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E172Fine

Iron oxides

Group: Colours

Harm level2 of 5Low concern

In plain words

These are iron-based mineral colours in yellow, red, brown and black shades. You will meet them in small amounts in sweets, coatings, fillings or on some cheese rinds.

Where you find it: coatings, tablets, confectionery

Our recommendation

No need to avoid them.

Possible risks and effects

  • No relevant risk known at normal intake.

For experts

They are synthetically produced iron oxides and hydroxides with high stability to light and heat. They are absorbed only minimally from the gut. EFSA re-evaluated them in 2015 and saw no safety concern at reported uses; EU specifications limit impurities such as heavy metals.

Check another E-number

More from this group

E171Titanium dioxideE102TartrazineE104Quinoline yellowE110Sunset Yellow FCFE122Azorubine (carmoisine)E124Ponceau 4RE129Allura Red ACE120Carmine (cochineal)

This information is educational and based on EFSA assessments and available studies; it does not replace medical advice. With allergies, intolerances or illness, follow your doctor’s advice.