Heavy metals, lipid peroxidation, and ciguatera toxicity in the liver of the Caribbean barracuda (Sphyraena barracuda)

Health risk assessment of heavy metals in the seafood at Kalpakkam coast, Southeast Bay of Bengal

The distribution of heavy metals in the seafood intake by various age group representatives around the Kalpakkam coastal region was part of the baseline study. Totally 40 different types of fish species were estimated on heavy metals (Cu, Cr, Co, Cd, Pb, Ni, Zn, and Mn) in the coastal zone; the average concentration of heavy metals were 0.71, 0.06, 0, 0, 0.07, 0.02, 1.06 and 0.36 ppm, respectively. Individual mean bioaccumulation index (IMBI) and Metal pollution index (MPI) with heavy metals distributed around the coastal zone were compared with fish tissue and were found to be higher for Zn and Cu. The human health risk was calculated using uncertainty modeling of risk assessment of Estimated daily intake (EDI), Maximum allowable consumption rate (CRlim), Target hazard quotient (THQ), and Hazard index (HI) were estimated for different age groups. Our present values were suggestively high (>1) for both kids and adults. The cumulative cancer risk assessment based on heavy metals and the Hospital-Based Cancer Registry (HBCR) compared to the region did not exceed the recommended threshold risk limit around the Kalpakkam coastal zone. Statistical analyses such as correlation, Principal component, and Cluster investigation ensure that heavy metal concentrations do not pose a major risk to occupants.

Metal pollution and potential human health risk assessment in major seafood items (fish, crustaceans, and cephalopods)

Global seafood consumers are increasingly concerned about and prefer safe, high-quality, and hazard-free seafood products. This study investigated various Pakistani processing plants supplying the international market and explored commercially important seafood species (fish, crustaceans, and cephalopods) for metal content, contamination, and potential health risks. The results showed that the metal concentrations differed significantly among species. The metals loads were as Fe > Cu > Zn > Mn > Pb > Ni > Cd > Hg. Contamination factor (CF), pollution load index (PLI), and metal pollution index (MPI), verified negligible contamination of seafood. As assessed by the estimated daily intake, target hazard quotient, hazard index, and carcinogenic risk, the potential human health risks associated with the contaminated seafood were lower than the perceived threat. In conclusion, seafood processing plants export products that meet international food safety standards and are safe for consumers worldwide.

Health risk assessment and metal contamination in fish, water and soil sediments in the East Kolkata Wetlands, India, Ramsar site

East Kolkata Wetlands (EKW) is an important site for fish culture in sewage-fed areas, which are major receivers of pollutants and wastages from Kolkata. EKW is internationally important as the Ramsar site was declared on Aug 2002 with an area of 125 km². EKW is a natural water body where wastewater-fed natural aquaculture has been practiced for more than 70 years. It is ecologically vulnerable due to the discharge of toxic waste through sewage canals from cities. Assessing the EKW to understand the inflow and load of the toxic metal (s) in fish, water, and sediments samples is essential. The field (samples collection from 13 sites) and lab (determination of toxic level of metals) based research were carried out to assess metal toxicity and health risk assessment in EKW. The levels of eighteen metals (18), namely Chromium, Vanadium, Cobalt, Manganese, Copper, Nickel, Zinc, Silver, Molybdenum, Arsenic, Selenium, Tin, Gallium, Germanium, Strontium, Cadmium, Mercury, and Lead, were determined using Inductively coupled plasma mass spectrometry (ICP-MS) in five fish tissues viz. muscle, liver, kidney, gill and brain, along with the water samples and soil sediments in 13 sampling sites. The bioaccumulation and concentration of metals in fish tissues, soil sediments, and water samples were well within the safe level concerning the recommendation of different national and international agencies except for a few metals in a few sampling sites like Cd, As, and Pb. The geoaccumulation index (Igeo) was also determined in the soil sediments, indicating moderate arsenic, selenium, and mercury contamination in a few sites. The contamination index in water was also determined in 13 sampling sites. The estimated daily intake (EDI), reference dose (RfD), target hazard quotient (THQ), slope factor and cancer risk of Cr, Mn, Co, Ni, Cu, Zn, As, Se, Cd, Pb and Hg from fish muscle were determined. Based on the results of the present investigation, it is concluded that fish consumption in the East Kolkata Wetland (EKW) is safe. The effects of bioaccumulation of metals in muscle tissue were well within the safe level for consumption as recommended by WHO/FAO.

