Assessment of mercury and cadmium via seafood consumption in Italy: estimated dietary intake (EWI) and target hazard quotient (THQ)

Mercury (Hg) and cadmium (Cd) were quantified in fish, cephalopods and crustaceans from Italian supermarkets. Sample compliance with European dietary standards as well as human health risks according to provisional tolerable weekly intake (PTWI) and the methodology of target hazard quotient (THQ) were evaluated. Both element levels were under European legal limits, except for some fish having Hg and Cd contents exceeding or equal to critical values. Estimated weekly intakes (Hg: fish = 0.07–1.44 µg kg^?1 bw week^–1; cephalopods = 0.05–0.15 µg kg^?1 bw week^–1; crustaceans = 0.04–0.08 µg kg^?1 bw week^–1; and Cd: fish = 0.04–0.32 µg kg^?1 bw week^–1; cephalopods = 0.07–0.27 µg kg^?1 bw week^–1; crustaceans = 0.05–0.11 µg kg^?1 bw week^–1) as well as THQ < 1 were within safe limits. Although there seems to be no important risks associated with seafood consumption, Hg exposure was in some cases close to safety margins and thus levels of this metal should be under frequent surveillance.     

Mercury and methylmercury intake estimation due to seafood products for the Catalonian population (Spain)

This study estimates mercury and methylmercury levels in fish and fishery products commercialized in the city of Barcelona, Spain, from 2001 to 2007. Combining data of mercury levels in food with the consumption data of 2158 people (as the median of two 24-h recall), the total mercury intake of the Catalonian population was calculated. Mercury was detected in 32.8% of analysed samples. The general population average weekly intake of total mercury in the Catalonian population was 0.783 µg kg^–1 of body weight. This value is clearly lower than the Joint FAO/WHO Expert Committee on Food Additives (JECFA) provisional tolerable weekly intakes (PTWI) of 5 µg kg^–1 of body weight. The fish group was the main contributor to this value, mainly due to predatory species.     

Dietary exposure of Hong Kong secondary school students to total mercury and methylmercury from fish intake

Fish is the main source of dietary exposure to methylmercury (MeHg), which is a public health concern owing to its potential neurotoxicity. To evaluate the public health risk, this study estimated the total mercury (tHg) and MeHg exposure from fish intake in Hong Kong secondary school students. Median tHg and MeHg concentrations of 280 samples purchased from different commercial outlets (covering 89 species of whole fish and three types of canned tuna), together with the local food consumption data of secondary school students obtained by semi-quantitative food frequency questionnaire in 2000, were used to estimate dietary exposure from fish intake for the average and high consumer (95th percentile exposure). For tHg, the median concentration was 63 µg kg^–1 (range 3–1370 µg kg^–1) and estimated exposures ranged 0.5–0.6 µg kg^–1 body weight (bw) week^–1 for an average consumer and 1.6–1.9 µg kg^–1 bw week^–1 for a high consumer. For MeHg, median concentration was 48 µg kg^–1 (range 3–1010 µg kg^–1) and estimated dietary exposures were 0.4–0.5 µg kg^–1 bw week^–1 for an average consumer and 1.2–1.4 µg kg^–1 bw week^–1 for a high consumer. These values are below the respective provisional tolerable weekly intake (PTWI) established by the Joint Food and Agriculture Organization/World Health Organization Expert Committee on Food Additives (JECFA). The health risk is greater for high consumers since MeHg exposures may approach or exceed the PTWI when other dietary sources are taken into account.     

Methylmercury levels in predatory fish species marketed in Canada

Mercury was detected in all analysed samples of swordfish, marlin, shark and tuna purchased from major supermarket outlets and fish retailers in three cities across Canada. Total mercury and methylmercury levels ranged up to 3845 and 2346 ng g^-1, respectively. Swordfish contained the highest levels, followed by shark, fresh/frozen tuna and marlin. Levels in canned tuna were considerably less than the other examined samples. Methylmercury was extracted with toluene from enzymatically hydrolysed samples after the addition of sulphuric acid and potassium bromide. An L-cysteine back-extraction was used to separate the methylmercury from most organic co-extractives. Analysis of methylmercury (as methylmercury bromide) was by gas chromatography with pulsed discharge detection.     

