Trace elements inThunnus thynnusfrom Mediterranean Sea and benefit–risk assessment for consumers

P. Oliveira MB, Prieto MA. Health benefits of bluefin tuna consumption: (Thunnus thynnus) as a case study

Consumers are increasingly interested in food products with high nutritional value and health benefits. For instance, fish consumption is linked with diverse positive health benefits and the prevention of certain widespread disorders, such as obesity, metabolic syndrome, or cardiovascular diseases. These benefits have been attributed to its excellent nutritional value (large amounts of high-quality fatty acids, proteins, vitamins, and minerals) and bioactive compounds, while being relatively low-caloric. Atlantic bluefin tuna (Thunnus tynnus) is one of the most consumed species worldwide, motivated by its good nutritional and organoleptic characteristics. Recently, some organizations have proposed limitations on its consumption due to the presence of contaminants, mainly heavy metals such as mercury. However, several studies have reported that most specimens hold lower levels of contaminants than the established limits and that their richness in selenium effectively limits the contaminants' bioaccessibility in the human body. Considering this situation, this study aims to provide baseline data about the nutritional composition and the latest evidence regarding the beneficial effects of Atlantic bluefin tuna consumption. A review of the risk-benefit ratio was also conducted to evaluate the safety of its consumption, considering the current suggested limitations to this species' consumption.

Risk Assessment of Essential and Toxic Elements in Freshwater Fish Species from Lakes near Black Sea, Bulgaria

The aims of this study were to measure the concentrations of selected toxic and essential elements in the muscle tissue of five common freshwater fish species ((roach (Rutilus rutilus), freshwater bream (Abramis brama), prussian carp (Carassius gibelio), crucian carp (Carassius carassius) and common carp (Cyprinus carpio)) from Lake Burgas and Lake Mandra (Bulgaria). In all samples the levels of Cd, Cr, Cu, Mn, Ni, Pb, Fe and Zn were under the maximum allowed concentrations for safe human consumption in Bulgaria and ranged as follows: Cd 0.02-0.05; Cr 0.03-0.06; Cu 0.11-0.20; Mn 0.05-0.71; Ni 0.06-0.11; Pb 0.15-0.27, Fe 1.68-5.86 and Zn 1.94-9.06 mg/kg wet weight. The concentration of As was under detection limit. An assessment of the human risk by calculation of the target hazard quotients (THQ), hazard index (HI) and target risk (TR) was performed. The target hazard quotient (THQ) for individual elements and HI for combined metals were lower than 1, indicating no health risk for consumers due to the intake of either individual or combined metals. The target risk for iAs, Pb and Ni was below 10^-6, indicating no carcinogenic risk. According to these results, the consumption of these freshwater fish species is safe for human health.

Valorization of Traditional Alcoholic Beverages: The Study of the Sicilian Amarena Wine during Bottle Aging

Traditional alcoholic beverages have always been part of the Mediterranean culture and, lately, they have been re-evaluated to valorize both the territory and local customs. In this study, the Amarena wine, a fortified wine included in the national list of the traditional agri-food products, was characterized during bottle aging for oenological parameters, chromaticity, volatiles, and inorganic elements. Then, experimental data were visually interpreted by a principal component analysis (PCA). PCA revealed that most of oenological parameters (i.e., alcoholic grade, total dry extract, sugars, organic acids, and phenolic compounds) had a scarce discriminating power. Additionally, ethyl esters were only present in younger products, while remaining at quite constant levels. Conversely, certain metals (i.e., Mg, Na, Mn, Zn, and Cu), chromatic properties, and pH differentiated older Amarena bottles from the younger counterpart. Particularly, acetaldehyde and furanic compounds proved to be valid aging markers. A sensorial analysis highlighted that fruity and floral odors and flavors characterized younger beverages, while dried fruity, nutty, and spicy notes were displayed by older products, along with the valuable attribute of “oxidized” typically observed in aged Sherry wines. Overall, this study may encourage the production and commercialization of the Amarena wine, thus preserving the cultural heritage of the Mediterranean area.

Histological and Chemical Analysis of Heavy Metals in Kidney and Gills of Boops boops: Melanomacrophages Centers and Rodlet Cells as Environmental Biomarkers

Industrialization has resulted in a massive increase in garbage output, which is frequently discharged or stored in waterways like rivers and seas. Due to their toxicity, durability, bioaccumulation, and biomagnification, heavy metals (such as mercury, cadmium, and lead) have been identified as strong biological poisons. Their presence in the aquatic environment has the potential to affect water quality parameters and aquatic life in general. Teleosts’ histopathology provides a sensitive indicator of pollutant-induced stress, because their organs have a central role in the transformation of different active chemical compounds in the aquatic environment. In particular, the gills, kidneys, and liver are placed at the center of toxicological studies. The purpose of this study is to examine the morphological changes caused by heavy metals in the kidney and gills of Boops boops, with a focus on melanomacrophages centers (MMCs) and rodlet cells (RCs) as environmental biomarkers, using histological and histochemical stainings (hematoxylin/eosin, Van Gieson trichrome, Periodic Acid Schiff reaction, and Alcian Blue/PAS 2.5), and immunoperoxidase methods. Our findings show an increase of MMCs and RCs linked to higher exposure to heavy metals, confirming the role of these aggregates and cells as reliable biomarkers of potential aquatic environmental changes reflected in fish fauna. The cytological study of RCs and MMCs could be important in gaining a better understanding of the complicated immune systems of teleosts.

