Polycyclic aromatic hydrocarbons and halogenated persistent organic pollutants in canned fish and seafood products: smoked versus non-smoked products

In this study, levels of several groups of environmental contaminants represented by PAHs, PCBs, organochlorine pesticides and polybrominated diphenyl ethers were determined in various types of canned smoked and non-smoked fish and seafood products (54 samples) obtained from the Czech market. PAHs were detected in all of the studied samples, and at least one of the target halogenated persistent organic pollutants was present above the LOQ in 85% of the samples. The levels of PAHs, PCBs, organochlorine pesticides (mainly DDTs) and polybrominated diphenyl ethers found in the canned products varied in the range of 1.4–116?µg?kg^?1, 0.6–59.6?µg?kg^?1, 0.6–82.7?µg?kg^?1 and 0.1–2.1?µg?kg^?1 can content, respectively. Smoked sprats were the most contaminated fish product (n?=?12) in which the highest levels of both PAHs and persistent organic pollutants were found. In 67% of the samples of smoked sprats in oil, the level of benzo[a]pyrene exceeded the maximum level of 5?µg?kg^?1 established for smoked fish by European Union legislation. The distribution of target analytes between oil and fish fractions was also assessed. Significantly higher levels of PAHs were measured in the oil fraction.     

Determination of furan levels in commercial samples of baby food from Brazil and preliminary risk assessment

Commercial baby food samples available on the Brazilian market (n = 31) were analysed for furan content using a gas chromatography-mass spectrometry method preceded by solid-phase microextraction. A limit of detection of 0.7 µg kg^?1, a limit of quantitation of 2.4 µg kg^?1, mean recoveries varying from 80% to 107%, and coefficients of variation ranging from 5.6% to 9.4% for repeatability and from 7.4% to 12.4% for within-laboratory reproducibility were obtained during an in-house validation. The levels of furan found in the samples were from not detected to 95.5 µg kg^?1. Samples containing vegetables and meat showed higher furan levels as compared with those containing only fruits. An exposure assessment showed furan intakes up to 2.4 µg kg^?1 body weight day^?1 (99th percentile) for babies fed exclusively with commercial baby foods. Margins of exposure obtained from intakes estimated in this work indicated a potential public health concern.     

Occurrence of 3-MCPD fatty acid esters in human breast milk

A series of twelve breast milk samples were analysed by gas chromatography-mass spectrometry (GC/MS) operated in selected ion monitoring mode for 3-chloropropane-1,2-diol (3-MCPD). Whilst none of the samples contained 3-MCPD above the limit of detection of 3 μg kg^?1 milk, all contained high amounts of 3-MCPD esterified with higher fatty acids. The levels of 3-MCPD released by hydrolysis of these esters (bound 3-MCPD) ranged from the limit of detection (300 μg kg^?1, expressed on a fat basis) to 2195 μg kg^?1; with a mean level of bound 3-MCPD of 1014 μg kg^?1, which corresponded to 35.5 μg kg^?1 milk. The presence of bound 3-MCPD was confirmed using orthogonal gas chromatography coupled with high-speed time-of-flight mass spectrometry analysis for four randomly selected breast milk samples. Six breast milks collected from one of the nursing mothers 14–76 days after childbirth contained bound 3-MCPD within the range of 328–2078 μg kg^?1 fat (mean 930 μg kg^?1 fat). The calculated bound 3-MCPD content of these samples was within the range of 6 and 19 μg kg^?1 milk (mean of 12 μg kg^?1 milk). The major types of 3-MCPD esters were the symmetric diesters with lauric, palmitic, and oleic acids, and asymmetric diesters with palmitic acid/oleic acid among which 3-chloro-1,2-propanediol 1,2-dioleate prevailed.     

Survey of the histamine content in fish samples randomly selected from the Greek retail market

The histamine content of fish sold in the Greek retail market was surveyed and the performance of high-performance liquid chromatography (HPLC) and enzyme-linked immunoabsorbant assay (ELISA) methods for the determination of histamine were compared. A total of 125 samples of fresh and canned tuna, fresh and canned sardines, deep frozen swordfish, smoked and deep frozen mackerel, anchovies, salted and smoked herring were analysed by HPLC (55 samples), ELISA (106 samples) and both methods (36 samples). Histamine levels as determined by HPLC, ranged from 2.7 mg kg^?1 to 220 mg kg^?1. The highest histamine concentrations obtained by HPLC were found in herring and anchovy samples. Eight out of the 55 samples (14.5%) analysed by HPLC, exceeded the US Food and Drug Administration (USFDA) limit (50 mg kg^?1), while 16 out of the 106 samples (15%) analysed by ELISA exceeded the limit. The results show that for histamine concentrations below 50 mg kg^?1, there is good agreement between the ELISA and HPLC but above 50 mg kg^?1 big differences were found.     

