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Persistent organic pollutants in liver of Brazilian sharpnose shark (Rhizoprionodon lalandii) from southeastern coast of Brazil Texto completo
2014
Cascaes, M.J. | Oliveira, R.T. | Ubarana, M.M. | Sato, R.M. | Baldassin, P. | Colabuono, F.I. | Leonel, J. | Taniguchi, S. | Weber, R.R.
In the present study, persistent organic pollutants (POPs) were determined in 14 livers from specimens of the Brazilian sharpnose shark (Rhizoprionodon lalandii), which is an important economic resource for small-scale fisheries on the southeastern coast of Brazil. The following concentrations (lipid weight) of POPs were found: ∑PCBs: 1019±267ngg−1; ∑DDTs: 111±40ngg−1 and ∑PBDEs: 10.4±4.78. PCB 153 made the greatest contribution to ∑PCB (21.4%), followed by PCB 138 (14.6%) and PCB 180 (9.94%). Among chlorinated pesticides, only the p,p′-DDE and p,p′-DDD isomers had concentrations above the detection limit. Moreover, levels above the detection limit were found only for PBDE congeners 47 and 100 (BDEs 47>99). On average, BDE 47 accounted for 88% of the total PBDE load. The feeding habits of the Brazilian sharpnose shark close to the Brazilian coastline are likely the most important difference regarding the accumulation of POPs in comparison to oceanic species that feed in deeper waters. Thus, this species may be used to evaluate the pollution of coastal areas as well as human exposure to contaminants, as the Brazilian sharpnose shark is a frequently used for human consumption. Further studies in other areas of Brazil and involving other species are needed to clarify the mechanisms and potential impact of POPs, which can affect the biology of different organisms and cause population declines.
Mostrar más [+] Menos [-]Distribution of resting cysts of the potentially toxic dinoflagellate Alexandrium pseudogonyaulax in recently-deposited sediment within Bizerte Lagoon (Mediterranean coast, Tunisia) Texto completo
2014
Triki, Habiba Zmerli | Daly-Yahia, Ons Kéfi | Malouche, Dhafer | Komiha, Yosr | Deidun, Alan | Brahim, Mouldi | laabir, Mohamed
This study investigated the spatial distribution of Alexandrium pseudogonyaulax resting cysts in recently-deposited sediment of Bizerte lagoon (South-Western Mediterranean, Tunisia). This lagoon is the subject of many anthropogenic impacts, such as holding important fishing and aquaculture activities. A. pseudogonyaulax has been shown to produce Goniodomin A, which is a biologically-active compound. We showed that this dinoflagellate produces two types of resting cysts, which could be distinguished by the presence or the absence of a paratabulate wall. The average cyst density across the whole lagoon was rather high, reaching 639cystsg−1 of dry sediment (DS). Cyst densities varied widely among the sampled stations, with the highest density of 1685cystg−1DS being recorded at station 51 near a mussel farm. With respect to sediment characteristics, the highest cyst densities were found within silty sediments with high water content values. The distribution of A. pseudongoyaulax cysts in Bizerte lagoon appears to be related to hydrodynamic factors.
Mostrar más [+] Menos [-]Organohalogen contaminants and trace metals in North-East Atlantic porbeagle shark (Lamna nasus) Texto completo
2014
Bendall, Victoria A. | Barber, Jonathan L. | Papachlimitzou, Alexandra | Bolam, Thi | Warford, Lee | Hetherington, Stuart J. | Silva, Joana F. | McCully, Sophy R. | Losada, Sara | Maes, Thomas | Ellis, Jim | Law, Robin J.
The North-East Atlantic porbeagle (Lamna nasus) population has declined dramatically over the last few decades and is currently classified as ‘Critically Endangered’. As long-lived, apex predators, they may be vulnerable to bioaccumulation of contaminants. In this study organohalogen compounds and trace elements were analysed in 12 specimens caught as incidental bycatch in commercial gillnet fisheries in the Celtic Sea in 2011. Levels of organohalogen contaminants were low or undetectable (summed CB and BDE concentrations 0.04–0.85mgkg−1wet weight). A notably high Cd concentration (7.2mgkg−1wet weight) was observed in one mature male, whereas the range observed in the other samples was much lower (0.04–0.26mgkg−1wet weight). Hg and Pb concentrations were detected only in single animals, at 0.34 and 0.08mgkg−1wet weight, respectively. These contaminant levels were low in comparison to other published studies for shark species.
Mostrar más [+] Menos [-]Cryptosporidium and Giardia in tropical recreational marine waters contaminated with domestic sewage: Estimation of bathing-associated disease risks Texto completo
2014
Betancourt, Walter Q. | Duarte, Diana C. | Vásquez, Rosa C. | Gurian, Patrick L.
