Chapter 6: Preservatives
Potassium sorbate
- Made from a hazardous chemical
- Contaminant risk
The worst fact: it's one of the mildest here. The worst we found is that it can rarely cause a skin allergy.
Why brands use it: it's food-approved and gentle.
Take care if: you're allergic to sorbic acid.
Comes from: sorbic acid made from ketene and crotonaldehyde (2-butenal), then neutralised with potash. Australia classes crotonaldehyde as "May cause genetic defects". That doesn't mean it's in the product, but it's not a great starting point for something you clean with.
Myth check: "it comes from berries": sorbic acid was first made from rowan-berry oil in 1859, but today it's made in a factory.
Contaminants: as it ages, it can break down into crotonaldehyde and similar compounds. How much ends up in a product isn't known.
Fair to say: it's on the US EPA's safer list (green).
Correct as of November 2026. What the badges mean
Sources
- Safe Work Australia. Hazardous Chemical Information System (HCIS): classifications for each chemical and for benzene, ethylene oxide, toluene, phenol and benzyl chloride. hcis.safeworkaustralia.gov.au
- Dendooven E et al. Sorbic acid and potassium sorbate allergy. Contact Dermatitis 2021 (PMID 33656744).
The full source list is at the end of Chapter 6.