Taste recognition threshold concentrations of styrene in oil-in-water emulsions and yoghurts

Taste recognition threshold concentrations (TRTC) of styrene were determined in samples of oil-in-water emulsions (30–300 g kg^?1 oil) and yoghurts (1–30 g kg^?1 fat), spiked with styrene. The observed TRTC increased linearly with increasing fat content and ranged from 0–3 to 2–1 mg kg^?1 for the emulsions and from 36 to 171 g kg^?1 for the yoghurts. Styrene equilibrium partition coefficients between emulsions and their respective vapour phases were determined. The concentrations of styrene in the continuous aqueous phase of the emulsions and yoghurts were calculated at the TRTC. The styrene concentrations in the continuous phase had constant values of about 15 g kg^?1 indicating that perception of styrene for oil-in–water emulsions is determined by the aqueous phase of the emulsion. The concentrations of styrene in the vapor phases above the emulsions and yoghurts were also calculated and were found to be constant at the TRTC. This relationship probably resulted from the equilibrium of distribution of styrene between the respective phases. Commercial yoghurt packed in polystyrene beakers contained styrene levels in the range 2–11 g kg^?1, much lower then the TRTC reported.     

Iron and tin content of canned fruit juices and nectars

A survey of the iron and tin content of twelve different types of canned fruit juices and nectars revealed that, of the 122 cans examined, 23 (or 18·9%) contianed iron in excess of 15 mg kg^?1 and 16 (or 13·1%) contained tin in excess of 250 mg kg^?1. Apple juice and tomato juice were found to contain particularly high levels of iron, the maximum level recorded being 42·6 mg kg^?1. Mango juice and orange juice exhibited significant non-compliance with recommended Codex tolerance limits for tin. Statistical analysis showed that, at the 5% probability level, the mean iron contents of products packed in completely unlacquered and end-lacquered cans were not significantly different from each other, but were significantly lower than the mean iron content of products packed in fully lacquered cans. The mean tin content fell in the order unlacquered > end-lacquered > fully lacquered cans.     

A survey of styrene monomer levels in foods and plastic packaging by coupled mass spectrometry—automatic headspace gas chromatography

An extensive UK survey of styrene monomer levels in styrene based plastic packaging materials and their contained foods (133 samples) has been carried out, examining a wide range of retail foods of different brand names and including yogurts, creams, salads, coleslaws, soft cheeses, margarines, hot and cold beverages from dispensing machines, spreads, fresh and cooked meats, candied fruits, fresh strawberries, and take-away ‘fast’ foods. Analysis by headspace gas chromatography of styrene levels in the plastic containers showed levels of monomer ranging from 16 to 1300 mg kg^?1 although the majority of containers (73%) had styrene levels in the range 100–500 mg kg^?1 and only five plastic tubs had levels exceeding 1000 mg kg^?1. Analysis of the food contents of the plastic containers by automated headspace gas chromatography with single ion monitoring mass spectrometric detection showed levels of the monomer ranging from < 1 μg kg^?1 to 200 μg kg^?1, although the majority of foods (77%) had styrene levels below 10 μg kg^?1, and 26% of the total number analysed had levels below 1 μg kg^?1.     

Development of an analytical method and survey of foods for furan, 2-methylfuran and 3-methylfuran with estimated exposure

Furan has been found to form in foods during thermal processing. These findings, a classification of furan as a possibly carcinogenic to humans, and a limited amount of data on the concentration of furan in products on the Canadian market prompted the authors to conduct a survey of canned and jarred food products. Methyl analogues of furan, 2-methylfuran and 3-methylfuran, were analysed concurrently with furan via a newly developed isotope dilution method, as these analogues were detected in foods in the authors’ earlier work and are likely to undergo a similar metabolic fate as furan itself. The paper reports data on 176 samples, including 17 samples of baby food. The vast majority of samples were packaged in cans or jars. Furan was detected above 1 ng g^?1 in all non-baby food samples with a median of 28 ng g^?1 and concentrations ranging from 1.1 to 1230 ng g^?1. Also, 96% of these samples were found to contain 2-methylfuran above 1 ng g^?1 with a median of 12.8 ng g^?1 and a maximum concentration of 152 ng g^?1, while 81% of samples were found to contain 3-methylfuran above 1 ng g^?1 with a median of 6 ng g^?1 and a maximum concentration of 151 ng g^?1. Similarly, furan was detected above 1 ng g^?1 in all baby food samples with a median of 66.2 ng g^?1 and concentrations ranging from 8.5 to 331 ng g^?1. Also, 100% of these samples were found to contain 2-methylfuran above 1 ng g^?1 with a median of 8.7 ng g^?1 and a maximum concentration of 50.2 ng g^?1, while 65% of samples were found to contain 3-methylfuran above 1 ng g^?1 with a median of 1.6 ng g^?1 and a maximum concentration of 22.9 ng g^?1. Additionally, three coffee samples were analysed ‘as is’, without brewing, and were found to have high levels of furans, especially 2-methylfuran, at a maximum of 8680 ng g^?1. Using this data set, dietary exposures to furan and total furans were calculated. Average furan and total furan intakes by adults (≥20 years) were estimated at approximately 0.37 and 0.71 µg kg^?1 of body weight day^?1 respectively.     

