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Solution by dilution?—A review on the pollution status of the Yangtze River Full text
2013
Floehr, Tilman | Xiao, Hongxia | Scholz-Starke, Björn | Wu, Lingling | Hou, Junli | Yin, Daqiang | Zhang, Xiaowei | Ji, Rong | Yuan, Xingzhong | Ottermanns, Richard | Roß-Nickoll, Martina | Schäffer, Andreas | Hollert, Henner
The Yangtze River has been a source of life and prosperity for the Chinese people for centuries and is a habitat for a remarkable variety of aquatic species. But the river suffers from huge amounts of urban sewage, agricultural effluents, and industrial wastewater as well as ship navigation wastes along its course. With respect to the vast amounts of water and sediments discharged by the Yangtze River, it is reasonable to ask whether the pollution problem may be solved by simple dilution. This article reviews the past two decades of published research on organic pollutants in the Yangtze River and several adjacent water bodies connected to the main stream, according to a holistic approach. Organic pollutant levels and potential effects of water and sediments on wildlife and humans, measured in vitro, in vivo, and in situ, were critically reviewed. The contamination with organic pollutants, including polycyclic aromatic hydrocarbons, polychlorinated biphenyls (PCBs), organochlorine pesticides (OCPs), polychlorinated dibenzo-p-dioxins/polychlorinated dibenzofurans, polybrominated diphenyl ethers (PBDEs), perfluorinated compounds (PFCs), and others, of water and sediment along the river was described. Especially Wuhan section and the Yangtze Estuary exhibited stronger pollution than other sections. Bioassays, displaying predominantly the endpoints mutagenicity and endocrine disruption, applied at sediments, drinking water, and surface water indicated a potential health risk in several areas. Aquatic organisms exhibited detectable concentrations of toxic compounds like PCBs, OCPs, PBDEs, and PFCs. Genotoxic effects could also be assessed in situ in fish. To summarize, it can be stated that dilution reduces the ecotoxicological risk in the Yangtze River, but does not eliminate it. Keeping in mind an approximately 14 times greater water discharge compared to the major European river Rhine, the absolute pollution mass transfer of the Yangtze River is of severe concern for the environmental quality of its estuary and the East China Sea. Based on the review, further research needs have been identified.
Show more [+] Less [-]Effects of chronic exposure to radiofrequency electromagnetic fields on energy balance in developing rats Full text
2013
Pelletier, Amandine | Delanaud, Stéphane | Décima, Pauline | Thuróczy, György | de Seze, René | Cerri, Matteo | Bach, Véronique | Libert, Jean-Pierre | Loos, Nathalie
The effects of radiofrequency electromagnetic fields (RF-EMF) on the control of body energy balance in developing organisms have not been studied, despite the involvement of energy status in vital physiological functions. We examined the effects of chronic RF-EMF exposure (900 MHz, 1 V m⁻¹) on the main functions involved in body energy homeostasis (feeding behaviour, sleep and thermoregulatory processes). Thirteen juvenile male Wistar rats were exposed to continuous RF-EMF for 5 weeks at 24 °C of air temperature (T ₐ) and compared with 11 non-exposed animals. Hence, at the beginning of the 6th week of exposure, the functions were recorded at T ₐ of 24 °C and then at 31 °C. We showed that the frequency of rapid eye movement sleep episodes was greater in the RF-EMF-exposed group, independently of T ₐ (+42.1 % at 24 °C and +31.6 % at 31 °C). The other effects of RF-EMF exposure on several sleep parameters were dependent on T ₐ. At 31 °C, RF-EMF-exposed animals had a significantly lower subcutaneous tail temperature (−1.21 °C) than controls at all sleep stages; this suggested peripheral vasoconstriction, which was confirmed in an experiment with the vasodilatator prazosin. Exposure to RF-EMF also increased daytime food intake (+0.22 g h⁻¹). Most of the observed effects of RF-EMF exposure were dependent on T ₐ. Exposure to RF-EMF appears to modify the functioning of vasomotor tone by acting peripherally through α-adrenoceptors. The elicited vasoconstriction may restrict body cooling, whereas energy intake increases. Our results show that RF-EMF exposure can induce energy-saving processes without strongly disturbing the overall sleep pattern.