Tissue Distribution of Mercury and Its Relationship with Selenium in Atlantic Bluefin Tuna (Thunnus thynnus L.)

Mercury (Hg) is an important heavy metal to consider in marine predators, while selenium (Se) has a natural antagonistic effect on this metal in fish. The Atlantic bluefin tuna (ABFT, Thunnus thynnus) is a pelagic top-level predator of the trophic web and their Hg muscular content is an object of concern in food safety. Nevertheless, little is known about levels of this metal in remaining tissues, which may be important as by-product source, and its relationship with Se. Thus, concentration of both elements in liver, kidney, brain, gill and bone, in addition to muscle, of ABFT were determined. The kidney was the tissue with the highest concentration of Hg (Total-Hg, THg) and Se, and the Se/THg concentration ratio was similar in all tissues, except bone and muscle. The Selenium Health Benefit Value (HBV_Se) was positive in each specimen and tissue, indicating that the Se plays an important role against Hg not only in the muscle.

Mercury and selenium levels in archive samples of wild Atlantic bluefin tuna from the Mediterranean Sea

This study examined total mercury (THg) and selenium (Se) levels in archive samples (white and red muscles, liver, gills) of the wild Atlantic bluefin tuna (ABFT) (Thunnus thynnus) (n = 18) captured in the central Adriatic Sea. The influence of fish size, age, and tissue type on element distribution was examined. There were significant differences in THg and Se levels, and Se:THg molar ratios among tissues. THg levels were highest in liver and lowest in gills (liver > red muscle > white muscle > gills), while Se levels were also highest in liver but lowest in white muscle (liver > red muscle > gills > white muscle). Se:THg molar ratios were highest in gills (22-82), intermediate in liver (11-29) and red muscle (7-36), and lowest in white muscle (1.7-7.6). Concentrations of THg in all tissues and Se in liver and caudal muscle were positively correlated with tuna age and size, while the Se:THg molar ratio in gills and all white muscles was negatively correlated with tuna age and size, indicating that the protective role of Se against THg is reduced in older specimens. The selenium health benefit values (HBV_Se) were above zero in all tissues, indicating a small excess of Se after Hg sequestration. However, since the obtained HBV_Se for edible tissues were near zero (0.01-0.04), and more than 70% of white muscle samples and all red muscle samples exceeded the EU regulatory limit for THg in fish muscle, it would be advisable to limit their intake in adults to one meal per month.

Lipid-free tuna muscle samples are suitable for total mercury analysis

Tropical tunas are largely consumed worldwide, providing major nutritional benefits to humans, but also representing the main exposure to methylmercury, a potent neurotoxin that biomagnifies along food webs. The combination of ecological tracers (nitrogen and carbon stable isotopes, δ¹⁵N and δ¹³C) to mercury concentrations in tunas is scarce yet crucial to better characterize the influence of tuna foraging ecology on mercury exposure and bioaccumulation. Given the difficulties to get modern and historical tuna samples, analyses have to be done on available and unique samples. However, δ¹³C values are often analysed on lipid-free samples to avoid bias related to lipid content. While lipid extraction with non-polar solvents is known to have no effect on δ¹⁵N values, its impact on mercury concentrations is still unclear. We used white muscle tissues of three tropical tuna species to evaluate the efficiency and repeatability of different lipid extraction protocols commonly used in δ¹³C and δ¹⁵N analysis. Dichloromethane was more efficient than cyclohexane in extracting lipids in tuna muscle, while the automated method appeared more efficient but as repeatable as the manual method. Lipid extraction with dichloromethane had no effect on mercury concentrations. This may result from i) the affinity of methylmercury to proteins in tuna flesh, ii) the low lipid content in tropical tuna muscle samples, and iii) the non-polar nature of dichloromethane. Our study suggests that lipid-free samples, usually prepared for tropical tuna foraging ecology research, can be used equivalently to bulk samples to document in parallel mercury concentrations at a global scale.

Characterization of classes of mollusks in the East Atlantic according to their element content

One hundred and ninety-two samples from six species of mollusks classified into the following taxonomic classes: Gastropoda (Patella aspera, Patella candei crenata), Bivalvia (Mytilus galloprovincialis, Ensis directus), and Cephalopoda (Abraliposis morisii, Pyroteuthis margatifera) were investigated. Samples were collected in the Atlantic Ocean (Canary Islands and Galicia). The concentrations of Al, B, Ba, Ca, Cd, Co, Cr, Cu, Fe, K, Li, Mg, Mn, Mo, Na, Ni, Pb, Sr, V, and Zn were determined by ICP-OES. Statistical analysis verified that the classes of benthic organisms had the highest concentration of elements. However, the Cephalopoda class had the highest Cd (1.685 ± 0.929 mg/kg) and Pb (0.826 ± 1.104 mg/kg) content. On the other hand, the values obtained in this study were compared with studies conducted in other parts of the world to verify the environmental state of the Atlantic Ocean using the organisms studied as bioindicators.

