Heavy metals contamination in water and three species of most consumed fish sampled from Caspian Sea, 2011

The present study is an attempt to evaluate the heavy metal contamination in the marine environment of the Caspian Sea of Iran. The concentrations of zinc, chromium, cadmium, and lead were measured in water and dorsal muscle of fish sampled from 10 selected stations along Gorgan coast using atomic absorption spectrophotometry during summer of 2011. The average concentrations of lead in water and fish samples (115.29?±?14.78 and 113.23?±?27.01 μg/L) were significantly higher than that of cadmium and chromium (P?<?0.05). The highest heavy metals content was observed in Cyprinus carpio samples. The heavy metals concentrations in the samples were within the acceptable recommended standards. But, elevating levels of heavy metals in water and fish made a serious concern about ecosystem and food chain contamination. It is recommended that protective authorities should carry out a continual assessment on the levels of pollutants in the sea.     

Sediment pollution by heavy metals in the Strymonikos and Ierissos Gulfs,North Aegean Sea,Greece

Surface sediment samples from Strymonikos and Ierissos Gulfs wereanalyzed for Cu, Pb, Zn, Cr and Ni. The results showed that the sediment of Ierissos Gulf is more polluted with Cu, Pb, and Zn ascompared to that of Strymonikos Gulf. The benthal area located off the load-out facility of the mining operations in the town of Stratoni, in Ierissos Gulf is established as the most pollutedregion. The distribution of Cr and Ni in both gulfs indicates thenatural origin of these metals with the weathering of Strymon River and of other smaller rivers rocks being responsible for their enrichment.     

Determination of heavy metals in fresh water fish species of the River Ravi, Pakistan compared to farmed fish varieties

The untreated industrial and sewage wastes arising from industries and metropolitan activities make their passage to the River Ravi, Pakistan, where Balloki Headworks is one of the major sites of effluent concentration. This study was designed to evaluate the concentration of various toxic elements in fishes of that area compared to a nearby fish farm. The concentrations of heavy metals, such as As, Cd, Cu, Pb, Hg, and Zn, and electrolytes Ca, K, and Na were determined in different edible and non-edible fresh water fish varieties. Fish samples were collected from two selected sites and were analyzed for aforementioned elements. Higher levels of As (35.74–45.33 ppm), Cd (0.35–0.45 ppm), Pb (2.1–3.0 ppm), Hg (83.03–92.35 ppm) while normal levels of Zn (37.85–40.74 ppm) and Cu (1.39–2.93 ppm) were observed. Mercury, higher levels of which trigger cough, impairment of pulmonary function, and psychotic reactions, was significantly higher in all studied categories. At the sites under study, there has been observed alarming levels of toxic metals which are needed to be monitored regularly.     

Summer distribution of trace metals in the western sector of the Ross Sea, Antarctica

The more important water masses generated by the interaction of Circumpolar Deep Water and the shelf waters in the western sector of the Ross Sea are characterized for trace element contents. The distribution of cadmium, lead, copper, zinc, iron, manganese and chromium during the austral summer is analysed and discussed according to the physical, chemical and biological processes which affect the composition of the water masses. The Cd concentration is found to have a relative high variability that can be related to biological activity and the water mass age, MCDW presents a mean dissolved concentration (SD) of 0.77 (0.07) nmol kg(-1), while the HSSW and AASW have a mean concentration of 0.63 (0.06) and 0.61 (0.16) nmol kg(-1), respectively. Lead features the typical distribution of a scavenged element with a surface maximum ranging between 22 and 130 pmol kg(-1) decreasing to 11 pmol kg(-1) in deep waters. However, the vertical distribution in the shelf area features a maximum concentration in intermediate/deep waters and we can hypothesize that the distribution may be influenced by more than one source. The surface dissolved concentration of zinc and copper were un-homogeneously distributed, the mean (SD) values were 5.25 (2.92) and 1.99 (1.49) nmol kg(-1) for zinc and copper, respectively and increased with depth for both the elements. We may therefore hypothesize enrichment in the dissolved phase deriving from recycling in deep waters. 95% of the chromium was in dissolved form and showed a superficial depletion; the mean concentrations were 1.6 +/- 0.2 and 2.6 +/- 0.8 nmol kg(-1) for surface and deep waters respectively. The vertical distribution of dissolved manganese was quite homogeneous with a mean concentration 0.96 +/- 0.7 nmol kg(-1). The particulate iron and manganese concentration trends are similar and feature a significant bottom increase implying a significant input from resuspension; the mean concentration of particulate ranged between 1.4 and 7.4 nmol kg(-1) for iron and ranged between 0.072 and 0.29 nmol kg(-1) for manganese.     

