Challenges and opportunities when moving food production and consumption toward sustainable diets in the Nordics: a scoping review for Nordic Nutrition Recommendations 2023.

The terms 'Nordic countries' or 'The Nordics' include the five countries Denmark, Finland, Island, Norway, and Sweden. This review includes evaluation of the Nordic countries against Food and Agricultural Organisation (FAO)/World Health Organizations' (WHO) guiding principles for healthy, sustainable diets with respect to environmental impact (principles #9 - #13) and sociocultural aspects (principles #14 - #16). A food systems perspective is taken to summarize and discuss the most important challenges and opportunities for achieving sustainable diets. Food system, food security, self-sufficiency, and resilience perspectives are applied. The information can underpin decisions when developing and implementing Food Based Dietary Guidelines (FBDG) in the Nordics. None of the Nordic countries are on track to reach the 2030 UN climate and biodiversity goals. We describe how food production, processing, and consumption contribute to these and other environmental challenges, and what kinds of dietary changes/transitions consistent with these goals are required. A major challenge is the high production and consumption of meat and too low consumption of fish, vegetables, and fruits. Meat production is a major source of emissions and, together with farmed fish, heavily dependent on imported feed ingredients, leaving a large land-use and water footprint in exporting countries while domestic land resources are not used optimally. Dietary patterns have changed drastically over the past 50 years, and in large parts of the population, meat consumption has doubled since the 1970s, rendering historic food culture less useful as a basis for present-day recommendations. The Nordics have Europe's lowest use of antibiotics in animal and fish production and have made some progress in reducing food waste along the food chain. A major opportunity is better alignment of food production and consumption based on local or regional production potentials, in conjunction with better and more constructive integration with the global food system while integrating novel technologies to reduce emissions and resource use.

Modelling seasonal and geographical n-3 polyunsaturated fatty acid contents in marine fish from the Northeast Atlantic Ocean.

Demand for n-3 polyunsaturated fatty acids (n-3 PUFAs) exceeds supply. Large-scale studies on effects of season and geography of n-3 PUFAs in marine fish from the Northeast Atlantic Ocean (NEAO) may be used to optimize utilization and improve nutrition security. Using a sinusoid model, seasonal cycles of n-3 PUFAs were determined and found to be species-specific and clearly pronounced for the pelagic zooplankton feeding species. The Greenland halibut showed very little seasonal variation. The n-3 PUFA content in North Sea autumn-spawning (NSAS) herring peaked in summer, while Norwegian spring-spawning (NSS) herring and mackerel had their peak in autumn. A time shift of peaks in n-3 PUFAs between the two herring stocks was detected, likely due to different spawning strategies in addition to a delay of n-3 PUFAs flux in the northern regions of the NEAO. This study demonstrates that consideration of nutrient contents, such as n-3 PUFAs, when organizing and structuring fishery approaches may improve overall nutritional yield. Based on total annual Norwegian fish landings and seasonal variation in n-3 PUFA contents, n-3 PUFAs yield could theoretically be increased from 13.79 kilo ton per year from the current fishing tactics, to 15.54 if the pelagic species were only caught during the time of their seasonal n-3 PUFA peaks. Pelagic fish is a good source for dietary n-3 PUFAs, but harvest timing will also influence n-3 PUFAs intake by human consumers. One portion of fatty fish harvested during winter/spring may not meet the weekly intake reference nutritional guidelines for n-3 PUFAs. Marine n-3 PUFAs yields also varied geographically and decreased southwards, with the lowest values in Skagerrak. This study can serve as a model to understand patterns of reproductive cycles and geographical distribution of n-3 PUFAs in fatty fish from the NEAO and the novel approach may be useful to support sustainable, seasonal fishing programmes for optimization of n-3 PUFAs yields.

Levels of mercury, arsenic, cadmium and lead in Northeast Atlantic mackerel (Scomber scombrus) from northern European waters.

Fillets from a total of 1245 Northeast Atlantic mackerel (Scomber scombrus) sampled in different fishing areas of the Northeast Atlantic during 2007-2016 were analysed for mercury, cadmium, arsenic and lead using ICPMS. Mercury levels varied from <0.01 to 0.36 mg/kg wet weight (ww) with a total mean of 0.046 mg/kg ww and were significantly higher in Skagerrak than in the North Sea, the Norwegian Sea and west of Scotland. Cadmium concentrations varied from <0.002 to 0.16 mg/kg ww with a mean value of 0.015 mg/kg ww. Only 0.24 % and 0.16 % of the sampled fish exceeded the EU's maximum levels for cadmium and mercury, respectively. Arsenic levels varied between 0.43 and 6.9 mg/kg ww with a mean value of 2.2 mg/kg ww and showed seasonal variation following variations in fat content. Lead concentrations were low and below the analytical limit of quantification (LOQ) in 97 % of the samples.

