1,4-Dioxane
Dix Hills Water District
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 | 0.218 ppb | 10 | 5 | ND - 1.30 ppb |
| 2015 | 0.0875 ppb | 8 | 3 | ND - 0.320 ppb |
| 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 |
|---|---|---|
| 2014-10-21 | 11919 112014 | ND |
| 2014-10-22 | 78278 112014 | 0.170 ppb |
| 2014-10-22 | 78275 112014 | 0.460 ppb |
| 2014-10-22 | 78282 112014 | 1.30 ppb |
| 2014-11-20 | 78298 112014 | ND |
| 2014-11-20 | 90017 112014 | 0.0780 ppb |
| 2014-11-20 | 78302 112014 | ND |
| 2014-11-24 | 78295 112014 | ND |
| 2014-11-24 | 78293 112014 | 0.170 ppb |
| 2014-11-24 | 78288 112014 | ND |
| 2015-04-29 | 78282 042015 | ND |
| 2015-04-29 | 11919 042015 | 0.320 ppb |
| 2015-04-30 | 78275 072015 | ND |
| 2015-04-30 | 78278 072015 | 0.280 ppb |
| 2015-05-27 | 78302 072015 | ND |
| 2015-05-27 | 78293 072015.1 | 0.1000 ppb |
| 2015-05-29 | 78288 072015 | ND |
| 2015-05-29 | 90017 072015 | ND |