1,4-Dioxane
Oyster Bay 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 | N/A | 0 | 0 | N/A |
| 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 | 0.207 ppb | 15 | 15 | 0.0470 ppb - 0.430 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 |
|---|---|---|
| 2019-01-15 | 7076661003 | 0.430 ppb |
| 2019-01-15 | 7076661002 | 0.380 ppb |
| 2019-01-15 | 7076661005 | 0.0640 ppb |
| 2019-01-15 | N-00585 | 0.0530 ppb |
| 2019-01-15 | 7076661004 | 0.0940 ppb |
| 2019-06-25 | 7095135005 | 0.0510 ppb |
| 2019-06-25 | 7095135002 | 0.430 ppb |
| 2019-06-25 | 7095135001 | 0.390 ppb |
| 2019-06-25 | 7095135004 | 0.0470 ppb |
| 2019-06-25 | 7095135003 | 0.110 ppb |
| 2019-09-18 | 70105359001 | 0.0470 ppb |
| 2019-09-18 | 70105359003 | 0.430 ppb |
| 2019-09-18 | 70105359002 | 0.400 ppb |
| 2019-09-18 | 70105359004 | 0.120 ppb |
| 2019-09-18 | 70105359005 | 0.0630 ppb |