Levels of organochlorine and polycyclic aromatic compounds in harp seal beaters (Phoca groenlandica)

Trophic transfer of polycyclic aromatic hydrocarbons in marine mammals based on isotopic determination

The tissue distribution (liver, kidney, heart, lung, and muscle), source, and trophic transfer of 15 polycyclic aromatic hydrocarbons (PAHs) were studied on 14 stranded East Asian finless porpoises (Neophocaena asiaeorientalis sunameri), 14 spotted seals (Phoca largha), and 9 stranded minke whales (Balaenoptera acutorostrata) from Yellow Sea and Liaodong Bay. The PAHs levels ranged from below the limit of detection to 459.22 ng g^-1 dry weight in the tissues of the three marine mammals, and light molecular weight PAHs were the primary pollutants. Although the PAHs levels were relatively higher in internal organs of the three marine mammals, generally no tissue-specific distribution of the PAHs congeners was found, either for gender-specific distribution of PAHs in the East Asian finless porpoises. However, species specific PAHs concentration distribution were obtained. The PAHs were mainly originated from petroleum and biomass combustion in the East Asian finless porpoises, while those for the spotted seals and minke whales were complex. Trophic level associated biomagnification was found for phenanthrene, fluoranthene, and pyrene in the minke whale. Benzo(b)fluoranthene exhibited a significant biodilution with increasing trophic levels in the spotted seals, but the total concentration of the PAHs showed a significant biomagnification with increasing trophic levels. Trophic level-associated biomagnification of acenaphthene, phenanthrene, anthracene, and ∑PAHs were found in the East Asian finless porpoise, while pyrene exhibited obvious biodilution with increasing trophic levels. Our current study filled knowledge gaps on tissue distribution and trophic transfer of the PAHs in the investigated three marine mammals.

Interactions of Dichlorodiphenyltrichloroethane (DDT) and Dichlorodiphenyldichloroethylene (DDE) With Skeletal Muscle Ryanodine Receptor Type 1

Dichlorodiphenyltrichloroethane (DDT) and its metabolite dichlorodiphenyldichloroethylene (DDE) are ubiquitous in the environment and detected in tissues of living organisms. Although DDT owes its insecticidal activity to impeding closure of voltage-gated sodium channels, it mediates toxicity in mammals by acting as an endocrine disruptor (ED). Numerous studies demonstrate DDT/DDE to be EDs, but studies examining muscle-specific effects mediated by nonhormonal receptors in mammals are lacking. Therefore, we investigated whether o,p'-DDT, p,p'-DDT, o,p'-DDE, and p,p'-DDE (DDx, collectively) alter the function of ryanodine receptor type 1 (RyR1), a protein critical for skeletal muscle excitation-contraction coupling and muscle health. DDx (0.01-10 µM) elicited concentration-dependent increases in [3H]ryanodine ([3H]Ry) binding to RyR1 with o,p'-DDE showing highest potency and efficacy. DDx also showed sex differences in [3H]Ry-binding efficacy toward RyR1, where [3H]Ry-binding in female muscle preparations was greater than male counterparts. Measurements of Ca2+ transport across sarcoplasmic reticulum (SR) membrane vesicles further confirmed DDx can selectively engage with RyR1 to cause Ca2+ efflux from SR stores. DDx also disrupts RyR1-signaling in HEK293T cells stably expressing RyR1 (HEK-RyR1). Pretreatment with DDx (0.1-10 µM) for 100 s, 12 h, or 24 h significantly sensitized Ca2+-efflux triggered by RyR agonist caffeine in a concentration-dependent manner. o,p'-DDE (24 h; 1 µM) significantly increased Ca2+-transient amplitude from electrically stimulated mouse myotubes compared with control and displayed abnormal fatigability. In conclusion, our study demonstrates DDx can directly interact and modulate RyR1 conformation, thereby altering SR Ca2+-dynamics and sensitize RyR1-expressing cells to RyR1 activators, which may ultimately contribute to long-term impairments in muscle health.

