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Trace elements pollution and toxicity of airborne PM10 in a coal industrial city Full text
2015
Xiaoyan, Song | Longyi, Shao | Shushen, Yang | Riying, Song | Limei, Sun | Shihong, Cen
Trace elements in particulate matter associated with coal industries hold high risk to human health. Understanding the contents and occurrences of modes of these elements as well as their contribution to particulate toxicity is significant both environmentally and pathologically. A total of 24 PM10 samples were collected in Pingdingshan City, a coal industrial city in North China, in both winter and summer of 2008. An inductively coupled plasma mass spectrometry (ICP–MS) was used to determine the concentrations of 12 trace elements associated with coal industries (Cr, Ni, Cu, Zn, As, Mo, Cd, Sn, Sb, Tl, Pb, and Bi) in PM10 samples. The results indicated that the trace element concentrations were higher in winter than in summer; due mainly to more coal combustion during winter and to the different meteorological conditions of these two seasons. The soluble proportions of these trace elements compared with total values of intact whole samples were higher in winter than in summer, and this difference was attributed mainly to more SO2 reacting with pre–existing particles to form soluble particles in winter. Of all the analyzed elements, Ni, Tl, Sb, Mo, and Cd occurred mainly in the soluble state (>50% in the soluble fraction), Cr, Cu, Zn, and As occurred in both the soluble and insoluble state (20% to 50% in the soluble fraction), and Sn, Pb, and Bi occurred mainly in the insoluble state (<20% in the soluble fraction). A plasmid DNA assay indicated that winter samples had higher toxicity than summer samples. The correlation of PM10 toxicity (TD50 value) with the contribution of various trace elements to DNA damage (trace element concentration) was further analyzed, and the results indicated that PM10 toxicity was caused mainly by the soluble fractions of trace elements, including those of Ni, Pb, Cu, Cd, As, Zn, Cr, and Tl, which were the major toxic trace elements in Pingdingshan PM10.
Show more [+] Less [-]Determination of mercury and vanadium concentration in Johnius belangerii (C) fish in Musa estuary in Persian Gulf Full text
2015
Fard, Neamat Jaafarzadeh Haghighi | Ravanbakhsh, Maryam | Ramezani, Zahra | Ahmadi, Mehdi | Angali, Kambiz Ahmadi | Javid, Ahmad Zare
The main aim of this study was to determine the concentrations of mercury and vanadium in Johnius belangerii (C) fish in the Musa estuary. A total of 67 fishes were caught from the Musa estuary during five intervals of 15days in the summer of 2013. After biometric measurements were conducted, the concentrations of mercury and vanadium were measured in the muscle tissue of fish using a direct method analyzer (DMA) and a graphite furnace atomic absorption spectrophotometer, respectively. The mean concentration of mercury and vanadium in the muscle tissue of fish was 3.154±1.981 and 2.921±0.873mg/kg w.w, respectively. The generalized linear model (GLM) analysis showed a significantly positive relationship among mercury concentration, length, and weight (P=0.000). In addition, there was a significantly negative relationship between vanadium concentration and fish length (P=0.000). A reverse association was found between concentrations of mercury and vanadium. Mercury concentration exceeded the allowable standards of the Environmental Protection Agency (EPA), the World Health Organization (WHO), and the Food and Drug Administration (FDA) in J. belangerii (C).
Show more [+] Less [-]Marine governance in the English Channel (La Manche): Linking science and management Full text
2015
Glegg, G. | Jefferson, R. | Fletcher, S.
The English Channel is one of the world’s busiest sea areas with intense shipping and port activity juxtaposed with recreation, communications and important conservation areas. Opportunities for marine renewable energy vie with existing activities for space. The current governance of the English Channel is reviewed and found to lack integration between countries, sectors, legislation and scientific research. Recent developments within the EU’s marine management frameworks are significantly altering our approach to marine governance and this paper explores the implications of these new approaches to management of the English Channel. Existing mechanisms for cross-Channel science and potential benefits of an English Channel scale perspective are considered. In conclusion, current management practices are considered against the 12 Malawi Principles of the ecosystem approach resulting in proposals for enhancing governance of the region through science at the scale of the English Channel.
