1,4-Dioxane
Suburban Water Systems - San Jose Hills
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 |
|---|---|---|---|---|
| 2013 | 0.0315 ppb | 11 | 3 | ND - 0.150 ppb |
| 2014 | 0.0308 ppb | 11 | 3 | ND - 0.150 ppb |
| 2015 | N/A | 0 | 0 | N/A |
| 2016 | N/A | 0 | 0 | N/A |
| 2017 | N/A | 0 | 0 | N/A |
| 2018 | N/A | 0 | 0 | N/A |
| 2019 | N/A | 0 | 0 | N/A |
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 |
|---|---|---|
| 2013-07-17 | 3G17071-07A | ND |
| 2013-07-17 | 3G17071-03A | 0.150 ppb |
| 2013-07-17 | 3G17071-09A | ND |
| 2013-07-17 | 3G17071-01A | 0.110 ppb |
| 2013-07-17 | 3G17071-05A | ND |
| 2013-07-17 | 3G17071-11A | ND |
| 2013-07-18 | 3G18052-01A | 0.0870 ppb |
| 2013-07-25 | 3G25022-01A | ND |
| 2013-10-24 | 3J24046-01A | ND |
| 2013-10-24 | 3J24046-03A | ND |
| 2013-10-29 | 3J29008-01A | ND |
| 2014-01-17 | 4A17030-01A | ND |
| 2014-01-21 | 4A21011-11A | ND |
| 2014-01-21 | 4A21011-03A | 0.110 ppb |
| 2014-01-21 | 4A21011-09A | ND |
| 2014-01-21 | 4A21011-07A | ND |
| 2014-01-21 | 4A21011-01A | ND |
| 2014-01-21 | 4A21011-05A | ND |
| 2014-04-14 | 4D14035-01A | ND |
| 2014-04-16 | 4D16085-01A | 0.150 ppb |
| 2014-09-25 | 4I25064-01A | 0.0790 ppb |
| 2014-12-04 | 4L04105-01A | ND |