Climate change dynamics and mercury temporal trends in Northeast Arctic cod (Gadus morhua) from the Barents Sea ecosystem.

The Northeast Arctic cod (Gadus morhua) is the world's northernmost stock of Atlantic cod and is of considerable ecological and economic importance. Northeast Arctic cod are widely distributed in the Barents Sea, an environment that supports a high degree of ecosystem resiliency and food web complexity. Here using 121 years of ocean temperature data (1900-2020), 41 years of sea ice extent information (1979-2020) and 27 years of total mercury (Hg) fillet concentration data (1994-2021, n = 1999, ≥71% Methyl Hg, n = 20) from the Barents Sea ecosystem, we evaluate the effects of climate change dynamics on Hg temporal trends in Northeast Arctic cod. We observed low and consistently stable, Hg concentrations (yearly, least-square means range = 0.022-0.037 mg/kg wet wt.) in length-normalized fish, with a slight decline in the most recent sampling periods despite a significant increase in Barents Sea temperature, and a sharp decline in regional sea ice extent. Overall, our data suggest that recent Arctic amplification of ocean temperature, "Atlantification," and other perturbations of the Barents Sea ecosystem, along with rapidly declining sea ice extent over the last ∼30 years did not translate into major increases or decreases in Hg bioaccumulation in Northeast Arctic cod. Our findings are consistent with similar long-term, temporal assessments of Atlantic cod inhabiting Oslofjord, Norway, and with recent investigations and empirical data for other marine apex predators. This demonstrates that Hg bioaccumulation is highly context specific, and some species may not be as sensitive to current climate change-contaminant interactions as currently thought. Fish Hg bioaccumulation-climate change relationships are highly complex and not uniform, and our data suggest that Hg temporal trends in marine apex predators can vary considerably within and among species, and geographically. Hg bioaccumulation regimes in biota are highly nuanced and likely driven by a suite of other factors such as local diets, sources of Hg, bioenergetics, toxicokinetic processing, and growth and metabolic rates of individuals and taxa, and inputs from anthropogenic activities at varying spatiotemporal scales. Collectively, these findings have important policy implications for global food security, the Minamata Convention on Mercury, and several relevant UN Sustainable Development Goals.

Co-occurrence of contaminants in marine fish from the North East Atlantic Ocean: Implications for human risk assessment.

Marine fish from the North East Atlantic Ocean (NEAO) are nutrient rich and considered a valuable economic resource. However, marine fish are also a major dietary source of several contaminants, including persistent organic pollutants (POPs) and heavy metals. Using one of the world's largest seafood datasets (n > 25,000 individuals), comprising 12 commercially important fish species collected during 2006-2019 in the NEAO, we assessed the co-occurrence of elements and POPs, and evaluated potential risks to human consumers. Several positive correlations between concentrations of mercury (Hg), dioxins, polychlorinated biphenyls (PCBs) and polybrominated diphenyl ethers (PBDEs) were observed. Concentrations of Hg, dioxins, PCBs and PBDEs increased from North to South and associations between marine sediment contamination, sea temperature, and fish Hg and POPs concentrations were identified using multi-linear regression (MLR) models. In general, Hg concentrations in fillet and liver of fish were positively associated with increases in both sediment contamination and sea temperature. POPs concentrations in both fillet and liver were positively associated with increases in sediment contamination, and only POPs concentrations in the liver of benthopelagic and demersal species were found to be positively correlated with sea temperature. Using a probabilistic approach to estimate human contaminant exposure from seafood, we showed that intake of pelagic species posed the highest risk of dioxins and dioxin-like PCBs (DL-PCBs) exposure, while intake of benthopelagic and demersal species posed the highest risk of Hg exposure. This study can serve as a model to further understand the distribution, co-occurrence, and trends of contaminants in seafood harvested from the NEAO and their potential risks to human consumers.

Rapid temporal decline of mercury in Greenland halibut (Reinhardtius hippoglossoides).

