Cytokine expression and lymphocyte proliferative capacity in diseased harbor porpoises (Phocoena phocoena) - Biomarkers for health assessment in wildlife cetaceans.

Harbor porpoises (Phocoena phocoena) in the North and Baltic Seas are exposed to anthropogenic influences including acoustic stress and environmental contaminants. In order to evaluate immune responses in healthy and diseased harbor porpoise cells, cytokine expression analyses and lymphocyte proliferation assays, together with toxicological analyses were performed in stranded and bycaught animals as well as in animals kept in permanent human care. Severely diseased harbor porpoises showed a reduced proliferative capacity of peripheral blood lymphocytes together with diminished transcription of transforming growth factor-ß and tumor necrosis factor-α compared to healthy controls. Toxicological analyses revealed accumulation of polychlorinated biphenyls (PCBs), dichlorodiphenyldichloroethylene (DDE), and dichlorodiphenyltrichloroethane (DDT) in harbor porpoise blood samples. Correlation analyses between blood organochlorine levels and immune parameters revealed no direct effects of xenobiotics upon lymphocyte proliferation or cytokine transcription, respectively. Results reveal an impaired function of peripheral blood leukocytes in severely diseased harbor porpoises, indicating immune exhaustion and increased disease susceptibility.

Analysis of estrogenic activity in coastal surface waters of the Baltic Sea using the yeast estrogen screen.

In the present study, the yeast estrogen screen (YES) has been used to assess the estrogenic activity in surface waters of a coastal region in the German Baltic Sea. Solid-phase extraction using the copolymer Oasis HLB followed by a clean-up on silica was carried out on approximately 50-l water samples. From the final 400 microl extract volume, 100 microl aliquots were used for the measurement of estrogenic activity and for chemical analysis, which was performed by liquid chromatography coupled to tandem mass spectrometry (LC-MS/MS). From 29 samples taken during two campaigns (2003 and 2004) at five different stations 27 samples showed an estrogenic response higher than 10%. The response in the YES was expressed as measured estradiol equivalents (EEQs), which were in the range of 0.01 (Darss Peninsula) to 0.82 ng/l (Inner Wismar Bay). Samples from stations located in inner coastal waters showed higher estrogenic activities than those from outer located stations. A comparison of measured estrogenicity (YES) and calculated estrogenicity (chemical analysis) showed significant differences, probably due to the presence of anti-estrogenic compounds and/or the estrogenic activity of unknown, not identified contaminants. The main contributors to the overall estrogenic activity were synthetic and natural hormones.

Liquid chromatography-tandem mass spectrometry analysis of estrogenic compounds in coastal surface water of the Baltic Sea.

An analytical method has been developed for the determination of five naturally occurring estrogens (estradiol, estriol, estrone, genistein, daidzein), one synthetic hormone (ethynylestradiol) and three xenoestrogens (4-nonylphenol (NP), 4-tert-octylphenol (4-tert-OP), bisphenol A (BPA)) in coastal marine waters. The procedure includes a solid-phase extraction of approx. fifty litres of water samples on the solid-phase copolymer Oasis HLB followed by a clean-up on silica. Twenty-five percent aliquots were used for the analytical determination of the analytes using high performance liquid chromatography coupled with electrospray-ionisation tandem mass spectrometry (HPLC-ESI-MS/MS). Calculated extraction recoveries between 52 (4-tert-octylphenol) and 91% (nonylphenol) were obtained for the method developed. Matrix interferences occurring during electrospray ionisation were quantified by spiking the extracts prior to the measurements. Method detection limits ranged from 0.02 (estrone) to 1 ng L(-1) (estriol). The method was applied to determine environmental estrogens in coastal waters of the Baltic Sea. The analyses showed the presence of five compounds at levels between 0.10 (estrone) and 17 ng L(-1) (ethynylestradiol).

Investigations of the potential influence of environmental contaminants on the thymus and spleen of harbor porpoises (Phocoena phocoena).

Harbor porpoises from the German North and Baltic Seas exhibit a higher incidence of bacterial infections compared to whales from less polluted arctic waters. The potential adverse effect of environmental contaminants such as polychlorinated biphenyls (PCBs) and heavy metals on the immune system and the health status of marine mammals is still discussed controversially. The aim of the present study was to investigate the possible influence of PCB, polybrominated diphenyl ether (PBDE), toxaphene, (p,p'-dichlorodiphenyl)trichlorethane (DDT), and (p,p'-dichlorodiphenyl)dichlorethene (DDE) on the immune system of harbor porpoises. Lymphoid organs are influenced by a variety of factors, and therefore special emphasis was given to separating the confounding effect of age, health status, nutritional state, geographical location, and sex from the effect of contaminant levels upon thymus and spleen. Contaminant analysis and detailed pathological examinations were conducted on 61 by-caught and stranded whales from the North and Baltic Seas and Icelandic and Norwegian waters. Stranded harbor porpoises were more severely diseased than by-caught animals. Thymic atrophy and splenic depletion were significantly correlated to increased PCB and PBDE levels. However, lymphoid depletion was also associated with emaciation and an impaired health status. The present report supports the hypothesis of a contaminant-induced immunosuppression, possibly contributing to disease susceptibility in harbor porpoises. However, further studies are needed to determine if lymphoid depletion is primarily contaminant-induced or secondary to disease and emaciation in this cetacean species.

