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Polybrominated diphenyl ethers and decabromodiphenylethane in sediments from twelve lakes in China
2012
Wu, Fengchang | Guo, Jianyang | Chang, Hong | Liao, Haiqing | Zhao, Xiaoli | Mai, Bixian | Xing, Baoshan
Sediment cores from 12 Chinese lakes were analyzed to investigate the historical inputs of polybrominated diphenyl ethers (PBDEs) and decabromodiphenylethane (DBDPE) during the past few decades. Concentrations of ΣPBDE₁ (sum of tri- to hepta-BDEs), ΣPBDE₂ (sum of nona- to deca-BDEs) and DBDPE in the surface sediments were 0.02–0.29 ng g⁻¹, 0.46–46.6 ng g⁻¹ and 1.02–3.64 ng g⁻¹, respectively. The temporal trends of PBDEs and DBDPE followed a general increase from the bottom to the surface. The calculated fluxes for ΣPBDE₁, ΣPBDE₂ and DBDPE were 0.001–0.09, 0.03–4.24, and 0.05–0.31 ng cm⁻² yr⁻¹, and the inventories were 0.09–7.86, 0.91–461, and 3.83–24.6 ng cm⁻², respectively. The urbanization and industrialization are highly related to the contamination of PBDEs and DBDPE in sediments. The DBDPE input in recent years was still lower than ΣPBDE₂ but the temporal trends indicated that the contamination would increase with the increasing usage of DBDPE in the future.
اظهر المزيد [+] اقل [-]Ozone weekend effect in Santiago, Chile
2012
Seguel, Rodrigo J. | Morales S., Raúl G.E. | Leiva G., Manuel A.
The study examined weekday–weekend differences in ozone, NOₓ (NO and NO₂) and VOC concentrations in Santiago, Chile, from 1999 to 2007. The results provide evidence for the occurrence of an atmospheric phenomenon that produces higher ozone concentrations during weekends despite lower concentrations of ozone precursors. This phenomenon is known as the weekend effect (WE). The overall ozone decrease since the spring of 2004 was a consequence of the implementation of several urban pollution control measures. Although these measures caused a decline in the number of days that exceed the national standard from two-thirds to one-third of summer days, the WE, which became statistically significant beginning in September 2004, could not be eliminated. Furthermore, VOC/NOₓ ratios decreased during the same period (2004), especially in the most industrialized area of Santiago. Similarly, under these regimes, the VOC/NOₓ ratios were higher on Sundays than on weekdays and caused higher ozone concentrations on Sundays.
اظهر المزيد [+] اقل [-]Natural and anthropogenically-produced brominated compounds in endemic dolphins from Western South Atlantic: Another risk to a vulnerable species
2012
Alonso, Mariana B. | Eljarrat, Ethel | Gorga, Marina | Secchi, Eduardo R. | Bassoi, Manuela | Barbosa, Lupércio | Bertozzi, Carolina P. | Marigo, Juliana | Cremer, Marta | Domit, Camila | Azevedo, Alexandre F. | Dorneles, Paulo R. | Torres, João Paulo M. | Lailson-Brito, José | Malm, Olaf | Barceló, Damià
Liver samples from 53 Franciscana dolphins along the Brazilian coast were analyzed for organobrominated compounds. Target substances included the following anthropogenic pollutants: polybrominated diphenyl ethers (PBDEs), polybrominated biphenyls (PBBs), pentabromoethylbenzene (PBEB), hexabromobenzene (HBB), decabromodiphenylethane (DBDPE), as well as the naturally-generated methoxylated-PBDEs (MeO-PBDEs). PBDE concentrations ranged from 6 to 1797 ng/g lw (mean 166 ± 298 ng/g lw) and were similar to those observed in cetaceans from Northern Hemisphere. PBBs were found in all sampling locations (<LOQ to 57 ng/g lw). DBDPE was detected in 42% of the dolphins from the most industrialized Brazilian state and the concentrations ranging from <LOQ to 352 ng/g lw. Franciscana dolphins from the tropical Brazilian shore presented the highest MeO-PBDE concentrations ever reported for coastal cetaceans (up to 14 μg/g lw). Eight MeO-PBDE congeners were detected and the present investigation constituted the first record of occurrence of six of them in marine mammal livers.
