1,4-Dioxane
Sativa-L.A. County 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 | 1.55 ppb | 10 | 10 | 1.20 ppb - 2.50 ppb |
| 2015 | 1.75 ppb | 8 | 7 | ND - 2.60 ppb |
| 2016 | 1.80 ppb | 13 | 9 | ND - 7.40 ppb |
| 2017 | 0.920 ppb | 10 | 5 | ND - 2.00 ppb |
| 2018 | 0.900 ppb | 8 | 4 | ND - 1.90 ppb |
| 2019 | 1.26 ppb | 7 | 5 | ND - 1.90 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 |
|---|---|---|
| 2014-01-14 | 9588-002-1005 | 1.90 ppb |
| 2014-01-14 | 9588-005-0955 | 1.70 ppb |
| 2014-04-07 | 9588-002-1200 | 1.20 ppb |
| 2014-04-07 | 9588-005-1145 | 1.50 ppb |
| 2014-04-24 | 9588-002-1110 | 1.40 ppb |
| 2014-04-24 | 9588-005-1050 | 1.30 ppb |
| 2014-07-07 | 9588-005-1133 | 1.30 ppb |
| 2014-07-07 | 9588-002-1150 | 1.30 ppb |
| 2014-10-06 | 9588-005-1354 | 1.40 ppb |
| 2014-10-06 | 9588-002-1405 | 2.50 ppb |
| 2015-01-05 | 9588-002-1010 | 2.40 ppb |
| 2015-02-02 | 9588-002-1005 | 2.30 ppb |
| 2015-03-02 | 9588-005-1000 | 1.10 ppb |
| 2015-04-06 | 9588-005-0940 | ND |
| 2015-07-06 | 9588-005-1028 | 1.60 ppb |
| 2015-09-18 | 9588-002-0850 | 2.20 ppb |
| 2015-10-05 | 9588-005-1040 | 1.80 ppb |
| 2015-10-05 | 9588-002-1055 | 2.60 ppb |
| 2016-01-04 | 9588-002-1100 | 2.10 ppb |
| 2016-01-04 | 9588-005-1040 | ND |
| 2016-04-04 | 9588-002-1100 | 2.20 ppb |
| 2016-04-04 | 9588-005-1010 | 1.80 ppb |
| 2016-05-09 | 9588-002-1428 | 7.40 ppb |
| 2016-05-09 | 9588-005-1418 | 1.70 ppb |
| 2016-06-06 | 9588-002-1022 | 2.30 ppb |
| 2016-06-06 | 9588-005-1010 | 1.80 ppb |
| 2016-07-11 | 9588-002-1020 | 2.20 ppb |
| 2016-07-11 | 9588-005-1000 | ND |
| 2016-09-30 | 9588-001-1200 | ND |
| 2016-10-14 | 9588-002-1030 | 1.90 ppb |
| 2016-10-14 | 9588-005-1017 | ND |
| 2017-02-07 | 9588-005-1015 | ND |
| 2017-02-07 | 9588-002-1025 | 1.90 ppb |
| 2017-04-03 | 9588-002-0955 | 1.90 ppb |
| 2017-04-03 | 9588-005-0935 | ND |
| 2017-06-23 | 9588-001-0905 | ND |
| 2017-07-07 | 9588-005-1000 | ND |
| 2017-07-07 | 9588-001-0949 | ND |
| 2017-07-14 | 9588-002-1010 | 2.00 ppb |
| 2017-10-06 | 9588-002-0950 | 2.00 ppb |
| 2017-10-06 | 9588-005-1005 | 1.40 ppb |
| 2018-01-03 | 9588-005-1130 | ND |
| 2018-01-03 | 9588-002-1110 | 1.90 ppb |
| 2018-04-12 | 9588-005-1035 | ND |
| 2018-04-12 | 9588-002-1050 | 1.90 ppb |
| 2018-07-11 | 9588-005-0945 | ND |
| 2018-07-31 | 9588-002-0940 | 1.60 ppb |
| 2018-10-04 | 9588-005-1000 | ND |
| 2018-10-04 | 9588-002-0930 | 1.80 ppb |
| 2019-01-07 | 9588-005-0950 | 1.90 ppb |
| 2019-02-27 | 9588-002-1030 | 1.80 ppb |
| 2019-04-01 | 9588-005-0858 | ND |
| 2019-04-01 | 9588-002-0950 | 1.70 ppb |
| 2019-07-01 | 9588-005-0920 | ND |
| 2019-07-01 | 9588-002-0957 | 1.60 ppb |
| 2019-10-24 | 9588-002-0940 | 1.80 ppb |