Metals in Fish along the Southeast Coast of India

Metal concentrations (cadmium, chromium, iron, lead, copper, manganese, zinc and mercury) in the muscle of five fish species (Epinephelus chlorostigma, Lutjanus russelli, Terapon jarbua, Cynoglossus arel and Lagocephalus lunaris) from the six fish landing centres along southeast coast of India were measured. In Cuddalore and Mudasalodai, the level of toxic metals cadmium, chromium and manganese were well above the permissible limits. Concentrations of cadmium, chromium, manganese and mercury in C. arel were above the permissible limit and it is consistent with their habitat and diet. The results showed a relationship between metal concentrations and pollution status of the areas.     

Lead Bioaccumulation and Toxicity in Tissues of Economically Fish Species from River and Marine Water

Bioaccumulation of lead was determined in muscle and liver of Barbus xanthopterus, Liza abu, Barbus grypus, Acanthopagrus latus, Platycephalus indicus, Otolithes ruber exposed to lead contaminated river and marine in Khouzestan. Significant variations in metal values were evaluated using student’s t test at p < 0.05. In river fish, liver was polluted in comparison with muscle and high level was in B. xanthopterus (2.80 mg kg⁻¹ wet weight) except for B. grypus in Karkhe River (1.73 mg kg⁻¹wet weight). In marine fish, muscle was contaminated than liver and high level was in O. ruber (47.18 mg kg⁻¹wet weight) except for O. ruber in Mahshahr seaport (17.85 mg kg⁻¹ wet weight).     

Distribution of Metals in the Tissues of Benthic, <Emphasis Type="Italic">Euryglossa orientalis</Emphasis> and <Emphasis Type="Italic">Cynoglossus arel.</Emphasis>, and Bentho-Pelagic, <Emphasis Type="Italic">Johnius belangerii.</Emphasis>, Fish from Three Estuaries,Persian Gulf

Concentrations of Cd, Co, Cu, Ni, Pb, Fe and Zn were determined in the muscle, liver and gills of three commercial benthic and pelagic fish species (Johnius belangerii, Euryglossa orientalis and Cynoglossus arel) from three estuaries in the northwest Persian Gulf. Metals levels varied significantly depending on the tissues, species and locations. Generally, the results showed that liver accumulate higher concentrations of the metals in comparison to muscle and gills, except in few cases. Among the species, E. orientalis showed the highest levels of Co, Cu, Ni and Fe, while the highest concentrations of Pb and Zn were observed in C. arel. J. belangerii accumulated the highest level of Pb element.     

Mercury Speciation in Fish Tissues from a Mediterranean River Basin: The Tagus River (Central Spain) as a Case Study

An assessment of mercury (Hg) accumulation in fish from the Tagus River aquatic system (central Spain), which has been influenced by pollution from industrial and urban development, was performed. Total Hg (THg), inorganic Hg (IHg), and monomethylmercury (MMHg) were determined in muscle and liver of different fish species, including Cyprinus carpio, Ameiurus melas, and Chondrostoma miegii, sampled from three locations. Although concentrations of THg and Hg species showed wide variability among the fish species, they were also found to be considerably dependent on location and fish tissue. Relative contents of MMHg to THg in muscle varied from 60 to 88%, whereas those found in liver ranged from 7 to 59%. Mean THg concentrations ranged from 126 to 810 ng/g (dry weight [dw]) in liver and from 159 to 1057 ng/g dw in muscle. Therefore, the mean THg concentration in all fish muscle samples was far lower than the maximum residue level recommended by the European Union for fishery products. Nevertheless, the concentrations of Hg in fish muscle reported in this study were somewhat increased compared with other areas geographically distant from most major anthropogenic Hg sources and, in some cases, even greater than those previously reported elsewhere in more polluted areas. In contrast, Hg contents in liver were lower than those found in Hg-contaminated areas, but they were within the range found in other areas exposed to diffuse sources of pollution by Hg. Thus, this article provides an overview of the concentration and distribution of Hg species in fish muscle and liver tissues samples taken from a freshwater system in the Mediterranean River basin.     

