About the author:
Cristina Tuser is associate editor for WWD. Tuser can be reached at [email protected]
What is 1,4-dioxane?
1,4-dioxane is a synthetic industrial chemical that is miscible in water.
It is a by-product present in items including: paint strippers, dyes, greases, antifreeze, aircraft deicing fluids, and other consumer products. 1,4-dioxane may also be present in food supplements, packaging adhesives or on food crops treated with pesticides.
What is 1,4-dioxane Used for?
1,4-dioxane has been used to stabilize chlorinated solvents. It has recently been deemed by EPA as a contaminant of concern for many consumer and food products.
Research published in the National Library of Medicine shows that more than one-fifth of U.S. public drinking water supplies contain detectable levels of 1,4-dioxane.
Common commercial uses include in the manufacture of other chemicals, as a processing aid, in laboratory chemicals, and in adhesives and sealants.
Is 1,4-dioxane a Volatile Organic Compound (VOC)?
1,4-dioxane is a volatile organic compound (VOC) that can migrate rapidly in groundwater. It can also be considered a semi-volatile organic compound (SVOC) but due to its physical properties can not be easily purged as a VOC.
It has been reportable as a Toxics Release Inventory chemical under Section 313 of the Emergency Planning and Community Right-to-Know Act.
It is also a Hazardous Air Pollutant under the Clean Air Act and a hazardous substance under the Comprehensive Environmental Response, Compensation and Liability Act known more commonly in the industry as CERCLA.
Additionally, it was listed on the Safe Drinking Water Candidate Contaminant List and identified in the third Unregulated Contaminant Monitoring Rule.
Is 1,4-dioxane Harmful? Should I Worry About 1,4-dioxane?
1,4-dioxane may likely be a human carcinogen, and it has been found in groundwater at sites, creating treatment challenges. 1,4-dioxane is not readily biodegradable in the environment.
Exposure to this chemical may occur through contaminated food and water, dermal contact or inhalation of vapors (in the case of workers). According to the EPA, short-term exposure to high levels of 1,4-dioxane can result in: nausea, drowsiness, headache, and ENT irritation.
EPA recommends workers using 1,4-dioxane should properly use appropriate personal protective equipment (PPE) for health and safety. Currently there are no federal or state maximum contaminant levels for this chemical.
How do You Test for or Detect 1,4-dioxane?
Commercial laboratories use three methods to detect 1,4-dioxane: EPA 524.2 for drinking water, and EPA 8260 and 8270 for groundwater and hazardous waste.
EPA 8270 is most common and uses liquid-liquid extraction and isotope dilution by capillary column gas chromatography/mass spectrometry to detect its presence.
What Technologies Exist to Treat or Remediate 1,4-dioxane in Water?
Advanced oxidation process (AOP) is an effective treatment. AOP uses peroxide and ultraviolet light (UV) or ozone, which are proven to destroy 1,4-dioxane.
Chlorination is technically effective for its removal, but the byproducts that result from chlorination can be more toxic than 1,4-dioxane itself.
Wastewater treatment methods and conventional activated sludge methods are ineffective at removing 1,4-dioxane in wastewater.