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Most exposure assessments for free-ranging cetaceans focus on contaminant concentrations measured in blubber, and few data are available for other tissues or the factors governing contaminant distribution among tissues. The goal of this study was to provide a detailed description of the distribution of persistent organic pollutants (POPs) within the common bottlenose dolphin (Tursiops truncatus) body and assess the role of lipid dynamics in mediating contaminant distribution. Thirteen tissues (brain, blubber, heart, liver, lung, kidney, mammary gland, melon, skeletal muscle, spleen, thyroid, thymus, and testis/uterus) were sampled during necropsy from bottlenose dolphins (n = 4) and analyzed for lipid and 85 POPs, including polychlorinated biphenyls, organochlorine pesticides, and polybrominated diphenyl ethers. Significant correlations between tissue POP concentrations and lipid suggest that distribution of POPs is generally related to tissue lipid content. However, blubber:tissue partition coefficients ranged widely from 0.753 to 6.25, suggesting that contaminant distribution is not entirely lipid-dependent. Tissue-specific and whole-body contaminant burdens confirmed that blubber, the primary site of metabolic lipid storage, is also the primary site for POP accumulation, contributing >90% to the whole-body burdens. Observations also suggest that as lipid mobilizes from blubber, contaminants may redistribute, leading to elevated tissue concentrations. These results suggest that individuals with reduced blubber lipid may be at increased risk for exposure-related health effects. However, this study also provides evidence that the melon, a metabolically inert lipid-rich structure, may serve as an alternate depot for POPs, thus preventing the bulk of blubber contaminants from being directly available to other tissues. This unique physiological adaptation should be taken into consideration when assessing contaminant-related health effects in wild cetacean populations. Environ. Toxicol. Chem. 2010;29:1263–1273. © 2010 SETAC [ABSTRACT FROM AUTHOR]

The measurement of steroid hormones (e.g., androgens, estrogens, progestins, and glucocorticoids) in alternative matrices (e.g., feces, urine, blubber, saliva, blow, milk, and ocular secretion) has been increasingly used in research with aquatic mammals. The aim of this review is to briefly summarize studies using steroid analysis in alternative matrices from captive and free-ranging aquatic mammal species. The analysis of steroid hormones from alternative matrices is a powerful tool to obtain information about reproductive biology and social behavior in free-ranging aquatic mammals, as well as to help in the management of captive animals. However, for a consistent monitoring of steroid hormones in alternative matrices, it is of crucial importance to verify if a chosen matrix and assay reliably reflects physiologic events. [ABSTRACT FROM AUTHOR]

Blubber samples of Indo-Pacific bottlenose (Tursiops aduncus) and spinner (Stenella longirostris) dolphins from Zanzibar, East Africa, were analyzed for a wide range of organohalogen compounds. Methoxylated polybrominated diphenyl ethers (MeO-BDEs), presumably biogenic, were found at higher concentrations than anthropogenic organochlorine pesticides (OCPs). Only traces of industrial pollutants, such as polychlorinated biphenyls, were detected. The OCP levels found off Zanzibar were lower than those reported from other regions while MeO-BDE levels were higher. The relative composition of the OCPs indicated recent use of lindane (γ-hexachlorocyclohexane) and aged residues of DDT and technical HCH. Placental transfer was estimated to 2.5% and 0.5% of the total burden of OCPs and MeO-BDEs, respectively. Overall transfer from mother to calf in Indo-Pacific bottlenose dolphins was estimated to 72% and 85% for the OCPs and MeO-BDEs burdens, respectively. Health effects of MeO-BDEs are not known, but structural similarities with well-known environmental toxins are cause for concern. [Copyright &y& Elsevier]

Blubber from stranded South American sea lions ( Otaria flavescens) was sampled between 1991 and 2005 on the Peninsula Valdés in Argentina and analyzed for organochlorine (OC) pollutants. Mean blubber concentrations, expressed on an extractable basis, were 686 (SD = 1,060) ng g−1 for dichlorodiphenyl trichloroethane (tDDT) and 735 (SD = 787) ng g−1 for polychlorinated byphenils (PCB). The OC levels were well below those associated with adverse sublethal effects and lethality in mammals. OC concentrations showed statistically significant associations with age that were positive in males and negative in females. These trends are consistent with the majority of marine mammal populations studied. There were no trends in the levels of tDDT or PCB over time. In spite of the low levels detected, OC contamination was present consistently over the 14-year period, suggesting continuous inputs from geographic redistribution. [ABSTRACT FROM AUTHOR]

Blubber biopsies were collected from 18 adult male walruses from Svalbard, Norway. The biopsies were taken vertically through the skin and the entire blubber layer down to, but not including, the muscle layer. Fatty acid (FA) compositions of inner blubber, outer blubber and dermis of the walruses and of potential prey organisms were determined. The three layers differed significantly from one another in FA composition. Generally, the inner blubber contained more long-chained monounsaturated, saturated and polyunsaturated FAs, while the outer blubber and dermis contained more short-chained monounsaturated FAs. This stratification is similar to what has been observed in other marine mammal species. However, differences between layers were less pronounced than in most other species, possibly because the extremely thick overlying dermis of walruses provides an insulating shield, which affects the FA composition of the outer blubber. The FA composition of the potential prey organisms was different from that of the blubber of the walruses, although more similar to the inner blubber than to the outer blubber or dermis. FA composition in the inner blubber was not significantly correlated with age (assessed by tusk volume), while the FA composition of the outer blubber and dermis were significantly correlated with age. [ABSTRACT FROM AUTHOR]

Blubber samples from 33 Guiana dolphins (Sotalia guianensis) from three estuaries (Guanabara, Sepetiba/Ilha Grande and Paranaguá Bays) of Southern and Southeastern Brazil were analyzed for organochlorine compounds (DDTs, PCBs and HCB). The sampled individuals were incidentally captured in gillnet fishery between 1995 and 2005. The concentrations (in ng/g lipids) varied from 652 to 23 555 for ΣDDT; from 765 to 99 175 for ΣPCB; and from <4.4 to 156 for HCB. The results have shown that cetaceans from Brazil present organochlorine concentrations that are comparable to those reported for highly industrialized regions of Northern Hemisphere. Using discriminant analysis it was possible to verify that the dolphin populations from the three bays present different organochlorine accumulation patterns. This feature allows the use of this set of pollutants as an auxiliary tool for identification of different populations of the species off Brazilian Coast. [Copyright &y& Elsevier]

A previous study has shown a simultaneous increase of vitamin A and PCBs in grey seal (Halichoerus grypus) milk at late lactation (). Here we sought to understand this unexpected relationship by comparing the dynamics of vitamin A and PCBs in the different tissue compartments of transfer. Lactating grey seals and their pups were sampled longitudinally in Scotland during the 2006 breeding season. As blubber reserves decreased, concentrations of vitamin A and PCBs increased during lactation in the inner layer of maternal blubber. A concomitant rise was observed in milk and consequently in the serum of suckling pups. The similar dynamics of vitamin A and PCBs in milk and inner blubber suggest a common mechanism of mobilisation from maternal body stores and transfer into the milk. A panel data analysis highlighted a negative impact of PCBs in milk and pup serum on vitamin A status in pup serum. [Copyright &y& Elsevier]

