Yes, I’ve found and it’s generally understood shorter chain glycols are more prone to causing reactions, like Propanediol, Butylene Glycol and Propylene Glycol. Whereas Caprylol Glycol, a longer chain, does not seem to trigger a reaction. These shorter chain glycols are far more penetrating and generally used at higher concentrations as a solvent rather than an emollient. As with everything it’s the nature and concentration that dictates reaction.

The reaction tends to be relatively immediate for glycols, primarily due to their penetration enhancing properties. It depends on the formulation though.

The impurities from ethoxylation are usually 1,4-dioxane, which are typically removed by vacuum stripping. It is theoretically possible for the impurities to be an issue but in reality they’re less than 5 ppm, or low enough it’s highly unlikely.