اظهر المزيد [+] اقل [-]Hexabromocyclododecane in terrestrial passerine birds from e-waste, urban and rural locations in the Pearl River Delta, South China: Levels, biomagnification, diastereoisomer- and enantiomer-specific accumulation
2012
Sun, Yu-xin | Luo, Xiao-jun | Mo, Ling | He, Ming-jing | Zhang, Qiang | Chen, She-jun | Zou, Fa-sheng | Mai, Bi-xian
Diastereoisomers and enantiomers of hexabromocyclododecane (HBCD) were determined in muscle and stomach contents of three terrestrial passerine birds from e-waste, urban and rural locations in South China. The highest HBCD concentration was found at the urban site, followed by the e-waste site, suggesting that HBCD was linked to urbanization and industrialization, as well as e-waste recycling activities. Trophic magnification for α-HBCD was observed in the terrestrial food chain. Diastereisomeric pattern in birds showed the predominance of α-isomer, with a minor contribution of γ-isomer. The enantiomeric analysis revealed a preferential enrichment of (−)-α-HBCD and (+)-γ-HBCD. The similarity in enantiomeric fractions of HBCD isomers between muscle and stomach contents of birds suggested that dietary uptake may be responsible for the observed nonracemic distribution of HBCD isomers in the studied birds although in vivo enantioselective biotic processes cannot be ruled out.
اظهر المزيد [+] اقل [-]Investigating a high ozone episode in a rural mountain site
2012
Monteiro, A. | Strunk, A. | Carvalho, A. | Tchepel, O. | Miranda, A.I. | Borrego, C. | Saavedra, S. | Fernandez, Aurelio Rodriguez | Souto, J. | Casares, J. | Friese, E. | Elbern, H.
A very high ozone episode with observed hourly values above 350 μg m⁻³ occurred in July 2005 at the Lamas d’Olo air quality monitoring station, located in a mountainous area in the north of Portugal. Aiming to identify the origin and formation of this ozone-rich episode, a statistical analysis and a modelling approach were applied. A cross-spectrum analysis in the frequency domain and a synoptic analysis of the meteorological and air quality time series were performed. In order to go further in this analysis, a numerical modelling approach was applied. The results indicate that the transport of ozone and its precursors is the main responsible for the high ozone concentrations. Together with the local mountain breeze and subsidence conditions, the sea-breeze circulation transporting pollutants from the coastal urban and industrialized areas that reach the site during late afternoon turn out to be the driving forces for the ozone peaks.
اظهر المزيد [+] اقل [-]Measurement of persistent organic pollutants (POPs) in plastic resin pellets from remote islands: Toward establishment of background concentrations for International Pellet Watch
2012
Heskett, Marvin | Takada, Hideshige | Yamashita, Rei | Yuyama, Masaki | Ito, Maki | Geok, Yeo Bee | Ogata, Yuko | Kwan, Charita | Heckhausen, Angelika | Taylor, Heidi | Powell, Taj | Morishige, Carey | Young, Doug | Patterson, Hugh | Robertson, Bryson | Bailey, Elizabeth | Mermoz, Jorge
Plastic resin pellets collected from remote islands in the Pacific, Atlantic, and Indian Oceans and the Caribbean Sea were analyzed for polychlorinated biphenyls (PCBs), dichloro-diphenyltrichloroethane and its degradation products (DDTs), and hexachlorocyclohexanes (HCHs). Concentrations of PCBs (sum of 13 congeners) in the pellets were 0.1–9.9ng/g-pellet. These were 1–3 orders of magnitude smaller than those observed in pellets from industrialized coastal shores. Concentrations of DDTs in the pellets were 0.8–4.1ng/g-pellet. HCH concentrations were 0.6–1.7ng/g-pellet, except for 19.3ng/g-pellet on St. Helena, where current use of lindane is likely influence. This study provides background levels of POPs (PCBs<10ng/g-pellet, DDTs<4ng/g-pellet, HCHs<2ng/g-pellet) for International Pellet Watch. Sporadic large concentrations of POPs were found in some pellet samples from remote islands and should be considered in future assessments of pollutants on plastic debris.
اظهر المزيد [+] اقل [-]Petroleum hydrocarbon contamination in Nelson Lagoon, Alaska, sampling three different matrices
2012
Lance, Ellen W. | Matz, Angela C. | Reeves, Mari K. | Verbrugge, Lori A.
