Pesticide residue levels in strawberry processing by-products that are rich in ellagitannins and an assessment of their dietary risk to consumers

Background: According to many scientific studies, ellagitannins are beneficial for human health. One of the sources of these compounds is strawberry press-cake. This material can be used for the production of dietary fiber or ellagitannin preparations. The health safety of press cake and the preparations that are rich in ellagitannins obtained from it depend on pesticide residue levels, mainly fungicides, which are used for strawberry protection. Aim: The aim of the work was a dietary risk assessment measured by the %ADI (acceptable daily intake) and MOE (margin of exposure) associated with the presence of pesticide residues for the consumption of strawberry processing by-products containing an amount of ellagitannins equivalent to amount present in 100 g of fresh strawberries. In our study, we investigated the contents of pesticides that are approved for use against strawberry diseases and pests. Results: The total contents of pesticides in strawberry press-cake seeds (SPCS), exhausted strawberry flesh (ESF) and strawberry ellagitannin preparation (SEP) were 2143, 13,464 and 20,225 μg/kg, respectively. The analyzed products were dominated by fungicides as 96% of the total content of the tested pesticides. In the tested samples, we detected 11 fungicides and 3 insecticides. The dietary risk to consumer health, which depends on the presence of pesticide residues, in %ADI of daily consumption of ellagitannins (as dried extract (SEP), seeds (SPCS) or flesh (ESF)) ranged from 0.2% to 4.1% in a dose that was equivalent to 100 g of strawberries. Conclusion: Although the pesticide residue contents in strawberry by-products are higher than in fresh fruits, the suggested doses of the by-products are lower. Therefore, the dietary risk to consumers from strawberry by-products is comparable to that from fresh fruits.