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Sixteen multiparous Holstein cows in four blocks of 4 × 4 Latin square over 4-week experimental periods were used to study the effects of seaweed (Saccharina latissima) supplement (with/without) and protein source (rapeseed meal (RSM)/wheat distiller's grain (WDG)) on milk mineral concentrations. Dietary treatments did not affect milk production and basic composition. Feeding seaweed slightly decreased milk Ca and Cu concentrations; whilst increased (by 3.3-fold) milk iodine (I) concentration, due to a higher dietary I supply. Substitution of WDG with RSM increased feed-to-milk transfer of Ca, Na, and Se and decreased that of Mg, P, Fe, and Mn; but only reduced milk Mn and I concentrations (the latter by 27 % as a potential result of increased glucosinolate intake). Seaweed supplement can improve milk I content when cows' I supply/availability is limited, but care should be taken to avoid excess milk I contents that may pose nutritional risks for young children.
Assuntos
Brassica napus , Brassica rapa , Phaeophyceae , Alga Marinha , Feminino , Bovinos , Animais , Leite/metabolismo , Lactação , Ração Animal/análise , Dieta/veterinária , Suplementos Nutricionais , Grão Comestível , Verduras , Minerais/metabolismoRESUMO
This study aimed to investigate the effects of two brown Icelandic seaweed samples (Ascophyllum nodosum and Fucus vesiculosus) on in vitro methane production, nutrient degradation, and microbiota composition. A total mixed ration (TMR) was incubated alone as control or together with each seaweed at two inclusion levels (2.5 and 5.0% on a dry matter basis) in a long-term rumen simulation technique (Rusitec) experiment. The incubation period lasted 14 days, with 7 days of adaptation and sampling. The methane concentration of total gas produced was decreased at the 5% inclusion level of A. nodosum and F. vesiculosus by 8.9 and 3.6%, respectively (P < 0.001). The total gas production was reduced by all seaweeds, with a greater reduction for the 5% seaweed inclusion level (P < 0.001). Feed nutrient degradation and the production of volatile fatty acids and ammonia in the effluent were also reduced, mostly with a bigger effect for the 5% inclusion level of both seaweeds, indicating a reduced overall fermentation (all P ≤ 0.001). Microbiota composition was analyzed by sequencing 16S rRNA amplicons from the rumen content of the donor cows, fermenter liquid and effluent at days 7 and 13, and feed residues at day 13. Relative abundances of the most abundant methanogens varied between the rumen fluid used for the start of incubation and the samples taken at day 7, as well as between days 7 and 13 in both fermenter liquid and effluent (P < 0.05). According to the differential abundance analysis with q2-ALDEx2, in effluent and fermenter liquid samples, archaeal and bacterial amplicon sequence variants were separated into two groups (P < 0.05). One was more abundant in samples taken from the treatment without seaweed supplementation, while the other one prevailed in seaweed supplemented treatments. This group also showed a dose-dependent response to seaweed inclusion, with a greater number of differentially abundant members between a 5% inclusion level and unsupplemented samples than between a 2.5% inclusion level and TMR. Although supplementation of both seaweeds at a 5% inclusion level decreased methane concentration in the total gas due to the high iodine content in the seaweeds tested, the application of practical feeding should be done with caution.
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Thirty conventional and twenty-four organic dairy farms were divided into equal numbers within system groups: high-pasture, standard-pasture, and low-pasture groups. Milk samples were collected monthly for 12 consecutive months. Milk from high-pasture organic farms contained less fat and protein than standard- and low-pasture organic farms, but more lactose than low-pasture organic farms. Grazing, concentrate feed intake and the contribution of non-Holstein breeds were the key drivers for these changes. Milk Ca and P concentrations were lower in standard-pasture conventional farms than the other conventional groups. Milk from low-pasture organic farms contained less Ca than high- and standard-pasture organic farms, while high-pasture organic farms produced milk with the highest Sn concentration. Differences in mineral concentrations were driven by the contribution of non-Holstein breeds, feeding practices, and grazing activity; but due to their relatively low numerical differences between groups, the subsequent impact on consumers' dietary mineral intakes would be minor.
