
2019ND40ND
2020ND60ND
2021N/A00N/A
2022N/A00N/A
2023ND30ND

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

NOTE: Summit Township Water Authority purchases water from Erie City Water Authority which is required to test for diquat. Sample information shown below was taken by Erie City Water Authority.

Date Lab ID Result
2018-01-083849224ND
2018-05-213941484ND
2018-08-214030515ND
2019-05-214302822ND
2019-09-104415506ND
2019-11-184489102ND
2020-04-0122141721.00ND
2020-05-1822336497.00ND
2020-08-2622923665.00ND
2020-09-2323112736.00ND
2023-04-0428825998.00ND
2023-04-1828826400.00ND
2023-08-0929625435.00ND
2023-09-1429816652.00ND