Abstract: Polychlorinated biphenyls (PCBs), chlorinated pesticides (i.e., dichlorodiphenyltrichloroethane (DDT) and its metabolites, chlordanes (CHLs), dieldrin, hexachlorobenzene (HCB), and mirex), polybrominated diphenyl ethers (PBDEs), perfluorinated chemicals (PFCs), and polyaromatic hydrocarbons (PAHs) were measured in blubber biopsy samples collected from 139 wild bottlenose dolphins (Tursiops truncatus) during 2003–2005 in Charleston (CHS), SC and the Indian River Lagoon (IRL), FL. Dolphins accumulated a similar suite of contaminants with ∑PCB dominating (CHS 64%, IRL 72%), followed by ∑DDT (CHS 20%, IRL 17%), ∑CHLs (CHS 7%; IRL 7%), ∑PBDE (CHS 4%, IRL 2%), PAH at 2%, and dieldrin, PFCs and mirex each 1% or less. Together ∑PCB and ∑DDT concentrations contributed ∼87% of the total POCs measured in blubber of adult males. ∑PCBs in adult male dolphins exceed the established PCB threshold of 17mg/kg by a 5-fold order of magnitude with a 15-fold increase for many animals; 88% of the dolphins exceed this threshold. For male dolphins, CHS (93,980ng/g lipid) had a higher ∑PCBs geomean compared to the IRL (79,752ng/g lipid) although not statistically different. In adult males, the PBDE geometric mean concentration was significantly higher in CHS (5920ng/g lipid) than the IRL (1487ng/g). Blubber ∑PFCs concentrations were significantly higher in CHS dolphins. In addition to differences in concentration of PCB congeners, ∑PBDE, TEQ, ∑CHLs, mirex, dieldrin, and the ratios ∑DDE/∑DDT and trans-nonachlor/cis-nonachlor were the most informative for discriminating contaminant loads in these two dolphin populations. Collectively, the current ∑PCB, ∑DDT, and ∑PBDEs blubber concentrations found in CHS dolphins are among the highest reported values in marine mammals. Both dolphin populations, particularly those in CHS, carry a suite of organic chemicals at or above the level where adverse effects have been reported in wildlife, humans, and laboratory animals warranting further examination of the potential adverse effects of these exposures. [Copyright &y& Elsevier]

Abstract: Selected POPs were analyzed in blubber samples of Pontoporia blainvillei from Southern Brazil to appraise temporal trend over a 10 year period (1994–2004). Overall, levels of POPs were relatively low, especially when compared to Northern Hemisphere concentrations. Apart from Mirex and PCBs, which showed stable concentrations, DDTs, HCB, CHLs, Dieldrin levels presented a slight decrease over the studied period. In addition, the increase in the PCBs/DDTs ratio supports the idea that inputs of DDTs are decaying faster than PCBs. [Copyright &y& Elsevier]

Abstract: Harbour porpoises sampled within the UK Cetacean Strandings Investigation Programme have been analysed for 25 chlorobiphenyl congeners. In all, 440 porpoises stranded or bycaught during the period 1991–2005 were studied. There are regional differences in the trend in summed congener concentrations over time but, despite controls on PCBs having been in place for decades, they are declining only slowly. Their toxic impacts in UK porpoises – increased susceptibility to infectious disease mortality in the most contaminated individuals – looks likely to continue for some time yet. Further efforts to limit or eliminate PCB discharges to the marine environment are still needed. [Copyright &y& Elsevier]

Abstract: Enantioselective analyses of the chiral brominated flame retardant 2,3-dibromopropyl-2,4,6-tribromophenyl ether (DPTE) are the focus of this work. High performance liquid chromatography (HPLC) equipped with a column that had a chiral stationary phase consisting of a modified cellulose derivative allowed for the fractionation of the enantiomers of DPTE. The enantiomeric excess was 98.2% for enantiomer 1 and 99% for enantiomer 2. Polarimetric measurements verified that the first eluting enantiomer originated from (−)-DPTE and the second peak originated from (+)-DPTE. Two gas chromatographic columns allowed for the direct enantioresolution of DPTE. The elution order of DPTE enantiomers was the same as observed in the chiral HPLC system ((−)-DPTE before (+)-DPTE). The best enantioseparation was achieved on a Chirasil-DEX CB column, which was used to analyze the enantiomer fractions of DPTE in blubber and brain samples of hooded seals (Cystophora cristata) and harp seals (Phoca groenlandica) from the Barents and Greenland Seas. Analyses were carried out by means of gas chromatography/electron capture negative ion mass spectrometry operated in the selected ion monitoring (GC/ECNI-MS–SIM) mode. In both matrices, only minute deviations from the racemate were observed (maximum ±3% excess of (−)-DPTE). However, the samples from the Barents Sea were either racemic or showed a slight excess of (+)-DPTE (up to 2.5%), whereas all samples from the Greenland Sea contained a slight excess (up to 4%) of (−)-DPTE. [Copyright &y& Elsevier]

Abstract: We report on the comparative bioaccumulation, biotransformation and/or biomagnification from East Greenland ringed seal (Pusa hispida) blubber to polar bear (Ursus maritimus) tissues (adipose, liver and brain) of various classes and congeners of persistent chlorinated and brominated contaminants and metabolic by-products: polychlorinated biphenyls (PCBs), chlordanes (CHLs), hydroxyl (OH-) and methylsulfonyl (MeSO2-) PCBs, polybrominated biphenyls (PBBs), OH-PBBs, polybrominated diphenyl ether (PBDE) and hexabromocyclododecane (HBCD) flame retardants and OH- and methoxyl (MeO-) PBDEs, 2,2-dichloro-bis(4-chlorophenyl)ethene (p,p′-DDE), 3-MeSO2-p,p′-DDE, pentachlorophenol (PCP) and 4-OH-heptachlorostyrene (4-OH-HpCS). We detected all of the investigated contaminants in ringed seal blubber with high frequency, the main diet of East Greenland bears, with the exception of OH-PCBs and 4-OH-HpCS, which indicated that these phenolic contaminants were likely of metabolic origin and formed in the bears from accumulated PCBs and octachlorostyrene (OCS), respectively, rather than being bioaccumulated from a seal blubber diet. For all of the detectable sum of classes or individual organohalogens, in general, the ringed seal to polar bear mean BMFs for ΣPCBs, p,p′-DDE, ΣCHLs, ΣMeSO2-PCBs, 3-MeSO2-p,p′-DDE, PCP, ΣPBDEs, total-(α)-HBCD, ΣOH-PBDEs, ΣMeO-PBDEs and ΣOH-PBBs indicated that these organohalogens bioaccumulate, and in some cases there was tissue-specific biomagnification, e.g., BMFs for bear adipose and liver ranged from 2 to 570. The blood-brain barrier appeared to be effective in minimizing brain accumulation as BMFs were ≤1 in the brain, with the exception of ΣOH-PBBs (mean BMF=93±54). Unlike OH-PCB metabolites, OH-PBDEs in the bear tissues appeared to be mainly accumulated from the seal blubber rather than being metabolic formed from PBDEs in the bears. In vitro PBDE depletion assays using polar bear hepatic microsomes, wherein the rate of oxidative metabolism of PBDE congeners was very slow, supported the probability that accumulation from seals is the main source of OH-PBDEs in the bear tissues. Our findings demonstrated from ringed seal to polar bears that organohalogen biotransformation, bioaccumulation and/or biomagnification varied widely and depended on the contaminant in question. Our results show the increasing complexity of bioaccumulated and in some cases biomagnified, chlorinated and brominated contaminants and/or metabolites from the diet may be a contributing stress factor in the health of East Greenland polar bears. [Copyright &y& Elsevier]

