Heavy metals in Baltic herring and cod

The monitoring programme of harmful substances in selected species in the Baltic Sea was started in 1979. In the present study, three-year averages of Zn, Cu, Cd and Pb in cod liver (Hg in cod muscle) and herring muscle are reported. The concentrations of heavy metals in cod show areal differences roughly in accordance with the concentrations of heavy metals in sea water. No significant differences between heavy metal concentrations in North Atlantic and Baltic Sea species were found, except for mercury, for which values in the Baltic Sea species are lower than in those from the North Atlantic.     

Indicator Tissues for Heavy Metal Monitoring – Additional Attributes

Preferred characteristics of biological indicators for heavy metal monitoring in marine ecosystems were documented 30 years ago. Heavy metal data from Raine Island on the outer-northern Great Barrier Reef are presented to introduce additional attributes for consideration, including a widened choice of biological tissues due to advances in trace heavy metal analysis. Kidney tissues, visceral mass and adductor muscle from the giant clam (Tridacna maxima), muscle tissue from trochus (Trochus niloticus) and axial muscle from four species of fish were targeted. The kidneys of giant clams had concentrations of heavy metals from 2 (Zn) to 2780 (Ni) times higher than corresponding concentrations in adductor muscles. Also, tissues of giant clam and the muscle of trochus gave different signals with respect to bio-available heavy metals. Linear correlations for heavy metals within and between tissues of giant clam and within muscle tissue of trochus, offer opportunities for the use of surrogates as well as a possible mathematical basis for assessing trends in heavy metal pollution.     

Heavy metal residues in tissues of marine turtles

Heavy metal concentrations in the tissues of marine turtles are presented. The most frequently monitored elements are mercury, cadmium and lead; and the tissues mainly analysed in nearly all the stranded individuals are muscle, liver and kidney. The highest mercury and cadmium levels were found in liver and kidney respectively; the majority of the lead burden existed in bones and carapace, while arsenic was present mainly in muscle tissue. Mercury occurred quite completely as methylmercury in muscle, whereas in liver the main form was the inorganic one. Arsenic was exclusively present in the metallorganic form either in muscle tissue or in liver. Metals in the eggs were mainly present in the yolk. Significantly higher concentration of mercury, copper, zinc and iron were found in yolk than albumen, while shell contained highest levels of manganese and copper. The load of trace metals in these animals strictly correlated with the species seems to depend on their different food behaviour.     

Metal tissue levels in Steller sea lion (Eumetopias jubatus) pups

The endangered Western population of the Steller sea lion declined for three decades for uncertain reasons. We present baseline data of metal concentrations in pups as a first step towards investigating the potential threat of developmental exposures to contaminants. Seven metals were investigated: arsenic, cadmium, silver, aluminum, mercury, lead and vanadium. Vanadium was detected in only a single blubber sample. Mercury appears to be the most toxicologically significant metal with concentrations in the liver well above the current action level for mercury in fish. The concentrations of aluminum, arsenic, silver, cadmium and lead were present in one-fourth to two-thirds of all samples and were at either comparable or below concentrations previously reported. Neither gender nor region had a significant effect on metal burdens. Future work should consider metal concentrations in juveniles and adults and toxicological studies need to be performed to begin to assess the toxicity of these metals.     

Tissue distribution of heavy metals in Weddell seals (Leptonychotes weddellii)

Tissue distributions of heavy metals were investigated in the Weddell seal collected around Syowa Station, Antarctica. Generally, the metal concentrations were high in liver and kidney and low in brain, blubber and skin. Fe in blood and spleen, Zn in bone, and Mn and Cd in pancreas and gastrointestinal organs were also relatively high. Wide variations of the metal concentrations in different bones were also observed. The concentrations of Fe and Cd were positively correlated with moisture content of the bones, while those of Mn and Zn increased with increase of Ca content in the bone. Majority of the metal burden in the body existed in muscle and liver. A relatively high burden of Cd was in the kidney. Based upon these results, the suitability of the tissues of a seal for ecological and toxicological comparisons is discussed.     

