Know Your Environment. Protect Your Health.

Diquat

Gulf County Water Department (lighthouse)

NOTE: Gulf County Water Department (lighthouse) purchases water from City of Port St. Joe which is required to test for diquat. Sample information shown below was taken by City of Port St. Joe.

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

 

4

Samples

0

Samples exceeding legal limit (MCL)

0

Samples exceeding
health guidelines

Testing results - average by year

 
YearAverage resultSamples takenDetectionsRange of results
2018N/A00N/A
2019N/A00N/A
2020ND10ND
2021ND20ND
2022ND10ND
2023ND10ND

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: Gulf County Water Department (lighthouse) purchases water from City of Port St. Joe which is required to test for diquat. Sample information shown below was taken by City of Port St. Joe.

Date Result
2020-05-26ND
2020-10-20ND
2022-10-12ND
2023-10-26ND