Public awareness of seafood mislabeling

A substantial portion of seafood is mislabeled, causing significant impacts to human health, the environment, the economy, and society. Despite the large scientific literature documenting seafood mislabeling the public's awareness of seafood mislabeling is unknown. We conducted an online survey to assess the public's awareness and perceptions of seafood mislabeling. Of the 1,216 respondents, 38% had never heard of seafood mislabeling and 49% were only 'vaguely familiar' with it. After being provided the definition of seafood mislabeling 95% had some degree of concern. Respondents were the most concerned about environmental impacts caused by seafood mislabeling and the least concerned about the social justice implications. Respondents who were also more concerned and familiar with seafood mislabeling stated that they would be more likely to purchase seafood from a vendor where the labeling was independently verified.

Human Activity in Antarctica: Effects on Metallic Trace Elements (MTEs) in Plants and Soils

Colobanthus quitensis (Kunt) is one of the two vascular plant species present in Antarctica and develops under severe environmental conditions, being found in both pristine and human-threatened environments. We determined the Cd, Cr, Cu, Mn, Ni, Pb, and Zn levels in C. quitensis roots, leaves, and soils of origin using flame atomic absorption spectroscopy. In January 2017, we collected samples from four geographical zones on the longitudinal gradient along which C. quitensis is distributed, starting from Punta Arenas (PAR) at the extreme south of mainland Chile and moving southwards to the Antarctic territory from King George Island (KGI) to Hannah Point Peninsula (PHA) and finally Lagotellerie Island (LAT). We used certified reference material to validate the plant tissues and soil samples we collected. The highest concentrations of metals that we measured in the soils and in the C. quitensis roots and leaves were in samples we collected at the KGI station, the zone with the greatest human activity. The lowest concentrations we measured were at the LAT station, an island with little human intervention and scarce fauna. The mean concentrations of metals in the roots and leaves of C. quitensis followed a similar order at all sampling locations: Mn > Zn > Cu > Ni > Pb > Cr > Cd. In contrast, in soil, they followed the following order: Mn > Zn > Cu > Cr > Pb > Ni > Cd. The concentration levels obtained for the different metals in the soil and plants tissue samples in this region of Antarctica indicated that the area was non-polluted. However, the metallic trace element (MTE) concentrations may be at an early stage of contamination, as described in other areas of the Antarctic, being a new threat to this continent.

Metal pollutant pathways in cohesive coastal catchments: Influence of flocculation and biopolymers on partitioning and flux

The impacts of the partitioning of potentially toxic metals (PTM) within the estuarine environment is highly complex, but is of key significance owing to increases in populations living within such sensitive environments. Although empirical data exist for the partitioning of metals between the dissolved and particulate phases, little is known regarding the impacts of extracellular polymeric substances (EPS) upon the flocculation of particles within such a dynamic system nor the resultant influence on the distribution of metals between the particulate and dissolved phases. This prevents regulators from fully understanding the fate and risks associated with metals in estuaries. This study provides data associated with the simulation of 3 settlings typical of the turbulent mixing found in estuaries and partitioning of copper, cadmium, nickel, arsenic, lead and zinc for 3 salinities (0, 15, 30 PSU) reflecting the full salinity range from freshwater to seawater. Experiments were completed with and without the presence of EPS, using kaolin as the mineral particulate. The results showed significant differences between salinity, PTMs and turbulence for the experiments with and without EPS present. Overall, salinity was the main factor controlling the PTM partitioning to sediment, however the flocculation process did impact on the PTM distribution and with the addition of EPS the impact was more pronounced. The data highlighted the importance of taking account of EPS within any estuarine sediment process modelling, for relying on simple partitioning with corrections for salinity would likely lead to significant bias.

Spatial trace element bioaccumulation along with consumer risk simulations of Mediterranean mussels in coastal waters of Turkey