Human health risk-benefit assessment of fish and other seafood: a scoping review

Fish and other seafood are important sources of nutrients, but they are also sources of chemical contaminants that may cause adverse health effects. This article aimed to identify existing risk-benefit assessments (RBA) of fish, shellfish, and other seafood, compare methodologies, discuss differences and commonalities in findings, and identify limitations and ways forward for future studies. We conducted a scoping review of the scientific literature of studies in all languages published from 2000 through April 2019. We identified 106 RBA of fish and other seafood across Europe, Asia, North America, Africa, and at the global level. Studies were heterogeneous in terms of types of fish and other seafood considered, beneficial and adverse compounds assessed, and overall methodology. Collected data showed that a diet consisting of a variety of lean and fatty fish and other seafood is recommended for the overall population and that women of childbearing age and children should limit the consumption of fish and other seafood types that have a high likelihood of contamination. Our review emphasizes the need for evidence-based, up-to-date, and harmonized approaches in RBA in general.

Discrimination of Tunisian Honey by Mineral and Trace Element Chemometrics Profiling

The concentrations of 19 chemical elements have been determined in 36 honey samples of different botanical (wildflower, eucalyptus, eucalyptus red flowers, prickly pears, lemon blossom, thyme, almond, rosemary and jujube) honeys from the three geographical areas of Tunisia (Sidi Bouzid, Nabeul and Sfax) using inductively coupled plasma mass spectrometry (ICP-MS). The aim of this work was to use the multielement analysis together with chemometric tools to verify the botanical and the geographical origin of honeys. The correlation on the basis of mineral element content between the honey samples and their botanical and/or geographical origins was in some measure achieved. The data collected on the samples were also used to evaluate the nutritional quality and the potential health risks associated with elements via consumption of the Tunisian honey. According to the results obtained, the intake of essential elements was small, and the potential health risks associated with toxic or potentially toxic elements via consumption of this food were overall insignificant.

Oceanic karma? Eco-ethical gaps in African EEE metal cycle may hit back through seafood contamination

The increasing global demand for electric and electronic equipment (EEE) such as smartphones, tablets and electric car batteries has resulted in an increase in heavy metal releases to the environment at different steps during its manufacture (e.g. mining, extraction, production and e-waste). Some critical raw materials (CRMs) that supply the worldwide demand of technology are mainly sourced from Africa, but their resulting heavy metal pollution can reach citizens from other regions of the world through seafood caught in African waters, which would act as a vector. In this study, we review heavy metal contents in African fish and, as proof of concept, we analyse heavy metal content in three tuna species (Thunnus alalunga, T. albacares and T. obesus) caught in different regions inside the Sustainable Fisheries Partnership Agreements (SFPAs) by Spanish fleets and commercialised in Spain. Thunnus alalunga and T. albacares from African waters had higher concentrations of heavy metals (especially Hg but also As and Pb) in muscle than samples of the same species caught in other waters. Metal profiles in tunas from African waters were significantly correlated with those of continental and coastal fish from nearby areas impacted by mines and e-waste, as found in the literature review. Based on these results we identify research priorities that should be addressed in order to improve the social and environmental sustainability of EEE metal manufacture in Africa.

Stable mercury concentrations of tropical tuna in the south western Pacific ocean: An 18-year monitoring study

Global anthropogenic mercury (Hg) emissions to the atmosphere since industrialization are widely considered to be responsible for a significant increase in surface ocean Hg concentrations. Still unclear is how those inputs are converted into toxic methylmercury (MeHg) then transferred and biomagnified in oceanic food webs. We used a unique long-term and continuous dataset to explore the temporal Hg trend and variability of three tropical tuna species (yellowfin, bigeye, and skipjack) from the southwestern Pacific Ocean between 2001 and 2018 (n = 590). Temporal trends of muscle nitrogen (δ¹⁵N) and carbon (δ¹³C) stable isotope ratios, amino acid (AA) δ¹⁵N values and oceanographic variables were also investigated to examine the potential influence of trophic, biogeochemical and physical processes on the temporal variability of tuna Hg concentrations. For the three species, we detected significant inter-annual variability but no significant long-term trend for Hg concentrations. Inter-annual variability was related to the variability in tuna sampled lengths among years and to tuna muscle δ¹⁵N and δ¹³C values. Complementary AA- and model-estimated phytoplankton δ¹⁵N values suggested the influence of baseline processes with enhanced tuna Hg concentrations observed when dinitrogen fixers prevail, possibly fuelling baseline Hg methylation and/or MeHg bioavailability at the base of the food web. Our results show that MeHg trends in top predators do not necessary capture the increasing Hg concentrations in surface waters suspected at the global oceanic scale due to the complex and variable processes governing Hg deposition, methylation, bioavailability and biomagnification. This illustrates the need for long-term standardized monitoring programs of marine biota worldwide.

Proximal Composition and Nutritive Value of Raw, Smoked and Pickled Freshwater Fish

The aim of the study was to assess protein, fat, salt, collagen, moisture content and energy value of freshwater fish purchased in Polish fish farms. Eight species of freshwater fish (raw, smoked, pickled) were assessed by near infrared spectroscopy (NIRS). The protein content varied between 15.9 and 21.7 g/100 g, 12.8 and 26.2 g/100 g, 11.5 and 21.9 g/100 g in raw, smoked and pickled fish, respectively. Fat content ranged from 0.89 to 22.3 g/100 g, 0.72 to 43.1 g/100 g, 0.01 to 29.7 g/100 g in raw, smoked and pickled fish, respectively. Salt content ranged from 0.73 to 1.48 g/100 g, 0.77 to 3.39 g/100 g, 1.47 to 2.29 g/100 g in raw, smoked and pickled fish, respectively. A serving (150 g) of each fish product provided 53.2–71.9% of the Reference Intake (RI) for protein, 2.21–60.3% of the RI for fat, 21.3–61.3% of the RI for salt and 6.27–24.4% kJ/6.29–24.5% kcal of the RI for energy. Smoked fish had a higher protein and also fat content than raw and pickled fish, while smoked and pickled fish had higher salt content than raw fish. Cluster analysis was performed, which allowed to distinguish, on the basis of protein, fat, salt, collagen and moisture content, mainly European eel.

