1,4-Dioxane
Tract 180 Mutual Water Company
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.
Samples
Samples exceeding legal limit (MCL)
Samples exceeding
health guidelines
Testing results - average by year
| Year | Average result | Samples taken | Detections | Range of results |
|---|---|---|---|---|
| 2014 | 6.33 ppb | 7 | 7 | 4.30 ppb - 8.20 ppb |
| 2015 | 5.20 ppb | 5 | 4 | ND - 8.90 ppb |
| 2016 | 5.18 ppb | 8 | 8 | 3.60 ppb - 7.60 ppb |
| 2017 | 4.44 ppb | 8 | 8 | 3.60 ppb - 6.50 ppb |
| 2018 | 4.50 ppb | 8 | 8 | 3.40 ppb - 5.90 ppb |
| 2019 | 4.23 ppb | 8 | 8 | 3.00 ppb - 6.30 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 |
|---|---|---|
| 2014-01-27 | 9588-005-0953 | 5.80 ppb |
| 2014-01-27 | 9588-004-1012 | 8.00 ppb |
| 2014-04-15 | 9588-005-1010 | 5.50 ppb |
| 2014-04-15 | 9588-004-1035 | 7.90 ppb |
| 2014-07-31 | 9588-005-1410 | 4.60 ppb |
| 2014-07-31 | 9588-004-1445 | 8.20 ppb |
| 2014-12-15 | 9588-005-1003 | 4.30 ppb |
| 2015-01-28 | 9588-005-0949 | 6.00 ppb |
| 2015-04-30 | 9588-005-0952 | 4.60 ppb |
| 2015-05-21 | 9588-004-0900 | 8.90 ppb |
| 2015-08-07 | 9588-004-0949 | ND |
| 2015-08-07 | 9588-005-0928 | 6.50 ppb |
| 2016-03-23 | 9588-004-0946 | 5.70 ppb |
| 2016-03-23 | 9588-005-0938 | 3.60 ppb |
| 2016-06-20 | 9588-004-1005 | 7.60 ppb |
| 2016-06-20 | 9588-005-0955 | 4.20 ppb |
| 2016-07-19 | 9588-004-0958 | 6.40 ppb |
| 2016-07-19 | 9588-005-0949 | 5.10 ppb |
| 2016-10-10 | 9588-004-0913 | 5.00 ppb |
| 2016-10-10 | 9588-005-0903 | 3.80 ppb |
| 2017-01-17 | 9588-004-1006 | 4.50 ppb |
| 2017-01-17 | 9588-005-0947 | 3.70 ppb |
| 2017-04-28 | 9588-004-1010 | 3.90 ppb |
| 2017-04-28 | 9588-005-0945 | 3.60 ppb |
| 2017-07-10 | 9588-004-0943 | 4.60 ppb |
| 2017-07-10 | 9588-005-0927 | 3.90 ppb |
| 2017-10-06 | 9588-005-0915 | 6.50 ppb |
| 2017-10-06 | 9588-004-0924 | 4.80 ppb |
| 2018-01-16 | 9588-005-0955 | 4.90 ppb |
| 2018-01-16 | 9588-004-1008 | 5.90 ppb |
| 2018-04-19 | 9588-005-0947 | 3.80 ppb |
| 2018-04-19 | 9588-004-0959 | 4.50 ppb |
| 2018-07-24 | 9588-004-0955 | 4.70 ppb |
| 2018-07-24 | 9588-005-0935 | 3.40 ppb |
| 2018-10-16 | 9588-004-0954 | 5.00 ppb |
| 2018-10-16 | 9588-005-0940 | 3.80 ppb |
| 2019-01-24 | 9588-005-1000 | 4.00 ppb |
| 2019-01-24 | 9588-004-1010 | 5.50 ppb |
| 2019-05-14 | 9588-005-0850 | 3.50 ppb |
| 2019-05-14 | 9588-004-0905 | 6.30 ppb |
| 2019-08-23 | 9588-005-0940 | 3.00 ppb |
| 2019-08-23 | 9588-004-0950 | 4.10 ppb |
| 2019-10-28 | 9588-005-0940 | 3.20 ppb |
| 2019-10-28 | 9588-004-1010 | 4.20 ppb |