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- Assessment of the mechanisms and pathways of fish contamination and mercury-selenium antagonismPublication . Ribeiro, M.; Zephyr, N.; Leufroy, A.; Coelho, I.; Danion, M.; Castanheira, I.; Guerin, T.; Jitaru, P.AIM Mercury (Hg) is one of the most dangerous chemical contaminants for humans and the environment. This is due to its extreme toxicity, particularly in the methylated form, denominated methylmercury (CH3Hg), which is easily absorbed by the body (bioaccumulation). CH3Hg is present in low concentrations in water and in water sediments, and can greatly increase its concentration in aquatic organisms, often reaching more than 85% of total Hg. Therefore, the main source of exposure to CH3Hg is fish consumption, in particular fish from higher trophic levels, since its content tends to increase along the food chain (biomagnification). Nevertheless, it is interesting to note that mercury´s bioavailability seems to be linked to selenium (Se) levels. The Se protective effects against Hg bioaccumulation and toxicity has been identified for the last decades, although the mechanism is still poorly understood. The aim of this study is to accurately assess the Hg-Se interaction in fish and the human dietary exposure. MATERIAL AND METHODS A bioassay was carried out in a representative freshwater fish (rainbow trout) in collaboration with the fish viral pathology unit of ANSES (Ploufragan-Plouzané laboratory). Fish were dietary exposed to CH3Hg under controlled conditions, in the presence or absence of SeMet. The final concentration of CH3Hg and SeMet in the diets was respectively 0,2 μg g-1 and 5 μg g-1. Briefly, six feeding protocols were compared: a non-supplemented diet (control group), a diet supplemented with SeMet, a diet supplemented with MeHg, a diet supplemented with both MeHg and SeMet, a diet supplemented first with MeHg for 1 month and then with SeMet for 2 months and a diet supplemented with SeMet for 1 month and then with MeHg for 2 months. The edible part of fish (muscle) was analysed for SeT and Hgt concentrations by ICP-MS after different time of exposure (1 month, 2 months and 3 months).
- Mackerel seasonality effect on Se contentPublication . Rego, A.; Ventura, M.; Gueifão, S.; Coelho, I.; Cardoso, C.; Afonso, C.; Bandarra, N.; Castanheira, I.Selenium is an essential micronutrient that can become toxic when ingested in high concentrations The human being can obtain Se through the consumption of food, dietary supplements, water and exposure to ambient air The food source is the most abundant and the main contributor to the daily intake of Se in Fish is one of the best sources of Se, and the Portuguese Mackerel is one of the most important and abundant species in Portugal It is rich in several vitamins and Se, due to being a predator The work presented integrates part of the first task of the project Newfood 4 thought that aims at the prevention of cognitive decline through nutrient combination. The aim is to study of the influence of seasonality in the levels of Se in Mackerel samples collected throughout the year. With the exception of May, Se content in mackerel remained constant throughout the year The high Se content found in May samples may be related to mackerel ´ s spawning season and feeding habits However, further studies are needed to confirm these preliminary conclusions, namely studying the Se content monthly for several years
- Building a database for provenance studies of origin wines from the Douro ValleyPublication . Coelho, I.; Matos, A.; Nascimento, A.; Bordado, J.; Donard, O.; Epova, E.; Barre, J.; Berail, S.; Castanheira, I.AIM: The aim of the present work is to produce high quality analytical data suitable for evaluating the provenance of Port wine and Douro wine and integrating an authentic wine reference database. Both wines are produced within the same geographical area, the Douro Valley region located in the northeast of Portugal but follow different vinification procedures. The fermentation of Port wine is interrupted by the addition of a grape based spirit producing a sweet fortified wine typically consumed as digestif and dessert wine. Douro wine, on the other hand, is a table wine. The mineral composition of plants reflects the soil and the environmental conditions under which plants were grown. Minerals and trace elements, as well as some of their isotopes, are potential biomarkers in authenticity studies. We followed two analytical strategies, multielemental analysis and stable isotopes, to understand the parameters common to the region and fundamentally dependent on the soils and the ones influenced by processing methods or environmental contamination. MATERIAL AND METHODS: Fifteen samples of each type of wine, Port and Douro, were characterized for 26 elements. 