Geographical origin differentiation of Chinese Angelica by specific metal element fingerprinting and risk assessment

Traceability offers significant information about the quality and safety of Chinese Angelica, a medicine and food homologous substance. In this study, a systematic four-step strategy, including sample collection, specific metal element fingerprinting, multivariate statistical analysis, and benefit-risk assessment, was developed for the first time to identify Chinese Angelica based on geographical origins. Fifteen metals in fifty-six Chinese Angelica samples originated from three provinces were analyzed. The multivariate statistical analysis model established, involving hierarchical cluster analysis (HCA), principal component analysis (PCA), and self-organizing map clustering analysis was able to identify the origins of samples. Furthermore, benefit-risk assessment models were created by combinational calculation of chemical daily intake (CDI), hazard index (HI), and cancer risk (CR) levels to evaluate the potential risks of Chinese Angelica using as traditional Chinese medicine (TCM) and food, respectively. Our systematic strategy was well convinced to accurately and effectively differentiate Chinese Angelica based on geographical origins.

Zn, Cu, and Fe Concentrations in Dehydrated Herbs (Thyme, Rosemary, Cloves, Oregano, and Basil) and the Correlation with the Microbial Counts of Listeria monocytogenes and Other Foodborne Pathogens

Zn, Cu, and Fe concentrations were measured in dehydrated herbs (thyme, rosemary, cloves, oregano, and basil) marketed in bulk or packaged in glass or polyethylene terephthalate (PET). Microbial counts of Listeria monocytogenes and other five foodborne pathogens were also checked when herbs were previously added to the growing media. The highest mean concentrations were found in basil for Zn and Cu, and in thyme and basil for Fe; the lowest ones for these minerals were in cloves (p < 0.05). Basil had significantly higher microbial counts in five of the six foodborne pathogens studied (p < 0.05). Cloves have the best hygienic quality as there is no microbial growth of L. monocytogenes, Clostridium perfringens, and Bacillus cereus; they therefore could be used as a natural preservative in food. Aromatic herbs marketed in bulk showed a significantly higher microbial count (p < 0.05). Zn, Cu, and Fe concentrations were positively correlated with microbial growth for L. monocytogenes, C. perfringens, B. cereus, and psychrophilic microorganisms (p < 0.05), so they could act as a growing factor for the foodborne pathogens.

Bioaccumulation of Mineral Elements in Different Biological Substrates of Athletic Horse from Messina, Italy

The objective of this study was to evaluate the levels and the potential bioaccumulation of vanadium (V), chromium (Cr), cobalt (Co), copper (Cu), zinc (Zn), cadmium (Cd), lead (Pb), and bismuth (Bi) in horses from the industrial risk area of Sicily (Italy). Different biological substrates (whole blood, serum; tail and mane) and samples of hay, concentrate and water provided to the horses were processed by means of Thermo Scientific iCAP-Q ICP-MS spectrometer for mineral concentration. One-way analysis of variance (ANOVA) was applied to show the differences in various trace elements in the biological substrates. Pearson's test was applied to evaluate the correlation of mineral concentrations between whole blood and serum; and tail and mane. The results showed statistical differences of tested mineral elements among biological substrates; Cr whole blood concentrations were negatively correlated with serum concentrations and a positive correlation between whole blood and serum was observed for Cd and Bi. This latter also showed a positive correlation between mane and tail. The concentrations of V, Cr, and Pb in tail with serum and whole blood samples were negatively correlated, while the concentrations of Cd in tail and serum samples were positively correlated. Minerals had a non-homogenous distribution in the organism, showing different concentrations in the biological substrates.

Potentially Toxic Elements in Xiphias gladius from Mediterranean Sea and risks related to human consumption

Swordfish is a widely consumed fish worldwide. The aim of this work was to evaluate levels of As, Zn, Mn, Fe, Cu, Al, Cr, Ni, Se, Cd, Pd and Hg in 28 samples of swordfish muscles, coming from zone of Food and Agriculture Organization (FAO) namely 37.1 and 37.2, in order to assess potential public health risks. 100% of the samples had Cd levels not detectable, 32.14% of samples exceeded European maximum limits set for Hg. Health risk assessment showed a not dangerous condition for Al (0.65% of Tolerable Weekly Intake), Ni (0.27% of Tolerable Daily Intake) and Pb (0.68% of Provisional Tolerable Weekly Intake), but very hazardous states for Hg (159.69% of Tolerable Weekly Intake) and As (1099.45% for minimum value of Benchmark Dose Limit). Target Hazard Quotient (THQ) showed dangerous values only for As and Hg. Analytical data of the present study suggest a swordfish prudent consumption.

