1,4-Dioxane
Downey Water Department
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.
Testing results - average by year
Year | Average result | Samples taken | Detections | Range of results |
---|---|---|---|---|
2014 | N/A | 0 | 0 | N/A |
2015 | 1.64 ppb | 9 | 9 | 0.540 ppb - 2.80 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 |
---|---|---|
2015-02-24 | B5B2374-04 | 1.30 ppb |
2015-02-24 | B5B2374-07 | 1.70 ppb |
2015-02-24 | B5B2374-13 | 0.540 ppb |
2015-02-24 | B5B2374-01 | 2.70 ppb |
2015-02-24 | B5B2374-10 | 2.80 ppb |
2015-08-13 | B5H1452-04 | 1.90 ppb |
2015-08-13 | B5H1452-07 | 2.20 ppb |
2015-08-13 | B5H1452-10 | 0.550 ppb |
2015-08-13 | B5H1452-01 | 1.10 ppb |