Analies Dyjak, M.A. | Head of Policy and Perspectives

**Updated 9/21/2021 to include recent studies

What Is 1,4-Dioxane?

1,4-dioxane is a synthetic industrial chemical, typically used as a stabilizer for chlorinated solvents. It was historically used in the production of 1,1,1-trichloroethane (TCA), which was phased out in 1985 after scientists determined it to be an ozone-depleting substance. Today, 1,4-dioxane is not typically added directly to consumer products but can be an unintentional byproduct in certain plastics. It’s introduced as a trace contaminant in certain ingredients, most commonly detergents, foaming agents, emulsifiers and solvents, including Polyethylene Glycol or PEG.  

Is 1,4-Dioxane Regulated?

1,4-dioxane in drinking water is not federally regulated under the Safe Drinking Water Act, even though EPA has classified it as “likely to be carcinogenic to humans by all exposure routes.” There are health advisories in place but a Maximum Contaminant Level (MCL) does not exist. This means that unless a state has its own enforceable standard, utility providers are not required to remove it from drinking water. 1,4-dioxane is regulated by the Occupational Safety and Health Administration (OSHA) for indoor workplace air quality. 1,4-dioxane is on the fourth drinking water Contaminant Candidate List and is also part of the Third Unregulated Contaminant Monitoring Rule. In 2019, New York State became the first state to regulate 1,4-Dioxane by establishing Maximum Contaminant Limits (MCL) of 10 ppb in cosmetics, and 2 ppb in personal care and household cleaning products by 12/31/2022, which will be further reduced to 1 ppb by 12/31/2023.  

How Does 1,4-Dioxane Enter Drinking Water?

1,4-dioxane has contaminated drinking water through both groundwater and surface water. Many instances of groundwater contamination are a result of 1,4-dioxane being used in various manufacturing processes. According to the Agency for Toxic Substances and Disease Registry, 1,4-dioxane can easily travel into groundwater because it is extremely soluble in water and does not stick to soil particles. 

1,4-dioxane contamination on Long Island, New York was a result of routine spills or direct disposal of solvents to the ground from manufacturing operations between the 1950s to the 1990s. 

1,4-dioxane was used in the manufacture of medical filters in Ann Arbor, Michigan. The methods of waste disposal used between 1966 to 1986 resulted in 1,4-dioxane being released into the environment, causing widespread groundwater contamination. 1,4-dioxane in drinking water continues to be a concern for local residents, even decades after the pollution was first discovered and remediation was to have been taking place. 

1,4-Dioxane has also been released into surface water, both into rivers or public sewage systems. Sources of contamination include effluent from industrial facilities as well as wastewater treatment plants.   

1,4-Dioxane Health Effects In Drinking Water

1,4-dioxane can harm the eyes, skin, lungs, liver, and kidneys. As previously stated, 1,4-Dioxane is classified by the US EPA as a likely human carcinogen. Like other contaminants, the dose and duration of exposure affect the likelihood and severity of adverse 1,4-dioxane health effects.

Why is 1,4-Dioxane So Hard To Remove From Drinking Water?

1,4-Dioxane is completely soluble in water. It dissolves completely, even at high concentrations. It also does not readily evaporate. Traditional treatment methods are ineffective at removing 1,4-Dioxane from drinking water, so a few larger municipalities have begun to incorporate specialized methods for 1,4-Dioxane removal in their processes. These can be prohibitively expensive for smaller municipal water suppliers, so there is not likely to be a widespread solution for 1,4-Dioxane removal implemented any time soon.  

What Can I Do if I Have 1,4-Dioxane in My Water?

There are no federal testing standards for 1,4-Dioxane, so we are unable to provide removal data. Hydroviv’s filters have however been tested and certified by NSF to remove VOC’s with similar chemical properties to 1,4-Dioxane. Most submicron pore size carbon block filters are able to address 1,4-dioxane, with the exception of granular activated carbon. A slower flow rate will also assist the carbon block filter by ensuring enough contact time with the 1,4-Dioxane and the filtration media. For example, Hydroviv drinking water filters incorporate carbon into our submicron block and at our 1 gallon/minute flow rate.

Hydroviv's Science Team

Most people are aware of Volatile Organic Chemicals (VOCs) because they are frequently discussed when selecting paint for their home, but many people don't realize that they can contaminate drinking water supplies. This article provides a broad overview of VOCs as it pertains to water, and also gives practical advice on how to protect against them if a water supply becomes contaminated.

What Are Volatile Organic Chemicals (VOCs)?

By definition, VOCs are a class of chemicals that vaporize easily at normal air temperatures. VOCs are commonly found in household and industrial products including gasoline, solvents, cleaners and degreasers, paints, inks and dyes, and pesticides. For example, gasoline is a mixture of VOCs including benzene, toluene, and other hydrocarbons, which gives gasoline it’s familiar odor.

Can VOCs Contaminate Drinking Water?

Absolutely. In fact, the US Geological Survey (USGS) found in a recent study that VOCs are present in one-fifth of the nation's water supplies. For example, benzene, (a constituent of gasoline) commonly enters groundwater when it spills or leaks out of underground fuel tanks. Other examples of commonly detected VOCs in drinking water include dichloromethane (methylene chloride), an industrial solvent; trichloroethylene, used in septic system cleaners; and tetrachloroethylene (perchloroethylene), used in the dry-cleaning industry.

How Are VOCs In Drinking Water Regulated By EPA?

Because It would be impractical and costly for municipalities to test for every potential chemical that can be categorized as a VOC, EPA regulates a subset of chemicals that commonly contaminate water supplies. For example, benzene, one rather common constituent, is regulated with a maximum contaminant level set at 0.005 milligrams per liter (parts per million) and a goal of zero in drinking water. Water analysis can be requested if there is reason to suspect the presence of a specific VOC.

Private wells are not covered by EPA's regulations and testing is typically optional. While VOCs can be detected by odor at high concentrations, laboratory analysis is the only way to measure VOCs in drinking water at the regulatory limits. We highly recommend that all people who get water from private wells get their water tested by an accredited laboratory.

How To Remove VOCs From Drinking Water

High quality water filters are the only effective way to remove Volatile Organic Compounds in water. These water filter companies (including Hydroviv) test their filters against chemicals that are selected to represent a wide range of VOCs that commonly contaminate water supplies. The NSF Standard 53 protocol for VOC reduction requires manufacturers to test against the chemicals listed in the table below:

Table 1: List of chemicals that are part of the NSF 53 Standard Test For VOC Reduction

As always, we encourage you to reach out to our “Help No Matter What” technical support through live chat or email (support@hydroviv.com). Our team will provide science-backed advice on water quality and water filtration, even if you have no intention of buying a Hydroviv water filter.