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Inventory development for perfluorooctane sulfonic acid (PFOS) in Turkey: challenges to control chemicals in articles and products Полный текст
2015
Korucu, M Kemal | Gedik, Kadir | Weber, Roland | Karademir, Aykan | Kurt-Karakus, Perihan Binnur
Perfluorooctane sulfonic acid (PFOS) and related substances have been listed as persistent organic pollutants (POPs) in the Stockholm Convention. Countries which have ratified the Convention need to take appropriate actions to control PFOS use and release. This study compiles and enhances the findings of the first inventory of PFOS and related substances use in Turkey conducted within the frame of the Stockholm Convention National Implementation Plan (NIP) update. The specific Harmonized Commodity Description and Coding System (Harmonized System (HS)) codes of imported and exported goods that possibly contain PFOS and 165 of Chemical Abstracts Service (CAS) numbers of PFOS-related substances were assessed for acquiring information from customs and other authorities. However, with the current approaches available, no useful information could be compiled since HS codes are not specific enough and CAS numbers are not used by customs. Furthermore, the cut-off volume in chemical databases in Turkey and the reporting limit in the HS system (0.1 %) are too high for controlling PFOS. The attempt of modeling imported volumes by a Monte Carlo simulation did not also result in a satisfactory estimate, giving an upper-bound estimate above the global production volumes. The replies to questionnaires were not satisfactory, highlighting that an elaborated approach is needed in the communication with potentially PFOS-using stakeholders. The experience of the challenges of gathering information on PFOS in articles and products revealed the gaps of controlling highly hazardous substances in products and articles and the need of improvements.
Показать больше [+] Меньше [-]Trace element fluxes in sediments of an environmentally impacted river from a coastal zone of Brazil Полный текст
2015
da Silva, Yuri Jacques Agra Bezerra | Cantalice, José Ramon Barros | Singh, V. P. (Vijay P.) | do Nascimento, Clístenes Williams Araújo | Piscoya, Victor Casimiro | Guerra, Sérgio M. S.
Data regarding trace element concentrations and fluxes in suspended sediments and bedload are scarce. To fill this gap and meet the international need to include polluted rivers in future world estimation of trace element fluxes, this study aimed to determine the trace element fluxes in suspended sediment and bedload of an environmentally impacted river in Brazil. Water, suspended sediment, and bedload from both the upstream and the downstream cross sections were collected. To collect both the suspended sediment and water samples, we used the US DH-48. Bedload measurements were carried out using the US BLH 84 sampler. Concentrations of Cd, Cr, Cu, Fe, Mn, Ni, Pb, and Zn were determined by inductively coupled plasma (ICP-OES). As and Hg were determined by an atomic absorption spectrophotometer (AA-FIAS). The suspended sediments contributed more than 99 % of the trace element flux. By far Pb and to a less extent Zn at the downstream site represents major concerns. The yields of Pb and Zn in suspended sediments were 4.20 and 2.93 kg km² year⁻¹, respectively. These yields were higher than the values reported for Pb and Zn for Tuul River (highly impacted by mining activities), 1.60 and 1.30 kg km² year⁻¹, respectively, as well as the Pb yield (suspended + dissolved) to the sea of some Mediterranean rivers equal to 3.4 kg km² year⁻¹. Therefore, the highest flux and yield of Pb and Zn in Ipojuca River highlighted the importance to include medium and small rivers—often overlooked in global and regional studies—in the future estimation of world trace element fluxes in order to protect estuaries and coastal zones.