Turkey borders three seas and the most populous locations are squeezed into the coastal territories. Thus, organisms living in these aquatic territories are under longstanding anthropogenic pressure. Hence, this study investigated the consumption outcomes leading to potential child and adult health risks along with the spatial distribution of As, Cd, Cr, Cu, Ni, Pb, V, and Zn in the Mediterranean mussels (Mytilus galloprovincialis) sampled at 23 different stations from the Black Sea, the Sea of Marmara, and the Aegean Sea coastal waters of Turkey. The mean concentrations of trace elements found in the Mediterranean mussels followed Zn (39.75 mg kg^-1) > Cu (1.95 mg kg^-1) > As (1.84 mg kg^-1) > Pb (0.99 mg kg^-1) > Ni (0.65 mg kg^-1) > Cr (0.62 mg kg^-1) > V (0.47 mg kg^-1) > Cd (0.08 mg kg^-1). Factor analysis revealed that trace elements were mostly derived from anthropogenic sources. Pb values were found to be above the permissible European Union limits at 10 sampling stations. While the estimated weekly intake did not exceed the Joint FAO/WHO Expert Committee on Food Additives limits, the target hazard quotient for As was found >1 for children. The lifetime cancer risk (CR) for adults and children was unacceptable (>10^-4) at high consumption rates for As according to US Environmental Protection Agency. Monte Carlo simulation confirmed a CR to adult (62.98%) and children (97.24%) mussel consumers caused by As.

Relationship Between Heavy Metal Accumulation in Fish Muscle and Heavy Metal Resistance Genes in Bacteria Isolated from Fish

Cadmium, cobalt, copper, nickel, and zinc are the most common pollutant heavy metals that can be discharged into the marine environment with different sources. Whiting (Merlangius merlangus) and mullet (Mullus barbatus) were sampled in four seasons in a year to determine Cd, Co, Cu, Ni, and Zn levels in the muscle and to determine heavy metal resistance genes (MRGs) such as copA, czc, and ncc genes in coliform bacteria isolated from the fish. In both species, zinc was the most abundant metal, while Cd and the Co levels were scarce. Co level was significantly higher in summer in mullet than that of whiting (p < 0.001). The most prevalent MRGs was determined as copA (46.2%) followed by czc (35.8%) and ncc (17.9%). Increased Co and Ni level in the muscle significantly affected the presence of ncc gene in bacteria, while the presence of ncc and copA genes was affected by Ni and Cu levels found in the fish muscle. There was a significant positive correlation between Cd level in the muscle and presence of czc and ncc gene in the bacteria (p < 0.029). When the levels of Cu, Zn, and Cd increased in the muscle of the fish, occurrence of MRGs genes was increased significantly (p < 0.0001). A strong positive correlation was found between heavy metal resistance levels in fish and the prevalence of E. coli and coliforms that harbor heavy metal resistance genes which will be a problem in aquaculture, aquatic ecosystem, and public health.

Assessment of potential human health risk due to heavy metal contamination in edible finfish and shellfish collected around Ennore coast, India

This study aims to estimate anthropogenic sources of pollutants such as heavy metals that pollute or poison the commercial marine finfish and shellfish present around the Ennore coastal area and to identify, quantify and manage the associated risks for the betterment of society. The levels of toxic heavy metal concentrations from monitoring and surveillance of copper, chromium, cadmium, mercury, lead and zinc heavy metals were estimated from water, sediment and commercial marine finfish and shellfish samples that were collected for study. The individual mean bioaccumulation index (IMBI) and Metal Pollution Index (MPI) values varied between finfish and shellfish. Target hazard quotient (THQ) index values were calculated, and copper and zinc were found to be elevated at levels affecting children in particular. Thus, efforts are urgently needed to resolve the current and potential risks associated with the negative impact of heavy metal intake from seafood on human health. This study attempts to identify levels of metal contamination and corresponding risk factors with regard to human health.

Is eating wild rainbow trout safe? The effects of different land-uses on heavy metals content in Chile

Cu, Mn, Fe, Zn, Cd and Pb levels were measured in liver and muscle samples of Rainbow Trout Oncorhynchus mykiss collected from three watersheds with different land-uses: native forest, exotic plantation, and agriculture in Chile, during January, April, July, and October 2012. Cd and Pb levels were not detected in the liver and muscle, probably since they are under the detection limits. Higher metal concentrations (liver-muscle tissues) were detected in samples from agriculture and exotic plantation streams, whereas trout from native forest streams had lower metal concentrations. Higher metal concentrations were detected in liver tissue compared to muscle tissue, and both negatively correlated to the length and weight of the fish. This suggest the liver had higher ability to accumulate Cu, Mn, Fe and Zn compared to muscle tissue. The concentration range of Fe and Zn recorded in the muscle are within the range reported by other authors, whereas Mn and Cu concentrations are higher than reported in the literature. However, at all sites the concentration of selected metals were below the limits permitted by current legislation (FAO), and therefore did not put the human population at risk, suggesting that is eating wild rainbow trout safe in Chile.

