1,4-Dioxane
Silverdale Water District 16
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 | ND | 11 | 0 | ND |
| 2015 | ND | 11 | 0 | ND |
| 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 |
| 2020 | N/A | 0 | 0 | N/A |
| 2021 | N/A | 0 | 0 | N/A |
| 2022 | N/A | 0 | 0 | N/A |
| 2023 | N/A | 0 | 0 | N/A |
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 |
|---|---|---|
| 2014-12-08 | 201412090508AM | ND |
| 2014-12-08 | 201412090605AM | ND |
| 2014-12-08 | 201412090767AM | ND |
| 2014-12-08 | 201412090590AM | ND |
| 2014-12-08 | 201412090583AM | ND |
| 2014-12-08 | 201412090603AM | ND |
| 2014-12-09 | 201412100830AM | ND |
| 2014-12-09 | 201412100442AM | ND |
| 2014-12-09 | 201412100776AM | ND |
| 2014-12-10 | 201412110884AM | ND |
| 2014-12-10 | 201412110237AM | ND |
| 2015-06-16 | 201506170352AM | ND |
| 2015-06-16 | 201506170384AM | ND |
| 2015-06-16 | 201506170375AM | ND |
| 2015-06-16 | 201506170589AM | ND |
| 2015-06-16 | 201506170403AM | ND |
| 2015-06-17 | 201506180486AM | ND |
| 2015-06-17 | 201506180429AM | ND |
| 2015-06-17 | 201506180469AM | ND |
| 2015-06-17 | 201506180501AM | ND |
| 2015-06-17 | 201506180490AM | ND |
| 2015-06-17 | 201506190057AM | ND |