Показать больше [+] Меньше [-]Role of hydrological conditions on organic phosphorus forms and their availability in sediments from Poyang Lake, China Полный текст
2015
Ni, Zhaokui | Wang, Shengrui | Zhang, Li | Wu, Zhiqiang
Biogeochemical cycling of internal bioavailable organic phosphorus (OP) is an important source for algal bloom after exogenous P inputs are controlled. Biogeochemical cycling may be affected by hydrological processes and the water cycle and eventually result in water quality deterioration and accelerated lake eutrophication. Poyang Lake is the largest freshwater lake in China. The hydrological condition of the lake has significantly changed since 2003, thereby causing a continuous decline in water level. In this study, sediments were obtained from different elevations and different hydrological conditions in Poyang Lake. The sediments were subjected to sequential extraction and enzymatic hydrolysis to determine the transformation of OP into various chemical forms, their bioavailability, and the exchange between the sediments and overlying water. Results suggested that the descending water level caused by the changes in hydrological conditions was one of the major factors affecting OP dynamics. Long exposure of sediments resulted in high OP content and increased availability. The increased OP content in exposed sediments was primarily derived from H₂O-Pₒ and NaOH-EDTA-Pₒ. Moreover, the increased OP availability in exposed sediments was mainly attributed to the increasing amount of orthophosphate caused by processes governing sediment exposure, promotion of OP release, and transformation of chemical forms from nonlabile to labile. Sediment exposure time and area have considerably expanded since 2003; hence, the amounts of OP and orthophosphate in the sediments have increased by as much as 600 and 120 tons in the lake every year, respectively. Although the increase in orthophosphate only accounted for 6 % of the external total phosphorus, the local region may exhibit higher risk for OP release from the sediments, thereby accelerating quality deterioration. Therefore, maintaining reasonable hydrological conditions is important to protect Poyang Lake water.
Показать больше [+] Меньше [-]Mineral and organic compounds in leachate from landfill with concentrate recirculation Полный текст
2015
Talalaj, Izabela Anna
The effect of a reverse osmosis concentrate recirculation on the mineral and organic compounds in a landfill leachate was investigated. Investigated was the quality of a leachate from two landfills operated for different periods (a 20-year-old Cell A and a 1-year-old Cell B), where the concentrate was recirculated. Examined were general parameters (conductivity, pH), organic compounds (biochemical oxygen demand (BOD), chemical oxygen demand (COD), total organic nitrogen, BOD/COD), and inorganic compounds (nitrogen ammonia, sulfite, sulfate, cyanide, boron, chloride, ferrous, zinc, chrome, copper). The findings from the first year of investigation showed that over the initial period of recirculation, the concentration of organic compounds (BOD, COD) increased, but after 6 months their values stabilized. It indicates that the concentrate recirculation accelerated organic decomposition, especially in the new landfill Cell. The analysis of inorganic parameters showed that recirculation landfills produce a leachate with a higher concentration of N-NH₄, and Cl⁻. In case of the old landfill Cell, an increase in B and Fe was also noticeable. These compounds are cyclically washed out from a waste dump and require an additional pretreatment in order to exclude them from recirculation cycle. The increased concentration of Cu, Zn, and Fe was noticed during the initial months of recirculation and in the season of intense atmospheric precipitation in the leachate from both Cells. Higher values of electro conductivity, Cl⁻, N-NH₄⁺, B, and Fe in the leachate from the old field indicate that the attenuation capacity of this landfill is close to exhaustion.
Показать больше [+] Меньше [-]Effects of peat fires on the characteristics of humic acid extracted from peat soil in Central Kalimantan, Indonesia Полный текст
2015
Yustiawati, | Kihara, Yusuke | Sazawa, Kazuto | Kuramitz, Hideki | Kurasaki, Masaaki | Saito, Takeshi | Hosokawa, Toshiyuki | Syawal, M Suhaemi | Wulandari, Linda | Hendri I, | Tanaka, Shunitz
When peat forest fires happen, it leads to burn soil and also humic acids as a dominant organic matter contained in peat soil as well as the forest. The structure and properties of humic acids vary depending on their origin and environment, therefore the transformation of humic acid is also diverse. The impacts of the peat fires on peat soil from Central Kalimantan, Indonesia were investigated through the characterization of humic acids, extracted from soil in burnt and unburnt sites. The characterization of humic acids was performed by elemental composition, functional groups, molecular weight by HPSEC, pyrolysate compounds by pyrolysis-GC/MS, fluorescence spectrum by 3DEEM spectrofluorometer, and thermogravimetry. The elemental composition of each humic substance indicated that the value of H/C and O/C of humic acids from burnt sites were lower than that from unburnt sites. The molecular weight of humic acids from burnt sites was also lower than that from unburnt sites. Pyrolysate compounds of humic acids from unburnt sites differed from those of humic acids from burnt soil. The heating experiment showed that burning process caused the significant change in the properties of humic acids such as increasing the aromaticity and decreasing the molecular weight.
