Menu

EWG's Tap Water Database — 2019 UPDATE

Donate

Diquat

City of Scottsdale

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

 

51

Samples

0

Samples exceeding legal limit (MCL)

0

Samples exceeding
health guidelines

Testing results - average by year

 
YearAverage resultSamples takenDetectionsRange of results
2012ND40ND
2013ND40ND
2014ND210ND
2015ND30ND
2016N/A00N/A
2017ND190ND

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
2012-03-072030728-01ND
2012-05-312060057-01ND
2012-09-122091058-01ND
2012-10-302110088-01ND
2013-03-123030817-01ND
2013-06-033060187-01SND
2013-09-043090390-01ND
2013-11-213111810-01ND
2014-02-054020547-04SND
2014-02-054020547-03SND
2014-02-054020547-02SND
2014-02-054020547-01ND
2014-02-114020994-01ND
2014-02-124020997-01SND
2014-02-134021207-02SND
2014-02-134021207-01SND
2014-03-134031189-01SND
2014-06-034060399-01ND
2014-08-054080531-01ND
2014-08-054080529-01ND
2014-08-054080527-01ND
2014-08-074080785-03ND
2014-08-074080785-02ND
2014-08-074080785-01ND
2014-08-144081396-01ND
2014-08-214081971-01ND
2014-08-264082445-01ND
2014-08-274082450-01ND
2014-11-10201411100040SND
2015-01-265012122-01ND
2015-06-15201506150242SND
2015-07-28201507290355SND
2017-01-23201701230480SND
2017-01-31201701310419SND
2017-03-13201703130443SND
2017-04-11201704121085SND
2017-04-18201704180733SND
2017-05-03201705030393SND
2017-05-03201705030386SND
2017-05-11201705110565SND
2017-05-25201705250273SND
2017-08-09201708090677SND
2017-10-02201710020518SND
2017-10-10201710100211SND
2017-10-10201710100207SND
2017-10-23201710230327SND
2017-10-31201711010965SND
2017-10-31201711010947SND
2017-11-01201711010961SND
2017-11-01201711010957SND
2017-11-09201711090343SND