7Li, 9Be, 11B, 27Al, 52Cr, 55Mn, 59Co, 60Ni, 65Cu, 66Zn, 75As, 77Se, 85Rb, 88Sr, 95Mo, 107Ag, 111Cd, 118Sn, 205Tl, 208Pb were determined by inductively coupled plasma mass spectrometer (ICP-MS) while Fe, Mg , P , Ca , Na , K were analysed by inductively coupled plasma optical emission spectrometer (ICP-OES). In addition, two isotopic systems were also studied: 87Sr/86Sr and 18O determined by Multicollector-ICP-MS (MC-ICP-MS) and Isotope Ratios Mass Spectrometry (IRMS), respectively. For all analysis reagents used were of high purity to prevent for contaminations. Ultra pure water of grade I, as defined in EN ISO 3696, was obtained using a Milli-Q plus Millipore System. Concentrated nitric acid, analytical grade (65%; Merck), was purified in the laboratory, using an acid distillation system (Milestone SubPUR), and compared to a commercial ultrapure nitric acid solution (Merck), on a routine basis. Analytical results were combined with chemometric tools, Principal Components Analysis (PCA) and Hierarchical Cluster Analysis (HCA), capable of performing multivariate data analysis. RESULTS: Ag, Cd and Tl were mostly below the level of quantification and were therefore removed from statistical analysis. 87Sr/86Sr varied between 0,71652 and 0,72290. PCA revealed 6 principal components that explained 84,6% of the total variance. CONCLUSIONS: The vinification method did not affect significantly stable isotopes, either 87Sr/86Sr or 18O. On the other hand, some elements; namely Cr, Co, Cu, Rb, Se, Ca and Na; showed significant differences between the two types of wine. The produced data can be integrated into an authenticity system for Port and Douro wines.
- A method for determination of acrylamide in bread by UPLC-MS/MSPublication . Copeto, Sandra; Jesus, Susana; Motta, Carla; Coelho, Inês; Castanheira, IsabelAcrylamide is a contaminant present especially in baked and fried rich starchy food products, such as french fries, bread, cookies and coffee. It is a product of the Maillard Reaction formed during food processing, at high temperatures by the reaction between free amine groups (amino acids/proteins) and the carbonyl group (sugars/carbohydrates). Acrylamide is classified by the International Agency for Research on Cancer as a carcinogenic substance to humans, and its quantification is essential to control the exposure risk. Since the discovery of its presence in food, several studies have been conducted to developed extraction procedures for acrylamide quantification. The present study aims to develop a cleaning method suitable for several food matrices, like bread and chips, followed by liquid chromatography coupled to a mass detector method (LC-MS/MS) for acrylamide quantification. To achieve this aim, the use of solid-phase extraction and several salts mixtures, such as QuEChERS type, was implemented. The results obtained through the application of mixture 1 (figure 1) were not satisfactory. In this case we observed the tailing effect as well as low recovery of the internal standard, with recovery values below 50%. For the extraction method using mixture 2 (figure 2 and 3) the results were satisfactory, where a spike recovery between 85 to 112% was obtained and the results of the certified reference material varied between 71 and 80 µg/kg, which is within the range of uncertainty. The acrylamide response was linear over a concentration range of 5 to 80 µg/L with a correlation coefficient of the calibration curve above 0.995. The limit of quantification (LOQ) was established at 5 mg/kg. The presented method, LC-MS/MS, with mixture 2 is adequate for the determination of acrylamide in bread , accomplishing the performance criteria of the regulation published by the European Commission, COMMISSION REGULATION (EU) 2017/2158 of 20 November 2017.