The article presents a study which aims to describe a possible method for age determination of ageing live free-ranging humpback whales Megaptera novaeangliae using blubber fatty acid compositions of biopsy samples. Shallow outer-blubber were derived from known-age whales from 2 distinct populations and examined for their fatty acid (FA) compositions. Four FA-age models were developed, including one for each humpback population examined separately, and an additional 2 by mixing both populations into a single dataset and deriving models based on exact and exact plus minimum known-age whales independently. The results indicate that it may be possible to firgure the age of individual humpback whales from any population using the approach, which could be better than decadal approach.

Abstract: Persistent organic pollutants (POPs), including polychlorinated biphenyls (PCBs), polychlorinated dibenzo-p-dioxins (PCDDs), and dibenzofurans (PCDFs), are ubiquitous environmental contaminants of which significant concentrations are reported in upper trophic level animals. In 1998, we collected blubber biopsy samples (n =11) from killer whales (Orcinus orca) inhabiting the coastal waters around Possession Island, Crozet Archipelago, southern Indian Ocean, for contaminant analyses. Despite inhabiting an isolated region far removed from industrial activities, these killer whales can presently be considered among the most PCB-contaminated cetaceans in the southern hemisphere, with concentrations ranging from 4.4 to 20.5mg/kg lipid weight (lw). PCDD levels ranged from below the detection limit (5ng/kg) to 77.1ng/kglw and PCDF levels from below the detection limit (7ng/kg) to 36.1ng/kglw. Over 70% of our study animals had PCB concentrations which exceeded a 1.3mg/kg PCB threshold established for endocrine disruption and immunotoxicity in free-ranging harbour seals, suggesting that organic contaminants cannot be ruled out as an additional threat to this declining population. [Copyright &y& Elsevier]

Concentrations of hexabromocyclododecanes (HBCDs), polybrominated diphenyl ethers (PBDEs), and three novel flame retardants, namely 2-ethylhexyl 2,3,4,5-tetrabromobenzoate (TBB), bis-(2-ethylhexyl)-tetrabromophthalate (TBPH), and hexachlorocyclopentadienyldibromocyclooctane (HCDBCO), were determined in blubber samples of Indo-Pacific humpback dolphins (Sousa chinensis) and finless porpoises (Neophocaena phocaenoides). The levels of HBCDs and PBDEs in cetacean samples ranged from 4.1 to 519 and 103 to 51,100 ng/g lw, respectively. A significant increasing trend of ΣHBCDs was observed in dolphin samples from 1997 to 2007 with an estimated annual rate of 5%, whereas no significant temporal trends of ΣPBDEs appeared over the sampling period. This pattern may be attributed to the increasing usage of HBCDs following the restriction/voluntary withdrawal of the production and use of PBDE commercial mixtures in several countries. HCDBCO was not found in the blubber samples. This is the first report of the presence of TBB and TBPH, two new flame retardants that have previously been identified in house dust from the U.S., in marine mammals; concentrations of these compounds in dolphins and porpoises ranged from the instrumental detection limit (IDL) (<0.04) to 70 and IDL (<0.04) to 3859 ng/g lw, respectively. Levels of TBPH were comparable to ΣHBCDs in porpoise samples. The presence of these novel flame retardants in top-trophic-level marine organisms raises concern about their release into the environment and indicates the need for further monitoring of these compounds in other environmental matrices. [ABSTRACT FROM AUTHOR]

Adult leatherback turtles are gigantothermic/endothermic when foraging in cool temperate waters, maintaining a core body temperature within the main body cavity of ca. 25°C despite encountering surface temperatures of ca. 15°C and temperatures as low as 0.4°C during dives. Leatherbacks also eat very large quantities of cold, gelatinous prey (medusae and pyrosomas). We hypothesised that the head and neck of the leatherback would have structural features to minimise cephalic heat loss and limit cooling of the head and neck during food ingestion. By gross dissection and analytical computed tomography (validated by ground truthing dissection) of an embalmed specimen we confirmed this prediction. 21% of the head and neck was occupied by adipose tissue. This occurred as intracranial blubber, encapsulating the salt glands, medial portions of the eyeballs, plus the neurocranium and brain. The dorsal and lateral surfaces of the neck featured thick blubber pads whereas the carotid arteries and jugular veins were deeply buried in the neck and protected laterally by blubber. The oesophagus was surrounded by a thick sheath of adipose tissue whereas the oropharyngeal cavity had an adipose layer between it and the bony proportion of the palate, providing further ventral insulation for salt glands and neurocranium. [ABSTRACT FROM AUTHOR]

Many studies have demonstrated that persistent organic pollutants are transferred from mother to pup during lactation in phocid seals, but none have been able to determine the significance of these findings for survivorship. The aim of this study was to investigate the relationship between blubber contaminant concentrations and first-year survival in gray seal pups. A mark-recaputre framework was used to estimate survival probabilities and animals were "marked" using novel mobile phone tugs. Individual and group covariates (sex, condition, and blubber contaminants) were embedded within a live-resighting model. The most significant covariates remained condition at weaning and sex (males in poor condition had the lowest survival probability), as was found previously, but there was also evidence indicating that higher blubber contaminants additionally decreased survivorship. The models' Akaike's Information Criteria (AICs) and their associated weights, point toward the tetrapolybrominated diphenyl ether congeners (dominated by BDE-47) as being the most important group of contaminants effecting survival probability, followed by the total dichlorodiphenyltrichloroethanes (DDTs) and pentapolychlorinated biphanyl congeners. Those compounds were not the most abundant in the blubber, suggesting further studies into their toxicological effects in this species are necessary. The specific mechanisms driving the reduction in survivorship remain unknown. [ABSTRACT FROM AUTHOR]