Zinc, aluminium, tin and Bis-phenol a in canned tuna fish commercialized in Lebanon and its human health risk assessment

One of the drawbacks of canning is the migration of various chemicals from the package into the food product. This work aimed at analyzing the concentrations of Bisphenol A (in 137 samples) and heavy metals (in 51 samples) of canned tuna commercialized in Lebanon while evaluating the variability across different brands, packing media, layer, and proximity to the expiry date. Accordingly, BPA was detected in 12 samples out of the 137 samples, run in duplicates. The estimated daily intake of BPA for the selected samples (n = 274) was lower than the tolerable daily intake of BPA, 0.004 mg/kg/day. Therefore, there is no health risk associated with BPA as a result of consuming canned tuna commercialized in the Lebanese market. Besides, the study has shown that 66 samples out of 102 were contaminated with Zn whereas 100% of the samples were contaminated with Aluminum and Tin. However, the calculated Health Risk Index of all the considered heavy metals are all within the safe limits as defined by EFSA (European Food Safety Authority) and Codex Alimentarius.

Mineral content and physico-chemical parameters of honey from North regions of Algeria

Honey is accepted as food and medicine by all generations both ancient and modern. In this study the concentrations of K, Mg, Na, Zn, Fe, Mn, Cu, Cr, Ni, Se, As, Pb, Cd, Sb, Ti, V, Co, Hg and the determination of some physico-chemical parameters in 29 multifloral honeys collected from different North regions of Algeria: Algiers, Bouria, Ghardaïa, Laghouat, M'sila, Naâma, Tlemcen and El Bayadth during year 2018 were carried out. All minerals were determined by ICP-OES/MS and Hg by DMA-80. The most abundant minerals decreased in the following order: K, Na, Mg, Fe, Zn. Lead content exceeded the Codex Alimentarius and the European Union in all honey samples analysed, Cd and As levels were lower than the limits fixed by the European legislation and the regulations of the Codex Alimentarius. The Recommended Dietary Allowance values and benchmark levels were employed to assess the honey quality and safety.

Major, minor and trace element concentrations in spices and aromatic herbs from Sicily (Italy) and Mahdia (Tunisia) by ICP-MS and multivariate analysis

Element contents in different types of spices and aromatic herbs collected from Italy and Tunisia were evaluated. The aim was to evaluate: the possible differences and/or similarities among the analyzed samples; if it is possible related the samples to their geographical origins; the nutritional quality and the potential health risks. Potassium, Ca, Mg and Ni were low in laurel and rosemary; mint and thyme showed the highest Na and the lowest Se contents; arsenic and Cd levels were found highest in verbena which had also the lowest Hg content; lastly, black pepper had the highest Mn and the lowest Pb contents. Instead discrimination between Italian and Tunisian samples for each spices and aromatic herbs under analysis was achieved by PCA. Essential elements intake through samples was small. Levels of Pb in some samples exceed the maximum allowable level, but any safety risk for consumers is excluded.

Blood Response to Mercury Exposure in Athletic Horse From Messina, Italy

Mercury (Hg) exists in various chemical forms, and it is different to health effects. The most toxic effects occur in the central nervous system during fetal development with irreversible alterations of the nerve cells of the cerebral cortex and, it is essential to monitor the tissue residues of Hg to protect the animal's health. The present investigation was carried out during May 2019 in 20 horses located in equine sport center near the area of Milazzo, Messina, that is a part of Sicilian territory heavily polluted by many toxic substances. The purpose of this study was to determine the concentration of Hg in blood, serum, food, and water administered to horses and from the hematological profile as a biomarker of blood in relation to the bioaccumulation of Hg. The hematologic parameters (red blood cell, white blood cell, hemoglobin concentration, hematocrit, mean corpuscular volume, mean corpuscular hemoglobin, mean corpuscular hemoglobin concentration, and platelets) were processed with an automated hematology analyzer, and Hg concentrations were determined by DMA-80. To carry out the variation in the Hg levels in serum and blood, the data were subjected to paired t-test analysis; post-hoc comparisons were performed using Tukey's test. The differences were considered statistically significant when P < .05. Paired t-test showed that in blood samples, Hg concentrations were significantly higher than the serum, and blood samples were positively correlated with serum (r = 0.99; P < .0001). The Hg contents determined in blood, serum, hay, and water samples were below the respective benchmarks, and therefore, we can exclude any toxicological risk for athletic horse.

Inferring trophic groups of fish in the central-east Atlantic from eco-toxicological characterization

The marine organisms are exposed to great human-induced alterations due to the indiscriminate discharges into the sea, which is why the study of marine pollution is of great value for each ecosystem. Each organism bioaccumulates distantly the heavy metals and trace elements in its organism. Because of this it is possible to classify different groups of fish according to their feeding with the content of these metals. Ten fish species were grouped considering their trophic level and habitat ecology (benthic predators, herbivores, omnivores, pelagic predators and superpredator) and analyzed for its metal content. Statistically significant differences were found among all the fish groups, with the Superpredator group containing the highest concentrations in all metals, mainly Fe (103.751 ± 92.151 mg/kg) and Al (28.908 ± 21.221 mg/kg). Therefore, this study highlights that the selection of the species taking into account feeding and habitat partitioning must be carefully considered being crucial to identify fish groups as biological indicators of marine pollution.

