Study on the occurrence of pesticide residues in fruit-based soft drinks from the EU market and morocco using liquid chromatography–mass spectrometry

While a plethora of regulation is available for pesticide control in fruits, vegetables, baby food or drinking water, scarce attention is still devoted to derivate products, which may contain these commodities as an ingredient, such as fruit-based soft drinks. A recent study (García-Reyes, Gilbert-López, Molina-Díaz, & Fernández-Alba, 2008) revealed the presence of relatively large concentrations of pesticides on a study carried out on 100 fruit-based soft drink samples, purchased from 15 different countries. In this work, a follow-up study on the occurrence of multiclass pesticides in fruit-based soft drinks is presented. This new monitoring program was undertaken on fruit-based soft drink samples from different European Union countries and also from Morocco. To accomplish the monitoring program, a liquid chromatography electrospray time-of-flight mass spectrometry method was used for the determination of 30 representative multiclass pesticides in fruit-based soft drinks, including the most frequently detected post-harvest fungicides. Sample treatment was based on solid-phase extraction (SPE) using polymer-based SPE cartridges. The identification and confirmation of the compounds was based on retention time and accurate mass measurements of the protonated molecules ([M + H]+) and their main fragment ions. Isotopic profile was also used for the confirmation of compounds containing halogen atoms in their structure (e.g. imazalil, prochloraz). The proposed method was successfully applied to 94 fruit-based soft drink samples obtained during 2009–2010 from 10 European countries and from Morocco. Residues of up to eleven different pesticides were detected. As in the previous studies, soft drink samples addressed pesticide residues in the μg L⁻¹ concentration level (from 0.1 to 36.1 μg L⁻¹), particularly from post-harvest fungicides that are usually present in the peel of citrus fruits (carbendazim, imazalil, imazalil metabolite, prochloraz, thiabendazole and buprofezin). Therefore, the exposure to these chemicals through these beverages still remains (90% of positive samples in the present study) and unambiguous specific regulations are still to be established.