RESUMO
To study the effects of dairy production system on milk macromineral and trace element concentrations, milk samples were collected monthly in 2019 from 43 conventional and 27 organic farms. Organic milk contained more Ca (1049.5 vs. 995.8 mg/kg), K (1383.6 vs. 1362.4 mg/kg), P (806.5 vs. 792.5 mg/kg) and Mo (73.3 vs. 60.6 µg/kg) but less Cu (52.4 vs. 60.6 µg/kg), Fe (0.66 vs 2.03 mg/kg), Mn (28.8 vs. 45.0 µg/kg), Zn (4.51 vs. 5.00 mg/kg) and Al (0.32 vs. 1.14 µg/kg) than conventional milk. Significant seasonal variation was observed in all determined minerals' concentrations. Milk I concentration was not consistently affected by production system, whereas organic milk contained less I in June and July than conventional milk. Dietary factors contributing to different milk mineral concentrations between production systems included intakes of maize silage, dry-straights and oils (higher in conventional diets), and pasture, clover and wholecrop (higher in organic diets).
Assuntos
Leite/química , Agricultura Orgânica , Oligoelementos/análise , Animais , Cálcio/análise , Dieta/veterinária , Feminino , Ferro/análise , Potássio/análise , Estações do Ano , Silagem , Trifolium , Zea maysRESUMO
Brown macroalgae Saccharina latissima (30-40 individuals) and Alaria esculenta (15-20 individuals) were collected from natural populations in winter in Iceland. The algal thalli were sectioned into different parts (e.g. holdfast, stipe, old frond, young frond and sori-containing frond sections) that differed in age and biological function. The work elucidated that arsenic (As) was not uniformly distributed within the two brown macroalgal species, with lower levels of total As were found in the stipe/midrib compared to other thallus parts. The arsenosugars mirrored the total arsenic in the seaweed mainly due to AsSugSO3 being the most abundant As species. However, arsenic speciation using parallel HPLC-ICP-MS/ESI-MS elucidated that the arsenic-containing lipids (AsL) had a different distribution where the arsenosugarphospholipids (AsPL) differed by approximately a factor of 4 between the sections containing the lowest and highest concentrations of AsPLs. When placing the sections in order of metabolic activity and an estimate of tissue age, there appeared to be a relationship between the activity and AsPLs, with lower levels of AsPLs in oldest parts. This is the first time such a relationship has been shown for AsLs. Hence, by applying sophisticated analytical techniques, it was possible to gain a deeper understanding of arsenolipids in seaweed.
Assuntos
Arsênio/metabolismo , Metabolismo dos Lipídeos , Phaeophyceae/metabolismo , Alga Marinha/metabolismo , Cromatografia Líquida de Alta Pressão/métodos , Limite de Detecção , Phaeophyceae/classificação , Plantas Comestíveis/metabolismo , Controle de Qualidade , Especificidade da Espécie , Espectrometria de Massas por Ionização por Electrospray/métodosRESUMO
More than 1000 time-series of persistent organic pollutants (POPs) in Arctic biota from marine and freshwater ecosystems some extending back to the beginning of 1980s were analyzed using a robust statistical method. The Arctic area encompassed extended from Alaska, USA in the west to northern Scandinavian in the east, with data gaps for Arctic Russia and Arctic Finland. The aim was to investigate whether temporal trends for different animal groups and matrices were consistent across a larger geographical area. In general, legacy POPs showed decreasing concentrations over the last two to three decades, which were most pronounced for α-HCH and least pronounced for HCB and ß-HCH. Few time-series of legacy POPs showed increasing trends and only at sites suspected to be influenced by local source. The brominated flame retardant congener BDE-47 showed a typical trend of increasing concentration up to approximately the mid-2000s followed by a decreasing concentration. A similar trend was found for perfluorooctane sulfonic acid (PFOS). These trends are likely related to the relatively recent introduction of national and international controls of hexa- and hepta-BDE congeners and the voluntary phase-out of PFOS production in the USA in 2000. Hexabromocyclododecane (HBCDD) was the only compound in this study showing a consistent increasing trend. Only 12% of the long-term time-series were able to detect a 5% annual change with a statistical power of 80% at αâ¯<â¯0.05. The remaining 88% of time-series need additional years of data collection before fulfilling these statistical requirements. In the case of the organochlorine long-term time-series, 45% of these would require >20â¯years monitoring before this requirement would be fulfilled.