Mercury Concentrations in Muscle and Liver Tissue of Fish from Marshes Along the Magdalena River,Colombia

The present research determined the total mercury concentrations in muscle and liver tissue in fish collected from the Magdalena River watershed. A total of 378 muscle samples and 102 liver samples were included in the analysis. The highest mean mercury level in muscle tissue was found in the noncarnivore, Pimelodus blochii. However, as a group, carnivores had significantly higher (p < 0.05) mercury levels in their muscle tissue than noncarnivores. A significant correlation (p < 0.05) was obtained between fish mass and mercury concentrations in muscle or liver in four species. No differences were observed in total mercury concentration based either on species or gender.     

Mercury Distribution in Organs of Two Species of Fish from Amazon Region

Total mercury concentrations were determined in muscle, liver and kidney of Cichlia ocellaris and Colossoma macropomum sampled at Tapajos and Carnapijo Rivers in Amazon ecosystem during the flood period of 2009. In background area the highest levels of mercury were observed in liver of piscivorous (0.3 ± 0.03 ug/g dry wt) and non piscivorous fish (0.20 ± 0.1 ug/g dry wt), but in contaminated area the highest level of mercury in piscivorous fish was detected in liver (0.45 ± 0.27 ug/g dry wt) and in muscle (0.26 ± 0.05 ug/g dry wt) of non piscivorous fish. These results suggested that the presence of anthropogenic source plays a key role in the pattern of mercury distribution in fish tissues.     

Determination of Lead, Mercury and Cadmium in Wild and Farmed Barbus sharpeyi from Shadegan Wetland and Azadegan Aquaculture Site, South of Iran

Lead, mercury and cadmium concentrations were measured in muscle, liver and gill in wild and farmed Barbus sharpeyi from Shadegan Wetland (SW) and Azadegan Aquaculture Site (AAS). Significant variation in metal values were evaluated in Students’ tests at p > 0.05. Results showed: In B. sharpeyi high levels of cadmium, lead, and mercury were measured in gill (0.34, 0.68, and 0.06 mg kg⁻¹ dw). The concentration of metals was not significantly different (p ≥ 0.05) in the muscle between SW (Cd, 0.24; Pb, 0.49 and Hg, 0.04) and AAS (Cd, 0.23; Pb, 0.49 and Hg, 0.04). Lead concentration was higher than cadmium and mercury in different organs (p > 0.05). Cadmium, mercury and lead in different tissues of SW were higher than AAS and there was no significant difference between them (p ≥ 0.05). Metal levels in different tissues were higher than WHO standard.     

Polybrominated Diphenyl Ethers in Three Commercially Important Fish from the Northwestern Arabian Gulf: Occurrence,Concentration, and Profiles

Polybrominated diphenyl ethers (PBDEs) were measured in three species of fish (yellowfin seabream [Acanthopagrus latus, a predatory fish]; Klunzinger’s mullet [Liza klunzingeri, a pelagic fish]; and large-scaled tonguesole [Cynoglossus arel, a demersal fish]) collected from two sites in the northwestern part of the Arabian Gulf, a marginal sea of the tropical Indo-Pacific Ocean. Concentrations of ΣPBDEs ranged from 11 to 57 ng g⁻¹ lipid weight (lw) for mullet, 5.0–38 ng g⁻¹ lw for tonguesole, and 2.8–48 ng g⁻¹ lw for seabream in Kuwait Bay, whereas in the open gulf, concentrations ranged from 6.0 to 160 lw for mullet, 8.3–190 lw for tonguesole, and 7.1–62 for lw for seabream. The congener composition in all species from both sites was dominated by BDEs 47, 99, and 100, which together constituted approximately 90% of the congeners detected. Although no statistically significant intersite differences were found, ΣPBDEs concentrations in mullet were significantly higher than those in seabream (p = 0.01). However, no significant differences existed between mullet and tonguesole (p = 0.28) or between tonguesole and seabream (p = 0.06). ΣPBDE concentrations were negatively correlated with fish mass for all species; however, the correlations were statistically insignificant, suggesting a growth dilution effect.     

Contamination of Metals in Tissues of <Emphasis Type="Italic">Ctenopharyngodon idella</Emphasis> and <Emphasis Type="Italic">Perca fluviatilis</Emphasis>, from Anzali Wetland,Iran

The objective of the present study was to investigate the levels of metals (Cd, Cu, Zn, Pb and Cr) in muscle, gill, liver, kidney and intestine of two freshwater fish, Ctenopharyngodon idella and Perca fluviatilis, in Anzali Wetland, Iran. The concentrations were different between the fish species as well as among the tissues of fish. Results showed that the metal concentrations in both fish species were in descending order of Zn > Cu > Pb > Cr > Cd. Results also showed that the Cd, Cu, Zn, and Pb concentrations in the muscle of both fish from Anzali Wetland are below levels of concern for human consumption.     