Show more [+] Less [-]Biliary PAH metabolites, EROD activity and DNA damage in dab (Limanda limanda) from Seine Estuary (France) Full text
2013
Dévier, Marie-Hélène | Le Dû-Lacoste, Marie | Akcha, Farida | Morin, Bénédicte | Peluhet, Laurent | Le Menach, Karyn | Burgeot, Thierry | Budzinski, Hélène
The Seine Estuary is well known to be widely contaminated by organic pollutants and especially by polycyclic aromatic hydrocarbons (PAHs). Fish are known to metabolize PAHs, leading to different toxic effects at both cellular and sub-cellular levels. In this work, we studied the relationships between the 7-ethoxyresorufin-O-deethylase (EROD) activity in the liver, the level of DNA strand breaks in blood cells and the concentration of PAH metabolites in the bile of the sentinel flatfish species Limanda limanda. Muscle and liver samples were analysed for parent PAH levels. Female and male dabs of two size classes (juveniles and adults) were collected by trawling in two sites with different degrees of pollution during March and September 2005 and 2006. Significant effects of sex, age, site and season were demonstrated on EROD activity and the level of strand breaks. Parent PAH concentrations in dabs did not allow discriminating of the two sampling sites. However, for PAH metabolites, significant differences were observed with sites and seasons. Dabs collected at the mouth of the estuary appeared to be the most impacted when looking at the results obtained with the three selected markers. The significant correlations observed between the level of PAH metabolites and the level of DNA lesions showed the importance of a combined analysis of chemical and biochemical markers to correctly assess the contribution of chemical contamination to the toxic effects measured in situ in fish.
Show more [+] Less [-]Phosphorus loads from different urban storm runoff sources in southern China: a case study in Wenzhou City Full text
2013
Zhou, Dong | Bi, Chun-Juan | Chen, Zhen-Lou | Yu, Zhong-Jie | Wang, Jun | Han, Jing-Chao
Storm runoff from six types of underlying surface area during five rainfall events in two urban study areas of Wenzhou City, China was investigated to measure phosphorus (P) concentrations and discharge rates. The average event mean concentrations (EMCs) of total phosphorus (TP), total dissolved phosphorus (TDP), and particulate phosphorus (PP) ranged from 0.02 to 2.5 mg · L(-1), 0.01 to 0.48 mg · L(-1), and 0.02 to 2.43 mg · L(-1), respectively. PP was generally the dominant component of TP in storm runoff, while the major form of P varied over time, especially in roof runoff, where TDP made up the largest portion in the latter stages of runoff events. Both TP and PP concentrations were positively correlated with pH, total suspended solids (TSS), and biochemical oxygen demand (BOD)/chemical oxygen demand (COD) concentrations (p < 0.01), while TDP was positively correlated with BOD/COD only (p < 0.01). In addition, the EMCs of TP and PP were negatively correlated with maximum rainfall intensity (p < 0.05), while the EMCs of TDP positively correlated with the antecedent dry weather period (p < 0.05). The annual TP emission fluxes from the two study areas were 367.33 and 237.85 kg, respectively. Underlying surface type determined the TP and PP loadings in storm runoff, but regional environmental conditions affected the export of TDP more significantly. Our results indicate that the removal of particles from storm runoff could be an effective measure to attenuate P loadings to receiving water bodies.
Show more [+] Less [-]The impact of indoor air pollution on the incidence of life threatening respiratory illnesses: Evidence from young children in Peru Full text
2013
Gajate-Garrido, Gissele
Spatial modelling for nitrogen leaching from intensive farming in Red River Delta of Vietnam
2013
Mai, V. T. | Hoanh, Chu Thai | Van Keulen, H. | Hessel, R.
Spatial modelling for nitrogen leaching from intensive farming in Red River Delta of Vietnam
2013
Mai, V. T. | Hoanh, Chu Thai | Van Keulen, H. | Hessel, R.