Assuntos
Charadriiformes/metabolismo , Exposição Ambiental , Peixes/metabolismo , Mamíferos/metabolismo , Poluentes Químicos da Água/metabolismo , Animais , Regiões Árticas , Monitoramento Ambiental , Água Doce , Mytilus edulis/metabolismo , Oceanos e Mares , Estações do Ano , Fatores de TempoRESUMO
A Quality Management Framework to improve quality and harmonization of Total Diet Study practices in Europe was developed within the TDS-Exposure Project. Seventeen processes were identified and hazards, Critical Control Points and associated preventive and corrective measures described. The Total Diet Study process was summarized in a flowchart divided into planning and practical (sample collection, preparation and analysis; risk assessment analysis and publication) phases. Standard Operating Procedures were developed and implemented in pilot studies in five organizations. The flowchart was used to develop a quality framework for Total Diet Studies that could be included in formal quality management systems. Pilot studies operated by four project partners were visited by project assessors who reviewed implementation of the proposed framework and identified areas that could be improved. The quality framework developed can be the starting point for any Total Diet Study centre and can be used within existing formal quality management approaches.
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Dieta , Europa (Continente) , Humanos , Projetos Piloto , Medição de RiscoRESUMO
A total diet study (TDS) is a public health tool for determination of population dietary exposure to chemicals across the entire diet. TDSs have been performed in several countries but the comparability of data produced is limited. Harmonisation of the TDS methodology is therefore desirable and the development of comparable TDS food lists is considered essential to achieve the consistency between countries. The aim of this study is to develop and test the feasibility of a method for establishing harmonised TDS food and sample lists in five European countries with different consumption patterns (Czech Republic, Finland, Germany, Iceland and Portugal). The food lists were intended to be applicable for exposure assessment of wide range of chemical substances in adults (18-64 years) and the elderly (65-74 years). Food consumption data from recent dietary surveys measured on individuals served as the basis for this work. Since the national data from these five countries were not comparable, all foods were linked to the EFSA FoodEx2 classification and description system. The selection of foods for TDS was based on the weight of food consumed and was carried out separately for each FoodEx2 level 1 food group. Individual food approach was respected as much as possible when the TDS samples were defined. TDS food lists developed with this approach represented 94.7-98.7% of the national total diet weights. The overall number of TDS samples varied from 128 in Finland to 246 in Germany. The suggested method was successfully implemented in all five countries. Mapping of data to the EFSA FoodEx2 coding system was recognised as a crucial step in harmonisation of the developed TDS food lists.
