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1.
Used lead–acid battery (ULAB) recycling has caused numerous health and environmental issues in developing countries. Surface soil pollution from ULAB recycling activities has been linked with elevated levels of lead in human blood. We measured surface soil lead in and surrounding the ULAB recycling village of Hung Yen in northern Vietnam in 2011, 2013, and 2014. The data were analyzed statistically and discussed with respect to distance from the contamination source, year of measurement, contamination pathway, and countermeasures against the contamination. Transportation routes from the smelter or collection site displayed the greatest concentration of surface soil lead (median 6400–10,000 mg/kg). Surface soil lead decreased significantly with distance along the road from the ULAB recycling site, although such a decrease was not observed for rice fields, agricultural roads, or garden soil. Re-suspension and adherence by traffic were identified as key pollution pathways. Distance from the source, covering of the surface of roads, construction of walls, and position relative to the source were shown to be the most effective factors in the reduction of surface soil lead pollution. Application of a combination of these measures should result in improvement in the health of residents.  相似文献   
2.
We determined the residue levels and patterns of hydroxylated polybrominated diphenyl ethers (OH-PBDEs), and related compounds, such as PBDEs, methoxylated PBDEs (MeO-PBDEs), and bromophenols (BPhs) in the blood of eleven cetacean species stranded along the Japanese coasts. The dominant OH- and MeO-PBDE isomers found in all cetaceans were 6OH-BDE47 and 6MeO-BDE47. Additionally, 2,4,6-triBPh was dominant isomer in all cetaceans. In contrast, specific differences in the distribution of para- and meta- OH-PBDE isomers and some BPhs (potential PBDEs metabolites) were found among the cetaceans.Residue levels of ΣMeO-PBDEs and 6OH-BDE47 + 2′OH-BDE68, and 2,4,6-triBPh and 6OH-BDE47 + 2′OH-BDE68 showed a significant positive correlation. These results may suggest that the large percentages of OH-PBDEs, MeO-PBDEs and 2,4,6-triBPh might share common source (i.e. biosynthesis by marine organisms), or metabolic pathway in cetacean species. Significant correlations were found between the concentrations of BDE99 and 2,4,5-triBPh. This result suggested that 2,4,5-triBPh in cetaceans could be a metabolite of BDE99.  相似文献   
3.
Environmental Economics and Policy Studies - This study employs a data envelopment analysis (DEA) framework using long-term panel data of the physical stocks of buildings and infrastructure...  相似文献   
4.
Glycosylation of bisphenol A by freshwater microalgae   总被引:1,自引:0,他引:1  
The endocrine disruptor bisphenol A (BPA, 4,4'-isopropylidenediphenol) is used to manufacture polycarbonate plastic and epoxy resin linings of food and beverage cans, and the residues from these products are then sometimes discharged into rivers and lakes in waste leachates. However, the fate of BPA in the environment has not yet been thoroughly elucidated. Considering the effect of BPA on aquatic organisms, it is important that we estimate the concentration of BPA and its metabolites in the aquatic environment, but there are few data on the metabolites of BPA. Here, we focused on freshwater microalgae as organisms that contribute to the biodegradation or biotransformation of BPA in aquatic environments. When we added BPA to cultures of eight species of freshwater microalgae, a reduction in the concentration of BPA in the culture medium was observed in all cultures. BPA was metabolized to BPA glycosides by Pseudokirchneriella subcapitata, Scenedesmus acutus, Scenedesmus quadricauda, and Coelastrum reticulatum, and these metabolites were then released into the culture medium. The metabolite from P. subcapitata, S. acutus, and C. reticulatum was identified by FAB-MS and (1)H-NMR as bisphenol A-mono-O-beta-d-glucopyranoside (BPAGlc), and another metabolite, from S. quadricauda, was identified as bisphenol A-mono-O-beta-d-galactopyranoside (BPAGal). These results demonstrate that freshwater microalgae that inhabit universal environments can metabolize BPA to its glycosides. Because BPA glycosides accumulate in plants and algae, and may be digested to BPA by beta-glycosidase in animal intestines, more attention should be given to levels of BPA glycosides in the environment to estimate the ecological impact of discharged BPA.  相似文献   
5.
The biocatalytic potential of two novel Brazilian strains of Aspergillus niger and Rhodotorula glutinis, revealed enantioselective epoxide hydrolase activity in the asymmetrization of meso-epoxide and monosubstituted epoxides respectively. These two types of oxirane derivatives are not usually good substrates for biocatalytic enantioselective conversion.  相似文献   
6.
