RESUMO
Processed plant-based foods, particularly high carbohydrate-containing foods, are among the greatest contributors to dietary acrylamide, a probable human carcinogen, uptake. Between 2009 and 2020, five surveys were conducted to determine acrylamide in high carbohydrate-containing foods in Canada. These surveys included sampling of potato and sweet potato chips, French fries, and frozen potato/sweet potato products, as a follow-up to our earlier surveys from 2002 - 2008. Samples were analyzed using isotope dilution (13C3-acrylamide) with LC-MS/MS. The highest mean acrylamide levels were found in sweet potato chips. Among potato chips (57 to 4660 ng g-1), one brand consistently showed the highest concentrations with wide variability. Acrylamide concentrations decreased over time in ready-to-eat French fries (from 480 to 358 ng g-1), and one brand showed a clear reduction temporally. Wide variations were observed among brands, among lots/outlets of same brands, and among different food chains. Acrylamide levels in potato chips decreased between 2009 and 2016 (504.3 ng g-1) relative to the period 2002 - 2008 (1096.9 ng g-1). The acrylamide trends observed in the products measured in the latest study indicate that food producers may have adopted mitigation strategies.
RESUMO
A method for the determination of 21 perfluorinated and 10 polyfluorinated alkyl substances (PFAS) was developed for application in different food matrices. Acetonitrile was used as the extraction solvent with solid phase extraction weak anion-exchange (SPE-WAX) clean up, with LC-MS/MS analysis using both surrogate and performance standards to correct for losses during sample preparation and matrix effects. The method has been evaluated in four different matrices (fish, pizza, chicken nuggets and spinach). Originally, the focus was to develop a method for foods commonly thought to be a source of PFASs (e.g. fish). It was expanded to include foods where PFAS exposure would be possible through their presence in grease-proof food packaging (e.g. pizza, chicken nuggets). Vegetables (lettuce) and fruit (tomato) have recently been considered as part of proficiency testing programmes, so the inclusion of some testing in a vegetable matrix (i.e. spinach) was also added to the testing. Limits of quantification ranged from 0.018 ng g-1 (L-PFDS) to 5.28 ng g-1 (FHEA), although method quantification limits for PFBA (12.4 ng g-1), 6:2 PAP (8.96 ng g-1) and 8:2 PAP (3.49 ng g-1) were elevated above instrumental limits owing to their consistent detection in reagent blank samples. PFAS analyses were strongly impacted by matrix, therefore the use of isotopically labelled internal standards was critical to the development of accurate results. The accuracy of the method using numerous proficiency testing schemes or interlaboratory comparison studies has shown the developed method to be successful with z-scores for all concerned analytes in all test matrices remaining within ±2.0, with the exception of PFBA in wheat flour which was -2.4.