Are metal-induced hypersensitivities in harbor seals associated with liver function?

Environmental exposure to metals is believed to affect marine mammal health adversely including immunosuppression or acute as well as chronic inflammatory processes leading to hypersensitivities or autoimmune diseases. Metal-specific hypersensitivities were found in several pinnipeds of the North Sea. However, hypersensitivity is a complex phenomenon whose characteristics are still not completely understood; in particular, effects on health are not well established. In the present study, we compared basic hematological and biochemical parameters of seals with and without metal-specific hypersensitivities. We found altered hematological parameters and liver enzyme patterns in seals with a metal-induced hypersensitivity, including a reduction in macrophages, an increase in lymphocytes, and elevated levels of lactate dehydrogenase. These findings support the suggestion of a chronic influence of metal pollutants on the health of marine mammals of the North Sea.     

The Elbe flood 2002--toxic effects of transported contaminants in flatfish and mussels of the Wadden Sea

Cellular changes in livers from flounder (Platichthys flesus L.) and digestive glands of blue mussels (Mytilus edulis) were studied to analyze whether the Elbe flood catastrophe in August 2002 had any deleterious effects on animal health. Flatfish and mussels were sampled at different locations in the Elbe estuary and the Wadden Sea after the flood wave had reached the German Bight. Internationally used core biomarkers (lysosomal membrane stability, biotransformation enzymes) were applied to assess the toxic effects of putatively increased pollution levels. In comparison to earlier data from long-term studies at the same stations, we found a significant impairment in the function of cell organelles (lysosomes) involved in the detoxification and elimination of pollutants in fish liver. Concentrations of relevant contaminants (organochlorines, polychlorinated biphenyls) were analyzed in parallel with cellular biomarkers, and conspicuously raised concentrations of insecticides metabolites were detected. Cell recovery and a clear reduction in contaminant concentrations were observed in fish livers five months after the flood at all sampling sites except the Helgolander Tiefe Rinne.     

Using blood samples to estimate persistent organic pollutants and metals in green sea turtles (Chelonia mydas)

Persistent organic pollutants (POPs) and heavy metals have been reported in a number of green turtle (Chelonia mydas) populations worldwide. However, due to ethical considerations, these studies have generally been on tissues from deceased and stranded animals. The purpose of this study was to investigate the use of blood samples to estimate the tissue contamination of live C. mydas populations. This study analysed 125 POP compounds and eight heavy metals in the blood, liver, kidney and muscle of 16 C. mydas from the Sea World Sea Turtle Rehabilitation Program, Gold Coast, Australia. Strong correlations were observed between blood and tissue concentrations for a number of POPs and metals. Furthermore, these correlations were observed over large ranges of turtle size, sex and condition. These results indicate that blood samples are a reliable non-lethal method for predicting chemical contamination in C. mydas.     

Organochlorines and metals in harbour seals (Dutch Wadden Sea)

Maximum concentrations of PCB and members of the DDT family in liver, brains, kidney, spleen and heart and Cu, Pb, Zn and Cd in brains of harbour seals found dead in the Dutch Wadden Sea are higher than those reported for specimens from the German Wadden Sea, where the population is stable in contrast to the strong reduction observed for the population in the former part. Results are also compared with data from the east coast of England.     

Formaldehyde in the Elbe Estuary: Distribution and Processes

From 1989 to 1992, the concentration of formaldehyde was measured along the Elbe estuary as well as at anchor stations. In mesocosm experiments, the turnover of formaldehyde could be investigated avoiding the variability caused by tidal advection of different water bodies. Formaldehyde concentrations in the Elbe estuary ranged from 0.5… 180 μg/L. As sources, a release by algae and microbial processes were identified. Three areas with different dominance of formaldehyde turnover processes were found in the estuary. In the limnic part of the estuary, a release of formaldehyde by algae was dominant. In the mixohaline zone and the turbidity maximum, bacterial degradation of organic matter increased the formaldehyde concentration. In the mouth of the estuary, the adjacent Wadden sea areas influenced the concentration due to formaldehyde-rich runoff from the tidal mud flats. In the other parts of the estuary, a fast degradation of formaldehyde kept the formaldehyde concentration at a low level. In sediment cores from the Elbe and a mesocosm, the formaldehyde concentrations were in the same range as in the water column. Mesocosms with and without sediment showed no significant differences in concentration levels which were similar to those measured in the Elbe at the same time. During the investigated period, no anthropogenic impacts of formaldehyde into the Elbe estuary could be detected.     