Assessment of Total Mercury Level in Fish Collected from East Calcutta Wetlands and Titagarh Sewage Fed Aquaculture in West Bengal, India

Total mercury levels were quantified in Tilapia mossambicus, Cirrhinus mrigela and Labio rohita, captured from East Calcutta Wetlands and Titagarh sewage fed aquaculture ponds. The bioconcentration factor of collected fish was assessed. Total mercury level ranged from 0.073 to 0.94 μg/g in both pre and post monsoon season. T. mossambicus in both season and C. mrigela at pre monsoon, cross the Indian recommended maximum limit (0.50 μg/g wet weight) for food consumption and according to World Health Organization guidelines all fish were not recommended for pregnant women and individuals under 15 years ages. A significant correlation was observed between mercury content of aquaculture pond water and fish muscle tissue. Total mercury concentration in experimental sites were higher than the control area (Wilcoxon Ranked-Sum test p > 0.05), which suggested the connection between mercury bioaccumulation and sewage fed aquaculture.     

Total and organic mercury in liver, kidney and muscle of waterbirds from wetlands of the Caspian Sea, Iran

We measured and compared total and organic mercury in liver, kidney, and muscle of the Great Cormorant (Phalacrocorax carbo), mallard (Anas platyrhynchos), and coot (Fulica atra) from the Caspian Sea wetlands in Iran. For the Great Cormorant organic mercury in liver, kidney and muscle comprised 82 %, 79 % and 58 % of total mercury. In the mallard same values were 46 %, 54 %, and 64 %. For coot total mercury was: 0.1 ± 0.0, 0.1 ± 0.01, 0.03 ± 0.01 in liver kidney and muscle respectively. We detected no organic mercury. In general older birds that feed on higher trophic levels can accumulate more mercury in their tissues.     

Metal Concentrations in Tissues of Two Fish Species From Qeshm Island, Iran

The purpose of this study was to determine the concentrations of metals, cadmium, chromium, lead and nickel in Liza vaigiensis and Johnius carutta, in order to: compare metal concentrations between two species with different gender, and to determine the significance between metal concentrations in the gill, liver and muscle. The highest mean concentrations of cadmium, chromium, lead and nickel in different tissues of these two fish species were found in the liver of L. vaigiensis at 0.68, 0.83, 0.37 and 1.42 μg g⁻¹, respectively; while the lowest mean concentrations of cadmium, chromium, lead and nickel were observed in the muscle of J. carutta at 0.16, 0.16, 0.03 and 0.29 μg g⁻¹, respectively. The results showed that the metal concentrations in both species were higher in the females than in the males (except chromium in gill and cadmium in muscle of J. carutta). Also, the results indicated that the metal concentrations were different among fish tissues (one-way ANOVA, p < 0.001), but there was no difference (except lead in gills of J. carutta) between sex (male vs. female).     

Risk to consumers from mercury in Pacific cod (Gadus macrocephalus) from the Aleutians: fish age and size effects

While there has been considerable attention devoted to the risks to high level consumers from mercury in freshwater fish, relatively little attention has been devoted to saltwater fish. Although the U.S. Food and Drug Administration has issued advisories based on mercury for four saltwater species or groups of fish, there are few data on mercury levels generally, or on the risk these levels pose to the fish themselves or to consumers of marine fish. We examined total mercury levels in liver and muscle of Pacific cod (Gadus macrocephalus) collected from the northern Pacific and Bering Sea waters around Nikolski, Amchitka, and Kiska Islands in the Aleutian Chain (Alaska). We were interested in whether there were differences in mercury levels as a function of location, weight, length, and age of the fish, and what risk mercury posed to the food chain, including people. Fish were aged by examining otoliths, and we measured selenium because of its reported protective effects against mercury. Regression models indicated that 27% of the variation in levels of mercury was due to tissue examined and age, while 67% of the variation in levels of selenium was due to tissue, length, and age. Mercury levels were significantly higher in the muscle than the liver, and the reverse was true for selenium. Mercury levels were negatively correlated with selenium levels, and positively correlated with length, weight, and age. There were no gender differences in mercury or selenium levels. The mean levels of mercury in muscle (0.17 ppm wet weight) are within the range known to cause adverse effects in sensitive birds and mammals. Only 4% of the Pacific cod samples had mercury levels above 0.5 ppm, the action level promulgated by many states and countries, and none were above the 1 ppm action level of the U.S. FDA.     