- Characterization of food from burnt areas in the Central Region of PortugalPublication . Gueifão, S.; Moreira, T.; Ventura, M.; Delgado, I.; Coelho, I.; Castanheira, I.AIM: Forest fires constitute an environmental problem with adverse and diversified impacts on atmospheric, terrestrial, and aquatic ecosystems, with economic and social repercussions, and a significant impact on flora. Fire mineralizes soil nutrients and returns plant-locked nutrients to the soil. Nutrients are lost from the ecosystem through the release of particulates and volatile compounds during the fire, and later through surface transport and leaching by rains1. Wildfires can play an important role in the environmental distribution of major and trace elements, including through their mobilization by fire-induced runoff and associated transport of soil and ash particles. Also, wildfires have been found to release and deposit contaminants on the soil surface, either directly by combustion of vegetation and mineralization of soil organic matter or indirectly through interactions of ashes. This fact can lead to the addition of potentially significant amounts of these elements in the soil and, thereby, can alter its chemical properties2. This study aims to evaluate the content of arsenic (As), cadmium (Cd) and chromium (Cr) in cabbage, potatoes, eggs and fruit samples cultivated in recently burnt areas. MATERIAL AND METHODS: A total of 24 pools composed of 3 samples each was analysed at three different harvest periods. Cabbage samples from burnt zones were compared with a designated control sample from a non-burnt zone. Analytical determinations were performed by Inductive Plasma Coupled Mass Spectrometry (ICP-MS). Previously, samples underwent a heating block acid digestion with a validated time and temperature program. Speciation analysis was carried out by High Performance Liquid Chromatography (HPLC) coupled to ICP-MS. Before analysis, samples were extracted using nitric acid. Analyses were performed in accordance with ISO 17025:2005. RESULTS: The concentrations of As in fruits and Cd in eggs were below the limit of quantification (2.2 µg/kg and 3.1 µg/kg, respectively). The variation of Cr content between matrices was as follows: fruits > eggs > cabbages > potatoes. On the other hand, As contents was verified as: cabbage > eggs > potatoes > fruit. Cabbage presented the highest Cd content, while eggs had the lowest values for this element. When compared to the control sample, the most pronounced rise was observed for As. Speciation studies show that the predominant arsenic species in cabbages are also the most toxic ones, that is, arsenite (As (III)) and arsenate (As (V)). CONCLUSIONS: The values of the inorganic elements present in this study are not yet properly legislated so it is important to performed studies able to support future legal references. Monitoring studies based on accredited methods are a powerful aid in assessing the risk exposure of affected populations.
- Policies and strategies in food and healthy lifestylesPublication . Jesus, s.; Coelho, M.; Dias, G.; Castanheira, I.AIM: The rapid growth in industrialisation, urbanisation and market globalisation had a significant impact on population diets and lifestyles. At the same time, the living standards improved, the food availability expanded and became more diversified. However, it occurred an increase in dietary patterns and physical inactivity, which led to a rise in the chronic non-communicable diseases(NCDs), including obesity, diabetes, cardiovascular disease, hypertension, stroke and cancer. It was determined that in 2001 chronic burden diseases contributed 46% in the world and that in 2020 will increase to 57%. So, the present study aimed to analyse the strategies and policies in health and food lifestyles in Europe. The study was developed in the project “A Quadruple Helix Atlantic Area Healthy Food Ecosystem for Growth of SME’s”(AHFES). This project aims to improve the competitiveness and growth of SMEs in the value chain of healthy eating and lifestyles, contributing to the development of a transnational innovation ecosystem that helps entities to access information, partners and markets and align their products and services to the needs and expectations of the European consumer/community. MATERIAL AND METHODS: In the present study was used different approaches and tools. It was made a literature review with the terms of “healthy food policies”, “healthy lifestyles policies” and “food policy”. Another approach was the information collected from the partners about the existing regional policies and strategies in healthy food, where it was made some questions about healthy food and lifestyles and innovation policies, innovation tools and existing support structures and reforms in each country (Portugal, Spain, Ireland, France and the United Kingdom). RESULTS: The countries increasing the policies and measures to be implemented in the area of health. It was found that although most countries have very similar national plans, their policies and levels of implementation vary between them. In general, the implemented measures and policies are organized into two groups: health and lifestyles programmes and policies and support structures and reforms. These groups have high relevance in changing dietary patterns and lifestyles. Besides, in most countries, there was a consensus on the most important and priority age groups for a more effective outcome of measures and policies in the future. These two age groups were children, who are still open to new knowledge and knowledge in the area of food, and the elderly who corresponds to a group that requires the effects of NCD risk factors to be controlled. The measures and policies applied to increase and encourage society to modify its diet and lifestyle were diverse and can be grouped into five groups: nutrition and diet counselling, portion size control, regulation of marketing to children, reformulation and dietary guidelines. CONCLUSIONS: To improve healthy food and lifestyles of the population, it is necessary to regularly re-evaluate strategies and consequent effects on the health status of the community. Besides, to the implementation of strategies and policies to be successful, there must be cooperation between the government-university-industry and community. AFHES project is an important tool to assist SME in the production of foods framed by new health guidelines.