Sewage is a major contributor to pollution problems involving human pathogens in tropical coastal areas. This study investigated the occurrence of intestinal protozoan parasites (Giardia and Cryptosporidium) in tropical recreational marine waters contaminated with sewage. The potential risks of Cryptosporidium and Giardia infection from recreational water exposure were estimated from the levels of viable (oo) cysts (DIC+, DAPI+, PI−) found in near-shore swimming areas using an exponential dose response model. A Monte Carlo uncertainty analysis was performed in order to determine the probability distribution of risks. Microbial indicators of recreational water quality (enterococci, Clostridium perfringens) and genetic markers of sewage pollution (human-specific Bacteroidales marker [HF183] and Clostridium coccoides) were simultaneously evaluated in order to estimate the extent of water quality deterioration associated with human wastes. The study revealed the potential risk of parasite infections via primary contact with tropical marine waters contaminated with sewage; higher risk estimates for Giardia than for Cryptosporidium were found. Mean risks estimated by Monte Carlo were below the U.S. EPA upper bound on recreational risk of 0.036 for cryptosporidiosis and giardiasis for both children and adults. However, 95th percentile estimates for giardiasis for children exceeded the 0.036 level. Environmental surveillance of microbial pathogens is crucial in order to control and eradicate the effects that increasing anthropogenic impacts have on marine ecosystems and human health.
Mostrar más [+] Menos [-]Water solubility of metals in coarse PM and PM2.5 in typical urban environment in Hong Kong Texto completo
2014
Jiang, Sabrina Y.N. | Yang, Fenhuan | Chan, Ka Lok | Ning, Zhi
An investigation of abundance and solubility of metals in size–segregated particulate matter (PM) was conducted at a typical urban site during the winter between late 2011 and early 2012 in Kowloon Tong, Hong Kong. The samples were extracted by both strong acid and water, and fourteen elements including Al, Ca, Cd, Cr, Co, Cu, Fe, Pb, Mg, Mn, Mo, Ni, V, and Zn were analyzed using Inductively Coupled Plasma Optical Emission Spectrometry (ICP–OES) and Inductively Coupled Plasma Mass Spectrometry (ICP–MS). The metals in PM showed distinctly different profiles of their distribution between coarse particles (2.5μm<dp<10μm) and PM2.5 (dp<2.5μm). The upper continental crustal enrichment factors (CEFs) of the measured metals for two particle size fractions showed that CEFs for nine of fourteen metals in PM2.5 were higher than 10 while Cd, Pb, Zn, Mn and Cu were far above 100; whereas for coarse particles, the CEFs of most elements were lower than 10, except for Cd being higher than 100. Water and acid extractable fractions of coarse PM and PM2.5 were analyzed and compared to investigate the transition metals solubility. The water extractable fraction was found to be present mainly in the fine particles, whereas more of the coarse fraction mass remained as insoluble fraction. The results from this study demonstrated large variation of water solubility of metals in urban aerosols in different size fractions and highlighted solubility as an important metric for considering the relation between metals and adverse health effects in epidemiological and toxicological studies.
Mostrar más [+] Menos [-]Airborne molds and mycotoxins in Serpula lacrymans–damaged homes Texto completo
2014
Pottier, Didier | André, Véronique | Rioult, Jean–Philippe | Bourreau, Alain | Duhamel, Chantal | Bouchart, Valerie Kientz | Richard, Estelle | Guibert, Mathieu | Verite, Philippe | Garon, David
For some years, the degradation of homes by the dry rot fungus Serpula lacrymans increased. This study described, for the first time, the fungal contamination in homes located in Low–Normandy (France) and damaged by Serpula lacrymans. Wood–decaying fungi, airborne molds, fungal species growing on building materials were investigated by cultural and molecular methods. Mycotoxins in the air were quantified by HPLC–MS/MS and the mutagenicity of fungal aerosols was also evaluated using the Ames test. The results showed that Serpula lacrymans was detected in the air for one third of homes with sometimes the co–occurrence of other ligninolytic basidiomycetes species like Donkioporia expansa. Various molds in the air and on materials (117 and 103 species, respectively) were also identified indicating the complexity of indoor mycoflora. Certain recurrent species like Aspergillus versicolor and Penicillium fellutanum were observed both on building materials and in the air. The presence of cellulolytic molds in fungal aerosols and on building materials could be used as an indicator of home degradation. Airborne culturable fungal levels were measured up to 5.8x105 Colony Forming Units (CFU) per cubic meter of the air (CFU/m3) depending on the home. Fungal concentrations also depended on the type of collector (filter or liquid) and were significantly correlated with the median of particles between 2–15μm in size. Two mycotoxins (alternariol and/or ochratoxin A) were observed in 4 homes but no mutagenic activity was found.