A novel molecular technique was used to measure blubber testosterone (BT) in 114 male short-beaked common dolphins, Delphinus delphis, collected from incidental fishery bycatch and strandings. When these concentrations were compared across maturity states, the mean (± SEM) BT levels of mature D. delphis (14.3 ± 3.0 ng/g) were significantly higher than those of pubertal (2.5 ± 0.5 ng/g, P= 0.006) and immature animals (2.2 ± 0.3 ng/g, P < 0.0001). BT concentrations in mature males were significantly higher in summer months (53.9 ± 2.0 ng/g) than during the rest of the year (7.9 ± 0.69 ng/g, P < 0.0001), indicating reproductive seasonality. An analysis of BT in different anatomical locations showed that hormone concentrations were not homogenous throughout the body; the levels in the dorsal fin were significantly lower than in most other areas ( F= 5.39, P= 0.043). Conversely, we found no significant differences in BT concentration with respect to subepidermal depth ( F= 2.09, P= 0.146). Finally, testosterone levels in biopsies from 138 free-swimming male D. delphis, of unknown maturity state, sampled off California were found to be of concentrations similar to those from the fishery bycatch and stranding samples and revealed an analogous trend with respect to ordinal date. [ABSTRACT FROM AUTHOR]

Blubber is a critical component of thermoregulation for marine mammals, particularly for cetaceans. However, the cost of overcoming blubber's buoyant force during descent could constrain blubber deposition. One- to 12-year-old healthy, free-ranging common bottlenose dolphins (Tursiops truncatus) were studied in Sarasota Bay, Florida, during summer (mean water temperature: 29.7°C ± 0.1 SE) and winter (mean water temperature: 19.2 ± 0.4°C) to examine ontogenetic and seasonal trends in morphology and blubber deposition. Surface-area-to-volume ratio decreased significantly with age. During summer, yearlings had significantly thicker blubber than 2- to 12-year-old animals but this difference diminished by winter because blubber deposition in response to the colder water temperature was smaller in yearlings (2-mm increase) compared to 2- to 12-year-old animals (3- to 6-mm increase). During summer, buoyancy was highest in yearlings (6.24 N ± 0.41 SE), compared to a buoyant force of -0.98 ± 0.90 N (neutrally buoyant) for 12-year-old animals. Conversely, all dolphins converged upon a similar buoyant force (8.01 ± 0.56 N) in winter. The elevated buoyancy of yearlings in summer presumably limits seasonal blubber adjustments, because all yearlings (regardless of season) converged upon a similar calculated mass-specific cost of descent that was greater than all other age classes. Balancing energetic demands of thermoregulation and locomotion may limit the flexibility of yearlings to adjust blubber deposition in response to fluctuating water temperatures. [ABSTRACT FROM AUTHOR]

The article presents a study which examined diet-based resource partitioning among seals by analyzing the blubber fatty acids (FAs) of adult and juvenile southern elephant seals. The researchers investigated FAs from blubber of 122 juvenile seals and compared them to FA profiles of 52 adult seal females, and from 51 prey species including fish and squid. The FA signature analysis showed differences in the physiological and dietary aspects between ages. The study suggested that female seals were consuming different prey, and that the differences in diet between ages propose that resource partitioning happens in response to large physiological and metabolic differences with ages.

Blubber samples were analyzed for anthropogenic and natural persistent organohalogens in nine killer whales (Orcinus orca) stranded on the northern coast of Japan in 2005. Anthropogenic organohalogens were dominated by DDTs (40–240 µg/g lipid weight (lw)), PCBs (19–68 µg/g lw), and chlordanes (trans-nonachlor, 15–80 µg/g lw). Polybrominated diphenyl ethers (PBDEs) were detected at a range of 0.22–0.64 µg/g lw (BDE-47, 42–74% of ΣPBDE). For natural organohalogens, mixed halogenated dimethylbipyrroles (Br4Cl2-DBP, 6.4–26 µg/g lw), heptachlorinated methylbipyrrole (Cl7-MBP, 0.5–1.9 µg/g lw), two methoxylated tetrabromodiphenyl ethers (6-MeO-BDE47, 0.11–0.58 µg/g lw; 2''-MeO-BDE68, 0.02–0.06 µg/g lw), and dimethoxylated tetrabromobiphenyl (2,2''-diMeO-BB80, 0.06–0.20 µg/g lw) were present. These concentrations in the blubber were higher in calves than in lactating females, indicating that large quantities of the persistent organohalogens transferred from the mother to the calf through lactation. The mother-to-calf transfer ratios of PCBs and PBDEs were significantly decreased with increasing number of halogen substituents, suggesting that higher halogenated congeners are less transferable. [Copyright &y& Elsevier]

The dolphin-like ichthyosaurs – also known as 'fish lizards' – are extinct marine reptiles that roamed the Mesozoic oceans for some 160 million years. As for most ancient vertebrates, our knowledge of these iconic animals largely derives from biomineralized hard parts (teeth and bones). However, soft tissues are also known from a number of Lagerstätte specimens, and have opened up new avenues for deciphering their biology and ecology. Herein, we present a review of ichthyosaur research and life style iconography with particular focus on soft-tissue structures and inferences made from these, including aspects of coloration and thermoregulation. We then distill novel insights on ichthyosaur anatomy and physiology gained from an exceptionally preserved, sub-adult specimen of the parvipelvian Stenopterygius from the Jurassic Posidonia Shale in Germany, and describe the process in which a detailed, three-dimensional reconstruction in scale 1:1 was produced. Our new sculpture is based on empirical evidence obtained directly from the fossil record, including uniquely preserved soft-tissue structures (e.g., original pigments and blubber), resulting in the scientifically most up-to-date reconstruction of an ichthyosaur currently available. [ABSTRACT FROM AUTHOR]

Morphometrics and blubber depths from all four high Antarctic seals (Weddell, Ross, crabeater, and leopard) were obtained during a midsummer research cruise in the Ross Sea as the physiological ecology component of the U.S. Antarctic Pack Ice Seals project. These data are the only in vivo measurements of all four species from the same location and time of year and focused on variances in morphometrics and blubber depth related to species, sex, and age. By controlling for location and season, this cross-species design provided the means to differentiate how blubber mass might be influenced in these groups. We measured both absolute blubber depth and ratio of blubber depth to body core diameter. We found that adult and younger animals showed differences in blubber depth, but male versus female seals did not show differences within any given species. However, when compared across species, the ratio of blubber ring depth to body core diameter suggests that adult Weddell seals differ in their use of blubber compared with the other three species. We propose that this difference in blubber pattern is most likely related to Weddell nutritional requirements during the breeding season having a greater influence on blubber depth than thermal requirements when compared with the other three species. [ABSTRACT FROM AUTHOR]

Organohalogen contaminants including PCBs, DDTs, CHLs, HCHs, HCB, PBDEs and HBCDs were determined in striped dolphins (Stenella coeruleoalba) found stranded at Gogo-shima (n =6, 2003) and collected from Taiji (n =15, 1978–1992) in Japan. All target compounds were significantly detected in all the specimens, indicating ubiquitous contamination of oceanic cetaceans in northwest Pacific Ocean. Examination of body distribution of organohalogens in the six specimens from Gogo-shima showed no significant difference in concentrations among the analyzed tissues, except for brain, which had lower levels possibly due to the existence of blood–brain barrier. For evaluating temporal trends, archived blubber samples of adult male stripped dolphins collected in 1978, 1979, 1986 and 1992 were analyzed. Concentrations of PCBs, DDTs and HCHs did not change significantly during 1978–2003. In contrast, remarkable increasing trends of PBDEs and HBCDs were observed, suggesting growing consumption in Japan and surrounding countries in recent years. [Copyright &y& Elsevier]