The potential use of fairy prions (Pachyptila turtur) as monitors of heavy metal levels in Tasmanian waters

The purpose of the present study was to examine the potential use of the fairy prion to monitor contamination in the marine food chain following ocean dumping of industrial waste in S.E. Tasmania. Factors considered that can complicate interpretation of heavy metal levels detected include age, sex, seasonal, and other ecological aspects of the indicator species chosen. Unlike some other species of seabirds, the influence of sex and season on metal levels was unimportant. Copper, zinc, cadmium, and lead were tested in the liver and muscle tissue of fairy prions. In this preliminary study, cadmium levels were found to be significantly higher statistically in fairy prions closest to a potential source of pollution compared to levels from distant locations. This trend was not found in other metals investigated. However, it is suggested that this species would provide a useful future means of monitoring heavy metal levels.     

Metal Concentrations in Tissues of Rabbitfish (Siganus oramin) Collected from Tolo Harbour and Victoria Harbour in Hong Kong

Rabbitfish (Siganus oramin, also known as Siganus canaliculatus) samples were collected from different coastal sites in the Victoria Harbour and Tolo Harbour in the summer of 1997 for the analyses of metal (cadmium, copper, lead, and zinc) concentrations in liver, gills, and muscle. The overall metal concentrations in rabbitfish tissues were below regulatory levels implemented through the government of Hong Kong. For cadmium and lead, the metal concentrations detected were place concentrations here. Generally speaking, the metal concentrations in liver samples were higher than that of gills and muscle. However, the mean values of lead concentrations of rabbitfish from the Tolo Harbour and Victoria Harbour are higher in the gills than in the livers.     

Mercury concentrations in stomach contents and muscle of five fish species from the north east coast of England

Mercury concentrations in stomach contents and muscle tissue are reported for five fish species: herring (Clupea harengus), whiting (Merlangius merlangus), roker (Raja clavata), plaice (Pleuronectes platessa) and dab (Limanda limanda) collected in summer 1992 off the mouth of the River Tyne, North East England. Median muscle mercury concentrations in the area increase in the order plaice < herring < roker < dab < whiting. Absolute mercury concentrations and muscle mercury-length relationships indicate that the environmental availability of mercury in the study area is low. Stomach contents were recovered from dab, plaice and roker only. Median mercury concentrations in stomach contents increased in the order plaice < roker < dab. The variability of the ratio (muscle mercury/stomach content mercury) has been examined for these three species. In dab the variation is relatively low (39.7% RSD), whereas in plaice and roker it is considerably higher (128.4% and 184.6%, respectively). If stomach content mercury concentrations accurately reflect local mercury availability then dab muscle tissue would make a more reliable availability index than muscle tissue of plaice or roker.     

Bioaccumulation of Sediment-Bound Heavy Metals in Grey Mullet, Liza macrolepis

Two groups of grey mullet, Liza macrolepis, a filter and a detritus-mud feeder, were chosen as the subjects of a sediment exposure experiment for evaluating the bioaccumulation of toxic metals associated with the Kaohsiung-harbour sedimental contamination. After 180 days of sediment exposure, the sediment treated group showed significantly elevated Cu, Mn, Fe, Zn and Cd concentrations in whole fish at 3-, 1.5-, 3-, 2-, and 2-times, respectively, higher than the control group. The Ni concentrations were not significantly different between the two groups. The metal levels (Cu, Mn, Fe, Zn, and Cd) in various parts of the fish showed that all metals in muscle and gill, Cu in liver, and Zn in intestine and liver of the sediment-treated group were significantly higher than those of the control group. The bioaccumulation factors (BAFs) in whole fish ranked as Cd > Zn > Cu > Mn > Ni > Fe. The results of significant bioaccumulation suggest that L. macrolepis can be used as a good bio-indicator of metal pollution in coastal area.     

Metal concentrations in selected tissues and main prey species of the annulated sea snake (Hydrophis cyanocinctus) in the Hara Protected Area, northeastern coast of the Persian Gulf, Iran

This study is the first detailed ecotoxicological study of the annulated sea snake, Hydrophis cyanocinctus. Concentrations of lead, cadmium, nickel and vanadium were evaluated in muscle, liver, kidney, skin and blood of the annulated sea snake (H. cyanocinctus) and in the whole bodies of its main prey species (Periophthalmus waltoni and Boleophthalmus dussumieri) in the Hara Protected Area, the Persian Gulf. The mean concentrations of lead and vanadium were highest in the kidney, which identified the kidney as a target organ for metals in sea snakes as it is in other reptilian groups. Mean concentrations of cadmium and nickel were highest in the liver and skin, respectively. Mean cadmium concentrations were significantly higher in the liver compared to prey species, which indicated that prey items may be a source of cadmium for the annulated sea snake in the study area. Data presented here may be considered as a baseline for further ecotoxicological studies in sea snakes.     