Total mercury in milled rice and brown rice from China and health risk evaluation

Total mercury (THg) levels in 440 pairs of milled rice samples and brown rice samples from 15 major rice grain-producing provinces of China were measured and the associated health risk via rice consumption for different age categories of Chinese population was also assessed. THg contents were measured by a direct mercury analyser and the limit of detection (LOD) was 1.5 μg kg^?1. The THg levels for milled rice samples and brown rice samples varied from non-detected to 17.8 μg kg^?1 and 1.5 to 25.4 μg kg^?1, respectively, with a mean level of 3.4 μg kg^?1 and 4.9 μg kg^?1, respectively. The THg levels in all milled and brown rice samples were generally low, except three brown rice samples having concentrations above the legally set value for cereals (20 μg kg^?1 Hg). THg intakes for different age categories were estimated according to THg content and corresponding rice consumption and the associated health risk was evaluated by the corresponding provisional tolerable weekly intake (PTWI) for THg (5.0 μg kg^?1 bw week^?1), which was established by the Joint FAO/WHO Expert Committee on Food Additives (JECFA). The 50th percentile of the THg intakes via milled rice and brown rice consumption for different age categories was in the range 0.09–0.19 μg kg^?1 bw week^?1 and 0.14–0.27 μg kg^?1 bw week^?1, respectively, well below the PTWI, suggesting that the associated health risk is relatively low. However, the 99.9th percentile of the THg intakes for 2–4-year-old children amounted up to 20.6% of the PTWI (milled rice) and 29.5% of the PTWI (brown rice), which deserves attention.     

Dietary Intake of Fluoride in the United Kingdom and Fluoride Content of Some Foodstuffs

Using samples from the Total Diet Study, the average dietary intake per person of fluoride in the United Kingdom is estimated to be 1.82 mg day^?1. Beverages account for 71% of the total dietary intake and tea contributes most to the intake from the beverages group. Above-average consumption of tea, as recorded in Great Britain, could result in fluoride intakes as high as 8.9 mg day^?1. It is estimated that tap water containing 1 mg litre^?1 of fluoride could increase normal dietary intakes by 54%. Individual foods have been analysed and the results show that tea infusions and foods containing skin or bone have higher fluoride concentrations than other foods. Concentrations as high as 44 mg kg^?1 were found in the tail meat of krill, and a sample of mechanically deboned meat contained 2.8 mg kg^?1 fluoride. Samples of flour, bread, vegetables, meat and fish products and infant foods generally contained less than 1 mg kg^?1 of fluoride. Soft drinks from an area with a fluoridated water supply had a higher fluoride concentration than samples taken from an area with unfluoridated water.     

Survey of phthalate levels in Italian oily foods contained in glass jars with PVC gaskets

A method based on gas chromatography/tandem mass spectrometry was used to assess levels of twelve phthalates in 50 samples of oily foods packed in glass jars with metal closure obtained from a retail market. The amounts of di-methyl phthalate, di-ethyl phthalate, di-propyl phthalate, di-butyl phthalate, di-pentyl phthalate, benzyl butyl phthalate, di-cyclohexyl phthalate, di-n-octyl phthalate, di-isononyl phthalate and di-isodecyl phthalate in all samples analysed were less than the limit of quantification (LOQ). Di-(2-ethylhexyl) phthalate was detected in 20 samples in the range from 0.1 to 6 mg kg^?1 with an average of 1.0 mg kg^?1, and it exceeded the specific migration limit (SML) of 1.5 mg kg^?1 in five cases with an average of 3.0 mg kg^?1. Di-isobutyl phthalate was found in four samples at 0.1–0.4 mg kg^?1. The PVC gaskets used for the lids were negative for all tested phthalates, suggesting that the contamination of the foods originated from other sources, e.g. olive oil.     