Metal content in Mullus surmuletus in the Canary Islands (North-West African Atlantic)

The contents of 3 heavy metals (Al, Cd, and Pb) and 10 trace elements (B, Cr, Cu, Fe, Li, Mg, Ni, Sr, V, Zn) were determined by means of atomic emission spectrometry with inductively coupled plasma (ICP-OES) in 117 specimens of red mullet, Mullus surmuletus. The specimens were taken in two of the Canary Islands; two locations on the island of Tenerife: Candelaria on the northeast coast and Punta de Hidalgo on the north coast and Arguineguín, on the south coast of the island of Gran Canaria. No significant differences were found between the two sites in Tenerife regarding the metal content of the specimens studied, but differences were found between the specimens captured in Arguineguín and the two sites in Tenerife, the latter having higher concentrations of the analyzed metals.

Mercury and cadmium distribution in yellowfin tuna (Thunnus albacares) from two fishing grounds in the Indian Ocean near Sri Lanka

Mercury (Hg) and cadmium (Cd) are contaminants of great environmental concern due to their natural and anthropogenic origin, their ability of bioaccumulate through the food chain and their harmful effects on human health. In this study, the Hg and Cd accumulation in the muscle of 65 yellowfin tuna (Thunnus albacares) collected from two different catching sites of the Indian Ocean near Sri Lanka were evaluated. The samples were mineralized using microwave accelerated digestion, and the metals were detected by atomic absorption spectroscopy (AAS). The metal levels were not significantly different between the two sites (p > 0.05), and the average Hg and Cd concentrations were 0.48 ± 0.35 mg/kg and 0.017 ± 0.024 mg/kg, (wet weight basis) respectively. Only 6 (9.2%) and 2 samples (3.1%) exceeded the European Commission limits for Hg (1 mg/kg) and Cd (0.01 mg/kg), respectively. A comparatively strong positive correlation was observed between the THg concentration and the weight of the fish. However, there was no clear relationship between the concentration and size for Cd. These findings provide an understanding of the Hg and Cd distribution in yellowfin tuna in two fishing grounds in the Indian Ocean near Sri Lanka.

Accumulation of PCBs, PAHs, plasticizers and inorganic elements in Hexanchus griseus from the strait of Messina (Central Mediterranean sea)

This study investigates the inorganic elements and the persistent organic pollutants (POPs) accumulated in liver of a sexually mature Hexanchus griseus living in the Mediterranean Sea. The casual finding of a specimen in the Strait of Messina (April 2018) allowed us to carefully analyse its liver which can be considered a very important biological indicator. The determination of inorganic elements was carried out by ICP-MS technique. Quantitative determination of polycyclic aromatic hydrocarbons (PAH) and poly-chloro-biphenyl compounds (PCB), distinguished in dioxine-like (DL) and not-dioxine-like (NDL) derivates, has been carried out by HRGC/MS and HRGC-MS/MS respectively. Worrying levels of PCB-DL (TEQ = Σ(PCB-DL)*TEF = 5.96 ng g^-1), PCB-NDL (Σ(PCB-NDL) = 1390.4 ng g^-1) together with the presence of pesticides and plasticizers were found in the shark liver oil. The levels of heavy metals were below the legal limits.

Determination of Hg in Farmed and Wild Atlantic Bluefin Tuna (Thunnus thynnus L.) Muscle

Mercury (Hg) is a well-known toxic element, diffused in the environment, especially in the Mediterranean Sea which is rich in cinnabar deposits. Mercury bioaccumulation in fish is of great concern, especially for top-level aquatic predators (e.g., shark, tuna, swordfish) and above all for species of large human consumption and high nutritional value. This work aimed to determine Hg concentrations in farmed and wild Atlantic Bluefin tuna (Thunnus thynnus) caught in the Mediterranean area in order to evaluate the level of Hg bioaccumulation. selenium (Se) content was also determined, since this element is an antagonist of mercury toxicity. Mercury and Se were analysed by atomic absorption spectrometry after microwave digestion of the samples. Hg content in farmed tuna was below the legal limit (1 mg/kg, wet weight, w.w.) for all specimens (0.6 ± 0.2 mg/kg), whereas the wild ones had a content over the limit (1.7 ± 0.6 mg/kg); Se concentration was higher in farmed specimens (1.1 ± 0.9 mg/kg) compared to wild ones (0.6 ± 0.3 mg/kg). A safe seafood could show a Se/Hg ratio >1 and a health benefit value (HBV_Se) > 0: farmed tuna had higher values than the wild specimens (Se/Hg 5.48 vs. 1.32; HBV_Se 11.16 vs. 0.29). These results demonstrate that for Hg, there is a better risk/benefit ratio in farmed T. thynnus. making it safer than wild tuna.

Seasonal trend of Anisakidae infestation in South Mediterranean bluefish

A total of 1104 fish samples from markets of Sicily were analysed for the detection and species identification of Anisakidae nematodes. The preliminary analysis of the fish samples showed the presence of 2459 larvae. All the fish species revealed different prevalence of infestation, with a maximum of 100% for Lepidopus caudatus and a minimum of 4.5% in Sardina pilchardus. The 80% of the larvae examined by PCR-RFLP analysis belonged to Anisakis pegreffii species. The seasonal infestation trend of Anisakis was evaluated in all the fish sample examined. The results of the seasonal infestation trend showed a marked connection with the ecological aspects of the fish species examined. As far as we know, this work report for the first time important ecological aspects of Lepidopus caudatus specimens of South Mediterranean. This work could be useful to plan a seasonal fishing strategy aimed at reducing the health risks related to Anisakis.

