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EWG's Tap Water Database — 2021 UPDATE

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Diquat

Miramar (East & West) Plants

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

 

16

Samples

0

Samples exceeding legal limit (MCL)

0

Samples exceeding
health guidelines

Testing results - average by year

 
YearAverage resultSamples takenDetectionsRange of results
2014ND40ND
2015ND20ND
20160.150 ppb21ND - 0.300 ppb
2017ND20ND
2018ND40ND
2019ND20ND

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 Result
2014-09-09ND
2014-09-09ND
2014-11-19ND
2014-11-19ND
2015-09-09ND
2015-09-10ND
2016-09-130.300 ppb
2016-09-13ND
2017-09-29ND
2017-09-29ND
2018-01-31ND
2018-01-31ND
2018-08-08ND
2018-08-08ND
2019-08-14ND
2019-08-14ND