Assuntos
Inquéritos sobre Dietas , Dieta , Exposição Ambiental , Inocuidade dos Alimentos , Alimentos , Adolescente , Adulto , Idoso , República Tcheca , Registros de Dieta , Europa (Continente) , Feminino , Finlândia , Contaminação de Alimentos/análise , Alemanha , Humanos , Islândia , Masculino , Pessoa de Meia-Idade , Portugal , Medição de RiscoRESUMO
As the ice cap of the Arctic diminishes due to global warming, the polar sailing route will be open larger parts of the year. These changes are likely to increase the pollution load on the pristine Arctic due to large vessel traffic from specific contaminant groups, such as polycyclic aromatic hydrocarbons (PAHs). A well-documented baseline for PAH concentrations in the biota in the remote regions of the Nordic Seas and the sub-Arctic is currently limited, but will be vital in order to assess future changes in PAH contamination in the region. Blue mussels (Mytilus edulis) were collected from remote sites in Greenland, Iceland, the Faroe Islands, Norway and Sweden as well as from urban sites in the same countries for comparison. Cod (Gadus morhua) was caught north of Iceland and along the Norwegian coast. Sixteen priority PAH congeners and the inorganic trace elements arsenic, cadmium, mercury and lead were analysed in the blue mussel samples as well as PAH metabolites in cod bile. Σ16PAHs ranged from 28 ng/g dry weight (d.w.) (Álftafjörður, NW Iceland) to 480 ng/g d.w. (Ísafjörður, NW Iceland). Mussel samples from Mjóifjörður, East Iceland and Maarmorilik, West Greenland, contained elevated levels of Σ16PAHs, 370 and 280 ng/g d.w., respectively. Levels of inorganic trace elements varied with highest levels of arsenic in mussels from Ísafjörður, Iceland (79 ng/g d.w.), cadmium in mussels from Mjóifjörður, Iceland (4.3 ng/g d.w.), mercury in mussels from Sørenfjorden, Norway (0.23 ng/g d.w.) and lead in mussels from Maarmorilik, Greenland (21 ng/g d.w.). 1-OH-pyrene was only found above limits of quantification (0.5 ng/mL) in samples from the Norwegian coast, ranging between 44 and 140 ng/ml bile. Generally, PAH levels were low in mussels from the remote sites investigated in the study, which indicates limited current effect on the environment.
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Monitoramento Ambiental , Hidrocarbonetos Policíclicos Aromáticos/análise , Oligoelementos/análise , Poluentes Químicos da Água/análise , Animais , Regiões Árticas , Dinamarca , IslândiaRESUMO
Perfluorinatedalkyl acids (PFAAs) are of growing concern due to possible health effects on humans. Exposure assessments indicate that fish consumption is one of the major sources of perfluorooctane sulfonate (PFOS) exposure to humans, one of the major PFASs, whereas concerns of overestimation of this exposure source have been raised. Therefore, PFAAs concentrations in fish from the North Atlantic (Icelandic fishing grounds) in the flesh of different fish species were investigated along with more detailed analyses of tissue concentrations in cod (Gadus morhua) and lumpfish (Cyclopterus lumpus). Further, fish feed was investigated as a possible source of PFAAs in aquaculture by examining fish meal as feed ingredient. No PFAAs were detected in the edible part of all fish samples, except for PFOS in pollock (Pollachius virens, 0,05 ng/g wet weight). PFOS was the only PFAA detected in the fish meal samples with the exception of PFOSA in blue whiting (Micromesistius poutassou) meal (0,45 ng/g dry weight (d.w.)), where the PFOS concentration was 1,3-13 ng/g d.w. in the capelin (Mallotus villosus) and mackerel (Scomber scombrus) meal samples. The conclusions of the study are that fish commonly consumed from the Icelandic fishing grounds are unlikely to be an important source of PFAAs exposure.