Validation of a high-throughput measurement system with microwave-assisted extraction (MAE), fully automated sample preparation device (SPD), and gas chromatography-electron capture detector (GC-ECD) for the determination of polychlorinated biphenyls (PCBs) in minke whale blubber was performed. PCB congeners accounting for >95% of the total PCBs burden in blubber were efficiently extracted with a small volume (20mL) of n-hexane using MAE due to simultaneous saponification and extraction. Further, the crude extract obtained by MAE was rapidly purified and automatically substituted to a small volume (1mL) of toluene using SPD without using concentrators. Furthermore, the concentration of PCBs in the purified and concentrated solution was accurately determined by GC-ECD. Moreover, the result of accuracy test using a certified material (SRM 1588b; Cod liver oil) showed good agreement with the NIST certified concentration values. In addition, the method quantification limit of total-PCB in whale blubbers was 41ngg−1. This new measurement system for PCBs takes only four hours. Consequently, it indicated this method is the most suitable for the monitoring and screening of PCBs in the conservation of the marine ecosystem and safe distribution of foods. [Copyright &y& Elsevier]

We report concentrations of several classes of organochlorines (OCs) in the blubber of California sea lions ( Zalophus californianus) from the Gulf of California. Summed OC levels measured in 34 wild-ranging animals were, in general, lower than those previously reported in sea lions from the eastern Pacific. The rank order of OCs was ΣDDTs (mean = 3400 ng g−1 lipid weight [lw]) > ΣPCBs (1400 ng g−1 lw) > ΣHCHs (50 ng g−1 lw) ≥ ΣCHLORs (46 ng g−1 lw). The most abundant OC measured was the DDT metabolite, p,p′-DDE. No significant differences in OC profiles were found between genders or rookeries. Although the mean concentrations of OCs measured in adult males and females were similar, only adult females had significantly higher ( p < 0.05) mean blubber concentrations of ∑DDTs and ∑HCHs than pups. [ABSTRACT FROM AUTHOR]

In an earlier paper, we reported data indicating a sharp increase in hexabromocyclododecane concentrations in the blubber of 85 harbor porpoises from the UK, from about 2001 onward. That time trend was evaluated using data from 1994-2003, generated on a diastereoisomer basis using LC-MS. In this paper we report additional data for 138 animals collected during 2003-2006. ΣHBCD concentrations ranged from <10 to 11,500 μg kg-1 wet weight (up to 12,800 μg kg-1 lipid weight) and TBBP-A was not detected in any samples. The maximum ΣHBCD concentration observed in this study was about half that seen in the earlier study (21,400 μg kg-1 lipid weight) and, in both studies, the highest concentration was for an animal stranded or by caught in 2003. Investigation of time trends confirmed a statistically significant increase between 2000 and 2001 (p <0.01) and a statistically significant decrease between 2003 and 2004 (p < 0.05). Neither trend was confounded by age, sex, nutritional status, or location. Possible contributory factors to the observed decrease include the closure in 2003 of an HBCD manufacturing plant in NE England which had considerable emissions up to 2003, and two voluntary schemes intended to reduce emissions of HBCD to the environment from industry which, however, did not formally begin until 2006. [ABSTRACT FROM AUTHOR]

A sensitive and selective method utilizing high performance liquid chromatography coupled to negative atmospheric pressure chemical ionization tandem mass spectrometry (APCI-LC/MS/MS) was developed to enable analysis of selected natural persistent organohalogens accumulated in marine biota. The analytes were three methoxylated tetrabromodiphenyl ethers (6-MeO-BDE47, 2'-MeO-BDE68, and 2',6-diMeO-BDE68), a dimethoxylated tetrabromobiphenyl (2,2'-diMeO-BB80), and two halogenated methyl bipyrroles (Cl7-MBP and Br4Cl2-DBP). These products were well resolved on a 150 mm reversed-phase column with methanol as the mobile phase. The fragmentation pathways of the Cl7-MBP and Br4Cl2-DBP produced characteristic multiple reaction monitoring (MRM) transitions. Determination was performed in the MRM mode using phenoxide ion [M-Br+O]- and product Br- ions for MeO-BDE analogues, or the precursor [M-Cl+O]- to Br- ion for Br4Cl2- DBP, and to C4NCl4- ion for Cl7-MBP. The APCI-LC/MS/ MS method is acceptable for calibration of the linearity and repeatability of all products studied in the low ng/g (lipid weight) level and with similar sensitivity to the electron ionization (EI)-GC/MS method. The proposed method was applied for quantification of natural organohalogens accumulated in melon-headed whale (Peponocephala electra) blubber (N = 15) in the Asia-Pacific Ocean. The concentration was positively correlated between different groups of compounds except for 2'-MeO-BDE68. The use of the analytical method based on negative ion APCI-LC/MS/MS would provide a new way for rapid monitoring of halogenated natural products from marine biota, such as sponges or algae. [ABSTRACT FROM AUTHOR]

The maternal-fetal transfer and subsequent uptake of sow milk enriched with n-6- or n-3-polyunsaturated fatty acids may not only influence neonatal body fat but may also have an impact on the immune function of newborn piglets. Sows were fed a diet containing sunflower oil as n-6-source or oil from seal blubber with long chain polyunsaturated n-3-fatty acids during pregnancy and lactation. Sow serum was investigated during pregnancy and serum and milk during lactation; piglet serum and liver were investigated in the suckling period until day 19. Piglet leukocyte subpopulations were characterised by flow cytometry and leukocyte proliferation was tested after stimulation with mitogens. No differences were noted in performance. The serum and milk fatty acid status of the sows was markedly influenced by the diet. Eicosapentaenoic acid (20:5n-3), 22:5n-3 and 22:6n-3 were higher (p < 0.001) in serum and liver of piglets delivered from sows fed the seal blubber oil. Piglets at birth had lower lymphocyte counts (p < 0.01) than piglets 19 days after birth. However, no influence of feeding the different oil sources was noted on lymphocyte phenotyping and leukocyte proliferation test. The results of the present study show that the maternal diet affected the fatty acid status of neonates, but much more in the sucking period. Immunological traits were not affected, probably as the mononuclear cell lineage is too immature around birth. Effects of PUFA n-3 might only be seen at a later time point or in the polymorphonuclear cell lineage as they were dominating right after birth. [ABSTRACT FROM AUTHOR]

