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801.
This article summarizes results from raptor monitoring and contamination studies in Norway of the golden eagle, gyrfalcon, white-tailed sea eagle, osprey, peregrine, and merlin. Golden eagle and gyrfalcon populations have been monitored since 1990 as part of the "Monitoring Programme for Terrestrial Ecosystems" (TOV). No long-term trend in the population size or productivity of golden eagle has been shown in any of the 5 study areas. The reproductive output of gyrfalcon is monitored in 3 areas. It is positively correlated with the populations of its main prey species, the rock ptarmigan and the willow ptarmigan. The white-tailed sea eagle population has been monitored since 1974 by the Norwegian Ornithological Society, and the population is increasing. The levels of pesticides and polychlorinated biphenyls are low in the eggs of both the golden eagle and the gyrfalcon, but elevated levels and effects on reproduction have been indicated for a coastal subpopulation of golden eagle. The pollutant levels in white-tailed sea eagle are lower than in the Baltic population of sea eagles, and shell thinning was never severe overall, but individual eggs have contained pollutant concentrations above critical levels. The levels of pollutants in the bird-eating falcons, peregrine, and merlin were higher than in other species. New emerging pollutants, like brominated diphenylethers and perfluorinated organic compounds, could be detected in all species. By incorporating available published and unpublished data, we were able to produce time trends for pollutants and shell thickness over 4 decades.  相似文献   
802.
Arsenic oxidation (As(III) to As(V)) and As(V) removal from water were assessed by using TiO2 immobilized in PET (polyethylene terephthalate) bottles in the presence of natural sunlight and iron salts. The effect of many parameters was sequentially studied: TiO2 concentration of the coating solution, Fe(II) concentration, pH, solar irradiation time; dissolved organic carbon concentration. The final conditions (TiO2 concentration of the coating solution: 10%; Fe(II): 7.0 mg l−1; solar exposure time: 120 min) were applied to natural water samples spiked with 500 μg l−1 As(III) in order to verify the influence of natural water matrix. After treatment, As(III) and total As concentrations were lower than the limit of quantitation (2 μg l−1) of the voltammetric method used, showing a removal over 99%, and giving evidence that As(III) was effectively oxidized to As(V). The results obtained demonstrated that TiO2 can be easily immobilized on a PET surface in order to perform As(III) oxidation in water and that this TiO2 immobilization, combined with coprecipitation of arsenic on Fe(III) hydroxides(oxides) could be an efficient way for inorganic arsenic removal from groundwaters.  相似文献   
803.
Concentrations of polychlorinated dibenzo-p-dioxins (PCDD), polychlorinated dibenzofurans (PCDF) and polychlorinated biphenyls (PCB) in Baltic Sea fish like herring (Clupea harengus membras), sprat (Sprattus sprattus balticus), perch (Perca fluviatilis), pikeperch (Sander lucioperca) and flounder (Platichthys flesus trachurus) collected from four areas of the Estonian coastal waters are reported. All samples are studied for their relationship between the length (cm) and wet weight (g); length (cm) and age (years); lipid content and dry matter. The level of PCDD/F and PCB concentrations in younger 1-5 years old Baltic herring and sprat collected in 2002-2005 from the eastern and central parts of the Gulf of Finland, Gulf of Riga and Open Baltic Sea (Central Baltic) is related to the fish age and compared with those found in the 1990s. In addition, PCDD/F and PCB concentrations of different age groups herring, sprat, perch, pikeperch and flounder collected in 2003-2004 from the Lake Peipsi, Gulf of Finland, Gulf of Riga and Open Baltic Sea are related also to their age. Consequently, it was manifested that in older Baltic fish the concentrations of PCDD/F and PCB were higher than in the younger age groups. By the help of principle component analysis (PCA) the effect of gender on the concentrations of PCDD/F for the juvenile Baltic herring and sprat collected in 2004-2005 is investigated for the first time. It was summarized that the biological factor age plays a large role for the contamination of the fish with important toxic organohalogenated compounds such as PCDD/F.  相似文献   
804.
