Speaker: Dr. Tony Gough

Company: Innospec

Title: 1,4-Dioxane – The Ever Recurring Topic!

Language: English

Abstract: 1,4-Dioxane is a trace impurity by-product which forms during the manufacture of certain surfactants that contain ethoxylate units such as alkyl ether sulfates and can therefore be found as a trace impurity in numerous household cleaning and personal care cleansing products containing these surfactants. Its presence in these products has been known since the 1970s and, although it is classed as a possible human carcinogen, at the low levels at which it can be present in these products it is thought not to pose any risk to consumers when using these products.

However, concerns over levels of 1,4-dioxane found in drinking water prompted the imposition of a severe restriction on the level that 1,4-dioxane can be present in homecare, I&I and personal care products in the USA (New York State) (1 ppm maximum starting on 1st January 2024) and severe restrictions have recently also been proposed on the level of 1,4-dioxane that will be permitted in surfactant raw materials produced or imported into EU countries.

Ethoxylated surfactants such as alcohol ethoxylates and SLES have been workhorse, highly efficient and economical surfactants for many applications for decades and have long histories of safe use. Indeed, there are no substitutes for them in the majority of the applications they are used it. It is therefore hoped that these trusted, respected and widely used surfactants will not eventually be legislated out of existence due to their trace 1,4-dioxane content. However, the restrictions imposed so far and the additional restrictions being proposed might motivate companies to modify their formulations to be ‘1,4-dioxane free’ where possible. This presentation will cover some options for formulators on the possibilities for this.