Biomonitoring of heavy metals in fish from the Danube River

The Croatian part of the Danube River extends over 188 km and comprises 58 % of the country’s overall area used for commercial freshwater fishing. To date, the heavy metal contamination of fish in the Croatian part of the Danube has not been studied. The main purpose of this study was to determine heavy metal levels in muscle tissue of sampled fish species and to analyze the measured values according to feeding habits of particular groups. Lead ranged from 0.015 μg^?1 dry weight in planktivorous to 0.039 μg^?1 dry weight in herbivorous fish, cadmium from 0.013 μg^?1 dry weight in herbivorous to 0.018 μg^?1 dry weight in piscivorous fish, mercury from 0.191 μg^?1 dry weight in omnivorous to 0.441 μg^?1 dry weight in planktivorous fish and arsenic from 0.018 μg^?1 dry weight in planktivorous to 0.039 μg^?1 dry weight in omnivorous fish. Among the analyzed metals in muscle tissue of sampled fish, only mercury exceeded the maximal level (0.5 mg kg^?1) permitted according to the national and EU regulations determining maximum levels for certain contaminants in foodstuffs, indicating a hazard for consumers of fish from the Danube River.     

Impacts of the fish farms on the water column nutrient concentrations and accumulation of heavy metals in the sediments in the eastern Aegean Sea (Turkey)

Pulp and paper mill effluents may cause harmful effects to the aquatic environment due to the combined influence of physical factors, toxic compounds, and nutrient enrichment. In the present study, the effectiveness of secondary treatment in reducing the toxicity of an elemental chlorine-free bleached-kraft pulp mill effluent was evaluated. To characterize the toxicity of the effluent, before and after the implementation of secondary treatment, a battery of tests with organisms bearing different functions at the ecosystem level was used, namely Vibrio fischeri (5-min luminescence), Pseudokirchneriella subcapitata (72-h growth), Lemna minor (7-day growth), Daphnia magna (21-day reproduction and 24-h postexposure feeding), Chironomus riparius (9-day growth), and Danio rerio (28-day growth). For the effluent sample collected before the implementation of secondary treatment, P. subcapitata was the most sensitive organism followed by V. fischeri and D. magna, and no toxic effects were observed toward the other organisms. For the effluent sample collected after the implementation of secondary treatment, the effluent caused no toxic effects on any of the tested species. The present results demonstrated not only that secondary treatment efficaciously reduced effluent toxicity toward the selected test organisms but also the usefulness of a battery of tests to characterize the toxicity of pulp mill effluents.     

Distribution of heavy metals in surface sediments from the South China Sea ecosystem, Malaysia

The concentrations of arsenic, cadmium, chromium, copper, mercury, nickel, lead and zinc in surface sediments collected from the east coast of peninsular Malaysia, along the South China Sea, were measured by two methods instrumental neutron activation analysis and inductively coupled plasma mass spectroscopy. The obtained results were use to determine the areal distribution of the metals of in the east coast of peninsular Malaysia and potential sources of these metals to this environment. The geochemical data propose that most of the metals found in the east coast of peninsular Malaysia constitute a redistribution of territorial materials within the ecosystem. Then, the metal concentrations can be considered to be present at natural background levels in surface sediments.     