Show more [+] Less [-]Recovery of a subtropical rocky shore is not yet complete, four years after a moderate sized oil spill Full text
2015
Finlayson, Kimberly | Stevens, Tim | Arthur, James Michael | Rissik, David
Little is known about the recovery trajectory from small to moderate spills (<1000t), particularly in the sub-tropics. On 11 March 2009 the MV Pacific Adventurer spilt 270t of bunker fuel oil 13km off Moreton Island, Australia, impacting wetlands, sandy beaches and rocky shores. This study examines the recovery of the rocky shore community four years after the spill. Results indicate that recovery on Moreton Island is taking longer than the 3–4years suggested by the literature. The upper shore is recovering faster than the mid shore and is nearly recovered while the mid shore is still in the recovery process. These results indicate that small to moderate sized spills can have environmental impacts on par with much larger spills and emphasizes the need for a clear definition of a recovery endpoint. Long term studies are required to gain a full understanding of trajectories of recovery after oil spill impacts.
Show more [+] Less [-]Combining molecular fingerprints with multidimensional scaling analyses to identify the source of spilled oil from highly similar suspected oils Full text
2015
Zhou, Peiyu | Chen, Changshu | Ye, Jianjun | Shen, Wenjie | Xiong, Xiaofei | Hu, Ping | Fang, Hongda | Huang, Chuguang | Sun, Yongge
Oil fingerprints have been a powerful tool widely used for determining the source of spilled oil. In most cases, this tool works well. However, it is usually difficult to identify the source if the oil spill accident occurs during offshore petroleum exploration due to the highly similar physiochemical characteristics of suspected oils from the same drilling platform. In this report, a case study from the waters of the South China Sea is presented, and multidimensional scaling analysis (MDS) is introduced to demonstrate how oil fingerprints can be combined with mathematical methods to identify the source of spilled oil from highly similar suspected sources. The results suggest that the MDS calculation based on oil fingerprints and subsequently integrated with specific biomarkers in spilled oils is the most effective method with a great potential for determining the source in terms of highly similar suspected oils.
Show more [+] Less [-]Electrospun PS/PAN fibers with improved mechanical property for removal of oil from water Full text
2015
Li, Peng | Qiao, Ying | Zhao, Lili | Yao, Dahu | Sun, Haixiang | Hou, Yingfei | Li, Shuo | Li, Qi
A mechanically robust and high-capacity oil sorbent is prepared by electrospinning a blend of polystyrene (PS) and polyacrylonitrile (PAN). The morphology, oil sorption capacity and mechanical property of the fibers formed in different compositions are investigated in detail. It is shown that the oil sorption capacity is a result of both the chemical composition and the specific surface area which related to diameter size. The addition of PAN as a component in fibrous sorbents can significantly improve the mechanical properties of PS fibers. Moreover, the oil sorption capacity increases with decreasing fiber diameter. The results also show that the maximum sorption capacities of the PS/PAN sorbent for pump oil, peanut oil, diesel, and gasoline were 194.85, 131.70, 66.75, and 43.38gg−1, respectively. Additionally, the sorbent exhibits quick oil sorption speed as well as high buoyancy, which make it a promising candidate for use as an oil spill cleanup sorbent.
Show more [+] Less [-]Assessment of microplastic toxicity to embryonic development of the sea urchin Lytechinus variegatus (Echinodermata: Echinoidea) Full text
2015
Nobre, C.R. | Santana, M.F.M. | Maluf, A. | Cortez, F.S. | César, A. | Pereira, C.D.S. | Turra, A.
