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What Is It?

1,4-dioxane (sometimes just called dioxane) is found in products from personal care to laundry detergent, but it’s not an intentionally-added ingredient. It’s a contaminant that’s created when certain common ingredients are mixed together.

1,4-dioxane is an expected contaminant from a process called ethoxylation, when ethylene oxide is added to other ingredients to make them less harsh. A good example of this is sodium lauryl sulfate, which is harsh on skin. It’s often ethoxylated to convert it to sodium laureth sulfate; 1,4-dioxane is created in the process and contaminates the sodium laureth sulfate.

Most often found in products that suds, like shampoos, shower gels, dish soaps, and laundry detergents.1,4-dioxane has also been found in toothpastes, mouthwashes, deodorant, and hair dyes.

The Health Concern

1,4-dioxane is listed as a known or probable carcinogen by several scientific agencies, including appearing on California’s Proposition 65 list as linked to cancer, as a known animal carcinogen by the National Toxicology Program, and as a likely human carcinogen by the U.S. Environmental Protection Agency (EPA). According to the EPA, it’s also present in groundwater, ambient air, and indoor environments, in addition to showing up in products we use on a daily basis.

It is also on the EPA’s list of top ten chemicals for evaluation under the updated Toxic Substances Control Act. The EPA is required to review existing chemicals to determine “whether they present an unreasonable risk of injury to health or the environment.” If the answer is yes, the EPA has to place restrictions on or ban that chemical.

It’s estimated that the EPA may take up to five years to evaluate and regulate these first ten chemicals. A faster solution is to learn to avoid it in products in the meantime.

How to Avoid It

Read labels on products like shampoo, bubble bath, liquid soaps, and laundry detergents to avoid 1,4-dioxane. It won’t appear on ingredient lists because it’s not intentionally-added; however, you can avoid the chemicals that are commonly contaminated with it:

  • Sodium laureth sulfate
  • PEG compounds (usually listed as “PEG” followed by a number)
  • Chemicals that end in “eth” (denotes ethoxylation), like ceteareth and oleth
  • Try lathering and washing by simply using castile soap without any fragrance.
  • Look for the USDA Organic certification, which doesn’t allow ethoxylation processes, and the MADE SAFE seal.