Sweden

Four invertebrate and one fish species (Cerastoderma edule, Mya arenaria, Arenicola marina, Crangon crangon, Solea solea) from a single area of the German Wadden sea were investigated for concentrations of ten organochlorine pollutants in 1976. PCB concentrations (wet tissue basis) were predominating with 10–200 ng g^?1, while p,p′-DDD, dieldrin, α-HCH, γ-HCH and p,p′-DDE generally ranged between 1 and 10 ng g^?1. Values of α-endosulfan were even lower; p,p′-DDT, endrin and heptachlor epoxide could not be detected. Residue levels in shrimps were close to the lower range of values which have been found in this species from other areas of the North Sea since 1974. The patterns of residue concentrations in the five aquatic species were remarkably different indicating species- and compound-specific bioaccumulation. Trophic level and lipid content were shown to be responsible for PCB concentrations increasing from bivalves to fish.     

The dynamics of phytoplankton, bacteria and heterotrophic flagellates at two Banks near Magdeburg in the River Elbe (Germany)

The main objectives of this study were to describe the seasonal standing stock dynamics of phytoplankton, bacterioplankton and heterotrophic flagellates in the highly eutrophic River Elbe (Germany), and to compare the seasonal patterns observed with other streams. Emphasis was placed on examining and assessing abiotic and biotic controlling factors influencing the structure and dynamics of the riverine plankton. All the physico-chemical and biological parameters determined were within the range or somewhat higher (in the case of phytoplankton abundance and biomass) than reported for other large streams. The underwater light conditions resulting from atypically short phytoplankton growth periods of about 6 months per year and the low phytoplankton carbon to chl a ratio of 23 were identified as a major limiting factor for phytoplankton development in the River Elbe. The seasonal distribution pattern of bacterioplankton indicated probable tight trophodynamical coupling both with phytoplankton and with heterotrophic flagellates, whereas heterotrophic flagellates showed a more trophic link with bacterial densities. Although approximately constant DOC and DON levels throughout the year sustained bacterial growth rates, during the phytoplankton growing season an increase of bacterial standing stocks was observed. Although the left-bank sampling site of the Elbe is strongly influenced by the tributaries Mulde and Saale containing higher concentrations of chloride, nitrogen nutrients, heavy metals and organic pollutants, no clear differences were observed between the two sides of the river concerning the biological parameters measured. Possible reasons and the slightly higher phytoplankton abundance and diversity at the right bank are discussed.     

Blood metal levels and metal-influenced immune functions of harbour seals in captivity

Immunological blood parameters and the effects of environmental pollutants on the immune system are important to assess the health status of seals. Animals living permanently in seal centres are useful for development and validation of diagnostic tools for free-ranging animals. In this study, parameters of cellular immunity as well as metal concentrations in blood and metal influence on cell proliferation of seven seals from a seal centre were investigated repeatedly using multi-element analysis and a lymphocyte proliferation assay. The metal concentrations, except for tin and chromium, were in general comparable to those of free-ranging animals of the North Sea. The unstimulated and mitogen-stimulated lymphocyte proliferation showed strong intra- and inter-individual variability, which reflected variability in activation of the immune status. Furthermore, both immunosuppressive and stimulative influences of metals on lymphocytes were found. Summarising, the methods used in this investigation provided useful information on these animals, and their application to free-ranging animals can be recommended.     