Anthropogenic Effects on Natural Mammalian Populations: Correlation Between Telomere Length and Coal Exposure

The Candiota coal mine in Rio Grande do Sul (RS) is one of the largest in Brazil. Coal is a fossil fuel that causes environmental impacts from its extraction to combustion due to the release of different agents, such as polycyclic aromatic hydrocarbons (PAH) and heavy metals. Ctenomys torquatus are herbivorous and subterranean rodents that dig tunnels with their paws and teeth and can be exposed to coal through contaminated food. Exposure to pollutants can cause DNA damage and affect different tissues, inducing alterations in the population structure and genetic diversity. Our study aimed to evaluate the effect of exposure to coal and its derivatives on the C. torquatus population and to examine the relationship of coal exposure with variations in absolute telomere length (aTL), global DNA methylation and genotoxicity. Our study showed an inverse correlation between telomere length and coal exposure in addition to an increase in DNA damage. The results indicate that coal and its byproducts can contribute to the alteration of the C. torquatus population structure, as evidenced by a reduction in the number of adults.

Accumulation of PAHs and synthetic musk compound in minke whales (Balanoptera acutorostrata) and long-beaked common dolphins (Delphinus capensis) from Korean coastal waters

Information on the occurrence and accumulation profiles of polycyclic aromatic hydrocarbons (PAHs) and synthetic musk compounds (SMCs) in marine mammals is scarce. In the present study, we recorded the concentrations and profiles of PAHs and SMCs in liver tissue and blubber from minke whales and common dolphins from Korean coastal waters. The overall concentrations of PAHs and SMCs in blubber from both cetacean species were approximately three to five times higher than those in liver tissues. Residue levels of PAHs were lower, whereas levels of SMCs were relatively higher than those reported in other studies. Lack of species- and sex-dependent differences in the concentrations of PAHs and SMCs were found. Naphthalene and 1,3,4,6,7,8-hexahydro-4,6,6,7,8,8-hexamethylcyclopenta-r-2-benzopyran (HHCB) were predominant compounds in all the samples for PAHs and SMCs, respectively. The concentrations of PAHs and SMCs were significantly correlated with each other, but were not correlated with body size of cetaceans. The present data provide valuable information on the exposure of Korean cetaceans to PAHs and SMCs.

Occurrence and accumulation patterns of polycyclic aromatic hydrocarbons and synthetic musk compounds in adipose tissues of Korean females

Very few studies have reported on the occurrence and accumulation profiles of polycyclic aromatic hydrocarbons (PAHs) and synthetic musk compounds (SMCs) in human adipose tissue. In this study, concentrations of PAHs and SMCs in adipose tissues collected from Korean women in 2007 and 2008 were determined. Total concentrations of PAHs and SMCs in adipose tissues ranged from 15 to 361 (mean: 119) ngg(-1) lipid weight and from 38 to 253 (mean: 106) ngg(-1) lipid weight, respectively. Concentrations of SMCs in Korean adipose tissues were lower than those reported for European countries and the United States. Naphthalene was the most predominant PAH and HHCB was the dominant SMC found in adipose tissues. The concentrations of PAHs and SMCs were not correlated with each other, suggesting that the sources of human exposure to these two classes of compounds are different. No correlation was found between donor's age and residue levels of PAHs and SMCs. The results of this study provide baseline information on exposure of PAHs and SMCs to the general population in Korea.

Occurrence and accumulation features of polycyclic aromatic hydrocarbons and synthetic musk compounds in finless porpoises (Neophocaena phocaenoides) from Korean coastal waters

Reports of the occurrence and accumulation patterns of polycyclic aromatic hydrocarbons (PAHs) and synthetic musk compounds (SMCs) in marine mammals are scarce. In this study, the concentrations and accumulation profiles of PAHs and SMCs were determined in blubber from finless porpoises in Korean coastal waters. Total concentrations of PAHs and SMCs ranged from 6.0 to 432 (mean: 160) ng/g lipid weight and from 17 to 144 (mean: 52) ng/g lipid weight, respectively. Residue levels of PAHs were lower than those reported from other studies, while residue levels of SMCs were relatively higher than those reported in other studies. Naphthalene was the most abundant PAH and HHCB was the dominant SMC observed in finless porpoises. The concentrations of PAHs and SMCs were not correlated with each other, but were significantly correlated within the same chemical groups. No correlations were found between body size and residue levels of PAHs and SMCs.