Apart from the physiological impacts on marine organisms caused by ingesting microplastics, the toxicity caused by substances leaching from these particles into the environment requires investigation. To understand this potential risk, we evaluated the toxicity of virgin (raw) and beach-stranded plastic pellets to the development of embryos of Lytechinus variegatus, simulating transfers of chemical compounds to interstitial water and water column by assays of pellet–water interface and elutriate, respectively. Both assays showed that virgin pellets had toxic effects, increasing anomalous embryonic development by 58.1% and 66.5%, respectively. The toxicity of stranded pellets was lower than virgin pellets, and was observed only for pellet–water interface assay. These results show that (i) plastic pellets act as a vector of pollutants, especially for plastic additives found on virgin particles; and that (ii) the toxicity of leached chemicals from pellets depends on the exposure pathway and on the environmental compartment in which pellets accumulate.
Show more [+] Less [-]Selective extraction and concentration of mebendazole in seawater samples using molecularly imprinted polymer as sorbent Full text
2015
Lian, Ziru | Liang, Zhenlin | Wang, Jiangtao
A high selective pre-treatment method for the extraction and analysis of mebendazole in environmental water samples was developed based on molecularly imprinted solid-phase extraction (MISPE). The mebendazole imprinted polymers were synthesized in acetonitrile using methacrylic acid and ethylene glycol dimethacrylate as functional monomer and cross-linker respectively. The imprinted materials showed high adsorption ability for mebendazole and were applied as special solid-phase extraction sorbents for selective separation of mebendazole. An off-line MISPE procedure was developed for the purification and enrichment of mebendazole from natural seawater samples prior to high-performance liquid chromatography analysis. The recoveries of spiked seawater on the MISPE cartridges were from 83.0% to 90.6%, and the values of the relative standard deviation were in the range of 2.78–4.13% (n=3). The satisfied results showed that this pre-treatment methodology for extracting mebendazole in seawater was simple and effective.
Show more [+] Less [-]Evaluation of beach cleanup effects using linear system analysis Full text
2015
Kataoka, Tomoya | Hinata, Hirofumi
We established a method for evaluating beach cleanup effects (BCEs) based on a linear system analysis, and investigated factors determining BCEs. Here we focus on two BCEs: decreasing the total mass of toxic metals that could leach into a beach from marine plastics and preventing the fragmentation of marine plastics on the beach. Both BCEs depend strongly on the average residence time of marine plastics on the beach (τr) and the period of temporal variability of the input flux of marine plastics (T). Cleanups on the beach where τr is longer than T are more effective than those where τr is shorter than T. In addition, both BCEs are the highest near the time when the remnants of plastics reach the local maximum (peak time). Therefore, it is crucial to understand the following three factors for effective cleanups: the average residence time, the plastic input period and the peak time.
Show more [+] Less [-]Surfactants in the sea-surface microlayer and sub-surface water at estuarine locations: Their concentration, distribution, enrichment, and relation to physicochemical characteristics Full text
2015
Huang, Yun-Jie | Brimblecombe, Peter | Lee, Chon-Lin | Latif, Mohd Talib
Samples of sea-surface microlayer (SML) and sub-surface water (SSW) were collected from two areas-Kaohsiung City (Taiwan) and the southwest coast of Peninsular Malaysia to study the influence of SML on enrichment and distribution and to compare SML with the SSW. Anionic surfactants (MBAS) predominated in this study and were significantly higher in Kaohsiung than in Malaysia. Industrial areas in Kaohsiung were enriched with high loads of anthropogenic sources, accounted for higher surfactant amounts, and pose higher environmental disadvantages than in Malaysia, where pollutants were associated with agricultural activities.The dissolved organic carbon (DOC), MBAS, and cationic surfactant (DBAS) concentrations in the SML correlated to the SSW, reflecting exchanges between the SML and SSW in Kaohsiung. The relationships between surfactants and the physiochemical parameters indicated that DOC and saltwater dilution might affect the distributions of MBAS and DBAS in Kaohsiung. In Malaysia, DOC might be the important factor controlling DBAS.
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