Human exposure to lead,cadmium and mercury through fish and seafood product consumption in Italy: a pilot evaluation

The presence of selected toxic heavy metals, such as cadmium (Cd), lead (Pb) and mercury (Hg), was investigated in fish and seafood products, namely, blue mussel, carpet shell clam, European squid, veined squid, deep-water rose shrimp, red mullet, European seabass, gilthead seabream, Atlantic cod, European hake, Atlantic bluefin tuna and swordfish so as to assess their human exposure through diet. Metals were detected by quadrupole inductively coupled plasma mass spectrometry (Q-ICP-MS) and hydride generation atomic absorption spectrometry (Hg-AAS). Measurements of Cd, Pb and Hg were performed by means of analytical methods validated in compliance with UNI CEI EN ISO/IEC 17025 [2005. General requirements for the competence of testing and calibration laboratories. Milano (Italy): UNI Ente Nazionale Italiano di Unificazione]. The exposure assessment was undertaken matching the levels of Cd, Pb and total Hg with consumption data related to fish and seafood products selected for this purpose. In order to establish human health implications, the estimated weekly intakes (EWIs) for Cd, Pb and Hg were compared with the standard tolerable weekly intakes (TWI) for Cd and provisional tolerable weekly intakes (PTWIs) for Pb and Hg stipulated by the European Food Safety Authority (EFSA) and the Food and Agriculture Organization/World Health Organization (FAO/WHO) Joint Expert Committee on Food Additives (JECFA). The found metal concentrations were largely below the maximum levels (MLs) established at the European Union level with the exception of Cd. This metal exceeded the MLs in squid, red mullet, European hake and Atlantic cod. Squid and blue mussel showed the highest Pb concentrations which accounted for 60% and 10% of the MLs, respectively. Highest Hg levels were found in predatory fish. The concentrations of Hg in swordfish, Atlantic bluefin tuna and red mullet accounted for 50%, 30% and 30% of the MLs, respectively. The EWIs for Cd, Pb and Hg related to the consumption of fish and seafood products by the median of the Italian total population accounted for 20%, 1.5% and 10% of the standard TWI for Cd as well as PTWIs for Pb and Hg, respectively. Furthermore, the EWIs estimated using consumption data concerning Italian consumers did not exceed the standard TWI and PTWIs, except for Cd at 95th percentile.     

Survey of total mercury and methylmercury levels in edible fish from the Adriatic Sea

Total mercury and methylmercury concentrations were measured in the muscle tissue of different fish species from the Adriatic Sea to ascertain whether the concentrations exceeded the maximum level fixed by the European Commission. Large species-dependent variability was observed. The highest total mercury mean concentrations were in benthic (0.20-0.76 μg g^-1 wet wt) and demersal fish (0.22-0.73 μg g^-1 wet wt), while pelagic species showed the lowest levels (0.09-0.23 μg g^-1 wet wt). In 15% of frost fish, in 42% of skate and in 30% of angler fish samples total mercury concentrations exceeded the maximum level fixed by the European Commission (Hg = 1 μg g^-1 wet wt); for the species for which the maximum level was set to 0.5 μg g^-1 wet wt, concentrations exceeding the prescribed legal limit were observed in 6.4% of bokkem, in 6.6% of pandora, in 20% of megrin, in 12.5% of four-spotted megrim, in 16% of striped mullet, in 5.0% of forkbeard and in 5.3% of picarel samples. In all the different species, mercury was present almost completely in the methylated form, with mean percentages between 70 and 100%. Weekly intake was estimated and compared with the provisional tolerable weekly intake recommended by the FAO/WHO Expert Committee on Food Additives. A high exposure was associated with the consumption of only skates, frost fish and angler fish, thought the consumption of the other species, such as, megrim, four spotted megrim, red fish striped mullet and forkbeard, resulted in a weekly intake slightly below the established provisional tolerable weekly intake.     

Mercury,lead, arsenic,and cadmium in Norwegian seafood products and consumer exposure

ABSTRACT

Seafood can be a source of contaminants, which may raise health concerns. The aim of this study was to analyse the levels of inorganic contaminants in commercially available seafood products and assess consumer exposure. Commercially available samples were collected from 2015–2018 and analysed as composite samples for mercury, lead, arsenic, and cadmium, using accredited methods. Levels of cadmium, lead, and arsenic were low and human exposure of these metals would be minimal from consumption of the analysed seafood products. Mercury levels were well below the EU maximum limit for mercury in fish. However, children, who are high consumers, might be at risk of exceeding the tolerable weekly intake for methyl mercury, when eating products with the highest mercury levels. The collected data can be used for future risk-benefit assessments as intake of processed seafood products represent a large proportion of the populations' seafood intake in Europe.     

