Development of methods for halogen and sulfur determination, speciation and bioavailability assessment in seafood

• Ano de defesa: 2024
• Autor(a) principal: Balbinot, Fernanda Pitt
• Orientador(a): Mesko, Márcia Foster
• Tipo de documento: Tese
• Tipo de acesso: Acesso aberto
• Idioma: eng
• Instituição de defesa: Universidade Federal de Pelotas
• Programa de Pós-Graduação: Programa de Pós-Graduação em Química
• País: Brasil
• Palavras-chave em Português: Ion chromatography; Mass spectrometry; Microwave-induced combustion; Halogen bioavailability; PFAS speciation
• Área do conhecimento CNPq: CIENCIAS EXATAS E DA TERRA
• Link de acesso: http://guaiaca.ufpel.edu.br/xmlui/handle/prefix/14681

Seafood is one of the most widely consumed food classes worldwide. Among the elements that can be found in the seafood composition, halogens and sulfur can be mentioned. However, increasing pollution of water bodies harms the safety and quality of these foods, as well change the concentration of nutrients and other elements in them. In this sense, the goal of this thesis was to develop new analytical strategies that make it possible to carry out such analyses on seafood, providing a global view of the presence of these analytes, in which species they can be found in the food, and what fraction of them can effectively be absorbed by the human metabolism. With this in mind, this thesis is divided into three chapters. The first study covers the development and evaluation of parameters for the use of microwave-induced combustion combined with ion chromatography coupled with mass spectrometry for the total determination of Br, Cl, F, I, and S in seafood. In the second chapter, the fractionation and influence of culinary treatments for all analytes, as well as the bioavailable fraction of F, Br and I were evaluated. In the third and final chapter, the results regarding F speciation, more specifically the determination of organofluorine compounds, in the studied samples were be presented. It should be noted that these compounds are emerging global contaminants of great relevance, known as "eternal chemicals" due to their stability, persistence, and ability to accumulate in the environment and organisms. They are increasingly present in foods, such as seafood. As the main results obtained, it can be highlighted that, in the first study, a suitable analytical method was developed for halogen and sulfur determination in several types of seafood, using a single chromatographic run. Recoveries ranged from 92% to 109%, considering spiking experiments and certified reference materials analysis. From the second study it was observed that most of Br, I, and F accumulate in shrimp’s shell/head, while most of Cl and S accumulate in shrimp’s muscle tissue, as well as different influences of culinary treatments for these analytes depending on the sample matrix. Also, it was verified that up to 63% of Br can be bioavailable from seafood, while most of I remains on the residual fraction (not bioaccessible/bioavailable). In the final study, a method was developed for F speciation, determining PFAS compounds in seafood. Recoveries for 11 compounds ranged from 83 to 115%. Ten PFAS were detected among all samples and four were quantified. Their concentration was also influenced by culinary treatments. After developing this thesis, it was possible to present, in an unprecedented way, an extremely comprehensive view of the relation between elements so important for human metabolism – halogens and sulfur – and a class of food that are part of the diet of almost all cultures around the world.