Determination of furan in jarred baby food purchased from the Spanish market by headspace gas chromatography-mass spectrometry (HS-GC-MS)

The aim of this paper is to offer a method based on headspace gas chromatography-mass (HS-GC-MS) spectrometry technique in-house validated and use to estimate furan concentrations in jarred baby-food samples purchased from the Spanish market. The validation was performed according to ISO 17025 and European Food Safety Authority (EFSA) requirements and the results obtained (limit of detection (LOD) = 0.05 µg kg^?1; limit of quantification (LOQ) = 4 µg kg^?1, lowest validated level; relative standard deviation (RSD) = 3.1–10.5%; recoveries = 85.4–101.5%) confirm that this method is fit for the routine analysis of furan in jarred baby food control. Furan was analysed in 39 different baby-food samples and the mean levels varied between 64.6 µg kg^?1 (rice and chicken samples) and less than or equal to the LOQ (fruit-based samples). The mean concentrations found for the different matrices were 5.0, 37.8, 25.2, 33.8 and 30.5 µg kg^?1 for fruit, vegetables, meat/vegetables, fish/vegetables and dairy-containing baby foods, respectively. According to the statistical analyses, fruit-based baby-food samples had significantly lower concentrations of furan. Mean values for the other matrices were at least five times higher, and this is in accordance with the levels reported in other studies.     

Evaluation of acrylamide and selected parameters in some Turkish coffee brands from the Turkish market

The purpose of this study was to measure acrylamide (AA) levels and selected parameters of different traditional Turkish coffees. AA, 5-hydroxymethylfurfural (HMF), total reducing sugar, protein, pH, moisture, dry matter (DM) as well as ash, caffeine and soluble solids content (SSC) in DM, L*, a*, b* colour parameters of coffee samples were determined and the correlation between AA level and these parameters were investigated. A total of 36 coffee samples (20 Turkish, 8 Dibek and 8 Terebinth coffee) from the Turkish market were examined. A liquid chromatography-tandem mass spectrometry (LC-MS/MS) method was validated for the detection and quantitation of AA in coffee samples. The calibration curve was linear (R² ≥ 0.999) over the range of 30–1000 μg kg^?1. The limit of detection (LOD) and limit of quantification (LOQ) were found as 4.6 μg kg^?1 and 15.5 μg kg^?1, respectively. The amounts of AA in analysed coffee samples were in the range 31.1 ± 0.6 to 323.4 ± 5.4 µg kg^?1. The highest mean AA levels were found in Terebinth coffees (240.3 μg kg^?1) followed by Turkish coffees (204.3 µg kg^?1) and then Dibek coffees (78.6 µg kg^?1). No tested Turkish coffee samples had an AA concentration above the indicative value (450 µg kg^?1) for roast coffee recommended by the European Commission (EC) in 2011. In addition, a strong positive correlation was found between HMF values and AA amounts of selected coffee types.     

Survey of furan in foods and coffees from five European Union countries

Canned and jarred baby foods (74), canned and jarred adult foods (63) and 70 coffees sold in Belgium, Italy, Portugal, Spain and The Netherlands were analysed for their furan content using a validated automated headspace GC–MS procedure. Seven balsamic vinegars from Italy and Spain were also analysed. All 74 baby food samples contained detectable furan, with an average level of 37 ng/g. A total of 54 of 63 canned and jarred foods contained detectable furan with an average level of 24 ng/g. Levels of furan in coffee as consumed were very variable and reflected different preparation methods and coffee strengths. Over 50% of Italian samples contained more than 200 ng/g, whereas over 20% of Belgian coffees contained less than 21 ng/g furan. Some brews made from fine grained coffee contained much more furan than did brews made from normal or coarse grained coffee. Although furan was low in most instant coffees, two Italian products “instant espresso” and “instant mocha” contained about 150 ng/g furan. Balsamic vinegars from Spain contained 159–662 ng/g of furan; however, other samples from Spain and Italy contained only 6–25 ng/g.     