湿法消解-原子荧光光谱法同时检测海产品中的总砷与总汞

目的建立湿法消解-原子荧光光谱法同时测定海产品中总砷、总汞含量的分析方法。方法采取硝酸、高氯酸和硫酸混合体系的冷消解及热消解结合的方法,并采用电炉高温短时间加热的优化条件进行消解样品,利用氢化物原子荧光光谱法同时进行总砷、总汞的测定。结果砷在0～40μg/L浓度范围内呈良好线性关系,汞在0～12μg/L浓度范围内呈良好线性关系,相关系数均大于0.999。砷的检出限为0.037μg/L,回收率为94.36%～96.62%,精密度为0.86%～1.36%,汞的检出限为0.048μg/L,回收率为93.33%～95.28%,精密度为0.88%～2.62%。通过对能力验证HMRL1601海鱼粉中总汞、总砷的检测,检测结果总汞为0.30 mg/kg,总砷为2.06 mg/kg,均为满意结果,黄鱼、紫菜质控样的检测值均在参考值允许范围内。结论该方法操作简便、准确灵敏,适用于每一个实验室开展海产品中总砷总汞的同时测定。     

Estimate of mercury and methyl mercury intake associated with fish consumption from Sagua la Grande River,Cuba

This paper provides an estimate of the weekly intake of total mercury (THg) and methyl mercury (MeHg) from consumption of fish from the Sagua la Grande River, Villa Clara, Cuba, by determining the THg levels in different fish species. The levels varied between 0.143 and 0.484 μg g^?1 on a fresh weight basis. None of the analysed fish was found to have levels above the national and international regulatory levels, although THg levels over 0.2 μg g^?1, the threshold concentration established by the World Health Organization (WHO) for the consumption by vulnerable population groups, were found in 75% of samples. The MeHg level was found to be 84% of the THg content. A Food Frequency Survey was given to 127 townspeople to estimate river fish consumption. The weekly intake of MeHg was found to be greater than the value established by the provisional tolerable weekly intake (PTWI) in 50% of children, in 80% of pregnant women, and in 75% of women in childbearing age. These weekly intakes can represent an important risk to the population's health, especially for vulnerable groups.     

Determination of methylmercury in marine fish from coastal areas of Zhejiang,China

The concentration of methylmercury (MMC) and total mercury (TMC) in marine fishes (five species) frequently consumed in the coastal areas of Zhejiang province, China, was determined. The method of high-performance liquid chromatography–atomic fluorescence spectrometry (HPLC-AFS) with the microwave-assisted extraction was used for the MMC determination. TMC was analysed by a direct mercury analyser. MMC and TMC concentrations in five fish species ranged from 53 to 158?µg?kg^?1 and 60 to 172?µg?kg^?1, respectively. The proportion of MMC levels in TMC was greater than 80%. The highest MMC and TMC levels were found in Hairtail.     

The use of molecular markers in the verification of fish and seafood authenticity and the detection of adulteration

The verification of authenticity and detection of food mislabeling are elements that have been of high importance for centuries. During the last few decades there has been an increasing consumer demand for the verification of food identity and the implementation of stricter controls around these matters. Fish and seafood are among the most easily adulterated foodstuffs mainly due to the significant alterations of the species' morphological characteristics that occur during the different types of processing, which render the visual identification of the animals impossible. Even simple processes, such as filleting remove very important morphological elements and suffice to prevent the visual identification of species in marketed products. Novel techniques have therefore been developed that allow identification of species, the differentiation between species and also the differentiation of individuals that belong to the same species but grow in different populations and regions. Molecular markers have been used during the last few decades to fulfill this purpose and several improvements have been implemented rendering their use applicable to a commercial scale. The reliability, accuracy, reproducibility, and time-and cost-effectiveness of these techniques allowed them to be established as routine methods in the industry and research institutes. This review article aims at presenting the most important molecular markers used for the authentication of fish and seafood. The most important techniques are described, and the results of numerous studies are outlined and discussed, allowing interested parties to easily access and compare information about several techniques and fish/seafood species.     