Polybrominated diphenyl ethers (PBDEs) were analyzed in blubber of harbor seals (Phoca vitulina concolor) collected between 1991 and 2005 along the northwest Atlantic. ∑PBDE concentrations (mono- to hexa-BDEs) detected in blubber samples (n =42) ranged from 80 to 25720ngg−1 lw, (overall mean 2403±5406ngg−1 lw). By age, mean ∑PBDE concentrations were: 3645±7388, 2945±5995, 1385±1265, and 326±193ngg−1 lw in pups, yearlings, adult males, and adult females, respectively. Unlike the trend for PCBs, no decreasing gradient from urban to rural/remote areas was observed for PBDEs in these samples, likely reflecting inputs from local sources. No significant temporal trend was observed for PBDEs in harbor seals between 1991 and 2005, although congener profiles shifted over time. Tetra-BDE-47 was the dominant congener, followed by BDEs-99, -100, -153, -154, and -155 in varying order, suggesting exposure to the penta-BDE product. In adult males, the hexa-BDEs contributed more to the total (22%) than BDEs-99 and -100 (14%), and concentrations of BDE-155 were elevated compared with -154. Higher BDEs were detected in a subset of seals (n =12) including hepta-BDE-183, the marker for the octa-BDE mixture, and octa-BDE-197, along with several unidentified hepta- and octa- congeners. BDE-209 was detected in seal blubber at concentrations ranging from 1.1 to 8ngg−1 lw, indicating that deca-BDE is bioavailable in this marine food web. This is the first study to document the accumulation of BDE-209 at measurable levels in wild harbor seals. While the PBDE patterns in blubber indicate exposure to all three BDE commercial mixtures, the data also suggest that BDE-209 debromination by seal prey fish may contribute to the loading of lower brominated congeners (hexa- to octa-BDEs) in these seals. [Copyright &y& Elsevier]

Mammals balance heat dissipation with heat production to maintain core body temperatures independent of their environment. Thermal balance is undoubtedly most challenging for mammals born in polar regions because small body size theoretically results in high surface-area-to-volume ratios (SA : V), which facilitate heat loss (HL). Thus, we examined the ontogeny of thermoregulatory characteristics of an ice-breeding seal (Weddell seal Leptonychotes weddelli). Morphology, blubber thickness, rectal temperature (Tr), muscle temperature (Tm), and skin temperatures on the trunk (Ts) and flipper (Tf) in 3-5-wk-old pups, yearlings, and adults were measured. Adults maintained the thickest blubber layers, while yearlings had the thinnest; Tr and Tm fell within a narrow range, yet Tr and Tm decreased significantly with body length. All seals maintained skin temperatures lower than Tr, our index of core body temperature. The Ts's were positively correlated with environmental temperatures; conversely, Tf's were not. Although pups had the greatest proportion of blubber, their greater SA : V and limited ability to minimize body-to-environment temperature gradients led to the greatest calculated mass-specific HL. This implies that pups relied on elevated metabolic heat production to counter HL. Heat production in pups and yearlings may have been aided by nonshivering thermogenesis in the skeletal muscle via the enhanced muscle mitochondrial densities that have been observed in these segments of this population. [ABSTRACT FROM AUTHOR]

Abstract: Polybrominated diphenyl ethers (PBDEs) and organochlorine compounds (OCs) were determined in the blubber of 55 melon-headed whales (Peponocephala electra) mass stranded along the Japanese coasts since 1982. DDTs and PCBs were predominant in all the specimens investigated. In whales that died during the latest event in 2006, concentrations of PBDEs (190–510ng/g lipid wt) were approximately two orders of magnitude lower than DDTs and PCBs, but comparable with HCHs and HCB. Maternal transfer of PBDEs to offspring through the whole reproductive process was estimated to be 85% of the mother''s body burden, while that occurring during gestation was much lower (2.6–3.5%). Concentrations of PCBs, DDTs, and HCB were lower in melon-headed whales stranded after the year 2000 than those stranded in 1982, whereas PBDE and CHL levels showed a temporal increase during the past 20years, suggesting that the peak of their usage and contamination occurred after the year 1982. [Copyright &y& Elsevier]

Fatty acid profiles of blubber have been shown previously to provide information on stock structure and sex differences. Generally the predominant blubber lipid of marine mammal species is triacylglycerol (fatty acids linked to glycerol) and previous studies have focused on this lipid class. But in some species such as the sperm whales the predominant lipid is wax esters (fatty acids linked to fatty alcohols) although triacylglycerols are also present. In this study the fatty acids and fatty alcohols of these lipid classes were characterized and the fatty acid profiles compared in order to assess their potential to provide qualitative ecological data.Biopsy samples were obtained from 40 whales found in seas around the Azores achipelago during the period 2002–2003. The samples contained about 10% lipid of which 70% was wax ester and 11% triacylglycerol. The fatty acids of the triacylglycerols and wax esters were respectively approximately 19% and 16% saturated, 74% and 80% monounsaturated and 5% and 3% polyunsaturated with the main contributors being 18:1n-9, 16:1n-7 and 16:0. The alcohols of the wax esters were mainly either saturated or monounsaturated with the main contributors being 18:1n-9 (40%) and 16:0 (22%). No statistically significant differences in profiles were found between different island groups, between sexes or between years of sampling. In future studies there would not appear to be any apparent benefits over total lipid in examining each of the fatty acid classes of sperm whale blubber separately. [ABSTRACT FROM PUBLISHER]

The elimination kinetics of polychlorinated biphenyls (PCBs) in humans is difficult to assess in observational studies, because PCB exposure is never completely abolished. In a community with high dietary PCB exposures from whale blubber, we examined two groups of children with increased body burdens from breast-feeding. Follow-up was from ages 4.5 to 7.5 years (99 subjects) and 7 to 14 years (101 subjects). The calculations were performed by the use of structural equation models, with adjustment for body weight and dietary blubber intake as the main source of postnatal exposure. As a likely result of background exposures, apparent elimination half-lives were unexpectedly long when based on results from all cohort members. Subjects with exposures above the median and in the highest quartile showed half-lives of about 3-4 years for CB-138 and 4.5-5.5 years for CB-105 and CB-118; 6.5-7.5 years for CB-156, CB-170, and CB-187; and 7-9 years for CB-153 and CB-180. The longest half-lives correspond to elimination of the parent PCB solely with a daily fat excretion rate of 1-2 g, whereas shorter half-lives assume metabolic break-down. [ABSTRACT FROM AUTHOR]

Marine mammals from Queensland, Australia, are bioaccumulating elevated concentrations of a range of polybrominated natural products. In this study, we detected three new polybrominated dimethoxybiphenyls (PBDMBs) in the blubber of selected marine mammal samples which were identified as 2,6′-dimethoxy-3,3′,5-tribromobiphenyl (2,6′-diMeO-BB 36), 2,2′-dimethoxy-3,3′-dibromobiphenyl (2,2′-diMeO-BB 36), and 6,6′-dimethoxy-3,3′-dibromobiphenyl (6,6′-diMeO-BB 11). These three PBDMBs are structurally related to the known natural product 2,2′-dimethoxy-3,3′,5,5′-tetrabromobiphenyl (2,2′-diMeO-BB 80). In the first part of this study, 2,2′-diMeO-BB 80 was photochemically debrominated under UV irradiation. This resulted in seven of eight possible mono- to triBDMBs as debromination products. In the second part of this study, the structure of all PBDMBs debromination products was investigated. This was supported by synthesis of two diBDMB and one triBDMB via bromination and subsequent methylation of 2,2′-biphenyldiol. Structures of the remaining PBDMBs were tentatively assigned by considering the retention times, mass spectra and amounts formed during UV irradiation of 2,2′-diMeO-BB 80 . In the third part of this study, blubber of marine mammals from Australia was analysed for PBDMBs using gas chromatography in combination with electron ionization mass spectrometry (GC/EI-MS) in the selected ion monitoring mode. In these samples, 2,2′-diMeO-BB 80 was found at concentrations of 200–1800ngg−1 lipid weight (lw). The latter represents the highest concentration reported for this compound in environmental samples. 6,6′-diMeO BB 11, 2,2′-diMeO BB 36, and 2,6′-diMeO BB 36 were present at ∼7ngg−1 lipids, or 0.43–1.5% of diMeO-BB 80. No further PBDMBs were detected in the samples. The di- and triBDMBs identified in marine mammal blubber have not been reported as natural products. They may represent either new natural products or transformation products of 2,2′-diMeO-BB 80. [Copyright &y& Elsevier]

