1,4-Dioxane
South Midway City Mutual Water Company
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 | N/A | 0 | 0 | N/A |
| 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 | 4.85 ppb | 4 | 4 | 4.10 ppb - 5.60 ppb |
| 2019 | 5.06 ppb | 5 | 5 | 4.80 ppb - 5.50 ppb |
| 2020 | 4.20 ppb | 4 | 4 | 3.80 ppb - 4.50 ppb |
| 2021 | 5.00 ppb | 3 | 3 | 4.40 ppb - 5.70 ppb |
| 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 |
|---|---|---|
| 2018-01-03 | CA3000825_002_002-201801030820 | 4.70 ppb |
| 2018-04-04 | CA3000825_002_002-201804040900 | 4.10 ppb |
| 2018-07-16 | CA3000825_002_002-201807160815 | 5.60 ppb |
| 2018-10-01 | CA3000825_002_002-201810011310 | 5.00 ppb |
| 2019-01-02 | CA3000825_002_002-201901020935 | 4.80 ppb |
| 2019-04-01 | CA3000825_002_002-201904011240 | 4.80 ppb |
| 2019-07-02 | CA3000825_002_002-201907020835 | 5.00 ppb |
| 2019-07-22 | CA3000825_002_002-201907221040 | 5.20 ppb |
| 2019-10-01 | CA3000825_002_002-201910010910 | 5.50 ppb |
| 2020-02-18 | CA3000825_002_002-202002181140 | 4.40 ppb |
| 2020-04-08 | CA3000825_002_002-202004081000 | 4.10 ppb |
| 2020-08-19 | CA3000825_002_002-202008191010 | 3.80 ppb |
| 2020-10-01 | CA3000825_002_002-202010010800 | 4.50 ppb |
| 2021-01-04 | CA3000825_002_002-202101041040 | 4.40 ppb |
| 2021-04-12 | CA3000825_002_002-202104121120 | 4.90 ppb |
| 2021-07-01 | CA3000825_002_002-202107010900 | 5.70 ppb |