Potential contamination of shipboard air samples by diffusive emissions of PCBs and other organic pollutants: implications and solutions.

Air samples were taken onboard the RRS Bransfield on an Atlantic cruise from the United Kingdom to Halley, Antarctica, from October to December 1998, with the aim of establishing PCB oceanic background air concentrations and assessing their latitudinal distribution. Great care was taken to minimize pre- and post-collection contamination of the samples, which was validated through stringent QA/QC procedures. However, there is evidence that onboard contamination of the air samples occurred,following insidious, diffusive emissions on the ship. Other data (for PCBs and other persistent organic pollutants (POPs)) and examples of shipboard contamination are presented. The implications of these findings for past and future studies of global POPs distribution are discussed. Recommendations are made to help critically appraise and minimize the problems of insidious/diffusive shipboard contamination.

Seasonal variation of polychlorinated biphenyl concentrations in the southern part of the Baltic Sea.

The impact of seasonal fluctuations in forcing factors such as atmospheric concentration, temperature, and biological productivity on the concentration of polychlorinated biphenyls (PCBs) in the surface water of the southern part of the Baltic Sea was investigated. Water samples were collected on eight cruises over 2 years. A clear seasonal variability in dissolved PCB concentrations was observed with higher levels in summer than in winter and spring. This was attributed to changes in atmospheric concentrations and water temperature, based on measurements showing the PCB levels in the atmosphere and surface water to be close to a partitioning equilibrium. Concentrations in the suspended particulate material (SPM) fraction were also variable, and when the quotient of the organic carbon normalised concentration in SPM and the dissolved concentration was calculated (i.e., the bioaccumulation factor (BAF)), a seasonal pattern was observed which was consistent with kinetic limitations on partitioning into particles caused by plankton growth. However, seasonal variability in the partitioning properties of the SPM may also contribute to this variability.

The air-sea equilibrium and time trend of hexachlorocyclohexanes in the Atlantic Ocean between the Arctic and Antarctica.

Hexachlorocyclohexanes (HCHs) were determined simultaneously in air and seawater during two cruises across the Atlantic Ocean between the Arctic Ocean (Ny-Alesund/ Svalbard, 79 degrees N; 12 degrees E) and the Antarctic Continent (Neumayer Station/ Ekstroem Ice Shelf, 70 degrees S; 8.2 degrees W) in 1999/ 2000. The concentrations of alpha-HCH and gamma-HCH in air and surface waters of the Arctic exceeded those in Antarctica by 1-2 orders of magnitude. The gaseous concentrations of gamma-HCH were highest above the North Sea and between 20 degrees N and 30 degrees S. Fugacity fractions were used to estimate the direction of the air-sea gas exchange. These showed for alpha-HCH thatthe measured concentrations in both phases were close to equilibrium in the North Atlantic (78 degrees N-40 degrees N), slightly undersaturated between 30 degrees N and 10 degrees S and again close to equilibrium between 20 degrees S and 50 degrees S. Y-HCH has reached phase equilibrium in the North Atlantic as alpha-HCH, but the surface waters of the tropical and southern Atlantic were strongly undersaturated with y-HCH, especially between 30 degrees N and 20 degrees S. These findings are significantly different from two earlier estimates around 1990 as a result of global emission changes within the past decade. Therefore, we investigated the time trend of the HCHs in the surface waters of the Atlantic between 50 degrees N and 60 degrees S on the basis of archived samples taken in 1987-1997 and those from 1999. A decrease of alpha-HCH by a factor of approximately 4 is observed at all sampling locations. No decrease of gamma-HCH occurred between 30 degrees N and 30 degrees S, but there was a decrease in the North Atlantic, North Sea, and in the South Atlantic south of 40 degrees S. The constant level of gamma-HCH in the tropical Atlantic confirms the conclusion that the tropical Atlantic acts as a sink for y-HCH at present time. The measured alpha-HCH seawater concentrations were compared with results from a global multimedia fate and transport model. Whereas the time trend over 13 years and the latitudinal gradient were well reproduced by the model, the absolute levels were too high by a factor of 4.5. This may be explained by the zonal averaging employed in the model as well as uncertain emissions and degradation rates.