The purpose of this study was to test the efficiency of passive solid samplers, polyoxymethylene (POM) strips and polydimethylsiloxane (PDMS) silicon tubing, to predict the bioavailability of native PAHs in contaminated sediments. Results were compared with worm bioaccumulation data and solid/liquid extraction using the surfactant Brij((R)) 700 (B700). The two passive samplers were found to act differently. The PDMS sampler overestimated the availability of PAHs in all studied sediments. The POM method provided results in accordance with those obtained with the B700 extraction. However, POM and B700 methods underestimated PAH availability in low contaminated sediments where biological factors (digestible organic matter) become important. Bioavailability of total PAHs was correctly predicted by POM and B700 in highly contaminated aluminum smelter sediments. A closer examination of individual PAH results indicated that both techniques overestimated the availability of large molecules with logK(ow)>6 suggesting a biological mechanism limiting uptake of larger PAHs which seems to be related to the molecular size of compounds.  相似文献   
805.
An optimized microwave assisted extraction method for determination of trinitrotoluene (TNT) and related compounds in soil is presented. The new enhanced method exhibits improved extraction recovery and precision as well as sample handling time. For the separation and detection gas chromatography coupled to a thermoionic probe was used achieving TNT and dinitrotoluene detection limits per injection at the femtogram level. The generated extraction recovery and precision data are given for spiked and certified soil. Determined TNT and related compounds residues in soil collected from different parts of the world are presented.  相似文献   
806.
Hydroxylated polybrominated diphenyl ethers (OH-PBDEs) and methoxylated polybrominated diphenyl ethers (MeO-PBDEs) are present in the ecosystem of the Baltic Sea. OH-PBDEs are known to be both natural products from marine environments and metabolites of the anthropogenic polybrominated diphenyl ethers (PBDEs), whereas, MeO-PBDEs appear to be solely natural in origin. Polybrominated dibenzo-p-dioxins (PBDDs) are by-products formed in connection with the combustion of brominated flame retardants (BFRs), but are also indicated as natural products in a red alga (Ceramium tenuicorne) and blue mussels living in the Baltic Sea. The aims of the present investigation were to quantify the OH-PBDEs and MeO-PBDEs present in C. tenuicorne; to verify the identities of PBDDs detected previously in this species of red alga and to investigate whether cyanobacteria living in this same region of the Baltic Sea contain OH-PBDEs, MeO-PBDEs and/or PBDDs. The red alga was confirmed to contain tribromodibenzo-p-dioxins (triBDDs), by accurate mass determination and additional PBDD congeners were also detected in this sample. This is the first time that PBDDs have been identified in a red alga. The SigmaOH-PBDEs and SigmaMeO-PBDEs concentrations, present in C. tenuicorne were 150 and 4.6 ng g(-1) dry weight, respectively. In the cyanobacteria 6 OH-PBDEs, 6 MeO-PBDEs and 4 PBDDs were detected by mass spectrometry (electron capture negative ionization (ECNI)). The PBDDs and OH-PBDEs and MeO-PBDEs detected in the red alga and cyanobacteria are most likely of natural origin.  相似文献   
807.
Persistent organic pollutants (POPs) are chemicals that accumulate in the food chain and are toxic to humans and wildlife. The fourth World Health Organization (WHO) survey on POP levels in human milk (2006-2009) aims to provide baseline and trend information on human exposure to POPs. So far Belgium participated in all three previous rounds (1988, 1992, 2001). Whereas the first three rounds focused on determination of dioxins and PCBs in pooled (mixed) samples, the fourth survey comprised the analyses of individual milk samples for nine "basic POPs" (chlorinated pesticides and indicator PCBs) and of pooled milk samples for "basic POPs", "advanced POPs" (dioxins and dioxin-like PCBs) and "optional POPs" (polybrominated diphenylethers [PBDEs], polybrominated dioxins and dibenzofurans [PBrDD/F], mixed halogenated dioxins and dibenzofurans [PXDD/F] and hexabromocyclododecane [HBCD]). For the Belgian participation human milk samples were collected during the summer of 2006 from 197 women between 18 and 30 years old distributed over all Belgian provinces. The individual samples were analyzed in a Belgian Laboratory for "basic" POPs. A pooled sample was made from 178 individual samples and analyzed by the WHO Reference Laboratory for the "basic, advanced and optional" POPs. The results indicate that most organochlorinated pesticides banned 25-30 years ago were below or around detection limits in Belgian human milk samples although DDE was still found at low levels in all samples. Over the last five years the levels of marker PCBs and PCDD/Fs in Belgian human milk decreased, respectively, by 58% and 39%. For some of the other emerging or older compounds recent international data are needed to allow comparison. This shows the importance of international studies as run by WHO.  相似文献   
808.