Recent contamination by persistent organochlorines in Baikal seal (Phoca sibirica) from Lake Baikal, Russia

Blubber samples of Baikal seals pups (Phoca sibirica) collected in 2001 and 2002 were analyzed for persistent organochlorines (OCs) such as PCBs (polychlorinated biphenyls), DDTs (dichlorodiphenyltrichloroethane and its metabolites), HCHs (hexachlorocyclohexane isomers), CHLs (chlordane related compounds), TCPMe [tris(4-chlorophenyl)methane] and TCPMOH [tris(4-chlorophenyl)methanol]. The distribution pattern of OCs was in the following order: DDTs>PCBs>CHLs>HCHs>TCPMOH>TCPMe. Organochlorine concentrations and composition patterns in eight pup blubber samples (2002) analyzed in the present study were compared with the corresponding levels in juvenile Baikal seals from 1992 survey, and it was found that residue levels of OC compounds have declined during the 10 year period. In particular, concentrations of PCBs, HCHs and CHLs in seals collected in 2002 were approximately two times lower, while DDTs levels were three times lower than the corresponding levels in 1992. Furthermore, higher ratios of beta-HCH/HCHs and p,p(')-DDE/DDTs were found in 2002 samples. While comparing the OC levels with those in other seal pups it appeared that all the OC concentrations were lower than the levels in seals from coastal California known as one of the most polluted areas. PCB and DDT concentrations in the present specimens were higher than that in Arctic seal pups. The proportions of tri-, tetra-, penta- and hexachlorobiphenyls in pups captured in 2002 were higher than those in 1992. TEQ concentrations of non- and mono-ortho coplanar PCBs in Baikal seals collected in 2002 were higher than those in seals collected from some locations in the world, where human and industrial activities are extensive, suggesting potential for toxic implications of coplanar PCBs in Baikal seals.

Levels and chiral signatures of persistent organochlorine pollutants in human tissues from Belgium

Polychlorinated biphenyls (PCBs) and organochlorine pesticides (OCPs) were measured in human tissue samples including muscle, liver, brain, and kidney. The samples were obtained at autopsy in 2000-2001 from three women and eight men from Belgium, aged between 5 and 76 years. The measured PCBs included 23 ortho-substituted congeners and 3 non-ortho-substituted congeners (PCB 77, PCB 126, and PCB 169). The mean concentrations of SigmaPCBs were 29.4, 35.3, 10.6, and 11.8 ng/g wet wt in liver, muscle, kidney, and brain, respectively. HCB, gamma-HCH, beta-HCH, p,p'-DDE, and p,p'-DDD were found in all samples, while p,p'-DDT could only be found in one liver sample. The most abundant pesticide was p,p'-DDE. PCB 153 and PCB 180 were the main ortho-substituted congeners found in all the samples, while the concentration of the congeners with less than three chlorine atoms was below the limit of determination. In 10 of 18 tissues, the concentrations of PCB 169 were higher than the concentration of PCB 126. These results are consistent with the order of half-life of these congeners in humans and indicate that a steady state had been reached in these subjects. The enantiomeric compositions of alpha-HCH and chiral PCBs, including PCB 95, PCB 132, and PCB 149, were also measured. alpha-HCH was found to be racemic in three liver samples, while chiral PCB 95, PCB 149, and 132 showed racemic or nearly racemic compositions in muscle, kidney, and brain. Higher enatiomeric ratios (ERs) for the three chiral PCBs were found in liver samples. The mean (range) ERs in liver were 1.69 (1.04-2.97), 1.16 (0.99-1.41), and 0.74 (0.48-0.97) for PCB 95, PCB 149, and PCB 132, respectively.

Bioaccumulation of PCBs and chlorinated pesticides in seals, fishes and invertebrates from the White Sea, Russia