Occurrence of furan in commercial processed foods in Brazil

Selected commercial processed foods available in the Brazilian market (306 samples) were analysed for furan content using a validated gas chromatography-mass spectrometry method preceded by headspace solid phase micro-extraction (HS-SPME-GC/MS). Canned and jarred foods, including vegetable, meat, fruit and sweet products, showed levels up to 32.8?µg?kg^?1, with the highest concentrations observed in vegetables and meats. For coffee, furan content ranged from 253.0 to 5021.4?µg?kg^?1 in the roasted ground coffee and from not detected to 156.6?µg?kg^?1 in the beverage. For sauces, levels up to 138.1?µg?kg^?1 were found. In cereal-based products, the highest concentrations (up to 191.3?µg?kg^?1) were observed in breakfast cereal (corn flakes), cracker (cream crackers) and biscuit (wafer). In general, these results are comparable with those reported in other countries and will be useful for a preliminary estimate of the furan dietary intake in Brazil.     

Ergot alkaloids in rye flour determined by solid-phase cation-exchange and high-pressure liquid chromatography with fluorescence detection

Ergot alkaloids are mycotoxins that are undesirable contaminants of cereal products, particularly rye. A method was developed employing clean-up by cation-exchange solid-phase extraction, separation by high-performance liquid chromatography under alkaline conditions and fluorescence detection. It is capable of separating and quantifying both C8-isomers of ergocornine, α-ergocryptine, ergocristine, ergonovine, and ergotamine. The average recovery was 61% ±?10% with limits of detection from 0.2 to 1.1 µg kg^?1. Twenty-four unknown rye flour samples from Danish mills contained on average 46 µg kg^?1 with a maximum content of 234 µg kg^?1. The most common ergot alkaloids were ergotamine and α-ergocryptine including their C8-isomers. A total of 54% of the ergot alkaloids were detected as C(8)-S isomers.     

3-Monochloro-1,2-propandiol (3-MCPD) in soy sauce from the Bulgarian market

The 3-monochloro-1,2-propandiol (3-MCPD) levels in soy sauces which contained hydrolysed vegetable protein were evaluated for the Bulgarian market. For analysis of 3-MCPD, a gas chromatography–mass spectrometry (GC-MS) method was applied with a linear range of 0.03–2.00 μg mL^?1 and a limit of detection (LOD) of 2.3 μg kg^?1 and a limit of quantification (LOQ) of 3.4 μg kg^?1. At these levels, the standard deviation was 5.1%, with recoveries between 81% and 102%. The method was applied to the analysis of 21 samples of soy sauce from the Bulgarian market. Results ranged from 3.7 to 185.6 μg kg^?1. Soy sauces produced from hydrolysed soy protein contained higher levels of 3-MCPD than naturally fermented sauces. In 38.4% of samples of Bulgarian origin, the 3-MCPD content was above the EU limit of 20 μg kg^?1. In all analysed samples, 33.3% had a 3-MCPD content above the EU limit.     

The proximate composition and some minor constituents of poppy seeds

The proximate chemical composition of poppy seeds, along with minerals and water-soluble vitamins content was investigated. The compositions of the fatty acids and tocopherols of the extracted oil were also determined. The proximate analysis of poppy seeds showed the following composition: (440 g kg^?1), protein (211 g kg^?1), moisture (50 g kg^?1), ash (63 g kg^?1), crude fine (62 g kg^?1) and total carbohydrates (236 g kg^?1). Potassium and calcium were the predominant elements in the poppy seeds. Linoleic acid was the major unsaturated fatty acid (750 g kg^?1 total fatty acids) while palmitic acid was the main saturated one (86-4 g kg^?1). The amounts of α-, β- and δ-tocopherols found in poppy seed oil were 220 μg g^?1, 40 μg g^?1 and 20 μg g^?1 respectively. Among the water-soluble vitamins determined, pantothenic acid was found at the highest level followed by niacin and thiamin.     

Residues of ethoxyquin in poultry tissues and eggs

Tissues of broilers raised experimentally on diets containing the feed antioxidant ethoxyquin (6-ethoxy-2,2,4-trimethyl-1,2-dihydroquinoline) contained very low levels of this compound (<0.005 mg kg^?1) both raw and after roasting. Residues were higher in liver (up to 0.063 mg kg^?1) and highest in what appeared to be the major deposition site, the body fat (0.215 mg kg^?1). The body fat of commercial broiler samples showed much lower levels (0.015-0.051 mg kg^?1). Leg and breast muscles from laying hens after 30 weeks on the experimental diets had low ethoxyquin levels (< 0.005 mg kg^?1) with a higher liver content (0.048 mg kg^?1) and again the highest level in the body fat (0.238 mg kg^?1). Eggs from these hens contained 0.031 mg kg^?1 ethoxyquin, probably all in the yolk. Market samples of eggs from five major producers gave an average value of 0.011 mg kg^?1. A rapid and considerable loss of ethoxyquin occurred in the feed troughs, the concentration dropping from 125 mg kg^?1 to 90 mg kg^?1 in four hours.