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Monitoramento Ambiental , Peixes/metabolismo , Fluorocarbonos/análise , Alimentos Marinhos/análise , Poluentes Químicos da Água/análise , Animais , Cromatografia Líquida , Produtos Pesqueiros/análise , Fluorocarbonos/metabolismo , Islândia , Espectrometria de Massas em Tandem , Poluentes Químicos da Água/metabolismoRESUMO
Contaminants have been analyzed in cod (Gadus morhua) since 1990 as part of the national monitoring program for the environmental conditions in the sea around Iceland. The aim of this study was to determine the temporal trends of persistent organic pollutants (POPs: polychlorinated biphenyls (PCBs), p,p'-dichlorodiphenyl dichloroethene (p,p'-DDE), hexachlorobenzene (HCB), hexachlorocyclohexanes (HCHs), chlordanes (CHLs) and toxaphenes (Tox)) and trace elements (As, Cd, Cu, Hg, Pb, Se and Zn) in cod over the last two decades at two different locations in the Arctic Ocean north of Iceland. The relationship between the contaminant concentrations and biological covariates was also determined. All of the POPs showed decreasing trends but the trace elements showed no clear signs of trend except arsenic which showed an increasing trend and zinc which showed a decreasing trend. The concentration of the POPs were lower or similar in the Icelandic cod compared to cod sampled in Norway, the Barents Sea and in the Baltic Sea, except for HCB which was higher in the Icelandic cod compared to the Norwegian cod. The concentration of the trace elements As, Cu, Hg and Zn were similar in the Icelandic cod compared to cod sampled in Norway and Greenland but the concentration of Cd was higher in the Icelandic cod. The inclusion of the biological covariates was found to be important for the statistical analysis. The POPs had a positive relationship with liver fat content but negative relationship with liver weight. The trace elements had a negative relationship with liver fat and liver weight except As which had positive relationship with liver weight. Only positive relationships were observed between the contaminant concentrations and length.
Assuntos
Monitoramento Ambiental , Gadus morhua/metabolismo , Poluentes Químicos da Água/metabolismo , Poluição Química da Água/estatística & dados numéricos , Animais , Diclorodifenil Dicloroetileno/metabolismo , Islândia , Praguicidas/metabolismo , Bifenilos Policlorados/metabolismo , Oligoelementos/metabolismoRESUMO
Nine different extraction methods were evaluated for three seafood samples to test whether the concentration of inorganic arsenic (iAs) determined in seafood is dependent on the extraction method. Certified reference materials (CRM) DOLT-4 (Dogfish Liver) and TORT-2 (Lobster Hepatopancreas), and a commercial herring fish meal were evaluated. All experimental work described here was carried out by the same operator using the same instrumentation, thus eliminating possible differences in results caused by laboratory related factors. Low concentrations of iAs were found in CRM DOLT-4 (0.012±0.003mgkg(-1)) and the herring fish meal sample (0.007±0.002mgkg(-1)) for all extraction methods. When comparing the concentration of iAs in CRM TORT-2 found in this study and in the literature dilute acids, HNO3 and HCl, showed the highest extracted iAs wheras dilute NaOH (in 50% ethanol) showed significantly lower extracted iAs. However, most other extraction solvents were not statistically different from one another.
Assuntos
Arsênio/análise , Arsênio/isolamento & purificação , Fracionamento Químico/métodos , Contaminação de Alimentos/análise , Alimentos Marinhos/análise , AnimaisRESUMO
Because of the toxicity of inorganic arsenic (iAs), only iAs needs to be monitored in food and feedstuff. This demands the development of easy and quick analytical methods to screen large number of samples. This work focuses on hydride generation (HG) coupled with an ICPMS as an arsenic detector where the HG is added as a selective step to determine iAs in the gaseous phase while organically bound As remains in the solution. iAs forms volatile arsine species with high efficiency when treated with NaBH4 at acidic conditions, whereas most other organoarsenic compounds do not form any or only less volatile arsines. Additionally, using high concentrations of HCl further reduces the production of the less volatile arsines and iAs is almost exclusively formed, therefore enabling to measure iAs without a prior step of species separation using chromatography. Here, we coupled a commercially available HG system to an ICPMS and optimized for determination of iAs in rice and samples of marine origin using different acid concentrations, wet and dry plasma conditions, and different reaction gas modes. Comparing this method to conventional HPLC-ICPMS, no statistical difference in iAs concentration was found and comparable limits of detections were achieved using less than half the instrument time.