The article presents a study which investigated the potential of elemental concentrations in bowhead whales epidermal samples to anticipate the element concentrations in blubber, kidney, liver, and muscle. It revealed that epidermal biopsy cannot predict elemental concentrations in blubber, kidney, liver, and muscle in bowhead whales. The study suggested that in evaluating element concentrations of cetaceans, the researchers should establish a sound scientific basis before employing epidermal biopsies to forecast internal tissue concentrations of elements.

A major source of energy during lactation in mammals is provided through the mobilization of blubber fatty acids (FAs). We investigated the extent to which FAs were mobilized to support both maternal metabolic requirements and milk production in the Weddell seal and how this was reflected in the FA composition of the pup's blubber at the end of lactation (EL). FA composition of postpartum female blubber was similar in the 2 yr of study (2002 and 2003) but differed markedly by EL. Pup blubber FAs (at EL) were also different between years and did not match that of the mother's milk or blubber. Milk FA composition changed during lactation, which may have been a reflection of an increase in pup energy demands at different stages of development. In addition, there was evidence of feeding by some females during lactation, with higher levels of some FAs in the milk than in the blubber. Our results indicate that differential mobilization of FAs occurred in lactating Weddell seals and that this was related to total body lipid stores at postpartum. Furthermore, growing pups did not store FAs unmodified unmodified, providing evidence that selective use does occur and also that using FA composition to elucidate dietary sources may be problematic in growing individuals. [ABSTRACT FROM AUTHOR]

Blubber was analyzed for a wide range of contaminants from five subadult and eight adult male ringed seals sampled in 2004, namely, for polychlorinated biphenyls (PCBs), hexachlorobenzene (HCB), toxaphenes, chlordanes, dichlorodiphenyldichloroethylene (DDE), and polybrominated diphenylethers (PBDEs). Contaminant levels were compared to previously sampled animals from the same area, as well as data from literature for other arctic wildlife species from a wide variety of locations. Ringed seals sampled in 2004 showed 50-90% lower levels of legacy contaminants such as PCBs and chlorinated pesticides compared to animals sampled in 1996 of similar age (14 subadults and 7 adult males), indicating that the decline of chlorinated contaminants observed during the 1990s in a variety of arctic wildlife species is continuing into the 21st century. The results also indicated that PBDE declined in ringed seals; levels in 2004 were about 70-80% lower than in animals sampled in 1998. This is one of the first observations of reduced exposure to these compounds and might be a first indication that restrictions of production and use of these contaminants have resulted in lower exposures in the Arctic. The PCB pattern shifted toward the less chlorinated (i.e., less persistent) PCBs, especially in adult ringed seals, possibly as a result of reduced overall contaminant exposures and a consequently lower cytochrome P-450 (CYP) induction, which results in a slower metabolism of less persistent PCBs. The overall effect would be relative increases in the lower chlorinated PCBs and a relative decreases in the higher chlorinated PCB. Possibly due to low exposure and consequent low induction levels, ethoxyresorufin O-deethylation (EROD) activity proved to be a poor biomarker for contaminant exposure in ringed seals in the present study. The close negative correlation (r2 = 70.9%)between EROD activity and percent blubber indicates that CYP might respond to increased bioavailability of the contaminant mixtures when they are mobilized from blubber during periods of reduced food intake. [ABSTRACT FROM AUTHOR]

This study of vertical fatty acid profiles, based on analysis of 58 fatty acids sampled at 3-mm intervals throughout the blubber column of a model marine mammal, the ringed seal (Pusa hispida), revealed three chemically distinct layers. The average depths of the outer and inner layers were quite consistent (~1.5 and ~1 cm, respectively). Consequently, the middle layer varied greatly in thickness, from being virtually absent in the thinnest animals to 2.5 cm thick in the fattest. The relative consistencies of the thickness and composition of the layers as well as the nature of the fatty acids making up each layer support the generally assumed function of the various layers: (1) the outer layer is primarily structural and thermoregulatory, (2) the inner layer is metabolically active with a fatty acid composition that is strongly affected by recent/ongoing lipid mobilization/deposition, and (3) the middle layer is a storage site that contracts and expands with food availability/consumption. The remarkable dynamics of the middle layer along with the discrete pattern of stratification found in the vertical fatty acid profiles have important implications for methodological sampling design for studies of foraging ecology and toxicology based on analyses of blubber of marine mammals. [ABSTRACT FROM AUTHOR]

We measured the concentrations of butyltin (BT) and phenyltin (PT) compounds in blubber, liver, lung, and muscle of seven stranded killer whales ( Orcinus orca) collected from Rausu, Hokkaido, Japan. BTs in blubber ( n = 6), liver ( n = 4), lung ( n = 1), and muscle ( n = 4) of adult whale were in the range of 37–90, 385–676, 15, and 26–53 μg kg−1 wet weight, respectively. Concentrations of PTs in blubber, liver, lung, and muscle were <1 to 58, <1 to 14, 7 and <1 to 4 μg kg−1 wet weight, respectively. Detected frequencies of PTs were low in all tissues. Higher percentages of monobutyltin (MBT) in blubber, lung, and muscle were observed, while the percentage of dibutyltin (DBT) was high in liver. Detected frequencies of triphenyltin (TPT) were highest among tissues. Total BT concentrations in blubber and liver of a whale calf were lower than those in adult whales. MBT and DBT in the liver of the calf were the same (42%). MBT in blubber was the dominant compound among BTs. [ABSTRACT FROM AUTHOR]

California sea lions have high levels of persistent organic pollutants (POPs) in their blubber. Animals affected by domoic acid fast and refeed during their rehabilitation. We studied the effect of decreases in total body mass (16 ± 7% of initial body mass) on blubber POP contaminant concentrations and estimated POP burdens during fasting (12 ± 5 days) in 19 California sea lions. The effect of refeeding (92 ± 8% of initial body mass) was also investigated. Significant increases in the concentration of all POPs were found over the mass loss period and decreases during mass gain. A basic mass balance model indicated that the changes did not conform to a simple concentrating and diluting pattern and a proportion of the contaminants were lost from the lipid pool During mass loss, the lower chlorinated polychlorinated biphenyl congeners, chlordanes, and hexachlorocyclohexanes were lost at a higher rate than the other contaminant classes (particularly polybrominated diphenyl ethers). During mass gain the behavior of all contaminant classes was more consistent with the dilution model. These results indicate the importance of considering the energetic context when sampling blubber for long-term contaminant monitoring and suggest an initial approach to adjust for such differences. [ABSTRACT FROM AUTHOR]

