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Mitigation of contaminants in industrial processing was studied for prawns (cooked and peeled), Greenland halibut (cold smoked) and Atlantic salmon (cold smoked and trimmed). Raw prawns had significantly higher cadmium, chromium, iron, selenium and zinc content in autumn than in spring, while summer levels typically were intermediate. Peeling raw prawns increased mercury concentration but reduced the concentration of all other elements including inorganic arsenic, total arsenic, chromium, zinc, selenium but especially cadmium, copper and iron (p < 0.05), however interaction between seasons and processing was observed.Non-toxic organic arsenic in raw Greenland halibut (N = 10) and salmon (N = 4) did not transform to carcinogenic inorganic arsenic during industrial cold smoking. Hence inorganic arsenic was low (

Plastic is a general term for a diverse group of polymeric materials that are used in a plethora of products. They represent a major source of human exposure to endocrine disrupting chemicals, including phthalates, bisphenols and persistent organic pollutants (POPs). For humans, foods represent the main source of exposure, but common house dust can also be a significant source of exposure in small children.

Microplastics contamination of the aquatic environment is considered a growing problem. The ingestion of microplastics has been documented for a variety of aquatic animals. Studies have shown the potential of microplastics to affect the bioavailability and uptake route of sorbed co-contaminants of different nature in living organisms. Persistent organic pollutants and metals have been the co-contaminants majorly investigated in this field. The combined effect of microplastics and sorbed co-contaminants in aquatic organisms still needs to be properly understood. To address this, we have subjected zebrafish to four different feeds: A) untreated feed; B) feed supplemented with microplastics (LD-PE 125–250 µm of diameter); C) feed supplemented with 2% microplastics to which a mixture of PCBs, BFRs, PFCs and methylmercury were sorbed; and D) feed supplemented with the mixture of contaminants only. After 3 weeks of exposure fish were dissected and liver, intestine, muscular tissue and brain were extracted. After visual observation, evaluation of differential gene expression of some selected biomarker genes in liver, intestine and brain were carried out. Additionally, quantification of perfluorinated compounds in liver, brain, muscular tissue and intestine of some selected samples were performed. The feed supplemented with microplastics with sorbed contaminants produced the most evident effects especially on the liver. The results indicate that microplastics alone does not produce relevant effects on zebrafish in the experimental conditions tested; on the contrary, the combined effect of microplastics and sorbed contaminants altered significantly their organs homeostasis in a greater manner than the contaminants alone.

When microplastics pollute fish habitats, it may be ingested by fish, thereby contaminating fish with sorbed contaminants. The present study investigates how combinations of halogenated contaminants and microplastics associated with feed are able to alter toxicokinetics in European seabass and affect the fish. Microplastic particles (2%) were added to the feed either with sorbed contaminants or as a mixture of clean microplastics and chemical contaminants, and compared to feed containing contaminants without microplastics. For the contaminated microplastic diet, the accumulation of polychlorinated biphenyls (PCBs) and brominated flame retardants (BFRs) in fish was significantly higher, increasing up to 40 days of accumulation and then reversing to values comparable to the other diets at the end of accumulation. The significant gene expression results of liver (cyp1a, il1β,gstα) after 40 days of exposure indicate that microplastics might indeed exacerbate the toxic effects (liver metabolism, immune system, oxidative stress) of some chemical contaminants sorbed to microplastics. Seabass quickly metabolised BDE99 to BDE47 by debromination, probably mediated by deiodinase enzymes, and unlike other contaminants, this metabolism was unaffected by the presence of microplastics. For the other PCBs and BFRs, the elimination coefficients were significantly lower in fish fed the diet with contaminants sorbed to microplastic compared to the other diets. The results indicate that microplastics affects liver detoxification and lipid distribution, both of which affect the concentration of contaminants.