Polycarbonate (PC) pellets were subjected to dilute aqueous ammonia solution under hydrothermal conditions in a semi-batch reactor at temperatures ranging from 433 to 463 K and at a pressure of 10 MPa. The PC pellets were almost completely converted to bisphenol A (BPA). During an initial certain period, referred to as an induction time, neither BPA nor total organic carbon in solution were detected, and the BPA yield increased with time. The monomer yield was well represented by a surface reaction model, two-thirds-order reaction with respect to the mass of unreacted PC. The overall rate constant of the reaction in 0.6 mol/kg aqueous ammonia solution at 433 K was about 15 times greater than that in 0.6 mol/kg NaOH solution. The rate constant at 433 K was proportional to the ammonia or NaOH concentration. There was a correlation between the induction time and temperature, as well as the ammonia or NaOH concentration. By carrying out the reaction in aqueous mixtures of (NH4)2SO4 and NaOH at various concentrations of NaOH, ammonia was confirmed not to function as an alkaline reagent, but as a nucleophile reagent.  相似文献   
7.
8.
Longitudinal capture-mark-recapture data were used to estimate abundance and survival rates for green turtles (Chelonia mydas) in San Diego Bay, California, USA. These turtles were closely associated with warm effluent from a power plant during winter months. The life stage distribution of green turtles in the bay ranged from post-pelagic juveniles to adults (44.0–110.4 cm straight carapace length). During 99 capture sessions between December 2, 1990, and March 25, 2009, 96 individual green turtles were caught. To estimate abundance and survival rates, robust-design mark-recapture models were fitted to capture-recapture histories using software MARK. The estimated annual survival rate was 0.861 (SE = 0.147, 95% CI = 0.356–0.986), whereas annual abundance ranged from 16 (SE = 6.3, 95% CI = 4–29) to 61 (SE = 13.2, 95% CI = 36–88). This study provides the first survival rate and abundance estimates for a green turtle foraging population in the highly industrialized San Diego Bay.  相似文献   
9.
Interactions with fisheries are believed to be a major cause of mortality for adult leatherback turtles (Dermochelys coriacea), which is of particular concern in the Pacific Ocean, where they have been rapidly declining. In order to identify where these interactions are occurring and how they may be reduced, it is essential first to understand the movements and behavior of leatherback turtles. There are two regional nesting populations in the East Pacific (EP) and West Pacific (WP), comprising multiple nesting sites. We synthesized tracking data from the two populations and compared their movement patterns. A switching state-space model was applied to 135 Argos satellite tracks to account for observation error, and to distinguish between migratory and area-restricted search behaviors. The tracking data, from the largest leatherback data set ever assembled, indicated that there was a high degree of spatial segregation between EP and WP leatherbacks. Area-restricted search behavior mainly occurred in the southeast Pacific for the EP leatherbacks, whereas the WP leatherbacks had several different search areas in the California Current, central North Pacific, South China Sea, off eastern Indonesia, and off southeastern Australia. We also extracted remotely sensed oceanographic data and applied a generalized linear mixed model to determine if leatherbacks exhibited different behavior in relation to environmental variables. For the WP population, the probability of area-restricted search behavior was positively correlated with chlorophyll-a concentration. This response was less strong in the EP population, but these turtles had a higher probability of search behavior where there was greater Ekman upwelling, which may increase the transport of nutrients and consequently prey availability. These divergent responses to oceanographic conditions have implications for leatherback vulnerability to fisheries interactions and to the effects of climate change. The occurrence of leatherback turtles within both coastal and pelagic areas means they have a high risk of exposure to many different fisheries, which may be very distant from their nesting sites. The EP leatherbacks have more limited foraging grounds than the WP leatherbacks, which could make them more susceptible to any temperature or prey changes that occur in response to climate change.  相似文献   
10.
PCDDs/DFs emissions from crematories in Japan   总被引:1,自引:0,他引:1  
Concentrations of PCDDs and PCDFs in emission gases from 10 crematories were measured. The relationship between PCDDs/DFs and several factors such as structure, equipment and operational state of the crematory is discussed. Furthermore, emission of PCDDs/DFs from all crematories in Japan is estimated. The following results are obtained: (1) total concentration of PCDDs/DFs was 2.2-290 ng/N m3, whose TEQ concentration was 0.0099-6.5 ng TEQ/N m3; (2) total concentration of PCDFs was higher than that of PCDDs; (3) T4CDFs was the highest in the homologue pattern and 2,3,7,8-T4CDF was the highest in the isomer pattern; (4) emission of PCDDs/DFs was the largest in the first 20 min of cremation; (5) concentration of PCDDs/DFs was related to the existence of a secondary combustion chamber and a dust collector, and the ratio of the numbers of main and secondary combustion chambers; (6) total emission of PCDDs/DFs from crematories in Japan was estimated to be 8.9 g TEQ/yr.  相似文献   
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