1,4-DIOXANE

What is it?

“1,4-Dioxin (also referred as dioxin or p-dioxin) is a heterocyclic, organic, non-aromatic compound with the chemical formula C4H4O2.” Wikipedia

What are the effects?

This substance belongs to the groups:

1,4-Dioxane is prohibited for use in cosmetics in Canada and the European Union. Nevertheless it is still present in many cosmetic products but you will most likely not find it in the list of ingredients.

1,4-dioxane is a by product that is formed when an ingredient is ethoxylated; when ethylene oxide is added to a substance. There are ways to remove the generated 1,4 Dioxane but it is not all manufacturers who does that. It is not possible to determine if a product contains 1,4-dioxane by just looking at the ingredients, it needs to be tested in a laboratory. However, one can look at the ingredients and see if it is likely that the product is contaminated. All ingredients that are likely to be contaminated will be highlighted by Curious Chloride’s scanner.

The U.S. governmental Agency for Toxic Substances and Disease Registry (ATSDR) writes that “Many products on the market today (foods, pharmaceuticals, cosmetic products, detergents, etc.) contain 1,4-dioxane in very small amounts. However, some cosmetics, detergents, and shampoos may contain 1,4-dioxane at levels higher than recommended by the FDA for other products.”

The European Chemicals Agency (ECHA) classifies this substance as “highly flammable liquid and vapour, causes serious eye irritation, is suspected of causing cancer and may cause respiratory irritation.”

The International Agency for Research on Cancer writes that “1,4-Dioxane is possibly carcinogenic to humans … There is sufficient evidence in experimental animals for the carcinogenicity of 1,4-dioxane.”

The substance is on the Red List* from Campaign for Safe Cosmetics, a project of Breast Cancer Prevention Partners (previously the Breast Cancer Fund). They also list it as a probable carcinogen.

Possible contamination

As 1,4-Dioxane is an impurity in cosmetic products, it might not show on the ingredients list. These are some of the substances known to be contaminated:

* “The Red List includes chemicals found in personal care products that pose serious, chronic health concerns including cancer, hormone disruption, and reproductive and developmental harm. The list also flags chemicals that are banned or have use restrictions by the U.S. or other world governments, ingredients that adversely impact worker health, and ingredients that are widely used in products marketed to women of color.” – Campaign for Safe Cosmetics

How is it used?

The use of this chemical is mainly in the manufacture of other chemicals and as a reagent in laboratories. In cosmetic products*, it is found as an impurity and will most likely not be found in the list of ingredients.

1,4-Dioxane is formed when trying to reduce the risk of skin irritation of cosmetics, most commonly of petroleum based products. In a process called ethoxylation, ethylene oxide is added to make chemicals in cosmetics* less harsh and in this reaction an unwanted byproduct is created; 1,4-dioxane. Ethoxylation is a quite common practice to make chemicals milder and because of this 1,4-Dioxane can be found as an impurity in thousands of cosmetics, detergents, pharmaceuticals, natural health products, pesticides, food packaging and additives, etc.

There are ways to remove this unwanted byproduct in cosmetics but it is not all manufacturers who will do that. And unfortunately there is no way to know which products contain the chemical unless it is tested in a laboratory. The David Suzuki Foundation reports that 1,4-dioxane has been found also in organic products.

We use the European Commissions definition of Cosmetics:
“Cosmetics range from everyday hygiene products such as soap, shampoo, deodorant, and toothpaste to luxury beauty items including perfumes and makeup”.

Read about the other ingredients.

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