In this study, we explore the identity of a range of polyfluorinated surfactants (PFS) used for food contact materials, primarily to impart oil and water repellency on paper and board. PFS are of interest, as they can be precursors of poly- and perfluorinated alkyl substances (PFAS), of which several are persistent and are found worldwide in human blood and in the environment. To determine the elemental composition of PFS, we combined information from patents, chemical suppliers and analyses of industrial blends using ultra performance liquid chromatography-negative electrospray ionisation quadrupole time-of-flight mass spectrometry. At a high pH of 9.7, both non-ionic and anionic PFS were ionised and were recognised by negative mass defects of exact masses, and neutral fragment losses of n × 20 or n × 100 Da. More than 115 molecular structures were found in industrial blends from the EU, US and China, belonging to the groups of polyfluoroalkyl-mono- and di-ester phosphates (monoPAPS, diPAPS and S-diPAPS), -ethoxylates, -acrylates, -amino acids, -sulfonamide phosphates and -thio acids, together with residuals and synthesis byproducts. In addition, a number of starting materials such as perfluorooctane sulfonamide N-alkyl esters were analysed. Di- and trialkylated PAPS and S-diPAPS were found in migrates from European food contact materials. This study highlights the need to monitor for more types of PFS in order to map the sources of PFAS in humans and the environment.

A LC–MS–MS method for simultaneous determination of acrylamide, asparagine, fructose, glucose and sucrose in bread was developed. The method is based on aqueous extraction by blending. After centrifugation the samples were cleaned up by solid phase extraction on C18 cartridges conditioned with 2 mL of methanol and 2× 2 mL of water and subsequently flushed with sample solution before the actual analytical sample fractions were collected. Analytes were separated on a Hypercarb column (100 mm × 2.1 mm, 5 μm) and detected by tandem MS with electrospray ionisation. Acrylamide and saccharides were ionised in positive mode. Asparagine in wheat bread was detectable at lower levels using negative ion mode. To compensate for matrix induced signal suppression D3-acrylamide and 15N2-asparagine were used as internal standards for acrylamide and asparagine, respectively. Recoveries were in the range 93–112% for acrylamide spiked at 30, 250 μg kg−1 and 97–101% for asparagine spiked at 70, 140 mg kg−1. Sorbitol was used as internal standard for fructose and glucose. Samples were diluted to obtain acceptable recoveries in saccharide analyses. LODs were 13 μg kg−1 for acrylamide and 2 mg kg−1 for asparagine in wheat bread.

A method for analysing carbamates and other relatively polar pesticides by LC–MS–MS with electrospray ionisation has been developed. The method is based on extraction by ultrasonication using a methanolic ammonium acetate–acetic acid buffer. After centrifugation the samples are filtered in Miniprep filter HPLC vials and detected by LC–MS–MS. To compensate for variations in the MS response [ 13 C 6 ]-carbaryl was used as internal standard and matrix-matched pesticide solutions were used as external standards for the quantification. The method has been validated for the matrices apple, avocado, carrot, lettuce, orange, potato and wheat at the spiking levels—0.02; 0.04 and 0.20 mg kg−1. Recoveries were generally in the range 70–120%. Results from participation in three intercomparisons proved the accuracy of the method. As the analytical procedure does not include any concentration or cleanup steps, it is easy and fast to perform, making it applicable for routine analysis in large pesticide monitoring programmes.

An analytical method for analysing acrylamide in coffee was validated. The analysis of prepared coffee includes a comprehensive clean-up using multimode solid-phase extraction (SPE) by automatic SPE equipment and detection by liquid chromatography tandem mass spectrometry using electrospray in the positive mode. The recoveries of acrylamide in ready-to-drink coffee spiked with 5 and 10 μg l−1 were 96±14% and 100±8%, respectively. Within laboratory reproducibility for the same spiking levels were 14% and 9%, respectively. Coffee samples (n = 25) prepared twice by coffee machines and twice by a French Press Cafetiere coffee maker contained 8±3 μg l−1 and 9±3 μg l−1 acrylamide. Five ready-to-drink instant coffee prepared twice contained 8±2 μg l−1. Hence, the results do not show significant differences in the acrylamide contents in ready-to-drink coffee prepared by coffee machine, French Press or from instant coffee. Medium roasted coffee contained more acrylamide (∼10 μg l−1) than dark roasted coffee (∼5 μg l−1). Males aged 35–45 years, drinking on average 1.1 l coffee per day are exposed to the highest doses of acrylamide from coffee. The dietary intake of acrylamide from coffee comprises, on an average, 10 μg day−1 for males and 9 μg day−1 for females aged 35–45 years. Probabilistic modelling of the exposure of Danish consumers (all adults) to acrylamide from coffee shows a mean exposure of 6.5 μg day−1 and a 95 percentile of 18 μg day−1.