Analysis of some heavy metals in the riverine water, sediments and fish from river Ganges at Allahabad

The river Ganges has been one of the major recipients of industrial effluents in India. The present paper deals with the study related to occurrence and bioaccumulation of heavy metals (Cu, Cr, Cd, Pb, Zn) in the riverine water, sediment, and the muscles of two cat fish species, Channa punctatus (C. punctatus) and Aorichthys aor (A. aor) procured from the river Ganges at Allahabad. The data obtained after water analysis reflected the order of occurrence of heavy metals to be Zn > Pb > Cu > Cr > Cd, respectively. The analysis of heavy metals in sediment indicated that among the five heavy metals tested; Zn was maximally accumulated followed by Pb, Cr, Cu and Cd. The trend of heavy metals accumulation in fish muscles was found to be similar to that observed in sediment and water such as Zn > Pb > Cu > Cr > Cd. Data indicated that Zn accumulated maximally in the sediment as well as muscles of both of the fish species in comparison to other metals.     

Assessment of the exposure of two fish species to metals pollution in the Ogun river catchments, Ketu, Lagos, Nigeria

The concentrations of metals (Ca, Cd, Fe, Mn, Pb and Zn) were determined by flame atomic absorption spectrophotometry in water, sediments and fish samples in the Ogun river catchments, Ketu, Lagos, which is an important bird nesting, fishing and drinking water source. The results show that the southern tip bothering the Lagos lagoon is where the highest metal concentrations are found in the fish species (Tilapia sp. and Chrysichthys sp.), whereas the Agboyi creek segment near the lagoon with higher surrounding human population density recorded higher levels of metals in sediments and water samples. The two fish species accumulated different amounts of metals. However, the differences were not statistically different at p < 0.05. There is a significant correlation (p < 0.05) for Cd concentration in water. The concentrations of Pb in sampling points 3 and 4 as well as Cd, Mn and Fe in all six sampling points exceeds the World Health Organization (WHO) limits for drinking water. Levels of metals obtained for sediments are within the range reported for Nigeria’s river sediments. Based on this study, the human risks for heavy metals in the harvested fish species from the Ogun river catchments, Ketu, are low for now as the concentrations were below the recommended Food and Agriculture Organization (FAO) maximum limits for Pb (0.5 mg/Kg), Cd (0.5 mg/Kg), and Zn (30 mg/Kg) in fish.     

Biological effects monitoring of the North Sea employing fish embryological data

Using the reproductive capacity of fish appears to be a suitable approach for risk assessment in the aquatic environment since fish are a typical representative thereof and in addition they are of considerable societal value. Generally the early embryonic stages are considered to be one of the most sensitive parts of a fish's life cycle. A method has been developed to use the state of health of live, naturally spawned fish embryos from plankton samples for biological effects monitoring. During the years 1985–1987 in the southern North Sea and in 1991–1992 in the whole of the North Sea fish eggs were sampled from surface waters and examined for developmental abnormalities. Elevated embryo malformation rates were detected in the plume of the major rivers Elbe and Rhine as well as along the eastern coast of England. Occurring malformations are thought to be pollution-related and may be used to define areas of environmental deterioration. The method is discussed in view of its suitability for biological effects monitoring using malformations in fish embryos as biomarkers.     

Assessment of PAH pollution in the southern Baltic Sea through the analysis of sediment, mussels and fish bile

The concentrations of fifteen PAH compounds in samples of sediment and blue mussel tissue (Mytilus trossulus) were measured. In addition, the biliary polycyclic aromatic hydrocarbon metabolites present in flounder (Platichthys flesus) were analysed. Two methods were used in the analysis of PAH metabolites; high performance liquid chromatography (HPLC) and fixed wavelength fluorescence (FF). The major PAH metabolite which could be measured using the HPLC method was 1-OH pyrene. It was possible to detect 1-OH Phe and 3-OH B[a]P in 70 and 24 samples respectively, of the 87 samples analysed. However, the concentrations of 1-OH Phe and 3-OH B[a]P were below or near to the LOQ (0.002 μg ml(-1) bile). The bile of flounder samples from the Gulf of Gdańsk had 1-OH Pyr concentrations which ranged from 0.019 to 0.066 μg ml(-1) bile. The high linear correlation observed between the quantity of 1-OH pyrene determined by the HPLC-F method and the content of the sum of pyrene-type PAHs obtained by the FF method indicated the FF method of determination of pyrene-type PAH metabolites can be used as a screening method. The content of ∑(15)PAHs in sediments collected in the Gulf of Gdansk, in 2008, ranged from 29.3 to 103 μg kg(-1) dw. In mussel tissue ∑(15)PAHs concentrations were between 173.2 μg kg(-1) dw and 237.7 μg kg(-1) dw. All concentrations measured in the current study, in mussel tissue, were below the OSPAR toxicity threshold values.     