Systematic review of arsenic in fresh seafood from the Mediterranean Sea and European Atlantic coasts: A health risk assessment

Arsenic in the environment pose major threats to human health, and especially the inorganic form can result in adverse health effects. This review analyse papers from 2004 to 2017 on As in fresh fish and molluscs caught in the Mediterranean sea and the European coast of the Atlantic ocean allowing the identification of the marine area with a greater As bioavailability and in particular the identification of the European populations more exposed to In-As by consuming fresh seafood. Results were separated on the base of the fishing site and the concentrations were reworked to assess the average daily intake to In-As as well as Target Hazard Quotient and Cancer Risk. Overall, the greater availability in Tot-As concentration in the pelagic compartment found in the Mediterranean Sea is not present along the European coasts of Atlantic Ocean. Furthermore, only in the Mediterranean Sea, results highlighted significant differences between Tot-As concentrations in seafood subgroups. In both areas, In-As concentrations showed the following trend: molluscs > pelagic > demersal with significant differences between subgroups. The European populations more exposed to In-As from fish and molluscs are the French, Spanish, Italian and Greek, with particular regards to children of 3-6 years old, which should minimize the consumption of molluscs to avoid carcinogenic and non-carcinogenic risks.

Investigation of Hg Content by a Rapid Analytical Technique in Mediterranean Pelagic Fishes

Mercury (Hg) fish and seafood contamination is a global concern and needs worldwide sea investigations in order to protect consumers. The aim of this study was to investigate the Hg concentration by means of a rapid and simple analytical technique with a direct Mercury Analyzer (DMA-80) in pelagic fish species, Tetrapturus belone (spearfish), Thunnus thynnus (tuna) and Xiphias gladius (swordfish) caught in the Mediterranean Sea. Hg contents were evaluated also in Salmo salar (salmon) as pelagic fish not belonging to the Mediterranean area. The results obtained were variable, ranging between 0.015–2.562 mg kg−1 for T. thynnus species, 0.477–3.182 mg kg−1 for X. gladius, 0.434–1.730 mg kg−1 for T. belone and 0.004–0.019 mg kg−1 for S. salar, respectively. The total Hg tolerable weekly intake (TWI) and tolerable weekly intake % (TWI%) values according to the European Food Safety Authority (EFSA) were calculated. The results highlighted that the pelagic species caught in the Mediterranean Sea should be constantly monitored due to their high Hg contents as well as their TWI and TWI% with respect to S. salar samples.

Comparison of elemental composition in two wild and cultured marine fish and potential risks to human health

Among all available species, fish are a powerful model for risk-benefit assessments to study the effects of contaminants on human health. Gilthead seabream (Sparus aurata, Linnaeus 1758) and european seabass (Dicentrarchus labrax, Linnaeus 1758) are two species of great economic importance, representing very large production volumes in the Mediterranean. The objective of this study is (1) to analyze the concentrations of Trace Elements (TE) between wild and cultured seabream and seabass specimens, (2) to compare the determined concentrations with other studies, and (3) to increase the data about the potential risks to human health. Our results point to significant intra- and interspecies-specific differences between wild and cultured fish for several trace elements. Several strong and moderate inter-elemental correlations in fish muscle were observed through correlation analysis. In our study, the mean levels of trace elements were still below the standard safety values for fish intended for human consumption. The same results were reached for all the parameters analyzed (international legal limits, estimated weekly intake, provisional tolerable weekly intake, target hazard quotient, target cancer risk), with trace element levels in fish below those that could pose a risk to human health. Consequently, these fish can be considered safe for human consumption. A better understanding of the levels of trace elements in fish would also better inform consumers about the potential risks of exposure to contaminants.

Arsenic, cadmium and lead in fresh and processed tuna marketed in Galicia (NW Spain): Risk assessment of dietary exposure

Currently, metal bioaccumulation in fish is increasing and is a cause of concern due to toxicity. Total arsenic, cadmium and lead concentrations in fresh and processed tuna (110 samples) marketed in Galicia (NW Spain) were determined by ICP-MS spectrometry. The average concentrations of As and Cd, 3.78 and 0.024 mg kg^-1 w.w., respectively, in fresh tuna were statistically significantly higher than those in processed tuna (p < 0.001). The contents in processed tuna were 0.295-7.85 mg kg^-1 for As and ND-0.045 mg kg^-1 for Cd. The Pb content was negligible in both types of tuna. In canned tuna, decreasing As and Cd concentrations were observed in different preparation-packaging media: olive oil > natural > pickled sauce. Of the two species studied in canned tuna, Thunnus alalunga showed statistically significant higher levels both for As 1.28 mg kg^-1 (p < 0.001) and Pb 0.013 mg kg^-1 (p = 0.0496) than Thunnus albacares. No samples surpassed the limits set by the EU for Cd and Pb. The limit for As in fish has not been established, but the arsenic contents in fresh tuna reported here are important, as they are among the highest reported in the literature. Considering public health in children and adults with respect to the investigated metals, the estimated daily intakes (EDIs) did not exceed the tolerable intakes. No chronic systemic risk was found since all the target hazard quotients (THQs-TTHQs) were far below 1 (critical value), and the carcinogenic risk (CR) for As did not exceed the acceptable value of 10^-5. Thus, tuna consumption in the Galician diet does not pose a risk for different population groups in terms of these studied metals/metalloids.