Mercury (Hg) pollution in the ocean is an issue of global concern, however bioaccumulation regimes of this ubiquitous pollutant in marine apex predators have important knowledge gaps. Our fish length and stable isotope (δ15N and δ13C) normalized data of Greenland halibut (GH) (Reinhardtius hippoglossoides) showed that Hg bioaccumulation in fillet tissue decreased by ~35-50 %, over a ten-year period from 2006 to 2015 (n = 7 individual sampling years). Hg was predominantly in the methylmercury form (>77 %). Results from a Bayesian information theoretic model showed that GH Hg concentrations decreased with time and its associated declines in Hg air emissions, estimated trophic position, and a potentially lower degree of demersal prey use as indicated by temporal trend shifts in nitrogen (δ15N) and carbon (δ13C) stable isotope values. GH trophic shifts accounted for about one third of the observed temporal reduction in Hg. Our study demonstrates the importance of simultaneously considering Hg emissions, food web dynamics and trophic shifts as important drivers of Hg bioaccumulation in a marine, deep water fish species and highlights the effectiveness of Hg regulations on ocean apex predator Hg concentrations and overall seafood safety.

Cadmium in brown crab Cancer pagurus. Effects of location, season, cooking and multiple physiological factors and consequences for food safety.

Brown crab Cancer pagurus is appreciated as seafood in several European countries. However, cadmium levels in crabs can be elevated and their consumption may pose a hazard for human health. To assess if cadmium poses a threat to food safety in Norway, crabs were sampled at two different locations along the Norwegian coast: one in the South of Norway and one in the North of Norway. Cadmium levels were determined in different tissues (claw meat, hepatopancreas and inner meat). To highlight specific risk factors for cadmium, the concentration of cadmium was related to different exogenous (location, cooking and season) and physiological (size, sex, moulting stage, gonad maturation stage, condition) factors. The results confirmed previous findings of much higher cadmium levels in brown crab sampled in the North of Norway compared to the South. Cooking of crabs further led to higher concentrations in claw meat. The effect of season on cadmium levels was different in the North and South and no clear patterns could be identified, probably due to a high inter-individual variation in cadmium levels. Size showed a correlation with the total amount of cadmium for crabs in the North indicating an accumulation of cadmium over time; together with a slower growth, this may lead to the higher cadmium levels, observed in the crabs from Northern Norway. The risk connected to cadmium exposure when consuming brown crab mainly depends on the consumption pattern, the parts of the crab consumed and the origin of the crab. Regardless of origin, the consumption of claw meat does not display a consumer health risk. However, the consumption of meals consisting of inner meat only and inner meat of brown crab from Northern Norway may pose a health risk.

Spatial distribution of mercury in seawater, sediment, and seafood from the Hardangerfjord ecosystem, Norway.

Hardangerfjord is one of the longest fjords in the world and has historical mercury (Hg) contamination from a zinc plant in its inner sector. In order to investigate the extent of Hg transferred to abiotic and biotic ecosystem compartments, Hg and monomethylmercury (MeHg) concentrations were measured in seawater, sediment, and seafood commonly consumed by humans. Although total mercury in seawater has been described previously, this investigation reports novel MeHg data for seawater from Norwegian fjords. Total Hg and MeHg concentrations in seawater, sediment, and biota increased towards the point source of pollution (PSP) and multiple lines of evidence show a clear PSP effect in seawater and sediment concentrations. In fish, however, similar high concentrations were found in the inner part of another branch adjacent to the PSP. We postulate that, in addition to PSP, atmospheric Hg, terrestrial run-off and hydroelectric power stations are also important sources of Hg in this fjord ecosystem. Hg contamination gradually increased towards the inner part of the fjord for most fish species and crustaceans. Since the PSP and the atmospheric Hg pools were greater towards the inner part of the fjord, it is not entirely possible to discriminate the full extent of the PSP and the atmospheric Hg contribution to the fjord food web. The European Union (EU) Hg maximum level for consumption was exceeded in demersal fish species including tusk (Brosme brosme), blue ling (Molva dypterygia) and common ling (Molva molva) from the inner fjord (1.08 to 1.89 mg kg-1 ww) and from the outer fjord (0.49 to 1.07 mg kg-1 ww). Crustaceans were less contaminated and only European lobster (Homarus gammarus) from inner fjord exceeded the EU limit (0.62 mg kg-1 ww). Selenium (Se) concentrations were also measured in seafood species and Se-Hg co-exposure dynamics are also discussed.