Persistent organochlorines (OC) contaminants, including polychlorinated biphenyl (PCB) congeners, Dichlorophenyltrichloroethane (DDT)- and chlordane (CHL) related compounds, hexachlorocyclohexanes (HCH) isomers and chlorobenzenes (CBz) were determined in blubber of harp seals (Phoca groenlandica), ringed seals (Phoca hispida) and bearded seals (Eringnathus barbatus) as well as in fishes and invertebrates from the White Sea, in northwest Russia. Highest summation operator PCB and summation operator DDT concentrations were found in samples from two male bearded seals (means of 4150 ng/g lw and 3950 ng/g lw, respectively). Female harp seals had mean summation operator PCB and summation operator DDT concentrations of 1070+/-504 ng/g lw and 619+/-328 ng/g lw, respectively. Male and female adult ringed seals had similar mean summation operator PCB concentrations as harp seals (955+/-385 ng/g lw and 999+/-304 ng/g lw, respectively). summation operator CHL concentrations ranged from 63+/-29 ng/g lw in blubber of female adult ringed seals, to 322+/-156 ng/g lw in adult harp seals and averaged 465 ng/g lw in bearded seals. HCH isomers, mirex and chlorobenzenes were detected in all seal samples but were present at lower levels than summation operator CHL, summation operator DDT and summation operator PCB. Concentrations of summation operator CHL, summation operator DDT and summation operator PCB in ringed seals from the White Sea were within the range reported for the Barents Sea but lower than in ringed seals from the Kara Sea. Temporal trends were investigated by comparing concentrations of OCs in blubber of harp seal pups collected in 1992 with pups of the same age collected in 1998. The declines over the 6 year period ranged from approximately 33% for summation operator DDT to 60% for summation operator PCB. These declines are consistent with reports of declining concentrations summation operator DDT in seawater from the White Sea and inflowing rivers in the 1980's and early 1990s. The major OC contaminants in fishes from the White Sea were DDT-related compounds and PCBs. Navaga (Eleginus navaga) had the highest concentrations of the 5 fish species studied with mean summation operator PCB of 41+/-6 ng/g wet wt. while lowest mean concentrations were present in cod muscle (16+/-8 ng/g ww). Concentrations of hexachlorobenzene (HCB), DDT, CHL-related compounds and PCB congeners were strongly correlated with trophic level of the organisms assigned using delta(15)N values, while beta-HCH, gamma-HCH and cis-chlordane showed no relationship with trophic level. Food web magnification factors (FWMFs) for p,p'-DDE, alpha-HCH, oxychlordane and trans-nonachlor the White Sea were similar to those from marine food webs in the Barents Sea and the Canadian arctic, while FWMFs for HCB and PCBs were generally lower. Overall the results suggest that the White Sea marine food differs in terms of the availability of contaminants in comparison to studies of open ocean arctic food webs due to proximity to urban/industrial areas and greater importance of benthic food sources.

Cytochrome P450 (CYP1A) induction and DNA adducts in a rat hepatoma cell line (Fao), exposed to environmentally relevant concentrations of organic compounds, singly and in combinations

Cytochrome P4501A (CYP1A) induction and DNA adduct formation were evaluated in the rat hepatoma cell line Fao, as biomarkers of exposure to organic compounds. Cells were exposed to environmentally relevant concentrations of benzo[a]pyrene (B[a]P) or 3,3',4,4'-tetrachlorobiphenyl (TCB), and to combinations of B[a]P and TCB. Both B[a]P and TCB induced CYP1A proteins in a concentration-dependent relationship, up to concentrations of 10 and 1 μM, respectively, detected by Western blotting. DNA adducts, analyzed by (32)P-postlabeling, were found at the highest concentrations of B[a]P (1 and 10 μM). No adducts were found in cells exposed to 0.1 μM TCB alone. The cotreatment of TCB and B[a]P indicated an increase in DNA adduct formation, compared with B[a]P, but no further induction of CYP1A protein compared with TCB alone. This study suggests that Western blotting and (32)P-postlabeling might be suitable methods for detecting CYP1A protein induction and DNA adducts, respectively, after exposure to environmentally relevant concentrations of organic compounds.

Polycyclic aromatic hydrocarbons (PaHs) in subcutaneous biopsies of Mediterranean cetaceans

The aim of the present study was to measure polycyclic aromatic hydrocarbon (PAH) levels in free-ranging Mediterranean cetaceans as they are likely to cause chemical stress in the organisms of this basin. Blubber samples were collected from live specimens of fin whales (Balaenoptera physalus) and striped dolphins (Stenella coeruleoalba) by means of biopsies, a non-destructive biological method. Fin whales were sampled in the Ligurian Sea, whereas striped dolphins were collected in the Ligurian and the Ionian Seas. A fingerprint of 14 PAHs was obtained for both species. In whales, the median value of total PAHs was 1970 ppb fresh weight (f.w.) while median carcinogenic PAH values were 89.80 ppb f.w.; in dolphins, the median values of total and carcinogenic PAHs were 29,500 and 676.00 ppb f.w., respectively. The different PAH values between the two species can be attributed to the different positions they take in the Mediterranean food web. The sampling period significantly influenced PAH concentrations of fin whales.