Comparison of Arsenic and Antimony Contents in Tissues and Organs of Brown Trout Caught from the River Presa Polluted by Ancient Mining Practices and from the River Bravona in Corsica (France): A Survey Study

The present study evaluates the concentrations of arsenic (As) and antimony (Sb) in the intestine, liver, muscle, gonads, gills, and kidney of Salmo trutta subsp. from the Presa River in Corsica (France; n = 10), which crosses an abandoned arsenic mine, and from the Bravona River (reference site; n = 10). Both metalloids were analyzed by means of ICP-MS. The relationships between fish size (length and weight) and metalloid concentrations in their tissues were investigated by linear regression analysis. In all fish samples concentrations of As and Sb (expressed as micrograms per gram fresh weight) were highest in the kidney. Lowest Sb concentrations were found in the muscle, whereas lowest As concentrations were found in the gonads of S. trutta. Two organotropisms were revealed: one for As—kidney (21.4656) > intestine (3.9535) > gills (3.0404) > liver (1.1743) > muscle (0.9976) > gonads (0.8081); and the other for Sb—kidney (0.70067) > gills (0.6181) > intestine (0.2576) > gonads (0.1673) > liver (0.9625) > muscle (0.0753). Results of linear regression analysis in most cases showed a significant negative correlation between metalloid concentration and fish size. Highly significant (p < 0.05) negative correlations were found between fish length and As concentration in the gonads, as well as between fish length and Sb concentrations in the gills. Arsenic concentrations in female fish were significantly higher than those in males in the kidney, gonads, gills, and liver. The same results were found for Sb, except in the liver, where the tendency was reversed.     

Mercury concentrations in three species of fish from North Atlantic offshore waters

Mercury concentrations were determined in tissues and organs of spiny dogfish (Squalus acanthias), cusk (Brosme brosme), and blackbellied redfish (Helicolenus dactylopterus) collected from Atlantic Ocean waters off the northeastern coast of the United States. Information was obtained on the spatial and temporal distribution of mercury in the organs and tissues of these fish.Cusk were obtained from 2 locations and blackbellied redfish from 4 locations. The mercury levels in both muscle and liver of cusk averaged about 0.30 ppm for one and 0.16 ppm for the second location. Gills and kidneys of cusk had mercury levels that averaged 0.08 ppm for both collections. In blackbellied redfish mercury levels in muscle and liver averaged about 0.08 ppm for all locations; gill and kidney tissues of this fish were less than 0.2 ppm.Spiny dogfish were obtained from 5 areas. No significant difference in mercury levels was found in muscle tissue as related to geographic area. Mercury levels ranged from 0.21 to 0.62 ppm. The kidneys of dogfish contained about 54% of the mercury level of muscle. The mercury level in gills of dogfish ranged from 0.06 to 0.21 ppm.Spiny dogfish pups were obtained from 6 adult females. Samples of muscle, liver, gill, kidney, and yolk of pups were analyzed for mercury. These same samples, except for the yolk, were obtained from the adult females. Mercury levels in all pup samples were less than 0.03 ppm, while mercury levels in adult females ranged from 0.03 to 1.1 ppm in all tissues and organs.     

Relationship between mercury concentrations in the blood with that in the muscle of four estuarine tropical fish species, Rio de Janeiro State, Brazil

The aim of this work was to assess the relationship between mercury concentrations in the blood with that in muscle for non-invasive mercury contamination assessment in fish. At Ribeira Bay were collected 198 fishes of 4 species (Genidens genidens, Arius luniscutis, Haemulon steindachneri, Micropogonias furnieri). At Guanabara Bay were collected 84 fishes of 2 species (Genidens genidens, Micropogonias furnieri). Means of mercury concentrations in fish muscles in both areas were below 500 ng/g. The mean ratio, including all specimens of all species, for mercury in muscle-to-whole blood was 13.4:1, for muscle-to-erythrocytes, 6.5:1 and for erythrocytes-to-plasma, 6.5:1. Further studies are necessary to insure that blood could be used as an exposure biomarker, in order to assess mercury availability in aquatic ecosystems.     