Tracing Mercury Pollution along the Norwegian Coast via Elemental, Speciation, and Isotopic Analysis of Liver and Muscle Tissue of Deep-Water Marine Fish ( Brosme brosme).

Liver and muscle tissue of tusks ( Brosme brosme) have been analyzed for their THg and MeHg concentrations and Hg isotopic signatures for tracing Hg pollution along the Norwegian coast. Clear differences between tissue types and locations were established. At five of the eight locations, the Hg concentration in muscle exceeded the maximum allowable level of 0.5 mg kg-1 wet weight. δ202Hg values in both tissue types indicated that Hg speciation affects the bulk Hg isotopic signature. Tusk liver seems to be more sensitive to immediate changes and to anthropogenic inorganic Hg, while the muscle rather reflects the Hg accumulated over a longer period of exposure. The δ202Hg values of liver and muscle also enabled different sources of Hg and exposure pathways to be distinguished. δ202Hgmuscle-δ202Hgliver showed a clear correlation with the % MeHg in tusk liver for the coastal waters, but not for the fjords. The absence of significant differences in Δ199Hg values between both tissues of tusk from the same location suggests that in vivo metabolic processes are the underlying reason for the differences in Hg speciation and in δ202Hg values. This work highlights the importance of selecting different tissues of marine fish in future Hg monitoring programs.

Effects of geography and species variation on selenium and mercury molar ratios in Northeast Atlantic marine fish communities.

Methylmercury (MeHg) is a potent neurotoxin that bioaccumulates in seafood. Co-occurrence of selenium (Se) may affect the bioavailability and toxicity of MeHg in organisms. Here we report the concentrations of total mercury (Hg) and Se in 17 teleost fish species (n = 8459) sampled during 2006-2015 from the North East Atlantic Ocean (NEAO) and evaluate species variation and effects of geography. Mean Hg concentration ranged from 0.04 mg kg-1 ww in Atlantic mackerel (Scomber scombrus) and blue whiting (Micromesistius poutassou) to 0.72 mg kg-1 ww in blue ling (Molva dypterygia). Se concentrations were less variable and ranged from 0.27 mg kg-1 ww in Atlantic cod (Gadus morhua) to 0.56 mg kg-1 ww in redfish (Sebastes spp.). The mean Se:Hg molar ratio ranged from 1.9 in blue ling to 43.3 in mackerel. Pelagic species had the lowest Hg concentrations and the highest Se:Hg ratios, whereas demersal species had the highest Hg concentrations and the lowest Se:Hg ratios. Se and Hg concentrations were positively correlated in 13 of the 17 species. Hg concentrations increased from the North to South in contrast to the Se:Hg molar ratio which exhibited the opposite trend. Fish from fjord and coastal areas had higher concentrations of Hg and lower Se:Hg molar ratios compared to fish sampled offshore. All species had average Se:Hg molar ratios >1 and Hg concentrations were largely below the EU maximum level of 0.5 mg kg-1 ww with few exceptions including the deep water species tusk (Brosme brosme) and blue ling sampled from fjord and coastal habitats. Our results show that two fillet servings of tusk, blue ling or Atlantic halibut (Hippoglossus hippoglossus) exceeded the tolerable weekly intake of MeHg although the surplus Se may possibly ameliorate the toxic effects of MeHg. However, some individuals with selenium deficiencies may exhibit greater sensitivity to MeHg.

Factors influencing risk assessments of brominated flame-retardants; evidence based on seafood from the North East Atlantic Ocean.