Developmental disorders of teeth are among the most sensitive targets of polychlorinated dibenzo-p-dioxin and -furan (PCDD/F) exposure. In rats, 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) reduces dose-dependently the size of molars, most severely the third lower molars. Dioxins also have effects on developing bone, including altered bone mineral density as well as reduced bending breaking force and stiffness. The aim of this study was to evaluate the use of the third lower molar and long bones as biomarkers of PCDD/F exposure in two wild vole species, the bank vole (Clethrionomys glareolus) and the field vole (Microtus agrestis) collected from a PCDD/F contaminated former sawmill area. Survey of soil and biota of the sawmill area indicated a PCDD/F contamination with a congener profile characteristic for the chlorophenol wood preservative Ky-5. The PCDD/F concentration in the bank vole was notably higher than in the field vole. The third molar of the bank vole was significantly smaller in dioxin-exposed animals compared to control group, while there was no difference between these two groups in the field vole. No significant alterations were observed in bone density and strength in either species except for reduced bending strength of the femur neck in bank vole males exposed to dioxins. Even though the bone changes are among the sensitive endpoints of dioxin-exposure, high variability due to age, size and gender limits their use as biomarkers of wildlife exposure. In conclusion, the size of molar teeth seems to be a sensitive and robust biomarker for PCDD/F exposure in wild bank vole populations and thus worth of further studies.  相似文献   
809.
Recent survey results for polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs, dioxins) in Baltic Sea sediments from Finland, Sweden and Denmark were merged with previously published Baltic Sea data. Regional distribution of concentration levels, differences in congener patterns, and temporal changes in sediment profiles were examined. One of the main objectives was to study if any major point sources for different PCDD/F congeners could be identified on a regional scale, based on sediment records. The survey confirmed the impact of chlorophenol production derived highly chlorinated PCDF-congeners on the total toxicity in sediments in the Gulf of Finland near the Kymijoki river estuary. Signatures of other point sources or combined point sources pertinent to specific industry branches or particular production processes (such as pulp bleaching, vinyl chloride production, thermal processes) may be discerned. However, the findings did not support any of the known point sources significantly influencing those congeners that are most abundant in Baltic herring and salmon. Instead, regional distributions in the Baltic Sea indicate that atmospheric deposition may act as a major source for those congeners and especially for 2,3,4,7,8-PeCDF. There were clear indications of declines in levels in sediment in some areas, but generally the levels of highly chlorinated PCDD/Fs on the northern coast of the Gulf of Finland were still high when compared with other areas of the Baltic Sea. Major areas with data gaps cover the south-eastern and eastern coastal regions of the Baltic Proper and the southern Gulf of Finland.  相似文献   
810.
Monitoring of immission of persistent organic pollutants in the industrialized area of Volta Redonda (V.R.) and in the National Park of Itatiaia (PNI) in southeast Brazil was performed using an endemic Bromeliad species as biomonitor and measuring total deposition rates on funnels covered with polyurethane foams. Samples were collected during 78 days in V.R. and 95 days in PNI in winter (dry season, June-August 2003) and during 114 days in both areas in summer (rainy season, December 2003-February 2004). The PCDD/PCDF deposition rates ranged from 0.10 to 1.9 pg WHO-TEQ/(m2 day) in winter and from 0.11 to 2.2 pg WHO-TEQ/(m2 day) in summer. Deposition rates found in V.R. in summer were four- to ninefold higher than those measured in PNI, while in winter deposition rates in both regions were in the same range. Deposition rates in V.R. in summer were about five fold lower than those measured in 1996. PCDD/PCDF levels in biomonitor samples were between 0.95 and 14.6 ng WHO-TEQ/kg d.m. in winter and between 2.2 and 5.2 ng WHO-TEQ/kg d.m. in summer. In winter, concentrations found in V.R. were up to 11 times higher than those found in PNI, while in summer the levels measured in both areas were comparable. The homologue and isomer profiles found in the deposition as well as in the biomonitor samples from V.R. indicate that steel production is the main source of contamination in the region, whereas in PNI, the long range transport of these pollutants is the predominant contamination pathway.  相似文献   
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