Concentration of heavy metals in seafood (fishes, shrimp, lobster and crabs) and human health assessment in Saint Martin Island, Bangladesh

A contaminated aquatic environment may end up in the food chain and pose risks to tourist health in a tourist destination. To assess the health risk for tourists that visit St. Martine Island, which is a popular domestic and foreign tourist destination in Bangladesh, a study is undertaken to analyse the level of heavy metal contamination from chromium (Cr), manganese (Mn), copper (Cu), zinc (Zn), arsenic (As), cadmium (Cd), lead (Pb), mercury (Hg) and iron (Fe) in six of the most consumed fish (L. fasciatus, R. kanagurta, H. nigrescens, P. cuneatus, P. annularis and S. rubrum) and five crustacean species, which consist of a shrimp (P. sculptilis), a lobster (P. versicolor) and three crabs (P. sanguinolentus, T. crenata and M. victor) captured. The samples were analysed for trace metals using atomic absorption spectrometer, and the concentrations of the metals were interpreted using the United State Environmental Protection Agency (USEPA) health risk model. The muscle and carapace/exoskeleton of shrimp, lobster and crabs were analysed and contained various concentrations of Pb, Hg, As, Cr, Cd, Fe, Cu, Zn and Mn. The hierarchy of the heavy metal in marine fish is Fe > Cd > Zn > Pb > Cu > Cr > Mn > Hg. The concentrations of Pb in the species R. kanagurta, H. nigresceus and S. rubrum were above the food safety guideline by Australia, New Zealand and other legislations in most marine fish and crustaceans. Crabs showed higher mean heavy metal concentrations than shrimp and lobster. Acceptable carcinogen ranges were observed in three fish species (R. kanagurata, H. nigresceus and S. rubrum) and one crustacean species (P. sculptilis) samples.

Heavy metal concentrations in wild fishes captured from the South China Sea and associated health risks

Heavy metal concentrations were measured in 29 marine wild fish species from the South China Sea. Concentrations (wet weight) were 0.51-115.81 ng/g (Cd), 0.54-27.31 ng/g (Pb), 0.02-1.26 μg/g (Cr), 8.32-57.48 ng/g (Ni), 0.12-1.13 μg/g (Cu), 2.34-6.88 μg/g (Zn), 2.51-22.99 μg/g (Fe), and 0.04-0.81 μg/g (Mn), respectively. Iron concentrations in all and Mn in some fish species were higher than the acceptable daily upper limit, suggesting human consumption of these wild fish species may pose a health risk. Human health risk assessment, however, indicated no significant adverse health effects with consumption.

Comparison of metal levels in different tissues of seven ray species from Antalya Bay, Mediterranean Sea

The aim of this study was to investigate the metal concentrations in muscle, liver, gill and intestine of seven ray species from Antalya Bay. Because the study is the first for rays in Antalya Bay, this study provides valuable preliminary information about metal contents in different tissues of the examined ray species from the bay and indirectly indicates the environmental contamination of the Antalya Bay.

Study of seasonal variations and health risk assessment of heavy metals in Cyprinus carpio from Rawal Lake, Pakistan

This study was carried out to find out the comparative distribution of heavy metals (Fe, Cu, Mn, Zn, Co, Cr, Cd and Pb) in various tissues (muscles, gills, liver, stomach and intestine) of Cyprinus carpio from Rawal Lake, Pakistan, during summer and winter. Relatively higher concentrations of Cd, Co, Cr, Cu, Fe and Zn were found in the stomach samples, while the highest Pb and Zn levels were noted in muscle and intestine samples, respectively. Correlation study exhibited diverse relationships among the metals in various tissues. Generally, the metal concentrations found during the summer were comparatively higher than the winter. Potential non-carcinogenic and carcinogenic health risks related to the metals in C. carpio were evaluated using the US Environmental Protection Agency approved cancer risk assessment guidelines. The calculated daily and weekly intakes of Pb, Cd, Cr and Co through the fish consumption were significantly higher than the permissible limits. In relation to the non-carcinogenic risks to human, Pb, Cd, Cr, Co and Zn levels were higher than the safe limits; however, carcinogenic risks related to Cr (3.9 × 10(-3) during summer and 1.1 × 10(-3) during winter) and Pb (2.6 × 10(-4) during summer and 1.5 × 10(-4) during winter) clearly exceeded the safe limit (1 × 10(-6)). Consequently, the consumption of C. carpio from Rawal Lake on regular basis was considered unsafe.