Spatial and temporal distribution of heavy metal concentrations in mussels (Mytilus edulis) from the Baie des Chaleurs, New Brunswick, Canada

Previous studies on heavy metal contamination of the Baie des Chaleurs focus only on industrial centers and overlooked the ecosystem as a whole. To fill this gap, the objective of this study is to establish a baseline of the spatio-temporal distribution of heavy metals in mussels from the Baie des Chaleurs based on the ecosystem approach. Our results show, for the first time, a cadmium contamination in mussels across the south coast of the Baie des Chaleurs and not only in industrial centers. Our results also confirm previous studies showing heavy metal contamination of the Belledune area. This study demonstrates that the use of the ecosystemic approach is essential to obtain a comprehensive picture of environmental contamination in marine ecosystems.     

Influence of Mixtures of Phenols and Metals on Luminous Bacteria

The toxic action of bicomponent mixtures of phenols and heavy metals on luminous bacteria has been studied. It was established that phenolic compounds displaying properties of structural-specific agents whose influence is based on chemical reactions with receptors in mixtures with heavy metals of mercury, cadmium in low concentrations caused additive, and with the increase of metal concentration-more than additive, effects. Phenolic compounds acting as structurally-nonspecific agents (resorcinol), whose toxicity is stipulated by their physico-chemical properties, produce a less than additive effect in a mixture with heavy metals.     

Trace elements in farmed and wild gilthead seabream, Sparus aurata

In the present study, we sought to determine the concentration of several trace elements (total and organic mercury, selenium, cadmium, lead, arsenic, copper, chromium, iron, manganese, molybdenum, vanadium and zinc) in muscle tissue of gilthead seabream (Sparus aurata), an edible finfish species that is widely cultured in the Mediterranean area. The phenomenon of bioaccumulation and bioamplification (especially of mercury) was investigated by comparing farmed fish with wild specimens of the same species. Farmed specimens showed mercury and arsenic concentrations significantly lower than wild specimens, and no relationship was found between mercury concentration and body size. The lower level of methylmercury in farmed fish has important implications for consumer health.     

Accumulation of heavy metals to assess the health status of swordfish in a comparative analysis of Mediterranean and Atlantic areas

During the last few decades, the combined effects of natural and human activities acting on the Mediterranean Sea basin have caused a reduction in the swordfish (Xiphias gladius, L. 1758) population. In this project, we investigated the accumulation of lead (Pb), cadmium (Cd) and mercury (Hg) levels in the Atlantic and Mediterranean populations of swordfish during a five-year survey. In the marine environment, top predators such as swordfish accumulate high concentrations of toxic metals, and thus, potentially incur a high toxicological risk. Furthermore, heavy metals, such as chemical pollutants, have strong long-term effects on fish, and thus, constitute a high risk for the resource and humans that consume it. The aim of this work is to contribute to the assessment of the state of European swordfish population health. We analyzed muscle tissue from 56 specimens captured in Mediterranean and Atlantic areas for trace elements. Mean concentrations of Hg, Cd, and Pb were in the following ranges: 0.66-2.41, 0.04-0.16, and 0.97-1.36 mg/kg ww, respectively. These data suggest a need for continuous monitoring to avoid reductions in the population of this fish species of high commercial and ecological interest.     

