1,4-Dioxane
Truckee Meadows Water Authority
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 |
|---|---|---|---|---|
| 2013 | 0.0185 ppb | 31 | 4 | ND - 0.300 ppb |
| 2014 | ND | 10 | 0 | ND |
| 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 | 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 |
|---|---|---|
| 2013-05-20 | 201305210059AM | 0.0930 ppb |
| 2013-05-20 | 201305210061AM | ND |
| 2013-05-20 | 201305210066AM | ND |
| 2013-05-20 | 201305210275AM | ND |
| 2013-05-22 | 201305230335AM | 0.300 ppb |
| 2013-05-22 | 201305230289AM | ND |
| 2013-05-22 | 201305230342AM | ND |
| 2013-05-22 | 201305230338AM | ND |
| 2013-06-04 | 201306050182AM | ND |
| 2013-06-04 | 201306050241AM | ND |
| 2013-06-11 | 201306120172AM | ND |
| 2013-06-11 | 201306120227AM | ND |
| 2013-06-11 | 201306120169AM | ND |
| 2013-06-11 | 201306120213AM | ND |
| 2013-06-11 | 201306120163AM | 0.0870 ppb |
| 2013-06-11 | 201306120229AM | ND |
| 2013-06-19 | 201306200250AM | ND |
| 2013-06-19 | 201306200126AM | ND |
| 2013-06-19 | 201306200239AM | ND |
| 2013-06-19 | 201306200243AM | ND |
| 2013-06-19 | 201306200237AM | ND |
| 2013-06-19 | 201306200268AM | ND |
| 2013-06-19 | 201306200241AM | ND |
| 2013-06-24 | 201306250077AM | ND |
| 2013-06-25 | 201306260226AM | ND |
| 2013-06-25 | 201306260231AM | ND |
| 2013-06-27 | 201306280176AM | ND |
| 2013-09-17 | 201309200267AM | ND |
| 2013-09-17 | 201309200263AM | 0.0940 ppb |
| 2013-11-25 | 201311270060AM | ND |
| 2013-12-16 | 201312180499AM | ND |
| 2014-03-05 | 201403070313AM | ND |
| 2014-04-22 | 201404250176AM | ND |
| 2014-04-22 | 201404250157AM | ND |
| 2014-04-22 | 201404250189AM | ND |
| 2014-04-22 | 201404250162AM | ND |
| 2014-04-29 | 201405020169AM | ND |
| 2014-04-29 | 201405020173AM | ND |
| 2014-04-29 | 201405020265AM | ND |
| 2014-04-29 | 201405020257AM | ND |
| 2014-06-09 | 201406110932AM | ND |