Essential, trace and toxic element concentrations in the liver of the world's largest bony fish, the ocean sunfish (Mola mola)

No studies document essential (calcium, magnesium, phosphorus, potassium, sodium), trace (barium, boron, chromium, cobalt, copper, iron, manganese, molybdenum, selenium, zinc) or toxic element (antimony, arsenic, cadmium, lead, mercury, thallium) concentrations in any members of the family Molidae, including the world's largest bony fish, the ocean sunfish (Mola mola). Here, we analyzed 21 elements in the liver of one M. mola. These values were compared to liver concentrations in multiple species with spatial and dietary overlap. Concentrations of calcium (3339 ppm wet weight) and iron (2311 ppm wet weight) were extremely elevated in comparison to a number of other fish species, indicating that calcium and/or iron toxicity may have occurred in this animal. Concentrations of toxic elements were generally low, with the exception of cadmium (3.5 ppm). This study represents the first report of essential, trace and toxic elements in this species.

Harmful metals concentration in sediments and fishes of biologically important estuary, Bay of Bengal

Study on the accumulation level of heavy metals was conducted on sediment and fishes from estuaries of Bay of Bengal. Heavy metals were determined by using Inductively Coupled Plasma Optical Emission Spectrometer (ICP-OES) and the results were compared to permissible limits of WHO/USEPA. The accumulation patterns of Fe and Cd were found predominantly in all samples tested when correlated with other metals. It was found that the concentration of metals such as Cd (3.90 ± 0.25 μg/g), Cr (0.44 ± 0.05 μg/g), Ni (0.33 ± 0.01 μg/g), and Mn (1.1 ± 0.11 μg/g) were exceeding the permissible limit, whereas Fe, Co, Pb, and Zn were found within the limit of WHO/USEPA at station 1. In station 2, Cd (16.5 ± 0.4 μg/g), Mn (0.67 ± 0.11 μg/g), and Cr (0.80 ± 0.01 μg/g) were exceeding the permissible limit, whereas Fe, Co, Pb, Ni, and Zn were found within the limit. This study emphasizes that Cd and Mn levels in both stations, are far higher than the acceptable values set by WHO/USEPA and may therefore present human health hazards. It is therefore mandatory to carry out extensive research to evaluate the possible environmental risk factors in the vicinity of both estuaries with respect to heavy metals.

Distribution patterns of toxic metals in the marine oyster Saccostrea cucullata from the Arabian Sea in Oman: spatial, temporal, and size variations

The variations in size and spatial and temporal variations in concentrations of toxic metals (cadmium, mercury, and lead) in oyster tissues were studied. Samples were collected at monthly intervals over a 1-year period from three locations along the southern coast of Oman (Mirbat, Hadbeen, and Sadah). Cadmium and lead were analyzed using an inductively coupled plasma atomic emission spectrometer, and mercury was analyzed using a direct mercury analyzer. The annual mean concentrations in oyster tissues sampled from the three locations and from different time periods ranged from 2.64 to 3.80 mg kg(-1) for cadmium, 0.009 to 0.02 mg kg(-1) for lead, and 0.01 to 0.02 mg kg(-1) for mercury. The temporal effect on cadmium concentrations was more distinct than the local site-specific effect, with higher concentrations recorded in tissues during the summer season than in the winter season. Moreover, within each site, a significant time-specific dependence on the toxic metal concentration differences was recorded. Lipid content was found to influence mercury concentrations in the oysters; however, there was no relationship between cadmium or lead and moisture or lipid content. No distinct relationships were observed between the size of oysters and metal uptake by the oyster. The results were discussed in relation to those obtained from related species in the seas of Oman and worldwide.

Assessment of metal concentrations in commercially important fish species in Black Sea