Показать больше [+] Меньше [-]Analysis of airborne pesticides from different chemical classes adsorbed on Radiello® Tenax® passive tubes by thermal-desorption-GC/MS Полный текст
2015
Raeppel, Caroline | Fabritius, Marie | Nief, Marie | Appenzeller, Brice M. R. | Briand, Olivier | Tuduri, Ludovic | Millet, Maurice
An analytical methodology using automatic thermal desorption (ATD) and GC/MS was developed for the determination of 28 pesticides of different chemical classes (dichlobenil, carbofuran, trifluralin, clopyralid, carbaryl, flazasulfuron, mecoprop-P, dicamba, 2,4-MCPA, dichlorprop, 2,4-D, triclopyr, cyprodinil, bromoxynil, fluroxypyr, oxadiazon, myclobutanil, buprofezin, picloram, trinexapac-p-ethyl, ioxynil, diflufenican, tebuconazole, bifenthrin, isoxaben, alphacypermethrin, fenoxaprop and tau-fluvalinate) commonly used in nonagricultural areas in atmospheric samples. This methodology was developed to evaluate the indoor and outdoor atmospheric contamination by nonagricultural pesticides. Pesticides were sampled passive sampling tubes containing Tenax® adsorbent. Since most of these pesticides are polar (clopyralid, mecoprop-P, dicamba, 2,4-MCPA, dichlorprop, 2,4-D, triclopyr, bromoxynil, fluroxypyr, picloram, trinexapac-p-ethyl and ioxynil), a derivatisation step is required. For this purpose, a silylation step using N-(t-butyldimethylsilyl)-N-methyltrifluoroacetamide (MtBSTFA) was added before thermal desorption. This agent was chosen since it delivers very specific ions on electronic impact (m/z = M-57). This method was established with special consideration for optimal thermal desorption conditions (desorption temperature, desorb flow and duration; trap heating duration and flow; outlet split), linear ranges, limits of quantification and detection which varied from 0.005 to 10 ng and from 0.001 to 2.5 ng, respectively, for an uncertainty varied from 8 to 30 %. The method was applied in situ to the analysis of passive tubes exposed during herbicide application to an industrial site in east of France.
Показать больше [+] Меньше [-]A survey of smart water quality monitoring system Полный текст
2015
Dong, Jianhua | Wang, Guoyin | Yan, Huyong | Xu, Ji | Zhang, Xuerui
The smart water quality monitoring, regarded as the future water quality monitoring technology, catalyzes progress in the capabilities of data collection, communication, data analysis, and early warning. In this article, we survey the literature till 2014 on the enabling technologies for the Smart Water Quality Monitoring System. We explore three major subsystems, namely the data collection subsystem, the data transmission subsystem, and the data management subsystem from the view of data acquiring, data transmission, and data analysis. Specifically, for the data collection subsystem, we explore selection of water quality parameters, existing technology of online water quality monitoring, identification of the locations of sampling stations, and determination of the sampling frequencies. For the data transmission system, we explore data transmission network architecture and data communication management. For the data management subsystem, we explore water quality analysis and prediction, water quality evaluation, and water quality data storage. We also propose possible challenges and future directions for each subsystem.
Показать больше [+] Меньше [-]Methane and CO2 emissions from China’s hydroelectric reservoirs: a new quantitative synthesis Полный текст
2015
Li, Siyue | Zhang, Quanfa | Bush, Richard T. | Sullivan, Leigh A.