Atmospheric day and night concentrations of particulate organic nitrates (PON) and several other air pollutants were measured in the summer 1995 over an open-land area in Denmark. The sampling of PON was evaluated comparing 24 h samples with two sets of 12 h samples. These results indicate that the observed low contribution of PON to NOy is real and not the result of an extensive loss during the sampling. Empirical relationships between the vapour pressure and chemical formula of organic compounds were established in order to evaluate the gas/particle distribution of organic nitrates. A positive correlation between the PON to NOz ratio and the inverse temperature may indicate that the organic nitrates associated with particles also may be present in the gas phase. The observed day and nighttime levels of PON were of the same magnitude, although the day to night ratio varied from 0.4 to 4.4.

Observations of the concentration of several nitrogen containing compounds at five rural Scandinavian sites during March–June 1993 are reported. Total nitrate (NO3- + HNO3) and total ammonium (NH4+ + NH3) were measured by denuder and filter pack. In general the methods agree well. At all sites the particulate fraction dominated, with the largest fraction of NO3- and the lowest of NH4+ at the sites which were closest to the emission sources. The fraction of NO3- of total nitrate increased with increasing NO2 concentrations, indicating that the nighttime conversion of NO2 to NO3- is an important route of formation for NO3-. A positive correlation was found between HNO3 and O3 in June at all sites, while no correlation was found early in the spring. Model calculations were made with a lagrangian boundary layer photooxidant model for the whole period, and compared to the measured concentrations. The calculated ratio between mean observed and modelled daily maximum concentrations of ozone over the measurement period were within +/−10% at all sites. The models ability to describe the daily ozone maximum concentration was satisfactory with an average deviation of 19–22% from the observed concentrations. HNO3 was underestimated by over 50% at all sites except the one closest to the emission sources. The correlation between modelled and observed concentrations was generally best for the sites with shortest transport distance from the sources of emission.

Formic and acetic acid measured as daily averages in 1993–1994show equal and highly correlated concentrations up to 3 ppb in the summer(May–August). In the winter (October–March) the formicacid/acetic acid ratio was 0.6 and the formic acid concentrations wereusually below 1 ppb. In winter the carboxylic acids correlate withOx, NOy, SO2 and particulatesulphur. The main sources are suggested to be ozonolysis of anthropogenicalkenes and reactions between peroxyacetyl radicals and RO2radicals. In spring–summer the carboxylic acids correlate withO3, Ox, HNO3, PAN,NOy, SO2, particulate sulphur and temperature.In addition to the sources of the winter a contribution from ozonolysis ofbiogenic alkenes is likely. Quite similar formic acid/acetic acid ratios forall wind directions suggest that the source(s) are atmospheric oxidationprocesses distributed over large areas. The highest concentrations occurringfor winds from east to south and the correlation with e.g., particulatesulphur indicate chemical production in polluted air masses during longrange transport.

Surface ozone data from 25 Europeanlow-altitude sites and mountain sites located between79°N and 28°N were studied. The analysiscovered the time period March 1989–February 1993.Average summer and winter O3 concentrations inthe boundary layer over the continent gave rise togradients that were strongest in the north-west tosouth-east direction and west-east direction, respectively. WintertimeO3 ranged from 19 to 27 ppbover the continent, compared to about 32 ppb at thewestern border, while for summer the continentalO3 values ranged between 39 and 56 ppb and theoceanic mixing ratios were around 37 ppb. In the lowerfree troposphere average wintertime O3 mixingratios were around 38 ppb, with only an 8 ppbdifference between 28°N and 79°N. For summerthe average O3 levels decreased from about 55 ppbover Central Europe to 32 ppb at 79°N. Inaddition, O3 and Ox(= O3 + NO2)in polluted and clean air were compared. Theamplitudes of the seasonal ozone variations increasedin the north-west to south-east direction, while thetime of the annual maximum was shifted from spring (atthe northerly sites) to late summer (at sites inAustria and Hungary), which reflected the contributionof photochemical ozone production in the lower partsof the troposphere.