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The identification of molecular structures of an arsenolipid is pivotal for its toxicological assessment and in understanding the arsenic cycling in the environment. However, the analysis of these compounds in a lipid matrix is an ongoing challenge. So far, only a few arsenolipids have been reported, including arsenic fatty acids (AsFAs) and arsenic hydrocarbons (AsHCs). By means of RP-HPLC-ICPMS/ESMS, we investigated Capelin oil ( Mallotus villosus ) for possible new species of arsenolipids. Twelve arsenolipids were identified in the fish oil including three AsFAs and seven AsHCs. Among the AsHCs, four that were identified had protonotated molecular masses of 305, 331, 347, and 359 and have not been reported before. In addition, the compounds with molecular formulas C20H44AsO(+) and C24H44AsO(+) were found in low concentrations and showed chromatographic properties and MS data consistent with cationic trimethylarsenio fatty alcohols. Derivatization by acetylation and thiolation coupled with accurate mass spectrometry was successfully used to establish the occurrence of this new class of arsenolipids as cationic trimethylarsenio fatty alcohols (TMAsFOH).
Assuntos
Arsênio/análise , Óleos de Peixe/química , Lipídeos/análise , Animais , Cromatografia Líquida de Alta Pressão , Peixes , Espectrometria de Massas , Estrutura MolecularRESUMO
Contaminants have been determined in blue mussels (Mytilus edulis) at 11 locations around the Icelandic coastline from 1990 to 2010. The aim of the present study was to investigate if there has been a change in concentration of contaminants around the Icelandic coastline for the last two decades and if the concentrations and changes, if present, were consistent between locations. Concentrations of the persistent organic pollutants, p,p'-dichlorodiphenyldichloroethene (p,p'-DDE), hexachlorobenzene (HCB), α-hexachlorocyclohexane (α-HCH), polychlorinated biphenyl (PCB-153) and trans-nonachlor, have decreased at most of the sampling locations in Iceland in recent years. However, an increasing trend was found at a few locations that could be explained by anthropogenic activity. The concentration levels of the persistent organics were much lower than found at the Norwegian, USA and Chinese coasts, especially levels of p,p'-DDE. The concentration of copper and selenium had a consistent pattern of change and concentration between locations over the period which showed a decreasing trend in recent years. The trace elements arsenic, cadmium, mercury and zinc showed more variation in concentration between locations, the concentration of arsenic, mercury and zinc was fairly stable over the period, whereas there were fluctuations in cadmium concentrations. The concentrations of cadmium and zinc were observed to be somewhat higher than found in mussels from Norway, USA and China but values of mercury and lead were much lower in the mussel sampled in Iceland. The higher concentrations of cadmium and zinc can be explained by the volcanic activity in Iceland but no major anthropogenic sources of trace elements are known in Iceland.
Assuntos
Bivalves/metabolismo , Exposição Ambiental , Hidrocarbonetos Clorados/metabolismo , Oligoelementos/metabolismo , Poluentes Químicos da Água/metabolismo , Animais , Cromatografia Gasosa , Monitoramento Ambiental , Islândia , Espectrometria de Massas , Estações do Ano , Espectrofotometria AtômicaRESUMO
This paper describes a quantitative risk-benefit assessment of fish consumption. We compare the net health effect expressed in DALYs of two scenarios. The reference scenario is the current fish intake of the Dutch population, which is less than what is recommended by the health authorities. The alternative scenario describes the health effects if the population consumes 200g of fish per week, which is close to the recommendation. All health effects due to fish consumption for which there is convincing evidence are incorporated in the assessment. The QALIBRA software (www.qalibra.eu) is used to simulate the two scenarios. The results show there is a net benefit for the population if it consumes 200g of fish each week.