In vivo effects of PCB-126 and genistein on vitellogenin expression in zebrafish

In this study, the vitellogenin (Vtg) modulation by genistein and polychlorinated biphenyl-126 (PCB-126) exposure in zebrafishes has been investigated. Both PCB-126 and genistein have been identified as aquatic pollutants and can further increase estrogenicity of waterways. Vtg is egg yolk precursor protein release by the hepatocytes during vitellogenesis. This process occurs normally in the hepatocytes in response to the activation with the estrogens such as 17-β-estradiol. Our immunohistochemical findings showed a Vtg expression that increases at 12 h and at 72 h in the liver of treated fishes with both PCB-126 and genistein, individually and in combination. Furthermore, for the first time, also hepatic stellate cells (HSC) in the liver parenchyma were strongly positive for vitellogenin.

Occurrence of aflatoxin M1 in milk samples from Italy analysed by online-SPE UHPLC-MS/MS

The occurrence of aflatoxin M1 in 69 milk samples collected in a south region of Italy in 2016 was evaluated. The samples were analysed using an automated method based on online SPE coupled with UHPLC tandem mass spectrometry. After a salt induced liquid-liquid extraction with acetonitrile to remove protein from milk, the extract was diluted with water and analysed using an automated online SPE MS/MS method. Among the analysed samples no one had AFM1 higher than the legally allowable limits whereas 71.4% of the other analysed samples were above the LOD of the method. The highest contamination level of AFM1 was found in pasteurised milk (44.39 ng kg^-1). The results show the worrying and widespread of AFM1 contamination, highlighting the necessity of monitoring studies in order to evaluate the reduction of the maximum legal limit.

Effects of dietary sesame oil on growth performance, chemical composition, lipid oxidation, and sensory characteristics of rainbow trout Oncorhynchus mykiss

The present study, the effects of dietary sesame oil (SO) on growth performance and fillet composition of rainbow trout (Oncorhynchus mykiss) were investigated. Twenty-five fish were randomly allocated in three groups by three replication, in mean initial weight 53.3 g in each tank. Experimental diets consisted of fish oil (FO), sesame oil (SO) and 1:1 blends of two oils, fish oil and sesame oil (FOSO). Dietary sesame oil had no significant effect on growth rate or feed conversion ratio. Similarly, no significant differences were observed between dietary treatments for ash content in fillet of fish. The fillet lipid content was lower in fish fed by sesame oil, but the moisture and the protein were higher. Furthermore, Thiobarbituric acid (TBA) test was changed in different groups and it was lower in SO. The organoleptic indices were affected by dietary oils and FO group had more fishy flavour.

Trace element concentrations in the apex predator swordfish (Xiphias gladius) from a Mediterranean fishery and risk assessment for consumers

Swordfish (Xiphias gladius L., 1758) is an apex predator, highly migratory meso-pelagic fish widely distributed in the Atlantic Ocean and Mediterranean. As top predators, this fish may be the end reservoir of the bioaccumulation of trace elements in a food chain because they occupy higher trophic levels and are an important food source, causing them to be potentially hazardous to consume. This study aims to investigate the concentration of 18 trace elements of Swordfish, caught in the Mediterranean Sea and to discuss human exposure risks. The mean element levels in the fish muscles were clearly below the maximum allowable concentrations established by International food safety regulations. The data suggested that the risk is minor and acceptable for human health. The findings of this study amplify the scarce database on contaminants available, especially new data on "emerging elements", for this species from the Mediterranean Sea.

Removal of heavy metal ions from wastewaters using dendrimer-functionalized multi-walled carbon nanotubes

Dendrimer-functionalized multi-walled carbon nanotubes (MWCNT) for heavy metal ion removal from wastewaters were developed. Triazole dendrimers (TD) were built directly onto the carbon nanotube surface by successive click chemistry reactions affording the zero- and first-generation dendrimer-functionalized MWCNT (MWCNT-TD1 and MWCNT-TD2). The Moedritzer-Irani reaction carried out on the amino groups present on the MWCNT-TD2 sample gave the corresponding α-aminophosphonate nanosystem MWCNT-TD2P. Both MWCNT-TD2 and MWCNT-TD2P nanosystems have been characterized by physical, chemical, and morphological analyses. Their chelating abilities towards the toxic metal ions Pb²⁺, Hg²⁺, and Ni²⁺ and the harmless Ca²⁺ ion have been experimentally evaluated in the two different sets of experiments and at the salt concentrations of 1 mg/mL or 1 μg/mL by inductively coupled plasma mass spectrometry (ICP-MS). The results of these studies pointed out the interesting chelating behavior for the phosphonated nanosystem towards the Hg²⁺ ion. The complexation mode of the best chelating system MWCNT-TD2P with mercury was investigated through density functional theory (DFT) calculations, suggesting a chelation mechanism involving the two oxygen atoms of the phosphate group. The synthesized dendrimers, supported on the multi-walled carbon nanotubes, have shown the potential to be used for the selective toxic metal ion removal and recovery.