Seasonal variation of Sarpa salpa fish toxicity, as related to phytoplankton consumption, accumulation of heavy metals, lipids peroxidation level in fish tissues and toxicity upon mice

The aim of this work was to investigate for Sarpa salpa the seasonal trend in the food sources, heavy metals bioaccumulation and the oxidative stress in the organs. In addition, the toxicity was assessed by mouse bioassay of extract of the fish's organs collected in autumn, the peak of occurrence of hallucinatory syndrome. The toxicity was further studied for compounds present in epiphyte collected from the sea at the end of spring and in summer that are digested by the S. salpa in these seasons. We observed a higher lipid peroxydation in different tissues of S. salpa compared to the control fish Diplodus annularis. Furthermore, heavy metals accumulation in organs of these fish showed a significant variation between the two species (P?<?0.05). The lethal dose (LD50%) determined for crude ciguatoxin (neurotoxins) extracts of viscera, liver, brain and muscle of S. salpa were as follows: 1.217, 2.195, 14.395, 18.645 g/kg mouse, respectively. We noticed a significant correlation (P?<?0.05) between the total amount of toxic dinoflagellates and the level of TBARS in the liver, the brain and the muscle, this for all seasons and all sizes. Moreover, the cytotoxic effect observed for epiphytes extract confirms the transfer of toxins originating from toxic dinoflagellates, which live as epiphytes on P. oceanica leaves, to the fish by grazing. Our work indicates that, toxic phytoplanktons and heavy metals accumulation are responsible for the increase of oxidative stress in the organs of S. salpa. Hence, the edible part of S. salpa, especially the viscera and liver, can cause a threat to human health, and consumption should, for this reason, be dissuaded.     

Analysis of heavy metals in marine fish from Mumbai Docks

Seafood containing heavy metals as a result of environmental contamination causes toxicity in human beings. To evaluate such kind of contamination, our study targeted the analysis of metals such as lead, copper, cadmium, mercury, and arsenic in muscle tissue of the fish. The fish commonly consumed such as Brama brama (Pomfret), Rachycentron canadus (Surmai/King Fish), Rastrelliger kanagurta (Mackerel), Eleutheronema tetradactylum (Ravas/Indian salmon), and Metapenaeus monoceros (Brown Prawn) were collected from four different docks in the city. The heavy metals in tissue samples of fish were estimated using voltammeter and cold vapor atomic absorption spectrophotometer. Heavy metal concentration in the tissues varied significantly depending upon the locations from where the fish were collected. Although the concentration of arsenic, copper, cadmium, and lead were in normal range, the concentration of mercury was found to exceed the daily permissible levels (1 μg/g) as a food source for human consumption. We have analyzed heavy metals from different locations in Mumbai—Versova dock, Sassoon dock, Navi Mumbai dock, and Mazgaon dock.     

Distribution of heavy metals in plants and fish of the Yamuna river (India)

The distribution of cadmium (Cd), cobalt (Co), chromium (Cr), copper (Cu), iron (Fe), manganese (Mn), nickel (Ni), lead (Pb) and zinc (Zn) in the plants and fish of Yamuna river from Delhi to Allahabad, a distance of about 840 km, at five sampling stations was determined in the year 1981. The results have shown wide variations in the heavy metal levels from one sampling station to the other. The concentrations of Cd, Co, Cr, Cu, Fe, Mn, Ni, Pb, and Zn in the plants (Eicchornia crassipes) were found to be 0.02–0.12, 2.7–21.3, 4.6–64.8, 9.8–114.0, 193.0–1835.0, 380.0–1443.0, 4.4–83.0, 4.8–30.2, and 22.1–356.5 g g^-1 respectively whereas in the fish (Heteropnuestes fossilis) were found to be ND-0.40, 2.3–13.7, 3.7–26.9, 8.33–58.1, 278.3–1108.0, 81.3–213.8, 2.8–32.7, 1.4–12.8 and 101.8–364.8 gg^-1 respectively on dry weight basis.     