Fumonisins B1 and B2 in the corn-milling process and corn-based products,and evaluation of estimated daily intake

The distribution of fumonisins (FBs: FB₁ and FB₂) in the corn-milling process and in corn-based products, as well as daily intake estimates for the Brazilian population were evaluated. Among corn fractions samples, corn meal had the highest mean concentration of FB₁ (1305 µg kg^?1) and FB₂ (651 µg kg^?1) and a distribution factors of 452% and 256% in relation to corn grain, respectively. On the other hand, the distribution factor of FB₁ and FB₂ in corn flour was found to be 144% and 88% respectively, which demonstrates that fumonisins in this fraction were reduced compared with corn grain. As a result, almost half the corn meal samples (47%) would be non-compliant with future Brazilian regulation (2017) for fumonisins. However, corn-based products, such as corn flakes and popcorn, were in compliance with the regulation. The average probable daily intake and maximum probable daily intake of fumonisins estimated for the Santa Catarina state (Brazil) population were below the provisional maximum tolerable daily intake of 2 µg kg^?1 body weight day^?1 for all corn samples. Despite this, the adoption of practices to control the occurrence of fumonisins should be applied to the corn-milling fractions that may contain a higher concentration of this toxin, such as corn meal, often used for animal feed in Brazil.     

水产品中生物胺的检测与控制技术研究进展

生物胺是一类低分子量含氮有机化合物,具有脂肪族、芳香族、杂环结构,广泛存在食品尤其是富含蛋白质的水产品中,大多由微生物来源的氨基酸脱羧酶对氨基酸脱羧后形成。水产品风味独特、营养丰富,备受消费者喜爱,生物胺的存在不仅会影响水产品的品质,还会危害人类的健康,引起过敏性反应。根据生物胺的组成可分为单胺、二胺和多胺,根据其挥发难易程度可分为挥发性胺、非挥发性胺,常见的生物胺有组胺、酪胺、腐胺、尸胺、色胺、苯乙胺、三甲胺、二甲胺等。本文重点介绍了水产品中常见生物胺的色谱、波谱、生物检测方法,以及物理、化学、生物控制技术的最新进展,分析了水产品中生物胺研究的发展趋势,以期为水产品的品质监测与安全控制提供理论基础。     

Annual variation of deoxynivalenol in Danish wheat flour 1998-2003 and estimated daily intake by the Danish population

The occurrence of deoxynivalenol (DON) in Danish wheat flour was studied during the period 1998-2003 by either capillary gas chromatography with electron capture detection and liquid chromatography coupled to an ion trap mass spectrophotometer. A total of 151 samples were collected from mills and the retail market in Denmark. Contamination levels varied considerably from year-to-year with the highest concentrations occurring in samples from the 2002 harvest with mean and median concentrations of 255 and 300 µg kg^-1, respectively. Compared to other harvest years, 2002 had the highest amount of precipitation around flowering time, i.e. from the end of June to the beginning of July covering weeks 25-27. The lowest average levels were found in samples from the 2001 harvest, where weeks 25-27 were dry compared with other harvest years. The highest value (705 µg kg^-1) was obtained in a flour sample from the 2002 harvest, but none of the tested samples exceeded the maximum limit of 750 µg kg^-1, which has been recently introduced by the European Commission for DON in flour used as raw materials in food products. Calculation of chronic or usual intake by a deterministic approach showed that intake did not exceed the TDI of 1 µg kg^-1 bw day^-1 either for the whole population or for children. A probabilistic approach also showed that intake in general was below the TDI, but intake for children in the 99% percentile amounted to more than 75% of the TDI. The highest intake is calculated to be 2.5 µg kg^-1 bw day^-1.     

Recent developments in non-thermal processing for seafood and seafood products: cold plasma,pulsed electric field and high hydrostatic pressure

Seafood and seafood products (SSPs) are highly perishable foods due to their chemical composition (high moisture content and nutrients). They are regarded as highly sensitive to different processing technologies. SSPs are subjected to various processing conditions with intent to extend their shelf life, quality and minimal nutritional degradation. Recently developed non-thermal technologies (NTTs) have proved their efficacy in inactivation of microorganisms and enzymatic activities, enhancing the shelf life while maintaining the nutritional quality. Considering the significant impacts of NTTs on shelf life extension and maintaining quality parameters, it has attracted considerable interest by scientific communities and commercial applications in some cases. Thus, this article focuses on recent developments in the application of NTTs namely, cold plasma, pulsed electric field and high hydrostatic pressure as well as advantages and limitations of NTTs. In addition, their impacts on microbiological, physicochemical, quality and safety of SSPs are elucidated.     

Mercury and methylmercury levels in the main traded fish species in Hong Kong

This survey was undertaken to determine the levels of aflatoxins in melon seeds. Among 65 samples analyzed by liquid chromatography (LC), the results showed that aflatoxin B₁ (AFB₁) was the major toxins in melon seeds, detected in 58 samples (89.2% of the total) at an average concentration of 8.5?ng?g^?1. The level of AFB₁ in 12 samples exceeded the maximum tolerated level for AFB₁ in Iranian (5?ng?g^?1) regulations; in other words, 18.5% of samples were unfit for human consumption.     

