Glycerol (E 422) impurities and proposed specification limits
What it found
The EFSA Panel assessed impurities in commercial glycerol (E 422) and proposed lower limits for toxic elements and a numerical limit for acrolein.
The assessment used analytical data from industry and exposure calculations, not new studies in people or animals.
What they found
Toxic elements in samples
In 18 commercial samples of E 422, levels of arsenic, lead, mercury and cadmium were all below the limits of detection reported by the laboratories. The detection limits varied widely between labs.
Toxic elements at current limits
If arsenic, lead, mercury and cadmium were present at the current EU specification limits, the calculated exposure would be of concern. For lead and arsenic the margins of exposure would be too low, and for mercury and cadmium the exposure would represent more than 50% of the tolerable weekly intake.
Toxic elements at lower levels
If the limits were based on the highest detection limit reported or on the lowest detection limit multiplied by 10, the margin of exposure for arsenic would still be too low, but the other three elements would not give rise to concern.
Acrolein levels and exposure
Acrolein was found in samples at levels from below 0.5 mg/kg up to 3.1 mg/kg. If acrolein were present at 3 or 5 mg/kg, exposure from E 422 could reach up to 18% or 30% of the provisional tolerable concentration for acrolein.
3-MCPD exposure
Free 3-MCPD at the current specification limit of 0.1 mg/kg would give rise to exposure that is only a low percentage of the tolerable daily intake for 3-MCPD and its fatty acid esters. The Panel said this does not give rise to a health concern.
Manufacturing process
Industry stated that glycerol for E 422 is made only from vegetable oils and fats, either directly or from crude glycerol from biodiesel production. The Panel recommended changing the definition of E 422 to reflect this and to require purification by distillation.
What the authors conclude
“The Panel concluded that the maximum limits in the EU specifications for the four toxic elements (arsenic, lead, mercury and cadmium) should be lowered based on actual levels in the commercial food additive E 422.”
Also in their conclusions
- They concluded that the maximum limits in the EU specifications for arsenic, lead, mercury and cadmium should be lowered based on actual levels in the commercial food additive E 422.
- They recommended setting a numerical limit value for acrolein in the specifications for E 422.
- They concluded that the technical data provided support an amendment of the specifications for glycerol (E 422).
How it was done
Glycerol (E 422) was re-evaluated in 2017, and EFSA recommended updating the EU specifications to include limits for impurities that could be present. The European Commission asked EFSA to check whether new data from industry could support those changes.
The Panel reviewed analytical data on impurities in commercial samples of E 422 submitted by two interested business operators. They calculated potential exposure to these impurities from the use of E 422 as a food additive and compared it with health-based guidance values.
What it can’t tell you
- This assessment is based on analytical data from industry and exposure calculations, not on studies in people or animals. It cannot show what health effects, if any, would occur in people from eating glycerol (E 422).
- The exposure calculations assume that impurities may be present up to certain limit values. Actual exposure depends on real levels in foods and how much glycerol people consume.
The paper
- Title
- Follow-up of the re-evaluation of glycerol (E 422) as a food additive
- Type
- Scientific opinion of the European Food Safety Authority
- Summarised from
- Full text
- Licence
- CC BY-ND. Words in quotation marks are the authors’; the rest is our summary.
- Cite
- EFSA Panel on Food Additives and Flavourings (FAF), Younes M, Aquilina G, et al (2022). Follow-up of the re-evaluation of glycerol (E 422) as a food additive. EFSA journal. European Food Safety Authority. doi:10.2903/j.efsa.2022.7353Free full textPubMed 35770238DOI
Summary written 26 Sep 2026. Check it against the paper before it changes what you eat. How we summarise papers · Report an error