1,4-Dioxane
High ConcernAlso known as
1,4-dioxane1 4 dioxanedioxanediethylene dioxide
The concern
IARC Group 2B possible carcinogen. Not added intentionally — a byproduct of ethoxylation in ingredients like SLES, PEG compounds, and sodium laureth sulfate. Found in many shampoos and liquid soaps. California requires labelling above 10 ppm.
What to look for on labels
This ingredient may appear under any of the following names or codes on product labels:
- 1,4-Dioxane
- 1,4-dioxane
- 1 4 dioxane
- dioxane
- diethylene dioxide
Data sourced from IARC, FDA, EFSA, WHO and EWG public data. For informational purposes only. This does not constitute medical or legal advice.