Variation characteristics and ecological risk of heavy metals in the south Yellow Sea surface sediments

Eight cruises were conducted on the south Yellow Sea (SYS) from 1998 to 2005. Variations and the potential ecological risk of heavy metals were studied using the survey data collected during October 2003. The metal content (except for As) was high in the central area where the fine grain size sediments were dominant, and low inshore area where more coarse sediments were present. This suggested that grain size was important in determining distributions of heavy metals. In some local areas, other influencing factors, such as organic content, sedimentation rate, burial efficiency and metal's existing form were discussed. The annual averages of metals showed a stable trend with appreciable fluctuations in 8 years. Using potential ecological risk index (E (RI)) to evaluate the integrated pollution effect of heavy metals, 38.7% of the investigated area was in a moderate degree of contamination, while 77.8% was under moderate ecological risk. However, no distinct correlation was found between E (RI) and plankton biomass. In conclusion, the sediment quality of SYS was good, and the ecological risk was low in general.     

Bioaccumulation factors and multivariate analysis of heavy metals of three edible fish species from the Barekese reservoir in Kumasi,Ghana

The Barekese reservoir has seen persistent degradation for decades through anthropogenic activities within its catchment. In spite of this, heavy metal pollution profile of fish species of the reservoir is not well studied. Total concentrations of Hg, Cd, Ni, and Cr were analyzed in muscle tissues of 45 edible fish species comprising (Tilapia zilli, Oreochromis niloticus, and Heterotis niloticus) from the reservoir. The examined fish species showed varying bioaccumulative factors for detected metals. A PCA biplot revealed that Cd showed association with all examined fish species used in the study indicating that Cd in the reservoir is biologically available for uptake by all examined fish species. A dendrogram of cluster analysis also revealed that Cd and Cr are in one cluster indicating their associations and similarities to a common anthropogenic source. The study suggests that anthropogenic activities are possible sources of heavy metal pollution in the Barekese reservoir and, hence, the examined fish species could be used to monitor the levels of Ni, Cr, Hg, and Cd in the reservoir.     

Biomass and number of fish impinged at a nuclear power plant by the Baltic Sea

The main aim of this study was to investigate the number and biomass of impinged fish at Forsmark Nuclear Power Plant in Sweden, located on the coast of the Baltic Sea. Of particular interest was the number of impinged individuals of the critically endangered European eel (Anguilla anguilla) which is regularly caught in the cooling system. Another aim was to determine the comparability of the results from Forsmark and results from impingement studies in other types of waters. Cross-systems studies make it possible to (1) estimate fish loss at plants where fish is not counted, and (2) to predict changes in fish loss from changes in electricity production or cooling water use. In 2010, 31,300,000 fish with a total biomass of 62,600 kg were impinged at Forsmark. In 2011, 27,300,000 fish weighing 38,500 kg were impinged. The maximum peak in total fish number and biomass occurred in spring. The most critical period for herring was in late summer and early autumn. Regarding eel, the largest impingement losses were recorded in November. The number of fish agreed with earlier established quantities of impinged fish in both freshwater and marine ecosystems. The study also estimated that 1,300 critically endangered eels could survive at Forsmark each year if a fish return system would be constructed to allow the passage of fish from the plant back to the Baltic Sea.     

