ScanWise
E240 · Preservatives

Formaldehyde

High risk

Formaldehyde is classified by IARC as carcinogenic to humans. It is not permitted as a food additive.

Category
Preservatives
Vegan
Yes
Vegetarian
Yes

What it is

Formaldehyde is a highly reactive preservative and disinfectant, classified as a human carcinogen and banned from food.

How it is used in food

It kills essentially everything, which is what made it attractive as a preservative.

Commonly found in
  • Hard cheeses
  • Smoked fish
  • Sugar syrups

Health and safety

A confirmed human carcinogen (IARC Group 1), linked to nasopharyngeal cancer and leukaemia. It is not permitted in food anywhere it has been assessed.

Banned as a food additive in the EU, the US and internationally. IARC placed it in Group 1 in 2004; its permitted uses today are industrial and laboratory, not dietary.

Regulatory status

RegionStatusNotes
Australia & New Zealand
FSANZ
Not approved Not approved for general food use or historically banned due to safety concerns.
European Union
EFSA / European Commission
Not approved Not on the EU authorised list of food additives (Annex II).
United States
FDA (Food and Drug Administration)
Not approved Not approved for general food use or historically banned due to safety concerns.

Identification on labels

E-number
E240

Worth knowing

Small amounts occur naturally in food — apples, pears and several marine fish contain it — which is why a trace detection is not the same as adulteration.

Conclusion

A highly toxic, carcinogenic chemical. Completely banned.

References

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Entry last reviewed 2026-08-05.

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