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Contaminação de Alimentos , Medição de Risco , Alimentos Marinhos , Doença das Coronárias/etiologia , Feminino , Humanos , Masculino , Países Baixos , Contagem de Espermatozoides , Acidente Vascular Cerebral/etiologia , Hormônios Tireóideos/sangueRESUMO
The fish ingredient N3-docosahexaenoic acid 22:6 n-3 (DHA) stimulates brain development. On the other hand methylmercury (MeHg) in fish disturbs the developing central nervous system. In this Context the IQ score in children is considered as an aggregate measure of in utero brain development. To determine the effect of DHA exposure on prenatal neurodevelopment the maternal DHA intake during pregnancy was compared with its epidemiologically observed effect on the IQ score of children. For MeHg the maternal intake was converted into its accumulation in the maternal body. The maternal body burden then was compared with its epidemiologically observed relationship with the IQ score. Taking the MeHg and DHA content of 33 fish species the net effect of these compounds on the IQ score was quantified. For most fish species the adverse effect of MeHg on the IQ score exceeded the beneficial effect of DHA. In the case of long-living predators a negative effect up to 10 points on the IQ score was found. The results of this study indicate that food interventions aiming at the beneficial effects of fish consumption should focus on fish species with a high DHA content, while avoiding fish species with a high MeHg content.
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Sistema Nervoso Central/embriologia , Exposição Materna , Medição de Risco , Alimentos Marinhos , Adulto , Carga Corporal (Radioterapia) , Criança , Ácidos Docosa-Hexaenoicos/administração & dosagem , Feminino , Humanos , Compostos de Metilmercúrio/farmacocinética , Compostos de Metilmercúrio/toxicidade , Gravidez , Efeitos Tardios da Exposição Pré-NatalRESUMO
The EU project BRAFO proposed a framework for risk-benefit assessment of foods, or changes in diet, that present both potential risks and potential benefits to consumers (Hoekstra et al., 2012a). In higher tiers of the BRAFO framework, risks and benefits are integrated quantitatively to estimate net health impact measured in DALYs or QALYs (disability- or quality-adjusted life years). This paper describes a general model that was developed by a second EU project, Qalibra, to assist users in conducting these assessments. Its flexible design makes it applicable to a wide range of dietary questions involving different nutrients, contaminants and health effects. Account can be taken of variation between consumers in their diets and also other characteristics relevant to the estimation of risk and benefit, such as body weight, gender and age. Uncertainty in any input parameter may be quantified probabilistically, using probability distributions, or deterministically by repeating the assessment with alternative assumptions. Uncertainties that are not quantified should be evaluated qualitatively. Outputs produced by the model are illustrated using results from a simple assessment of fish consumption. More detailed case studies on oily fish and phytosterols are presented in companion papers. The model can be accessed as web-based software at www.qalibra.eu.
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Alimentos , Modelos Teóricos , Medição de Risco , Incerteza , União EuropeiaRESUMO
BACKGROUND/OBJECTIVES: Significant changes have been reported in dietary habits and food availability in Iceland that would be expected to compromise selenium intake and status, especially among young people. These include substantial decreases in the consumption of fish and milk, as well as the selenium content of imported wheat. The aim of this study was to assess selenium in the diet and whole blood of adolescent girls, as well as define the most important foods contributing to intake and blood concentrations of selenium. DESIGN: The subjects were 96 randomly selected girls, aged 16-20, who answered a validated food frequency questionnaire (FFQ) for dietary assessment. Selenium intake from each food group was calculated in µg/day. Blood samples were collected for measurement of whole blood selenium. RESULTS: Mean dietary selenium was 51±25 µg/day. Milk/dairy products, including cheese, contributed 36±14% of total dietary selenium; fish 18±12%; and bread/cereal products 13±6%. Mean whole blood selenium was 117±12 µg/l (range 90-208); nearly 90% of subjects were above the optimal level of 100 µg/l. Fish and bread/cereal products were the only foods significantly correlated with selenium in blood (r=0.32; P=0.002 and r=0.22; P=0.04, respectively) while no correlation was found with milk and dairy products in spite of their greater contribution to total selenium intake. CONCLUSION: In this population of Icelandic adolescent girls, selenium intake and status seem acceptable. Judging from associations between intake and blood levels, fish and cereals may be the most important contributors to blood selenium.