In the present study, concentrations of arsenic (As), cadmium (Cd), cobalt (Co), chromium (Cr), copper (Cu), manganese (Mn), nickel (Ni), lead (Pb), and zinc (Zn) were measured in the muscle, gill, and gonads of the pelagic fish species Trachurus mediterraneus, Engraulis encrasicolus ponticus, and Sprattus sprattus that are important both commercially and for the ecosystems in the Black Sea. The samples were collected during 2011. The metals were determined using inductively coupled plasma mass spectrometry (ICP-MS) following an acid digestion. The highest concentrations of As, Cd, Co, Cr, Cu, Pb, and Zn were found in E. encrasicolus ponticus, whereas the greatest concentrations of Ni were found in T. mediterraneus and Mn in S. sprattus. Results showed that average metal concentrations in the tissues of T. mediterraneus, E. encrasicolus ponticus, and S. sprattus decreased in the order gill > gonad > muscle, gonad > gill > muscle, and gill > gonad > muscle, respectively, for the three species. When metal concentrations of fish tissues were compared between fish gender, there were only statistical differences in the gonads of the studied fish species (p < 0.05). The present study demonstrated that the metals have different correlations with condition factor (CF) and gonadosomatic index (GSI) of the fish species. Cr showed statistically important positive correlation to the GSI in male T. mediterraneus. Co showed statistically important positive correlation to CF in female E. encrasicolus ponticus, and also Co and Cd showed correlation to CF in male T. mediterraneus. Cd concentrations in the muscle tissues of the fish species were above the maximum acceptable concentration for human consumption.

Heavy metal contamination in the marine organisms in Yantai coast, northern Yellow Sea of China

The port city of Yantai, in Shandong province China is located on Sishili Bay in the northern Yellow Sea. Intense human activity associated with urban sewage discharge, as well as industrial and maritime activities, have stressed the Sishili Bay coastal ecosystem with anthropogenic pollution. The aim of this study was to measure the levels of heavy metal in the sediment and marine organisms of economic value from various sites within Sishili Bay, and to evaluate the data in relation to the potential health risk on human consumers. For this purpose, sediment and wild shrimps and crab were collected from three areas (a total of 13 sampling sites) of the Yantai coast and analyzed for six heavy metals (Cu, Zn, Cr, Ni, Pb, and As). For comparison, the concentrations of the same heavy metals in seven kinds of mollusks obtained from local aquaculture were also determined. The findings showed that the concentrations of heavy metals in the sediment of Yantai coast followed the order Zn > ≈Cr > Cu ≈ Ni ≈ Pb > As, and all were within the safe levels of national standard. However, the concentrations of the heavy metals varied significantly in the organism samples, indicating the different accumulative abilities of the species sampled. For the wild marine organisms, Pb concentrations in some shrimp and crab samples exceeded the standard limit of seafood safety criteria and As concentrations in all samples were over the limit. Moreover, the As levels in mollusks from aquaculture exceeded the limit of seafood standard criteria. These results indicated that the heavy metal levels in the marine organisms in the studied areas were moderate but unacceptable for As from the view of safety of seafood. Furthermore, it is very necessary and important to further study toxicological and ecological effect of As in the coast of northern Yellow sea to understand the potential for risk to human and environmental health.

Comparison of metal accumulation in fish species from the southeastern Black sea

In this study, it was aimed to determine accumulation of the metal concentrations in fish species in different regions which are Sürmene and Yomra bay at southeastern Black sea in Trabzon-Turkey. For this purpose, concentrations of metals (Cr, Co, Ni, Cu, Zn, As, Se, Cd, Sb, Hg, Pb) were measured by inductively coupled plasma mass spectrometry (ICP-MS) in muscle of red mullet (Mullus barbatus ponticus) and whiting (Merlangius merlangus euxinus). Metal concentrations were found for whiting ranged as follows; 0.35-1.64 (Cr), 0.01-0.09 (Co), 0.01-0.71 (Ni), 0.71-1.45 (Cu), 18.64-68.06 (Zn), 2.05-9.66 (As), 0.15-14.16 (Se), 0.01-0.22 (Cd), 0.01-0.01 (Sb), 0.01-0.15 (Hg), 0.01-0.25 (Pb) and for red mullet as 0.43-1.04 (Cr), 0.05-0.23 (Co), 0.02-0.67 (Ni), 0.74-2.32 (Cu), 19.89-43.50 (Zn), 6.04-24.82 (As), 0.02-9.83 (Se), 0.01-0.11 (Cd), 0.01-0.01 (Sb), 0.07-0.18 (Hg), 0.01-0.20 (Pb) μg g(-1) dry weight. Metal concentrations in samples were found to be lower than legal limits proposed by Turkish Food Codex (2008), Food and Agricultural Organization (1983), and European Commission (Off J Eur Union L364-5-L364-24, 2006) for human consumption.