Brominated flame-retardants (BFRs) such as polybrominated diphenyl ethers (PBDE) and hexabromocyclododecane (HBCD) are considered hazardous to human health. Due to their persistence, they are still present in the environment and in biota and seafood is major contributor of BFRs to human exposure. Here, we used data from >9700 samples of wild and farmed fish, fish feed and fish feed ingredients collected from the North Atlantic between 2006 and 2016 aiming to investigate factors influencing the risk assessments of BFRs. Due to most representative number of analyses, PBDEs were the main focus of investigation. Mean ∑PBDE in fillet samples ranged from below quantification in Atlantic cod fillet to 2.0 µg kg-1 in Atlantic halibut. The main congener contributing to the ∑PBDE in all species was BDE 47. Factors affecting the level of BFR in seafood were multifaceted, and the levels were within species mainly determined by fish age, geographical origin and time of sampling. BDE 47, 99, 153 and HBCD were selected for margin of exposure (MOE) evaluation. When other sources of BFR than seafood were excluded, our risk assessment showed low risk at the current dietary intake of seafood. However, the dietary intake of BDE 99 may be of concern for toddlers when all sources are considered. The choice of fish species, dietary studies, choice of statistics, as well as exposure from other sources than seafood, were all factors that influenced the final MOE of BFRs. We propose the use of regression on order statistics as a tool for risk assessment, to illustrate means and spreads in large surveillance datasets to avoid the issue of measurements below the limit of quantification. A harmonized, updated evaluation of the risk associated with exposure to BFRs from diet, air and dust is warranted, where the fish species most commonly consumed also is taken into consideration.

Tracing simultaneous cadmium accumulation from different uptake routes in brown crab Cancer pagurus by the use of stable isotopes.

High concentrations of cadmium in brown crab are an issue of food safety, and large variations between different areas have been found. To investigate the relative importance of dietary and aqueous uptake regarding the overall accumulation in brown crab, we used stable isotopes to trace the uptake from both routes simultaneously in the same animals. We demonstrated that the analytical challenges regarding background concentrations of natural isotope distribution and polyatomic interferences in the different matrices can be overcome with an appropriate analytical setup and modern mathematical corrections using a computer software. Cadmium was accumulated via both routes and was found in all measured organs at the end of the exposure phase. The obtained data were used to establish accumulation curves for both uptake routes and estimate accumulation parameters for hepatopancreas, as the most important organ in crab regarding total cadmium body burden. Using the estimated parameters in combination with naturally relevant cadmium concentrations in seawater and diet in a model, allowed us to predict the relative importance of the aqueous and dietary uptake route to the total hepatopancreas burden. According to the prediction, the dietary route is the main route of uptake in brown crab with a minimum of 98% of the accumulated cadmium in hepatopancreas originating from diet. Future studies addressing the source and accumulation of cadmium in crab should therefore focus on the uptake from feed and factors connected to foraging.

Iodine content of six fish species, Norwegian dairy products and hen's egg.

Iodine is a trace element required for the production of thyroid hormones, essential for metabolism, growth and brain development, particularly in the first trimester of pregnancy. Milk and lean fish are the main dietary sources of iodine in the Norwegian diet. Thus, the aim of the present study was to provide updated analysed values of iodine concentration in six fish species, 27 selected Norwegian iodine-rich dairy foods and Norwegian hen's eggs. The iodine concentrations in the wild fish species varied between 18 µg/100 g (Atlantic halibut) and 1,210 µg/100 g (pollack). The iodine concentration of cow milk varied between 12 and 19 µg/100 g and the iodine concentration of the eggs varied between 23 and 43 µg/100 g. The results in this study deviate somewhat from the current iodine concentrations in the Norwegian Food Composition Table. This deviation may have a large impact on the assessment of the iodine intake. Hence, updated knowledge about the variation in iodine level of fish, milk, dairy products and hen's egg are of great importance when estimating the iodine intake in the population. These data will contribute substantially to future estimations of dietary iodine intake and will be made available for the public Norwegian Food Composition Table.

Cadmium in the shore crab Carcinus maenas along the Norwegian coast: geographical and seasonal variation and correlation to physiological parameters.

Previously, high concentrations of cadmium have been found in the hepatopancreas of the edible or brown crab (Cancer pagurus) sampled from positions north of about 67° N, compared to regions further south along the Norwegian coast, with no clear understanding why. In order to study a similar organism in the same ecosystem, the present study analyzed 210 shore crabs (Carcinus maenas) from four different locations along the Norwegian coast, two in the North and two in the South. The physiological variables size, sex, molting stage, hepatosomatic index, carapace color, and gonad maturation were registered, in attempt to explain the high inter-individual variation in cadmium levels in hepatopancreas. In contrast to the brown crabs, the shore crabs showed no clear geographical differences in cadmium concentrations. This indicates physiological differences between the two crab species. No clear and consistent correlations were found between cadmium levels and physiological parameters, except for sex, where cadmium concentration in hepatopancreas was twice as high in males compared to females. The cadmium levels also varied with season, with approximately 40 and 60% lower cadmium concentration in April than August for male and female shore crabs, respectively. None of the analyzed cadmium concentrations in muscle meat from claws exceeded EUs food safety limit, and low cadmium levels in soup prepared from shore crabs clearly indicated that this dish is not problematic regarding food safety.

