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- WHO reference protocol for measuring fatty acids in foods, with emphasis on monitoring trans-fatty acids originating from partial hydrogenation of edible oilsPublication . World Health Organization Nutrition and Food Safety (NFS)Executive summary: In December 2020, the World Health Organization (WHO) first developed and published a laboratory protocol for measuring trans-fatty acids (TFAs) in foods2 (hereinafter referred to as the “WHO reference protocol”). Although the WHO reference protocol was successfully implemented in several laboratories worldwide, some laboratories, especially those operating with a limited budget, had challenges implementing it. These laboratories requested that the procedures be simplified, and suitable alternative methods and chemicals be included in the protocol so that it is easier to use and globally applicable. In response to the requests, WHO organized an expert consultation meeting in June 2022, based on which the Simplified Protocol for Measuring TFA content (hereinafter referred to as the “WHO simplified protocol”) was developed.3 This fit-for purpose protocol can be implemented by all laboratories including those with limited budgets, and provides most of the data that are required for governments’ surveillance and monitoring activities to check the trend of TFA content of fats and oils added during food preparation and processing. This will ensure that the fats and oils used in preparation comply with regulations for TFA elimination. Regarding the key differences between the original WHO reference protocol and the WHO simplified protocol, please refer to Table 1 in the report of the WHO expert consultation held in June 2022. When developing the WHO simplified protocol, new data and information were obtained on the procedures for measuring fatty acids (FA). It was realized that the WHO reference protocol needs to be revised to provide up-to-date, comprehensive and validated options for conducting full fatty acid methyl ester (FAME) analysis. A 2-day, virtual WHO Expert Consultation was held on 19 and 22 September 2023 to update the WHO reference protocol.5 In doing so, all the critical steps of the WHO reference protocol and the WHO simplified protocol were reviewed. During this expert consultation, validated alternative procedures were recommended for increasing the versatility of the protocol and expanding its ability to analyse all types of food products that could contain TFAs. This revised document, entitled “WHO laboratory protocol – Reference protocol for measuring fatty acids in foods, with emphasis on monitoring trans-fatty acids originating from partial hydrogenation of edible oils” comprehensively includes validated procedures for fat extraction, gas chromatography (GC) peak identification, and determination of FAME flame ionization detector response. It also includes validated alternatives for internal standards, methylating agents, solvents for preparing FAMEs, GC parameters for determination of FA composition, and FAME reference standards. Furthermore, this protocol includes two sample preparation procedures in which the FA are methylated directly in the food sample before extraction, significantly reducing the time and cost of analysis. Throughout this document “methylation” is defined as the generic process of converting FA to FAME regardless of their free or bound status. The described procedures allow the determination of the TFA content as grams (g) per 100 g of food, grams per 100 g total FAs and grams per 100 g total fat. For measuring TFA in grams of FA per 100 g of food, an internal standard should be added to the test food sample portion before fat extraction or combined methylation/extraction. For the differences among the original WHO reference protocol, the WHO simplified protocol and the updated WHO reference protocol, please refer to Table 1 of this document. The updated WHO reference protocol retains the following sections outlined in the 2020 WHO reference protocol and 2022 WHO simplified protocol: clinical relevance, dietary trans fats, sampling plan, sample collection and storage, sample preparation for analysis, safety precautions and laboratory equipment. This updated WHO reference protocol replaces the original WHO global reference protocol. This updated edition of the WHO reference protocol is a compendium of validated procedures for conducting FAME analysis, allowing laboratories to choose the most suitable procedure for their specific analytical needs. While this protocol is also inclusive of all the procedures outlined in the WHO simplified protocol (except for the fat extraction procedure using solvents in section 6.3.2), the simplified protocol will remain as a standalone protocol as it is a useful summary of the fit-for-purpose procedures, and is recommended for laboratories operating on a limited budget and which are aiming to obtain the minimal data required for government surveillance and monitoring activities of fats and oils externally added during food preparation and processing.
- Food contaminants and human health: challenges in chemical mixturesPublication . Alvito, Paula; Assunção, Ricardo; Louro, Henriqueta; Silva, Maria João; Vasco, ElsaThis book compiles the extended abstracts from some of the world-renowned researchers invited to give a lecture at the ICFC2015, in addition to the abstracts from oral and poster sessions.
- Alterações do Estado de Saúde Associadas à Alimentação: Contaminação Química - MicotoxinasPublication . Alvito, Paula; Oliveira, Luisa; Calhau, Maria Antónia; Dias, Carlos MatiasCom este pequeno apontamento sobre micotoxinas pretende-se contribuir para divulgar o conhecimento técnico e científico disponível sobre a ocorrência destes contaminantes químicos nos alimentos e sobre as alterações do estado de saúde associadas à sua presença nos mesmos. A bibliografia existente neste domínio encontra-se geralmente disponível em língua inglesa pelo que se justifica este pequeno apontamento em português de fácil acesso a profissionais de saúde, investigadores, estudantes universitários e público em geral. Neste documento incluem-se seis secções cujo objetivo consiste em abordar as questões atuais consideradas mais relevantes no domínio das micotoxinas e suas implicações na saúde humana. Na primeira secção é efetuada uma introdução geral sobre as micotoxinas assim como uma referência a importantes desafios futuros no domínio da micotoxicologia. Na segunda, referem-se as características dos principais grupos de micotoxinas e sintetizam-se os resultados de estudos desenvolvidos em Portugal. Na terceira, referem-se as vias de exposição a estas toxinas naturais assim como os seus biomarcadores detetados nos fluidos biológicos (sangue, urina). Na quarta, descrevem-se os quadros clínicos e a abordagem diagnóstica das micotoxicoses (agudas e crónicas) focando, em particular, os efeitos na saúde das crianças. Nas secções cinco e seis referem-se, respetivamente, os aspetos regulamentares e métodos analíticos de determinação de micotoxinas e os efeitos das alterações climáticas no desenvolvimento de espécies de fungos toxigénicos e na produção de micotoxinas. Para além da divulgação dos conhecimentos científicos, a autora pretende alertar o leitor para a importância do tema e para o impacte que a exposição humana a micotoxinas e as alterações do estado de saúde associadas poderão vir a atingir num futuro próximo, em particular, no que se refere às populações mais vulneráveis como as crianças e os grupos sociais mais pobres. A autora inclui também, ao longo do texto, algumas considerações sobre lacunas de conhecimento nos diferentes domínios abordados salientando, por fim, o importante papel que os profissionais de saúde, investigadores, universitários, e público em geral, poderão desempenhar na vigilância e proteção da saúde pública.