Metals and organochlorines in dolphins and porpoises of Cardigan Bay,West Wales

Concentrations of seven metals (Cr, Ni, Cu, Zn, Cd, Hg, and Pb) and a range of organochlorine pesticides, individual chlorobiphenyl congeners, and total polychlorinated biphenyls (PCB) have been determined in tissues of dolphins, porpoises, seals, and a variety of food chain species and sediments from Cardigan Bay, West Wales. Elevated concentrations of metals were not seen in any of the animal tissues examined. Higher than expected levels of organochlorine compounds were found in tissues of dolphins and porpoises; these concentrations are not derived from local pollution, but come from the animals' normal diet which did not show markedly elevated levels of organochlorines. The level of organochlorine bioaccumulation seen in some of the cetaceans analysed is much higher than found previously; this may have serious health implications for populations of those species around the coasts of NW Europe.     

Nematode response to metal, PAHs and organic enrichment in tourist marinas of the mediterranean sea

The structure of nematode assemblages was investigated in the sediments of two different tourist marinas in the Mediterranean Sea and related to pollution variables. Nematode densities and generic compositions were determined, as were concentrations of heavy metals, PAHs and organic matter. Results showed different assemblages at the two marinas, with a dominance of the genera Paralongicyatholaimus and Daptonema. Significant correlations between nematodes and concentrations of environmental contaminants were found. In particular, Paralongicyatholaimus showed a significant negative correlation with Cu concentrations and was almost absent at the stations where higher Cu concentrations were found. The presence of sensitive/tolerant nematode genera represents a promising tool to identify areas subjected to a higher level of disturbance and to define the correct environmental management strategy for harbors.     

Comparison of metal accumulation in the azooxanthellate scleractinian coral (Tubastraea coccinea) from different polluted environments

The response of metal accumulation in coral Tubastraea coccinea to various degrees of metal enrichment was investigated from the Yin-Yang Sea (YYS) receiving abandoned mining effluents, the Kueishan Islet (KI) hydrothermal vent field, and the nearshore area of remoted Green Island (GI). The concentrations of most dissolved metals were highest in seawater at YYS, followed by KI, and then GI, showing the effects of anthropogenic and venting inputs on metal levels. Five metals (Co, Fe, Mn, Ni, and Zn) yielded significant differences (p < 0.05) among the skeleton samples. We identified similar patterns in the metal–Ca ratios, indicating that the elevated metals in skeletons was a consequence of external inputs. The coral tissues were relatively sensitive in monitoring metal accumulation, showing significant differences among three locations for Cd, Co, Cu, Fe, Pb, Ni, and Zn. Specific bioconcentration factors provided strong support for the differential metal accumulation in skeletons and tissues.     

Trends und Verteilungsmuster in der Schadstoffbelastung von Sedimenten aus östlichen Bundeswasserstraßen

Trends and Patterns in the Contamination of Sediments from Federal Waterways in Eastern Germany The following study presents a concept for a sediment pollution cadastre and the results of systematic investigations of sediment contamination for eight toxic heavy metals and arsenic, as well as for eight classes of organic priority pollutants in all together 21 reaches in the Elbe and Oder waterway systems. Based on data from the years 1991 to 1995; multivariate statistical evaluations were carried out to identify local and temporal trends in the overall contamination. It was possible to differentiate between more non-point and point sources of sediment contamination. Because of the closure of substantial parts of the industry in Eastern Germany and by common sanitation efforts of both the German and the Czech sides since 1990, the situation in the Elbe river system with respect to the heavy metals has improved markedly. For the Oder river system, a comparable trend does not exist yet, and the sediment contamination by heavy metals is stagnant there. As a consequence, the pollution situation in both German parts of the rivers has become similar except for mercury and arsenic. Regarding organic pollutants, the picture is quite different. With the exception of PAHs, Oder sediments are contaminated by organics only to a lower extent and compare better with the ones from unpolluted waters found in parts of Brandenburg and Mecklenburg-Western Pomerania than with those of rivers Elbe, Mulde, and Saale with its tributaries. On the one hand, organic pollution generally also decreased since 1991 in these rivers. On the other hand, due to continuing inputs from plants in the Czech Republic and from old contaminated sites, both in Czechia and Germany, a decreasing trend is not significant or cannot be found at all for such pollutants as HCB, PCBs, or PAHs. The general trends are discussed in detail, e.g., by comparison with quality targets for sediments and suspended matter, and illustrated at the example of individual contaminants being typical for the overall situation.     