Total Mercury, Methylmercury, Inorganic Arsenic and Other Elements in Meat from Minke Whale (Balaenoptera acutorostrata) from the North East Atlantic Ocean.

Meat samples of 84 minke whales (Balaenoptera acutorostrata) mainly from the Barents Sea, collected between 1 May and 16 August 2011, were analyzed for total mercury, methylmercury, cadmium, lead, total arsenic, inorganic arsenic and selenium. The average total mercury concentration found was 0.15 ± 0.09 mg/kg, with a range from 0.05 to 0.49 mg/kg. The molar ratio of selenium to mercury varied between 1.0 and 10.3. Cadmium content ranged from 0.002 to 0.036 mg/kg, while the content of lead in whale meat ranged from <0.01 to 0.09 mg/kg. None of the whale samples exceeded established EU maximum levels for metals in fish muscle, but 4.8% and 6.8% of the samples exceeded Japanese maximum levels for total mercury and methylmercury, respectively, in whale meat. There was only minor variations in element concentrations between whales from different geographical areas, and cadmium was the only element were the concentration increased with increasing length.

Estimating human exposure to perfluoroalkyl acids via solid food and drinks: Implementation and comparison of different dietary assessment methods.

BACKGROUND: Diet is a major source of human exposure to hazardous environmental chemicals, including many perfluoroalkyl acids (PFAAs). Several assessment methods of dietary exposure to PFAAs have been used previously, but there is a lack of comparisons between methods. AIM: To assess human exposure to PFAAs through diet by different methods and compare the results. METHODS: We studied the dietary exposure to PFAAs in 61 Norwegian adults (74% women, average age: 42 years) using three methods: i) by measuring daily PFAA intakes through a 1-day duplicate diet study (separately in solid and liquid foods), ii) by estimating intake after combining food contamination with food consumption data, as assessed by 2-day weighted food diaries and iii) by a Food Frequency Questionnaire (FFQ). We used existing food contamination data mainly from samples purchased in Norway and if not available, data from food purchased in other European countries were used. Duplicate diet samples (n=122) were analysed by liquid chromatography coupled with tandem mass spectrometry (LC-MS/MS) to quantify 15 PFAAs (11 perfluoroalkyl carboxylates and 4 perfluoroalkyl sulfonates). Differences and correlations between measured and estimated intakes were assessed. RESULTS: The most abundant PFAAs in the duplicate diet samples were PFOA, PFOS and PFHxS and the median total intakes were 5.6ng/day, 11ng/day and 0.78ng/day, respectively. PFOS and PFOA concentrations were higher in solid than liquid samples. PFOS was the main contributor to the contamination in the solid samples (median concentration 14pg/g food), while it was PFOA in the liquid samples (median concentrations: 0.72pg/g food). High intakes of fats, oils, and eggs were statistically significantly related to high intakes of PFOS and PFOA from solid foods. High intake of milk and consumption of alcoholic beverages, as well as food in paper container were related to high PFOA intakes from liquid foods. PFOA intakes derived from food diary and FFQ were significantly higher than those derived from duplicate diet, but intakes of PFOS derived from food diary and FFQ were significantly lower than those derived from duplicate diet. We found a positive and statistically significant correlation between the PFOS intakes derived from duplicate diet with those using the food diary (rho=0.26, p-value=0.041), but not with the FFQ. Additionally, PFOA intakes derived by duplicate diet were significantly correlated with estimated intakes from liquid food derived from the food diary (rho=0.34, p=0.008) and estimated intakes from the FFQ (rho=0.25, p-value=0.055). CONCLUSIONS: We provide evidence that a food diary or a FFQ-based method can provide comparable intake estimates to PFOS and PFOA intakes derived from a duplicate diet study. These less burdensome methods are valuable and reliable tools to assess dietary exposure to PFASs in human studies.

Geographical trends of PFAS in cod livers along the Norwegian coast.

