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Migration of trimellitic acid from epoxy anhydride can coatings into foods
1Official Food Control Authority of the Canton of Zurich, Switzerland.
Abstract:
The migration of trimellitic acid and its esters from epoxy anhydride coatings was determined in simulants as well as in canned foods. The most appropriate simulant was a combination of EC simulants B and C: 2% acetic acid/10% ethanol in water. The average migration into food was 900 microg kg(-1). This far exceeds the 50 microg kg(-1) for which the safety of trimellitic acid and its anhydride is ensured and the Swiss legal limit (QM(T) of 5 mg kg(-1) coating). Furthermore, much trimellitic acid migrated as (unidentified) esters, i.e. toxicological testing of free trimellitic acid is inadequate for the material that in reality migrates.
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