Increasing levels and biomagnification of persistent organic pollutants (POPs) in Antarctic biota

Representatives of the Antarctic food web (krill, cephalopod, fish, penguin, seal) of the area around Elephant Island and from the Weddell Sea were analysed for the most recalcitrant organochlorine compounds. Due to sorption of the compounds to sinking particles and accumulation in sediments, two benthic fish species (Gobionotothen gibberifrons, Chaenocephalus aceratus) feeding on benthos invertebrates and fish reflected significantly increasing concentrations within a decade (1987-1996), while a benthopelagic species (Champsocephalus gunnari) feeding on krill did not. In the pelagic food chain, lipid normalised concentrations of all compounds increased from Antarctic krill to fish proving that biomagnification of highly lipophilic pollutants (log octanol-water partition coefficient>5) occurs in water-breathing animals. As top predators Weddell and southern elephant seals (Leptonychotes weddellii, Mirounga leonina) biomagnified the persistent organic pollutants relative to krill 30-160 fold with the exception of hexachlorobenzene, the levels of which were lower than in fish indicating its intense specific elimination.     

DDT in endangered Galapagos sea lions (Zalophus wollebaeki)

We characterize for the first time the presence of DDT and its metabolites in tropical Galapagos sea lions (Zalophus wolleabeki). ∑DDT concentrations in Galapagos sea lion pups sampled in 2005 and 2008 ranged from 16 to 3070 μg/kg lipid. Concentrations of ∑DDT in pups in 2008 averaged 525 μg/kg lipid and were 1.9 times higher than that (281 μg/kg lipid) detected in pups in 2005. These concentrations are lower than those reported in many pinnipeds elsewhere, comparable to those in Hawaiian monk seals, and higher than those in southern elephant seals. The health risk characterization showed that 1% of the male pups exceeded the p,p′-DDE toxic effect concentration associated with anti-androgenic effects reported in rats. The findings provide preliminary guidance on the relationship between DDT use and ecological impacts, serving as a reference point against which possible future impact of tropical DDT use can be assessed.     

Assessment of Water Quality in the Elbe River at Flood Water Conditions Based on Cluster Analysis,Principle Components Analysis,and Source Apportionment

An assessment of water quality measurements during a spring flood in the Elbe River is presented. Daily samples were taken at a site in the middle Elbe, which is part of the network of the International Commission for the Protection of the Elbe River (IKSE/MKOL). Cluster analysis (CA), principal components analysis (PCA), and source apportionment (APCS apportioning) were used to assess the flood‐dependent matter transport. As a result, three main components could be extracted as important to the matter transport in the Elbe River basin during flood events: (i) re‐suspended contaminated sediments, which led to temporarily increased concentrations of suspended matter and of most of the investigated heavy metals; (ii) water discharge related concentrations of pedogenic dissolved organic matter (DOM) as well as preliminary diluted concentrations of uranium and chloride, parameters with stable pollution background in the river basin; and (iii) abandoned mines, i.e., their dewatering systems, with particular influence on nickel, manganese, and zinc concentrations.     