Mostrar más [+] Menos [-]Sulfur dioxide exposure and environmental justice: a multi–scale and source–specific perspective Texto completo
2014
Zou, Bin | Peng, Fen | Wan, Neng | Wilson, JGaines | Xiong, Ying
Recent studies examining racial and ethnic inequities in exposure to urban air pollution have led to advances in understanding the nature and extent of overall concentration exposures by pollutant, demarcated by disadvantaged groups. However, the stability of inequities at various spatial units and the exposure by air pollution sources are often neglected. In this case study from the Dallas–Fort Worth (Texas, USA) area, we used Geographic Information Systems (GIS) and an air dispersion model to estimate environmental justice impacts at different spatial scales (i.e., zip code, census tract, block group) and by source (i.e., industrial pollution sources, vehicle pollution sources, industry and vehicle pollution sources combined). Using whites as a reference, blacks and other races were more likely to be exposed to higher sulfur dioxide (SO2) concentrations although the Odds Ratio (OR) varied substantially by pollution source type [e.g., industrial pollution source based: (OR=1.80; 95% CI (Confidence Interval): 1.79–1.80) vs. vehicle pollution source based: (OR=2.70; 95% CI: 2.68–2.71)] and varied less between spatial scales [for vehicle pollution sources, (OR=2.70; 95% CI: 2.68–2.71) at the census tract level but was (OR=2.54; 95% CI: 2.53–2.55) at the block group scale]. Similar to the pattern of racial inequities, people with less education (i.e., less than 12 years of education) and low income (i.e., per capital income below $20 000) were more likely to be exposed to higher SO2 concentrations, and those ORs also varied greatly with the pollution sources and slightly with spatial scales. It is concluded that the type of pollution source plays an important role in SO2 pollution exposure inequity assessment, while spatial scale variations have limited influence. Future studies should incorporate source–specific exposure assessments when conducting studies on environmental justice.
Mostrar más [+] Menos [-]Spatiotemporal variability of hypoxia and eutrophication in Manila Bay, Philippines during the northeast and southwest monsoons Texto completo
2014
Sotto, Lara Patricia A. | Jacinto, Gil S. | Villanoy, Cesar L.
Hypoxia in Manila Bay, Philippines was previously reported during the northeast monsoon (dry season) in February 2010. In this study, four more field surveys of the same 31 stations were conducted in July 2010, August 2011 and 2012 (wet season, southwest monsoon), and February 2011 (dry season, northeast monsoon). During the wet season, bottom hypoxia spread northward towards the coast with dissolved oxygen (DO) ranging from 0.12 to 9.22mg/L and the bay-wide average reaching 2.10mg/L. Nutrient levels were elevated, especially near the bottom where dissolved inorganic nitrogen reached 22.3μM (July 2010) and phosphorus reached 5.61μM (August 2011). High nutrient concentrations often coincided with low near-bottom DO content. Our work builds on the preliminary assessment of hypoxia in Manila Bay, the importance of repeated temporal studies, and shows hypoxia to prevail significantly during the southwest monsoon (wet season) when increased freshwater discharge caused strong water column stratification.
Mostrar más [+] Menos [-]Assessment of TBT and organic booster biocide contamination in seawater from coastal areas of South Korea Texto completo
2014
Kim, Nam Sook | Shim, Won Joon | Yim, Un Hyuk | Hong, Sang Hee | Ha, Sung Yong | Han, Gi Myung | Shin, Kyung-Hoon
Seawater samples from major enclosed bays, fishing ports, and harbors of Korea were analyzed to determine levels of tributyltin (TBT) and booster biocides, which are antifouling agents used as alternatives to TBT. TBT levels were in the range of not detected (nd) to 23.9ng Sn/L. Diuron and Irgarol 1051, at concentration ranges of 35–1360ng/L and nd to 14ng/L, respectively, were the most common alternative biocides present in seawater, with the highest concentrations detected in fishing ports. Hot spots were identified where TBT levels exceeded environmental quality targets even 6years after a total ban on its use in Korea. Diuron exceeded the UK environmental quality standard (EQS) value in 73% of the fishing port samples, 64% of the major bays, and 42% of the harbors. Irgarol 1051 levels were marginally below the Dutch and UK EQS values at all sites.
Mostrar más [+] Menos [-]Maternal-to-fetal transfer and concentration profiles of PCB congeners for Steller sea lions (Eumetopias jubatus) from Hokkaido, Japan Texto completo
2014
Kubo, Keiko | Yamaguchi, Katsuyuki | Ishinazaka, Tsuyoshi | Yamada, Wakana | Hattori, Kaoru | Tanaka, Shunitz
The concentrations of PCB congeners in the blubber and liver of mother Steller sea lions (Eumetopias jubatus; SSLs) and their fetuses from the coast of Hokkaido, Japan in 2008, 2010 and 2012 were analyzed by HRGC–HRMS, in order to elucidate PCB congener profiles and maternal-to-fetal transfer of PCBs in SSLs. ΣPCBs in the fetuses were 1400±660 (the mean±SD) ng/g-fat in the blubber and 570±320ng/g-fat in the liver, respectively. There was a concern that SSLs had been contaminated by PCBs during the fetal period. The concentrations of the major congeners in the blubber and liver were a correlation between the fetus and mother (blubber: r=0.9934, liver: r=0.9160; P≦0.05). The results indicated that PCBs in the fetuses came from the mothers. #177 and #199 showed no correlations between the fetus and the mother in the blubber and liver. This indicated a selective capture by some natural protector such as the placenta.
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