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EWG's Tap Water Database — 2021 UPDATE

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1,4-Dioxane

N Walpole Village District/low

1,4-Dioxane is a solvent classified by the EPA as a likely human carcinogen. It contaminates groundwater in many states due to industrial wastewater discharges, plastic manufacturing runoff and landfill runoff. Read More.

Animal studies show that 1,4-dioxane can target the liver, kidneys and respiratory system, and that prenatal exposure can harm the developing fetus. The State of California has set a Public Heatlh Goal of no more than 1 part per billion of 1,4-dioxane in drinking water. The state of Massachusetts sets a legal limit of 0.3 ppb, and New Hampshire's limit is 3 parts per billion. There is no national drinking water standard for this contaminant.

Click here to read more about 1,4-dioxane.

 

10

Samples

0

Samples exceeding legal limit (MCL)

10

Samples exceeding
health guidelines

Testing results - average by year

 
YearAverage resultSamples takenDetectionsRange of results
2014N/A00N/A
20152.75 ppb112.75 ppb
20162.10 ppb112.10 ppb
2017N/A00N/A
20180.733 ppb220.466 ppb - 1.000 ppb
20190.978 ppb660.580 ppb - 1.57 ppb

ppb = parts per billion

State and national drinking water standards and health guidelines

EWG Health Guideline 0.35 ppb

The EWG Health Guideline of 0.35 ppb for 1,4-dioxane was defined by the Environmental Protection Agency as a one-in-a-million lifetime risk of cancer. Values greater than one-in-a-million cancer risk level can result in increased cancer cases above one in a million people.

ppb = parts per billion

All test results

Date Lab ID Result
2015-01-19111031P2.75 ppb
2016-03-013603-130-12.10 ppb
2018-02-06118020473.011.000 ppb
2018-05-08118051004.010.466 ppb
2019-04-02119040309.010.580 ppb
2019-05-07119050910.011.47 ppb
2019-07-08119071054.011.57 ppb
2019-07-09119071053.010.590 ppb
2019-10-22119102615.010.890 ppb
2019-11-12119111258.010.770 ppb