P/Ca in coral skeleton as a geochemical proxy for seawater phosphorus variation in Daya Bay, northern South China Sea

The P/Ca ratio in coral skeletons is considered to be a direct proxy for the nutrient P in seawater. We examined the reliability of this proxy by analyzing P/Ca in a Porites coral collected from a eutrophic area in the northern South China Sea. P concentrations were significantly higher compared to previously reported values from pristine and open seas, corresponding to the elevated nutrients from the study site. We compared coral P/Ca against recent in-situ records of seawater P concentrations. Our results show that P/Ca was primarily a function of TP sw rather than PO₄sw, and that the signal of skeletal P included not only phosphate, but also organic phosphorus. Besides the form of skeletal P, sub-sampling and analytical procedures and the distinctive nutrient regime were the most reasonable explanations for our results. We suggest that total P in coral skeletons may be an efficient proxy for seawater P variations and associated phytoplankton dynamics in eutrophic environments.     

Heavy metals in Chukchi Sea sediments as compared to selected circum-arctic shelves

Surficial sediments from 31 stations on the northeastern Chukchi Sea, Alaskan Arctic were analysed by AAS and ICP-AES for Si, Al, Fe, Mn, Cu, Cr, Co, Zn, Ni and V. The metal concentrations are related to the sediment granulometry and show no correlations with organic carbon. Presumably all the heavy metals, except Cr and Co, are either adsorbed on clays and/or coprecipitated with ferrimanganic hydroxide. Cobalt is partitioned in an unknown mineral phase within the sand fraction.

Comparison of the heavy metal concentrations in muds of the Chukchi Sea with those of the high arctic shelves of Russia, East Greenland and the Beaufort Sea shows relatively lower levels of most metals in the Chukchi. Presumably these disparities are related to regional differences in sediment chemistries inherited from natural terrigenous sources rather than to any enhanced pollution in the non-Chukchi areas.

It is suggested that the concentrations and accumulation rates of the heavy metals reported here can serve as reliable baselines to monitor metal pollution in the Chukchi Sea.     

Biomonitoring of organochlorine compounds and trace metals along the Eastern Adriatic coast (Croatia) using Mytilus galloprovincialis

The paper presents the results of monitoring trace organic contaminants (17 PCBs and 7 OCPs) and 6 trace metals (Cd, Cr, Cu, Hg, Pb and Zn) in the coastal waters of the eastern Adriatic in 2006 using Mytilus galloprovincialis as indicator species. OCPs were found in all samples (0.07-14.3 ng g⁻¹ d.wt.), while in positive samples concentrations of PCBs ranged between 0.16 and 20.5 ng g⁻¹ d.wt. The α-HCH/γ-HCH and DDE/DDT ratios indicated recent input of γ-HCH and DDT. Spatial distributions of HCB, PCBs, DDTs and Hg were significantly correlated with population density. Although elevated concentrations of all trace metals and organic contaminants were recorded in the densely populated and industrialized areas, overall data point to relatively low level of contamination of the eastern Adriatic coast. Evaluation of the risks to human health associated with consumption of the mussels suggested that there is no health risk for moderate shellfish consumers.     

Petrowatch: Petroleum hydrocarbons,synthetic organic compounds,and heavy metals in mussels from the Monterey Bay area of central California

Mussel Watch techniques were used to measure the concentrations of petroleum hydrocarbons, synthetic organic hydrocarbons, and trace metals in a preliminary study of the Monterey Bay area in central California. Resident mussels were found to have higher-than-expected petroleum hydrocarbon body burdens in Carmel Bay, an area thought to be relatively contaminant free. A ‘hot spot’ of PCB 1254 and pp′DDE was measured at Año Nueuvo Island, a site previously recognized because of elevated levels of mercury in mussels. PCB 1254 concentrations at Año Nuevo Island were high in relation to the remainder of coastal United States and Baja California, reflecting entrainment of this compound at a biologically active area. The Monterey Harbor Jetty location showed the highest contamination levels for zinc and lead. In fact, this location has the second highest lead concentrations in mussels for the California coast. Biological cycling of certain compounds (PCB, DDT and mercury) in remote locations such as Año Nuevo Island, is hypothesized as a mechanism for these elevated concentrations in mussels. Levels of other synthetic organic hydrocarbons were generally low, with chlordanes showing higher concentrations in the more urbanized locations of the study area, i.e. the Monterey Harbor Jetty.