Coastal marine resources are at risk from anthropogenic contaminants, including legacy persistent organic pollutants (POPs) with half-lives of decades or more. To determine if polychlorinated biphenyl (PCB) signatures can be used to distinguish among local populations of inshore bottlenose dolphins (Tursiops truncatus) along the southeastern U.S. coast, blubber from free-ranging and stranded animals were collected along the Georgia coast in 2004 and analyzed for PCB congeners using gas chromatography with electron capture and negative chemical ionization mass spectrometric detection (GC-ECD and GC-NCI-MS). Mean total PCB concentrations (77±34 μg/g lipid) were more than 10 fold higher and congener distributions were highly enriched in Cl7–Cl10 homologs in free-ranging animals from the Turtle/Brunswick River estuary (TBRE) compared with strandings samples from Savannah area estuaries 90 km to the north. Using principal components analysis (PCA), the Aroclor 1268 signature associated with TBRE animals was distinct from that observed in Savannah area animals, and also from those in animals biopsied in other southeastern U.S estuaries. Moreover, PCB signatures in dolphin blubber closely resembled those in local preferred prey fish species, strengthening the hypothesis that inshore T. truncatus populations exhibit long-term fidelity to specific estuaries and making them excellent sentinels for assessing the impact of stressors on coastal ecosystem health. [Copyright &y& Elsevier]

Blubber of seals, harbour porpoises and fish originating from the North Sea, the Baltic Sea, as well as coastal waters of Iceland and North America were analyzed for residues of polybrominated biphenyls. According to GC/ECNI-MS, hexabromobiphenyls (hexaBBs) dominated in the samples, followed by pentabromobiphenyls (pentaBBs) and heptabromobiphenyls (heptaBBs), whereas octabromobiphenyls (octaBBs) were only detected in selected samples and nonabromobiphenyls (nonaBBs) and PBB 209 were not found at all. Eleven peaks of hexaBBs—two peaks might have been each composed of two congeners, respectively—were detected in the different samples. The hexaBB pattern in samples of Iceland was a mixture of the pattern determined in samples from North America and continental Europe. In samples from the European continent, the major congener in technical hexabromobiphenyl, PBB 153, accounted for 11–37% of the hexaBBs. Other prominent isomers were PBB 155 (7.1–64%) and PBB 154 (11–33%), followed by PBB 133 as well as PBB 132 and/or PBB 146. Most of these PBBs were determined for the first time in marine biota and must be metabolites of higher brominated PBBs since they were not present in any technical product. PBB 153 was dominant in blubber of marine mammals from North America (92–96%). Blubber of harbour porpoises and also seal milk showed more peaks, which is indicative of a lower capability of biotransforming PBBs. It is concluded from this and other studies that PBB residues in North America are mainly originating from technical hexabromobiphenyl, while the bulk of the PBB residues in the European marine samples originated from technical octa- and decabromobiphenyl. Finally, it is evident from this study that a global ban of PBBs should not only be restricted to hexabromobiphenyls, but also needs to include higher brominated mixtures. [Copyright &y& Elsevier]

The article discusses the levels of organochlorine compounds found in the blubber and livers of bottlenose dolphins from the Canary Islands. The authors measured the concentrations of PCBs DDT and metabolites as well as chlordanes (CHLs), dieldrin, and hexaclorobenzene (HCB). They found the levels of PCBs and DDT were similar to those found in the same species in the North of Europe. They concluded that the levels of DDE associated with adverse effects found in marine mammals were close to those found in adult male bottlenose dolphins.

Persistent organic pollutants including organochlorine pesticides, PCBs, and PCDDs/DFs were determined in the blubber of Caspian seals, which died during an outbreak of canine distemper virus in 2000 and 2001. DDTs were the predominant contaminants that ranged from 3.1 to 560μg/g lipid. A negative correlation was observed between concentration of contaminants and blubber thickness. During spring, as the blubber layer becomes thin after breeding and moulting, seals may face higher risk due to the increased concentration of organochlorines in their bodies. TEQs in the blubber of Caspian seals (10–340pg TEQ/g) were lower than those in seals from other locations, suggesting that toxic effects of these contaminants are a deal less in the present population and they are unlikely to be linked to mass mortality. The levels of PCBs and pesticides in Caspian seals, however, comparable to those in other aquatic mammals that have suffered from epizootics, might pose a risk of immunosuppression. [Copyright &y& Elsevier]

Lower chlorinated PCBs can damage DNA directly or via free radical mechanisms. In order to assess the DNA-damaging potential of PCBs in humans, blood samples were collected from Inuit population from Salluit, Northern Canada. Their diet comprises blubber from sea mammals and fatty fish, which accumulate non-biodegradable PCBs at varying levels. The 103 samples thus collected were categorized into low-, medium- and high-PCB exposure groups. A comprehensive 32P-postlabeling adductomics technology, which allows measure differences in DNA adduct profiles of polar and lipophilic adducts between control and exposure groups, was applied to these samples to assess the effect of PCB on DNA damage. The adduct patterns obtained were qualitatively similar to other human tissues studied previously. A range of highly polar to lipophilic subgroups of adducts were detected. The known oxidative lesion, 8-oxodG was predominant. While some individual adducts appear to accumulate with increasing PCB levels, a definitive association could not be made. A possible confounder effect of selenium is discussed. [Copyright &y& Elsevier]

Seven West Greenland sledge dog bitches (Canis familiaris) and their three pups were fed 50–200g of contaminated West Greenland minke whale (Balaenoptera acutorostrata) blubber, and in a control cohort eight sister bitches and their five pups were fed a similar amount pork fat. Blood plasma and urine clinical–chemical parameters were measured and compared between the bitches and pups form the control and exposed cohorts. Based on existing reference intervals, Arctic mammals may have blood clinical–chemical endpoint levels that differ from comparable species at lower latitudes. The cortisol:creatinine ratio, protein:creatinine ratio, alkaline phosphatase, cholesterol and inorganic phosphate were significantly highest (ANCOVA: all ) in the pup generation. The cortisol:creatinine ratio, cholesterol, lactate dehydrogenase and creatinine kinase were significantly higher (ANCOVA: all ) in the control group, while glucose was significantly highest (ANCOVA: ) in the exposed group. Furthermore, the blood cholesterol levels indicate that exposure via the diet to marine mammal blubber has a preventive effect on the development of cardiovascular diseases. We therefore suggest that the consumption of contaminated Arctic marine blubber impacted liver and kidney function in adult and pup sledge dogs. [Copyright &y& Elsevier]