Accumulation of trace metals in the muscle and liver tissues of five fish species from the Persian Gulf

In this study, concentrations of 16 elements were quantified in muscles and livers of 141 fishes belonging to five commercially species. It was also our intention to evaluate potential risks to human health associated with seafood consumption. The grunt, flathead, greasy grouper, tiger-tooth croaker and silver pomfret fish species were obtained from Abadan, Deylam, Bushehr-Nirogah, Dayyer port, Lengeh port and Abbas port in Hormozgan, Bushehr and Khozesran provinces at the Iranian waters of the Persian Gulf. The contents of Al, As, Be, Cd, Cr, Co, Cu, Fe, Pb, Mn, Mo, Ni, Sb, Tl, V and Zn in fish muscles and livers were determined by Inductively Coupled Plasma Mass Spectrometry (ICP MS), after digestion in a CEM (Mars 5) microwave oven using nitric acid and hydrogen peroxide. Our results indicated that almost all metals were more accumulated in younger flathead, greasy grouper and tiger-tooth fishes. Contrary to the other fish species, grunt seems to stronger accumulating elements in the older fishes. Strong and positive correlations were observed in three or more of the fish species between V, Al, Fe, Tl, Co and Pb. The results confirmed that fish muscle and liver tissues appeared to be good bio-indicators for identification of coastal areas exposed to metallic contaminants. The results also showed that the element levels in the muscles of all fishes in our study were lower than the maximum allowable concentrations and pose no threat to public health, except for arsenic.     

Dinoflagellate bloom in tropical fish ponds of coastal waters of the South China Sea

Red tide of dinoflagellate was observed in brackish water fish ponds of Terengganu along the coast of the South China Sea during the study period between January 1992 to December 1992. The nearby coastal moat water facing the South China Sea is the source of water for fish pond culture activities of sea bass during the study period. An examination of water quality in fish ponds during the study period indicated that both the organic nutrients were high during the pre-wet monsoon period. The source of the nutrients in coastal water was believed to be derived from the agro-based industrial effluents, fertilizers from paddy fields and untreated animal wastes. This coincided with the peak production of dinoflagellate in the water column in October 1992. The cell count ranges from 8.3 to 60.4×10.4×10⁴/l during the bloom peak period and the bloom species were compared entirely of non-toxic dinoflagellates with Protoperidinium quinquecorne occurring >90% of the total cell count. However, both cultured and indigenous fish species were seen to suffer from oxygen asphyxiation (suffocation due to lack of oxygen). The bloom lasted for a short period (4–5 days) with a massive cell collapse from subsurface to bottom water on the sixth day. The productivity values ranged from 5–25 C g/ l / h with a subsurface maximum value in October 1992. Two species of Ciliophora, Tintinnopsis and Favella, were observed to graze on these dinoflagellates at the end of the bloom period.     

Levels of heavy metals in tissues of shingi fish (Heteropneustes fossilis) from Buriganga River, Bangladesh

Heavy metal pollution was reported in commercially valuable freshwater edible fish in the Buriganga River, Bangladesh. The concentrations of As, Pb, Cd, Cr, Zn, and Cu were investigated in the muscle, gill, stomach, intestine, and liver of Heteropneustes fossilis caught at three stations to assess the degree of fish pollution by heavy metals. Significant differences in concentrations of analyzed elements were observed among different tissues, but not among the stations. The ranges of the measured concentrations (μg/g dry weight) in the tissues of H. fossilis were as follows: arsenic concentration was (0.2–0.4), (0.82–0.90), (3.29–3.99), (2.20–2.80), and (2.41–2.90), that of lead was (1.79–2.20), (4.95–6.55), (10.36–13.38), (5.74–9.70), and (18.20–18.79), that of cadmium was (0.3–0.4), (2.87–4.27), (1.03–1.63), (1.55–4.59), and (2.25–5.50), that of chromium was (1.40–1.70), (3.52–3.72), (2.28–5.29), (2.77–3.79), and (4.25–8.65), that of zinc was (24.47–28.82), (16.82–18.80), (20.22–22.20), (22.86–26.68), and (60.82–67.80), and that of copper was (7.80–8.50), (6.22–6.81), (38.21–44.25), (17.07–21.03), and (43.24–47.30) in the muscle, gill, stomach, intestine, and liver, respectively. This research showed that the liver appeared to be the main heavy metal storage tissue, while the muscle had the lowest levels of analyzed metals. The concentrations of metal in the muscles not exceeded the acceptable levels for a food source for human consumption.