Controversy surrounds the green credentials of hydroelectricity because of the potentially large emission of greenhouse gases (GHG) from associated reservoirs. However, limited and patchy data particularly for China is constraining the current global assessment of GHG releases from hydroelectric reservoirs. This study provides the first evaluation of the CO₂and CH₄emissions from China’s hydroelectric reservoirs by considering the reservoir water surface and drawdown areas, and downstream sources (including spillways and turbines, as well as river downstream). The total emission of 29.6 Tg CO₂/year and 0.47 Tg CH₄/year from hydroelectric reservoirs in China, expressed as CO₂equivalents (eq), corresponds to 45.6 Tg CO₂eq/year, which is 2-fold higher than the current GHG emission (ca. 23 Tg CO₂eq/year) from global temperate hydropower reservoirs. China’s average emission of 70 g CO₂eq/kWh from hydropower amounts to 7 % of the emissions from coal-fired plant alternatives. China’s hydroelectric reservoirs thus currently mitigate GHG emission when compared to the main alternative source of electricity with potentially far great reductions in GHG emissions and benefits possible through relatively minor changes to reservoir management and design. On average, the sum of drawdown and downstream emission including river reaches below dams and turbines, which is overlooked by most studies, represents the equivalent of 42 % of the CO₂and 92 % of CH₄that emit from hydroelectric reservoirs in China. Main drivers on GHG emission rates are summarized and highlight that water depth and stratification control CH₄flux, and CO₂flux shows significant negative relationships with pH, DO, and Chl-a. Based on our finding, a substantial revision of the global carbon emissions from hydroelectric reservoirs is warranted.
Показать больше [+] Меньше [-]Human food safety and environmental hazards associated with the use of methyltestosterone and other steroids in production of all-male tilapia Полный текст
2015
Mlalila, Nichrous | Mahika, Charles | Kalombo, Lonji | Swai, Hulda | Hilonga, Askwar
In recent years, all-male cultures of Nile tilapia (Oreochromis niloticus) have been the most preferred mode of production in aquaculture industry. All-male individuals achieve higher somatic growth rate and shut high energy losses associated with gonadal development and reproduction. The economic advantages of culturing all-male tilapia have led to the development of procedures for producing unisex cultures, using 17α-methyltestosterone (MT). Despite widespread use of the MT in tilapia farming, the implications of hormone treatment in relation to human health and the environment have raised a number of concerns in the scientific community. In this review, the hormonal application processes, economic and ecological significance of MT, food safety and residual MT, comparative uses of steroids in aquaculture, animal husbandry, and medicine have been briefly reviewed for regulatory guidelines, and finally, future research perspectives have been addressed. The review can be used as policy-making guidelines in aquaculture framework development as can be emphasized in African continent, among others. The most important conclusion to draw is that the quantity of MT used in conventional practice is large compared to the actual dose required for sex reversal, fish produced are safe for human consumptions, and the environmental hazards should be further emphasized.
Показать больше [+] Меньше [-]Amplified solubilization effects of inherent dissolved organic matter releasing from less-humified sediment on phenanthrene sorption Полный текст
2015
Zhang, Xiaoyan | Wu, Yaoguo | Hu, Sihai | Lu, Cong | Zhang, Chengjun
Soil/sediment organic matter (SOM) releasing with inherent dissolved organic matter (DOM) formed in solution was confirmed both in rhizosphere sediment (S) and uncultivated sediment (P) water systems, and correlations between SOM characteristics subject to sediment’s humification degree and its releasing effects on phenanthrene sorption were emphasized. The sequential SOM releasing evidenced by fluorescence and ¹H-NMR profiles coupled with aqueous DOM solubilization was found to make sorption kinetics atypical and sorption capacity reduced, by comparing sorption results among sediments of different pretreatments. More importantly, the tested S was proved less humified with inherent DOM rich in microbial sources than P, and DOM affinity to phenanthrene was thus weakened (K dₒc values of 2.02–3.63 × 10⁴ L kg⁻¹), while the inhibitive effects of SOM releasing on sorption were strengthened, ascribing to the enlarged alterations of sediment characters, and particularly the amplified solubilization effects resulted from the larger proportion of soluble SOM and lower critical micelle concentration (5.66 mg L⁻¹) of DOM. Moreover, relative contribution of DOM solubilization to the releasing effects enhanced from 0.67 for P to 0.78 for S relative to alterations of sediment characters. Consequently, mobility and exposure risk of polycyclic aromatic hydrocarbons would be enhanced in a plant-soil/sediment-water system.
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