Heavy metals in the liver and muscle of Micropogonias manni fish from Budi Lake, Araucania Region, Chile: potential risk for humans

The concentrations of cadmium, lead, manganese and zinc were determined in the fish species Micropogonias manni captured in Budi Lake, Araucanía Region (Chile). The measurements were made by atomic absorption spectroscopy, and the analysis considered the sex, weight and size of the species; the representative samples were taken from the liver and muscle tissue. The method was validated using certified reference material (DOLT-1). The ranges of concentrations found in the muscle tissue were: Cd, not determinate (n.d.)-0.26; Pb, n.d.-1.88; Mn, 0.02-12.17 and Zn, 0.48-39.04 mg kg(-1) (dry weight). The concentrations in muscle tissue were generally lower than those found in the liver. With respect to the average concentrations recorded for each metal in the edible part of the fish (muscle tissue), it was found that the levels of Cd, Pb, Mn and Zn are within the ranges published by other authors in similar works and below the maximum concentration limits permitted by current legislation (FAO/WHO 2004; EU 2001) and do not constitute a health hazard for consumers of this species. The results were subjected to statistical analysis to evaluate the correlations between the content of the various metals and the sex, weight and size of each sample.

Oxidative stress biomarkers in Senegal sole, Solea senegalensis, to assess the impact of heavy metal pollution in a Huelva estuary (SW Spain): seasonal and spatial variation

The response of wild fish to heavy metals was studied in sole (Solea senegalensis) collected in 2004, 2005 and 2006 at three sampling sites from Huelva estuary (SW Spain), in the vicinity of a petrochemical and mining industry. Heavy metals As, Cd, Cu, Fe, Pb and Zn were analyzed in samples collected from sediment, water and tissue (liver) to examine their bioconcentration and effects in fish such as lipid peroxidation (LPO), catalase (CAT; EC 1.11.1.6), glutathione peroxidase (GPx; EC 1.8.1.7), glutathione S-transferase (GST; EC 2.5.1.18) and glutathione reductase (GR; EC 1.11.1.6) were also analyzed in the fish liver. The results showed different effects in sole from diverse locations with varying degrees of pollution. Significant differences in LPO, CAT and GR activities between control fish and fish from sampling sites were observed as well as seasonal differences for biomarkers. Significant correlations were established between some biomarkers and heavy metals concentrations in liver, sediment and water. This study indicates the usefulness of integrating a set of biomarkers to assess the effects of pollutants in aquatic environments under complex mix of pollutants and chronic pollution situation.

Toxic metals in commercial marine fish in Oman with reference to national and international standards

Commercially important fresh (581) and frozen (292) marine fish samples of 10 species were collected from seafood factories and evaluated using AAS and ICP-OES. Metal levels significantly (p<0.05) varied within and between species. However, there were no significant correlations among metals. There were significant interspecific differences for all metals, and yellowfin tuna had the highest level of cadmium and mercury however, red seabream had maximum numbers above the standards. The metal accumulation significantly varied between bottom feeders of intermediately size locally caught fish. The mean cadmium level ranged from 0.0049 to 0.036 mg kg(-1) and 1.37% of the total samples exceeded the EU and FAO standards. Mean lead content varied between 0.029 and 0.196 mg kg(-1), few samples crossed the EU (2.63%) and FAO (1.6%) limits. Mean mercury level ranged from 0.015 to 0.101 mg kg(-1) and none of the samples exceeded the EU limit. Of the total samples analyzed red seabream (2.06%), yellowfin tuna (1.14%), emperor (0.34%), santer bream (0.22%), king fish (0.11%) and skipjack tuna (0.11%) samples crossed the EU limits. In general, fish from these regions are within the safety levels recommended by various organizations and do not pose a health risk in terms of human diet.

Assessment of metal element concentrations in mussel (M. Galloprovincialis) in Eastern Black Sea, Turkey

The main goal of this work is to determine the effects of pollution of copper, lead and zinc mines on the Eastern Black Sea. Metal and heavy metal concentrations in the Eastern Black Sea mussels were measured using Energy Dispersive X-ray Fluorescence (EDXRF) and Flame Atomic Absorption Spectroscopy (FAAS). The analytical results showed that the tissue of mussel in Eastern Black Sea contains K, Ca, Fe, Cu, Zn, and Sr elements, and the shell of mussel contains Ca, Cu, Sr, and Ba elements. Due to the detection limit of EDXRF, the mussels were analyzed with FAAS for Cr, Mn, Ni, Cd and Pb elements. An ANOVA and Pearson correlation analyses were performed. The results showed although that the mean concentrations of Cu and Zn for the tissue of the mussels were markedly above the permissible levels of the Turkish regulations, Zn concentration is in the limits of the Food and Agriculture Organization (FAO).