Organochlorine compounds and aliphatic hydrocarbons in Pacific walrus blubber

Blubber samples were collected from 8 male and 19 female Pacific walrus (Odobenus rosmarus divergens) taken during a 1991 joint USA/USSR cruise traveling widely through the Bering Sea. Dieldrin was found at a level similar to that reported 10 years earlier; oxychlordane was found at a slightly higher concentration than reported previously (Taylor et aL, 1989). Heptachlor epoxide was detected for the first time and found at a low concentration. An initial testing for alpha-, beta- and gamma-HCH detected concentrations similar to those in other Bering Sea pinnipeds. Mean summation of PCB was 0.45 microg g(-1) wet weight in males and 0.16 microg g(-1) in females; only one sample was > 1 microg g(-1). Traces of aliphatic hydrocarbons were detected in all sampled animals, only pristane (x = 0.48 microg g(-1)) was found in concentrations > 1 microg g(-1). Small sample sizes, a lack of samples from immature animals, and uniformly low concentrations of contaminants precluded meaningful analysis of age-related effects and regional differences.

Effects of chronic exposure to coal in wild rodents (Ctenomys torquatus) evaluated by multiple methods and tissues

Rio Grande do Sul (RS) coal is low quality and typically obtained by strip mining. In a recent study concerning 2 years of biomonitoring in coal regions, we demonstrated the genotoxicity of coal and related products on blood cells of native rodents, from RS, Brazil. With the goal of studying the variations in the effects of RS coal on different tissues of the same rodent, we utilized, besides the single cell gel (SCG) and micronucleus (MN) assay on blood, histological analyses and SCG assay of bone marrow, spleen, kidney, liver and lung cells, and MN assay of bone marrow and spleen cells. In addition, to identify agents that can potentially influence the results, concentrations of several heavy metals were analyzed in livers and in soil, and the total concentration of hydrocarbons in the soil was determined. Rodents exposed to coal were captured at two different sites, Butiá and Candiota, in RS. Reference animals were obtained from Pelotas, where there is no coal mining. This report provides chemical and biological data from coal regions, indicating the possible association between Zn, Ni, Pb and hydrocarbons in the induction of DNA damage (e.g. single strand-breaks and alkali-labile sites) determined by the alkaline SCG assay in cells from Ctenomys torquatus. The results of the present SCG study indicate that coal and by-products not only induce DNA damage in blood cells, but also in other tissue cells, mainly liver, kidney and lung. Neither the MN assay nor histopathological observations showed significant differences; these analyses may be useful under circumstances where genotoxicity is higher. In conclusion we believe that the in vivo genotoxicity of coal can be biomonitored by the SCG assay, and our studies suggest that wild rodents, such as C. torquatus are useful for monitoring genotoxic damage by both methods, the SCG assay and the MN test.

Essential elements and priority contaminants in liver, kidney, muscle and blubber of harp seal beaters

Concentrations of 22 elements were determined in blubber, liver, kidney and muscle of five male and five female, 8-month-old harp seals (Phoca groenlandica) by ICP-MS. Young harp seals are hunted during the spring and fall and represent an important traditional dietary item for some northern fishing communities. Interest in the commercial use of seal meat products and the limited data on the level of contaminants in tissues of harp seal beaters motivated our investigation. For most elements, concentrations in liver or kidney were greater than those in muscle. Blubber concentrations were generally lowest, but concentrations of Li, As, Sr, Ba and Pb were highest in blubber. Largest concentration factors [(tissue)/(water) > 10,000] were seen for P, Fe, Zn, Cu, Cd, Se, Mn, Ag, Pb and Co, a list that includes essential elements such as Fe and Zn, as well as several important contaminants such as Cd and Pb. Differences in concentration between male and female seals were only seen in eight of 88 element/tissue comparisons. Any effects of environmental exposure due to location or dietary intake are difficult to detect. Principle component analysis shows an association of Ca with Sr and P with S; and also a distinct grouping of the elements V, Mo, Cu and Ag.