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Tuning the Acidity of Pt/ CNTs Catalysts for Hydrodeoxygenation of Diphenyl Ether
Published on: August 17, 2019
Smoked fish products available in European markets: Human exposure to polybrominated diphenyl ethers and their
Rebeca Cruz1, Zita E Martins1, António Marques2
1LAQV/REQUIMTE, Laboratório de Bromatologia e Hidrologia, Faculdade de Farmácia, Universidade do Porto, Rua de Jorge Viterbo, Ferreira 228, 4050-313, Porto, Portugal.
Abstract:
Food safety is continuously threatened by numerous contaminants including those originated from environmental pollution, such as PolyBrominated Diphenyl Ethers (PBDEs). In the present study, PBDEs and their biologically active metabolites - the methoxylated PBDEs (MeO-PBDEs) - were determined in several smoked seafood products (N = 30) acquired in the European market. The analyses were performed by an environmental-friendly method comprising a "Quick, Easy, Cheap, Effective, Rugged, and Safe" (QuEChERS)-based extraction followed by gas chromatography (tandem) mass spectrometry. At least one congener of each class of these flame retardants were detected in 80% of the samples assessed herein. Whenever above the limits of quantification, total PBDEs ranged from 0.21 to 64.49 μg kg-1, while MeO-PBDEs varied between 1.14 and 163.48 μg kg-1, on a wet weight basis. All smoked cod liver samples presented the highest degree of contamination, where a 100 g portion represented 12% of the PBDEs provisional tolerable weekly intake, as defined by the European food safety authority. Additionally, all tolerable daily intake percentages were below 0.2%, thus indicating no cause for concern for individuals exposed to PBDEs through consumption of smoked seafood products. Finally, multivariate partial least squares regression clarified the relationship between product characteristics and instrumental data, allowing to understand which variables caused greater influence on the contamination level of smoked products.
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