Concentrations of Mercury and Other Toxic Elements in Orange Roughy, <Emphasis Type="Italic">Hoplostethus atlanticus</Emphasis>, from the Mid-Atlantic Ridge

Concentrations of the elements mercury, arsenic, cadmium and lead were measured in the muscle tissue of Orange roughy (Hoplostethus atlanticus) obtained from the Mid-Atlantic Ridge during the Mar-Eco expedition in the North Atlantic Ocean in 2004. The age of the fish varied from 1 to 139 years. To the best of our knowledge, the concentration of the heavy metals presented here is for one of the oldest fish in the literature, in addition to the fact that very little information on arsenic in Orange roughy has been previously published. The concentration of mercury in the fillet of the fish varied between 0.06 and 1.1 μg g⁻¹ w.w. Mercury was the only element that was positively correlated to the age. The concentrations of mercury were found to be below the maximum limits for Orange roughy set by EU at 1.0 μg g⁻¹ w.w, except for a 134 year fish sample with a concentration of 1.1 μg g⁻¹ w.w.     

Total and organic mercury in ten fish species for human consumption from the Mexican Pacific

Total mercury and organic mercury were measured in ten fish species from the Mexican Pacific ocean to have a general view on the ratio of total mercury-organic mercury and potential implications on human health. Highest concentration of total mercury was recorded in muscle tissue of Carcharhinus leucas (0.62 μg g⁻¹ wet weight). Organic mercury was more concentrated in Haemulon sexfasciatum (0.4 μg g⁻¹ wet weight). Percentages of organic mercury ranged from 33 to 100%. Hazard indices associated to organic mercury and average fish consumption in Mexico ranged from 0.25 in Lutjanus colorado to 1.65 in Haemulon sexfasciatum.     

Heavy Metal Levels in Fish from Coastal Waters of Uruguay

Copper, mercury, and zinc levels were determined in muscle and liver (N=163) of seven fish species caught in coastal waters off Montevideo and Piriápolis (control site): Odontesthes spp., Mugil platanus, Micropogonias furnieri, Urophycis brasiliensis, Cynoscion guatucupa, Menticirrhus americanus, and Mustelus schmitti. The local population commonly uses these species for consumption. Heavy metal concentrations determined in this study were generally below those obtained for fish caught in Argentinean and Brazilian coastal waters, with some exceptions in the case of mercury and zinc. Based on copper, mercury, and zinc levels in muscle tissue, we conclude that the fish studied here are acceptable for human consumption. Nevertheless, it is recommended not to consume the fish liver (up to 466 g Zn g^–1 dry weight in liver) nor large specimens of the investigated species. Regional programs involving the neighboring countries should be established to assess the fisheries resources and potential risks for human health.     

Chronic accumulation of cadmium in the edible tissues of Oreochromis aureus (Steindachner): Modification by mercury and lead

The influence of mercury and lead on cadmium accumulation was investigated by exposing the fish Oreochromis aureus, or Blue Tilapia, to two heavy metals simultaneously. The chronic accumulation profile of cadmium in the liver, brain, gill filaments, intestine, caudal muscle, spleen, trunk kidney, and gonads was determined for exposure to cadmium alone and with lead or mercury. O. aureus was exposed to cadmium alone at 0.05 and 0.10 mg/L, and mixtures of 0.05 mg/L cadmium with 0.05 mg/L mercury or lead (0.05 and 0.50 mg/L). Little research has previously been carried out on the long-term interaction between these heavy metals and their effects on tissue accumulation of heavy metals. In a food fish such as O. aureus, a knowledge of toxic metal accumulation patterns is of great importance. The highest levels of cadmium were consistently accumulated by the kidney, and the presence of other mercury or lead did not change this trend. The spleen, intestine, and liver also accumulated high levels of cadmium, while the caudal muscle and brain accumulated the lowest levels of cadmium. Separating the viscera fom the muscle would therefore reduce the cadmium burden of fishmeal.