Polycyclic aromatic hydrocarbon (PAH) levels were measured in sediments, bivalves and semi-permeable membrane devices (SPMDs) in the relatively pristine marine environment of Nelson Lagoon, Alaska. Most PAH levels in Nelson Lagoon were low, and similar to global background concentrations. Sampling media type can significantly influence conclusions of PAH contamination in the environment. Concentration of a broad size range of PAHs was observed in the tissues of blue mussels (Mytilus edulis). SPMDs collected some two- to three-ring PAHs from the dissolved water phase, while sediments collected five- to six-ring PAHs that were likely adsorbed onto particulate matter. Benzo(a)pyrene, a potent carcinogen, was found in mussels at levels similar to more industrialized harbors in Alaska.
اظهر المزيد [+] اقل [-]Water characterization in three industrialized harbours (Vigo, Bilbao and Pasajes) in North Coast of Spain
2012
Durán, Iria | Nieto, Oscar
Total dissolved Cu, Zn, Pb and Cd concentrations, speciation, fluorescence of organic matter and toxicity for sea urchin development have been studied during three years in water samples of three of the most industrialized harbours in North Coast of Spain: Vigo, Bilbao and Pasajes. Total metal concentrations were below 0.4nM for Cd and generally below 2nM for Pb. Zn and Cu levels were higher (2.8–9nM Cu and 15–234nM Zn) and denoted an anthropogenic enrichment. Ligand concentrations were usually between 50 and 200nM for Cu and between 6 and 80 for Pb and Zn. Organic matter and speciation analysis yielded complementary information to characterize the samples, but no correlation was present between the parameters calculated by both methods. Samples were tested for toxicity with sea urchin embryo bioassay and three samples were toxic but the toxicity could not be explained with the metal levels here measured.
اظهر المزيد [+] اقل [-]Sedimentary records of metal contamination and eutrophication in Jinhae-Masan Bay, Korea
2012
Lim, Dhong-il | Jung, Hoi Soo | Kim, Kyung Tae | Shin, Hyeon Ho | Jung, Seung Won
Historical environmental pollution in a semi-enclosed coastal bay was investigated using high-resolution sedimentary records for Cₒᵣg, Nₜₒₜ, CaCO₃, δ¹³C, and δ¹⁵N signatures, and trace metals. A temporal increase in organic matter might have been attributable to enhanced primary marine productivity, presumably caused by increased anthropogenic nutrient inputs in the semi-enclosed, eutrophic system. Metal accumulation occurred in three stages: a preindustrial stage before the 1930s with natural concentrations of metals, an industrialization stage (1940s–1970s) with the highest concentrations, and a postindustrial stage (post 1970s) with stable or decreasing concentrations. However, Hg exhibited a different accumulation history, with concentrations increasing in the early 1900s and accelerating after the 1920s, probably in response to coal burning.
اظهر المزيد [+] اقل [-]Historical changes in trace metals and hydrocarbons in nearshore sediments, Alaskan Beaufort Sea, prior and subsequent to petroleum-related industrial development: Part I. Trace metals
2012
Naidu, A Sathy | Blanchard, Arny L. | Misra, Debasmita | Trefry, John H. | Dasher, Douglas H. | Kelley, John J. | Venkatesan, M Indira
Concentrations of Fe, As, Ba, Cd, Cu, Cr, Pb, Mn, Ni, Sn, V and Zn in mud (<63μm size), and total and methyl Hg in gross sediment are reported for Arctic Alaska nearshore. Multivariate-PCA analysis discriminated seven station clusters defined by differences in metal concentrations, attributed to regional variations in granulometry and, as in Elson Lagoon, to focused atmospheric fluxes of contaminants from Eurasia. In Colville Delta-Prudhoe Bay, V increase was noted in 1985 and 1997 compared to 1977, and Ba increase from 1985 to 1997. Presumably the source of increased V is the local gas flaring plant, and the elevated Ba is due to barite accumulation from oil drilling effluents. In Prudhoe Bay, concentration spikes of metals in ∼1988 presumably reflect enhanced metals deposition following maximum oil drilling in 1980s. In summary, the Alaskan Arctic nearshore has remained generally free of metal contamination despite petroleum-related activities in past 40years.
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