Polycyclic aromatic hydrocarbons (PAHs) in meat products and estimated PAH intake by children and the general population in Estonia

The concentrations of benzo[a]pyrene and 11 other polycyclic aromatic hydrocarbons (PAHs) were analysed from 322 commercial, cured meat products and 14 home-grilled meat samples as part of the Estonian food safety monitoring programme during 2001-2005. The maximum acceptable concentration of 5 µg kg^-1 for benzo[a]pyrene was exceeded in 3.4% of samples. The highest PAH concentrations were detected in home-grilled pork samples. Using of disposable grilling unit resulted in 1.6 times higher PAH concentrations compared to the traditional wood-burning grill. The average intake of benzo[a]pyrene and sum of 12 PAHs from meat products was estimated for children (age 1-16 years) on the basis of an individual food consumption questionnaire and, for the general population, based on national food consumption data. The highest total PAH concentrations detected were 16 µg kg^-1 in smoked meat and ham, 19 µg kg^-1 in smoked sausage and 6.5 µg kg^-1 in smoked chicken samples. Since smoking and grilling are prevalent meat-cooking methods in Estonia, the impact of meat products is assessed to be significant in overall PAH intake.     

Biogenic amines in fish,fish products and shellfish: a review

Fish, cephalopods and shellfish provide a healthy source of high-quality proteins, essential vitamins, minerals and polyunsaturated fatty acids. The beneficial effects of fish consumption on human health such as protection against coronary heart disease and certain cancer may be offset by fish decomposition and the formation of chemical contaminants such as biogenic amines. There are several toxicological effects of biogenic amines on humans, especially histamine. It is the causative agent of histamine or scombroid fish poisoning which is a significant public health problem. In individuals with diminished histamine detoxification, ingestion of even a low or moderate histamine- or tyramine-containing fish may lead to food intolerance. Biogenic amines such as putrescine, tyramine and cadaverine can potentiate histamine toxicity. Furthermore, dietary polyamine intake should be minimised in some cancer patients. Besides their potential toxicity, biogenic amines are used for the evaluation of hygienic quality of different marine and freshwater species. Spoilage pattern and biogenic amine formation are species specific. Histamine has been traditionally used as an indicator of the quality of histidine-rich fish (dark-muscle fish). On the other hand, putrescine and cadaverine are the most objective indicators of quality of histidine-poor fish (white-muscle fish), shellfish and fermented seafood products.     

Recent advancements in the application of non-thermal plasma technology for the seafood industry

Abstract

Non-thermal plasma (NTP) is one of the most promising minimal processing methods for the food industry. However up until recently there are limited studies which would report the application and effect of NTP on processed seafood. The objective of this review is to highlight the recent findings and advancements in the application of NTP within the fish and other seafood industry, including direct application of fresh and dried fish and seafood with as well as indirect application of plasma activated water and seafood industry wastewater purification. The article also summarizes the effect of plasma treatment on microbiological quality, physicochemical and sensory properties and oxidation rate of treated fish and seafood. NTP has high potential to be used within various fields of seafood industry. It is especially effective in treatment of dried seafood products, but the use of plasma activated water during various processing steps such as seafood washing could be also beneficial. Moreover NTP could also be used as a cost effective and environmentally friendly method for seafood wastewater purification.     

浙江沿海海产品甲基汞污染调查及膳食风险评估

运用高效液相色谱-原子荧光联用法研究海产品肌肉中汞形态分布特征,调查了浙江沿海50 个品种共计891 个样本中甲基汞含量,并结合浙江省居民水产品消费量,对海产品甲基汞污染食用风险进行了评估。结果显示：94.2%的海产品均有甲基汞检出,甲基汞是海产品肌肉中汞元素的主要存在形态,其含量占总汞质量分数65.0%～95.2%,所有样品甲基汞含量范围为0～0.95 mg/kg,均低于国家标准限量值;不同鱼类甲基汞含量存在差异,营养级别高的鱼类对甲基汞的生物富集能力较强,鲨鱼、金枪鱼等大型肉食性鱼类甲基汞含量明显高于一般鱼类,存在超标可能性;风险评估表明,浙江沿海一般海产品甲基汞污染食用风险较低,但长期或大量食用金枪鱼和鲨鱼等甲基汞污染较高的海产品,存在健康风险。