The level of perfluorinated alkyl substances (PFAS) was determined in North East Arctic cod (Gadus morhua) liver samples from 15 Norwegian fjords and harbors. Five harbors in the eastern part of Norway, six harbors in the western part and four harbours in the northern part. A total of 200 samples were analyzed for 16 PFAS. Determination of PFAS were carried out by LC-MS/MS following sample clean up by solid phase extraction and ultracentrifugation. The predominating PFAS was PFOS, which was found to be higher than the level of quantification (1.5 µg kg-1 wet weight) in 72% of the samples. The highest level of PFOS found was 21.8 µg kg-1 wet weight in a sample from Kragerø in the eastern part of Norway. A significantly higher level of PFOS was found in the eastern fjords and harbors compared to fjords and harbors in the western and northern part of Norway. Within the northern fjords and harbors elevated PFOS levels were found in Narvik, which may indicate a local source there. Variations in PFOS of the cod livers thus reflect differences in levels of pollution between the areas.

Assessment of Hg Pollution Released from a WWII Submarine Wreck (U-864) by Hg Isotopic Analysis of Sediments and Cancer pagurus Tissues.

Hg pollution released from the U-864 submarine sunk during WWII and potential introduction of that Hg into the marine food chain have been studied by a combination of quantitative Hg and MeHg determination and Hg isotopic analysis via cold vapor generation multicollector inductively coupled plasma-mass spectrometry (CVG-MC-ICP-MS) in sediment and Cancer pagurus samples. The sediment pollution could be unequivocally linked with the metallic Hg present in the wreck. Crabs were collected at the wreck location and 4 nmi north and south, and their brown and claw meat were analyzed separately. For brown meat, the δ202Hg values of the individuals from the wreck location were shifted toward the isotopic signature of the sediment and, thus, the submarine Hg. Such differences were not found for claw meat. The isotope ratio results suggest direct ingestion of metallic Hg by C. pagurus but do not offer any proof for any other introduction of the submarine Hg into the marine food chain.

An Outbreak of Norovirus Infection from Shellfish Soup Due to Unforeseen Insufficient Heating During Preparation.

Norovirus causes large outbreaks involving all age groups and are considered the most common cause of infectious foodborne diseases worldwide. The aim of this study was to describe a norovirus outbreak connected to insufficient heat treatment during preparation of a shellfish soup in serving portions, during a company Christmas celebration in Norway, December 2013. A questionnaire sent to the employees, showed that 67 % (n = 43) of the celebration participants, reported gastrointestinal symptoms including stomach pain, vomiting, diarrhoea and light fever in the period between 24 and 48 h post celebration. Several dishes were served, including shellfish soup made with carpet shell clams (Tapes rhomboides) in porcelain cups. Consuming this soup, was the only significant risk factor for infection. Norovirus GI and GII were detected in the remaining raw shellfish. To mimic the time and temperature obtained during bivalve soup preparation, raw chopped shellfish tissue and raw cepa onion were added in porcelain cups tempered to 20 °C. To each of these cups, boiling soup base was added. The temperature in the shellfish tissue was continuously recorded, and showed a maximum of 49 °C in the period between 3 and 7 min after adding the boiling soup base. After 1 h the temperature was 30 °C. This time and temperature combination was obviously not sufficient for inactivation of norovirus present in the shellfish tissue. In conclusion, the heat-absorbing capacity of cold ingredients, utensils and table wear porcelain should not be underestimated during food production. Consumers who want to avoid eating raw shellfish, should not assume that the shellfish tissue in preparation as described in our study is adequately heat treated.

Collaborative study on determination of mono methylmercury in seafood.

Eight laboratories participated in an inter-laboratory method-performance (collaborative) study of a method for the determination of mono methylmercury (MMHg) in foodstuffs of marine origin by gas chromatography inductively coupled plasma isotope dilution mass spectrometry (GC-ICP-IDMS) after dissolution, derivatisation and extraction of the species. The method was tested on seven seafood products covering both a wide concentration range and variations in the MMHg concentrations as well as matrix compositions. The samples were mussel tissue, squid muscle, crab claw meat, whale meat, cod muscle, Greenland halibut muscle and dogfish liver (NRCC DOLT-4), with MMHg concentrations ranging from 0.035 to 3.58mg/kg (as Hg) dry weight. Repeatability relative standard deviations (RSDr) for MMHg ranged from 2.1% to 8.7%. Reproducibility relative standard deviations (RSDR) ranged from 5.8% to 42%. All samples showed HorRat value below 1.0, except for the sample with the lowest MMHg content, mussel tissue, with a HorRat value of 1.6.