The pollution loads by hydrocarbons and some organochlorines have been investigated in common mussels (Mytilus edulis L.) from the Inner Danish Waters. The ranges of pollutant concentrations were 7.5–108 μg g−1 wet wt for paraffin-naphthene(p-n-)-hydrocarbons, 10–111 ng g−1 wet wt (Σ14 PAH) for polyaromatic hydrocarbons, 3–328 ng g−1 wet wt (Σ7 chlorobiphenyl) for polychlorinated biphenyls, 2.4–67 ng g−1 wet wt for ΣDDT, 0.3-3.1 ng g−1 wet wt for α-HCH, 0.6–7.4 ng g−1 wet wt for γ-HCH and 0.05-0.74 ng g−1 wet wt for HCB. An interpretation of the physiological parameter, the condition index (measured as the ratio of dry weight of soft tissue to (shell length)3 and ‘normalized’ with respect to shell length) in relation to the lipid content showed a good correlation (r = 0.76, p = 0.0001). The condition index showed a significant negative correlation with the polyaromatic hydrocarbons (Σ14 PAH, r = −0.48, p = 0.01) and a weaker negative correlation with the p-n-hydrocarbons (r = −0.36, p = 0.08).

A new method for the analysis of 25 polycyclic aromatic hydrocarbon (PAH) compounds in fish was developed, validated, and used for the quantification of PAHs in 180 industrially smoked fish products. The method included pressurized liquid extraction, gel-permeation chromatography (Bio-beads S-X3), solid-phase extraction (silica gel), and gas chromatography-mass spectrometry analysis. The sum concentration of 25 PAHs ([summation operator]PAH(25)) was highest in smoked herring (n = 3) and mackerel fillets (n = 13), with an average concentration of 320 and 235 microg kg(-1), respectively. Lowest average [summation operator]PAH(25) concentrations were obtained for indirectly smoked trout (26 microg kg(-1)). Principal component analysis was used to correlate processing parameters to PAH concentrations and to identify the effects of these parameters. The analysis showed that for salmon hot-smoking conditions lead to higher SigmaPAH(25) than cold smoking, and for other fish species direct smoking leads to higher SigmaPAH(25) than indirect smoking. Also, the usage of common alder increases the PAH contamination compared with beech. The effects of smoking time, combustion temperatures, and two types of smoke-generating material on the [summation operator]PAH(25) were also tested in a pilot plant study with smoked trout as a model fish. In addition to confirming that increased combustion temperatures and usage of common alder in comparison with beech increased [summation operator]PAH(25), it was also revealed that the PAH concentration decreased in the order fish skin >> outer layer of the fish muscle > inner part of the fish muscle.

Methods, parameterisations and models have been developed, which give insight in processes that are important for deposition of nitrogen compounds to the sea. This knowledge has been applied to the Kattegat Strait for which a nitrogen deposition of 960 kg N km-2 yr-1 was calculated with an atmospheric transport model.

Traffic in cities and on highways is an important contributor to NO y atmospheric pollution in open areas. In this situation both the concentration and composition of NO y compounds show a wide variation and are dependent on meteorological and atmospheric chemical conditions. The proportion of NO z compounds (HNO 3 + nitrate + PAN + PPN + N 2 O 5 + organic nitrates) increases while that of NO x decreases with increasing ozone concentrations. The dry deposition velocity of NO 2 was determined to be 0.2 cm s −1 above vegetation. The dry deposition contribution of the different NO y compounds was evaluated. The possiblity that a significant contribution is caused by a group of unidentified NO y compounds cannot be excluded. Therefore, future investigations of atmospheric pollution of sensitive ecosystems, at conditions with a relatively high atmospheric content of NO y compared to that of NH 3 , ought to take into consideration the possible contribution from unidentified NO y compounds. This also implies that atmospheric research into the identity, occurrence, sources and sinks of these compounds—as well as further developments of sampling and analytical methods—should be given a high priority.

The presence of furan in a broad range of heat processed foods (0-6000 μg kg(-1)) has received considerable attention due to the fact that this heat induced contaminant is considered as a "possible carcinogenic compound to humans". Since a genotoxic mode of action could be associated with furan-induced tumor formation, current human exposure levels to this contaminant may indicate a risk to human health and the necessity for its mitigation. This review summarizes and focuses on the main issues of furan toxicity, human dietary exposure to furan and mechanisms of furan formation. Additionally, the role of some critical factors such as heating conditions, pH and matrix microstructure are discussed in order to propose some potential methodologies for furan mitigation in a wide range of heated foods.