Characterization of the developmental toxicity of Caribbean ciguatoxins in finfish embryos

Since oviparous fishes mobilize fat stores to produce eggs, we investigated the potential for deposition of gonadal ciguatoxins to the oil laden yolk sacs which nourish developing embryos, and characterized the effects of these toxins on finfish development. Results showed that ciguatoxins are more concentrated in the egg mass (0.18 ng/g) of a toxic fish than in the muscle (<0.04 ng/g). We used a microinjection technique in a Japanese medaka (Oryzias latipes) developmental fish model to mimic the maternal route of toxin exposure to finfish embryos. We describe the developmental effects of two preparations isolated from Caribbean great barracuda (Sphyraena barracuda): a highly purified toxin (C-CTX-1), and ciguatoxins extracted from the flesh of a toxic fish. C-CTX-1 induced a significant decrease in heart rate after four days, which did not persist with further development. Crude extracts from ciguatoxic fish flesh induced hyperkinetic twitching and severe spinal deformities. These effects were observed in embryos receiving as little as 5 pg/egg, and were consistently found in embryos receiving doses exceeding 10 pg/egg. The occurrence of twitching and spinal deformities increased in both frequency and severity with dose. Larvae suffering from spinal abnormalities were unable to orient themselves, and could not feed, resulting in mortality. The greater distribution of toxin to eggs as compared to flesh suggests that fish with low to moderate (0.5 ppb) flesh toxin levels would maternally transfer detrimental amounts of ciguatoxins to their offspring.

Preliminary report on the levels of elements in four fish species from the Arabian Gulf of Saudi Arabia

This manuscript presents preliminary information on the concentrations of heavy metals: cadmium, lead, nickel, vanadium and arsenic in 66 fish samples of four different species collected from three different sites on the Gulf coast of Saudi Arabia where there are agricultural, municipality and petroleum industrial activities. Fish species; highly consumed by the local population were selected: Emperors, Rabbitfish, Doublebar-bream and Greasy-grouper to ascertain the fish quality for human consumption. The concentration of metals was determined by atomic absorption spectrophotometry (AA). The average mean concentrations (ng/g wet wt.) of cadmium, lead, nickel, vanadium and arsenic in fish tissues were as follows: 4.6 +/- 7.2, 20.0 +/- 20.8, 60.6 +/- 63.2, 73.6 +/- 27.1 and 42.7 +/- 17.4 ng/g wet wt. respectively. The concentration of metals was significantly affected by the sampling site and fish species. In Maniefa site, the concentrations of all tested metals were higher than in Al-Dammam and Dareen sites with the exception of nickel where no significant differences were found. Levels of cadmium, lead, nickel, vanadium and arsenic varied depending on the fish species. The concentration of metals was below the maximum allowed limit by the Saudi and international legislations for fish human consumption permissible limit.

Ciguatera fish poisoning in the Caribbean islands and Western Atlantic

Ciguatera fish poisoning (ciguatera), a common poisoning caused by fish ingestion, is reviewed in the Western Atlantic and the Caribbean waters. It is endemic from Florida coasts (northern limit) to Martinique Island (southern limit), with outbreaks occurring from time to time. In the Caribbean, ciguatera causes a polymorphic syndrome with gastrointestinal, cardiovascular, and neurological signs and symptoms. Neurological and muscular dysfunctions can be treated by intravenous injection of D-mannitol. The lipid-soluble toxins involved are ciguatoxins that are likely produced by the dinoflagellate Gambierdiscus toxicus. G. toxicus strains are endemic in the Caribbean Sea and in theWestern Atlantic. Although it is likely that blooms of G. toxicus are ingested by herbivorous fishes, they are not implicated in ciguatera in the Caribbean. Rather, large carnivores (barracudas, jacks, snappers, groupers), consumers of smaller benthic fish, are often involved in ciguatera. Fish toxicity depends on fishing area and depth, fish size and tissues, and climatic disturbances. Ciguatoxins have been isolated and purified from Caribbean fish species. The structure of two epimers, C-CTX-1 and C-CTX-2 from horse-eye jack, comprise 14 trans-fused ether-linked rings and a hemiketal in terminal ring. Caribbean ciguatoxins are mainly detected in the laboratory by chicken, mouse, mosquito, or cell bioassays, and by analytical HPLC/tandem mass spectrometry down to parts per billion (ppb). A ciguatera management plan that integrates epidemiology, treatment, and a simple method of detection is required to ensure the protection of consumers.