Trace metals in tissues of gray whale (Eschrichtius robustus) carcasses from the Northern Pacific Mexican Coast

Samples of liver, lung, heart, muscle, and blubber tissue from the carcasses of juvenile gray whales (Eschrichtius robustus) found stranded on the coast off the Sea of Cortez, México were analyzed for a range of trace metals (Cu, Fe, Zn, Mn, Ni, Pb, and Cd). The highest concentrations of copper, iron, zinc, and manganese were found in liver; nickel and lead in heart, and cadmium in kidney. In all tissues analyzed, iron, zinc and copper were present in the highest concentrations; however, some whales also showed high levels of cadmium in the kidney which could be related to their diet. Elevated concentrations of copper were found only in the liver of one whale. In general, where low levels of iron were found in the liver, they were associated with poor nutrition. Lead, nickel, manganese and zinc levels in liver were within the normal range, indicating that these whales had not been exposed to high levels of these metals.     

Selenium and heavy metals in black marlin

Black marlin from the apparently unpolluted waters off north-eastern Australia have the highest muscle and liver concentrations of total mercury yet reported for a teleost species. Selenium concentrations are also high. There is a significant correlation between mercury and selenium concentrations, and concentrations of both those elements are significantly correlated to size of fish. Concentrations of cadmium, lead, zinc, copper or arsenic are not so correlated.The results of this study indicate there is a need for a moratorium on the use of this species for human consumption.     

Bioaccumulation of Cadmium, Copper and Zinc in some Tissues of Three Species of Marine Turtles Stranded Along the French Atlantic Coasts

Cadmium, copper and zinc have been analysed in some tissues and organs of Loggerhead, Kemp’s Ridley (only muscle for this species) and Leatherback turtles stranded along the Atlantic coasts of France. The pancreas analysed only in Leatherback turtles exhibited the highest metal concentrations, which is very surprising for an organ which does not play a role in the detoxification processes. The distribution of these elements in kidney, liver and muscle were quite similar to that found in marine mammals or seabirds. Nevertheless, mean cadmium concentrations in the kidney were as high as 13.3 μg g⁻¹ wet weight in the Loggerhead turtles and 30.3 μg g⁻¹ wet weight in the Leatherback turtles. Such high concentrations in the Leatherback turtles have never been recorded before. The main source of cadmium for marine turtles is probably the food. The Leatherback turtles are known to feed mainly on jellyfish in this area. Ten times higher cadmium concentrations have been determined in jellyfish compared to fish. This would imply a greater exposure to cadmium for Leatherback turtles, which probably need to eat great quantities of jellyfish to cover their needs.     

Age-related change and distribution of cadmium and zinc concentrations in the Steller sea lion (Eumetopias jubata) from the coast of Hokkaido,Japan

Tissue cadmium and zinc levels in Steller sea lions have been analysed to elucidate the body distribution of these metals and their age-related accumulation. A significant correlation between age (0.7–8.8 year old) and renal and hepatic cadmium concentration was noted. Of the tissues examined, the kidney manifested the highest cadmium content (mean: 20.9 μg g^?1 dry wt). A similar zinc distribution pattern was observed; its concentration was more uniform among tissues than that of cadmium. The tissue cadmium concentration in the Steller sea lion was lower than in other pinnipeds from various areas, possibly due to their feeding habits which may represent a major pathway of metal accumulation.     

Distribution and abundance of heavy metals in finfish,invertebrates and sediments collected at a deepwater disposal site

Analyses of deep water finfish to several heavy metals indicate that deep water fish have less metal in muscle tissue than do fish taken from the continental shelf. Liver tissue from deep water fish also, generally, contain less metals. Sediments and a single invertebrate collected at deep water stations have also been analysed for heavy metals.     

Levels of Cd,Cu, Pb and V in marine sediments in the vicinity of the Single Buoy Moorings (SBM3) at Mina Al Fahal in the Sultanate of Oman

Recently in the Sultanate of Oman, there has been a rapid surge of coastal developments. These developments cause metal contamination, which may affect the habitats and communities at and near the coastal region. As a result, a study was conducted to assess the level of metal contamination and its impact on the marine sediments in the vicinity of the Single Buoy Moorings 3 (SBM3) at Mina Al Fahal in the Sultanate of Oman. Marine subtidal sediment samples were collected from six different stations of the SBM3 for the period ranging from June 2009 to April 2010. These samples were then analyzed for their level and distribution of the heavy metals of cadmium (Cd), copper (Cu), lead (Pb) and vanadium (V). Overall, low concentrations of all four heavy metals were measured from the marine sediments, indicating that the marine at SBM3 is of good quality.