Menu

EWG's Tap Water Database — 2021 UPDATE

Donate

2,4-D

Aqua Pennsylvania Main System

2,4-D (2,4-dichlorophenoxyacetic acid) is a herbicide that can be applied directly to GMO corn and soy plants engineered to withstand this toxic chemical. Americans' exposures to 2,4-D from food and drinking water will likely increase in years to come as farmers plant more of these GMO crops. Read More.

2,4-D is an endocrine disruptor that interferes with thyroid hormones. The International Agency for Research on Cancer classifies 2,4-D as possibly carcinogenic to humans. In occupational studies, farmers exposed to 2,4-D tended to have higher incidences of damaged and malformed sperm. Laboratory animals exposed to 2,4-D during gestation are born underdeveloped and are more likely to have birth defects.

 

32

Samples

0

Samples exceeding legal limit (MCL)

0

Samples exceeding
health guidelines

Testing results - average by year

 
YearAverage resultSamples takenDetectionsRange of results
2013N/A00N/A
2014ND140ND
2015N/A00N/A
2016ND10ND
20170.107 ppb141ND - 1.50 ppb
2018ND20ND
2019ND10ND

ppb = parts per billion

State and national drinking water standards and health guidelines

EWG Health Guideline 20 ppb

The EWG Health Guideline of 20 ppb for 2,4-D 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 harm to internal organs.

EPA Maximum Contaminant
Level (MCL) 70 ppb

The legal limit for 2,4-D, established in 1991, was based on toxicity studies in laboratory animals conducted in the 1980s. This limit may not fully protect against harm to the nervous system, harm to the thyroid, and hormone disruption.

ppb = parts per billion

All test results

Date Lab ID Result
2014-04-23AE30432ND
2014-04-23AE30533ND
2014-04-23AE30433ND
2014-04-28AE30874ND
2014-04-28AE30899ND
2014-04-29AE31042ND
2014-07-212019295001ND
2014-07-212019297001ND
2014-07-222019998001ND
2014-07-232019999001ND
2014-07-232020000001ND
2014-07-242020244001ND
2014-07-242020242001ND
2014-11-262042265001ND
2016-08-1114739507ND
2017-05-1516098295ND
2017-05-1516098314ND
2017-05-15160982761.50 ppb
2017-05-1716098370ND
2017-05-1716098342ND
2017-05-1716098398ND
2017-05-2516099731ND
2017-08-1416569891ND
2017-08-1416569947ND
2017-08-1516569919ND
2017-08-1616571274ND
2017-08-1616571216ND
2017-08-1616571245ND
2017-10-0816883571ND
2018-01-152288832001ND
2018-04-162309265001ND
2019-04-153029045001ND