Leaching of postharvest pesticides from lemon fruits into liquid foodstuffs.

Abstract

The transfer of postharvest fungicides from citrus peel into foods is a poorly characterised exposure pathway. This study assessed the migration of imazalil (IMZ), thiabendazole (TBZ) and pyrimethanil (PMT) from lemon peel into altogether 25 commonly consumed beverages and soups under everyday use conditions. All fungicides were detectable in every matrix. Leaching efficiencies spanned more than three orders of magnitude, ranging from approximately 1 to 540 ‰ of the original residue load. PMT consistently showed the highest migration across matrices. Alcohol content moderately increased PMT transfer, whereas higher dry matter reduced TBZ and PMT migration; temperature showed no consistent effect. These findings demonstrate that matrix composition strongly influences residue mobility. Although resulting concentrations remained well below regulatory limits, matrix-dependent leaching may contribute to low-level consumer exposure, when untreated lemon peel is frequently used in foods or drinks.