1,4-Dioxane
Kent Water District 1
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 |
|---|---|---|---|---|
| 2018 | N/A | 0 | 0 | N/A |
| 2019 | N/A | 0 | 0 | N/A |
| 2020 | ND | 1 | 0 | ND |
| 2021 | 0.148 ppb | 6 | 5 | ND - 0.240 ppb |
| 2022 | ND | 9 | 0 | ND |
| 2023 | ND | 6 | 0 | ND |
ppb = parts per billion
State, National, and Health Guidelines for Drinking Water
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 |
|---|---|---|
| 2020-10-15 | CG97560 | ND |
| 2021-04-13 | CH98150PFO | 0.210 ppb |
| 2021-04-21 | CH99466PFO | 0.210 ppb |
| 2021-05-06 | CI25412PFOA | 0.230 ppb |
| 2021-09-17 | CJ31770 | ND |
| 2021-11-30 | CJ88191 | 0.240 ppb |
| 2021-11-30 | CJ88192 | 0.000200 ppb |
| 2022-03-18 | CK88130PFO | ND |
| 2022-05-09 | CL28454 | ND |
| 2022-05-09 | CL28453 | ND |
| 2022-06-06 | CL51649 | ND |
| 2022-06-06 | CL51650 | ND |
| 2022-08-08 | CM01023 | ND |
| 2022-08-08 | CM01022 | ND |
| 2022-12-06 | CM98165 | ND |
| 2022-12-06 | CM98166 | ND |
| 2023-02-20 | CN47644 | ND |
| 2023-02-20 | CN47643 | ND |
| 2023-05-22 | CO08298PFO | ND |
| 2023-05-22 | CO08297PFO | ND |
| 2023-07-18 | CO53322PFO | ND |
| 2023-07-18 | CO53323PFO | ND |