In this study, a spatial dynamic model was developed, to simulate nitrogen dynamics in Van Hoi commune, Tam Duong district, Vietnam, for different soil and land use types, under different irrigation and fertilizer regimes. The model has been calibrated using measured nitrogen concentrations in soil solution in March and August 2004 and validated for data from March and August 2005. Lateral flow was low in this level area. Percolation was the main process leading to high nitrogen leaching losses to ground water. Calculated annual leaching losses varied from 88 to 122 kg N ha–1 in flowers, 64 to 82 in vegetables of the cabbage group, 51 to 76 in chili, 56 to 75 in vegetables of the squash group, and 36 to 55 in rice.
Show more [+] Less [-]Spatial modelling for nitrogen leaching from intensive farming in Red River Delta of Vietnam
2013
Mai, V.T. | Hoanh, Chu Thai | Keulen, H. van | Hessel, R.
In this study, a spatial dynamic model was developed, to simulate nitrogen dynamics in Van Hoi commune, Tam Duong district, Vietnam, for different soil and land use types, under different irrigation and fertilizer regimes. The model has been calibrated using measured nitrogen concentrations in soil solution in March and August 2004 and validated for data from March and August 2005. Lateral flow was low in this level area. Percolation was the main process leading to high nitrogen leaching losses to ground water. Calculated annual leaching losses varied from 88 to 122 kg N ha-1 in flowers, 64 to 82 in vegetables of the cabbage group, 51 to 76 in chili, 56 to 75 in vegetables of the squash group, and 36 to 55 in rice.
Show more [+] Less [-]A probabilistic model estimating oil spill clean-up costs - a case study for the Gulf of Finland Full text
2013
Montewka, Jakub | Weckström, Mia | Kujala, Pentti
A probabilistic model estimating oil spill clean-up costs - a case study for the Gulf of Finland Full text
2013
Montewka, Jakub | Weckström, Mia | Kujala, Pentti
Existing models estimating oil spill costs at sea are based on data from the past, and they usually lack a systematic approach. This make them passive, and limits their ability to forecast the effect of the changes in the oil combating fleet or location of a spill on the oil spill costs. In this paper we make an attempt towards the development of a probabilistic and systematic model estimating the costs of clean-up operations for the Gulf of Finland. For this purpose we utilize expert knowledge along with the available data and information from literature. Then, the obtained information is combined into a framework with the use of a Bayesian Belief Networks. Due to lack of data, we validate the model by comparing its results with existing models, with which we found good agreement. We anticipate that the presented model can contribute to the cost-effective oil-combating fleet optimization for the Gulf of Finland. It can also facilitate the accident consequences estimation in the framework of formal safety assessment (FSA).
Show more [+] Less [-]A probabilistic model estimating oil spill clean-up costs – A case study for the Gulf of Finland Full text
2013
Montewka, Jakub | Weckström, Mia | Kujala, P.
Existing models estimating oil spill costs at sea are based on data from the past, and they usually lack a systematic approach. This make them passive, and limits their ability to forecast the effect of the changes in the oil combating fleet or location of a spill on the oil spill costs.In this paper we make an attempt towards the development of a probabilistic and systematic model estimating the costs of clean-up operations for the Gulf of Finland. For this purpose we utilize expert knowledge along with the available data and information from literature. Then, the obtained information is combined into a framework with the use of a Bayesian Belief Networks. Due to lack of data, we validate the model by comparing its results with existing models, with which we found good agreement.We anticipate that the presented model can contribute to the cost-effective oil-combating fleet optimization for the Gulf of Finland. It can also facilitate the accident consequences estimation in the framework of formal safety assessment (FSA).
Show more [+] Less [-]Meteorology Full text
2013
Raspe, Stephan | Bastrup-Birk, Annemarie | Fleck, Stefan | Weis, Wendelin | Mayer, Helmut | Meesenburg, Henning | Wagner, Markus | Schindler, Dirk | Gartner, Karl
Seawater carbonate chemistry and reproductive properties of the benthic copepod Tigriopus japonicus and gastropod Babylonia japonica in a laboratory experiment Full text
2013
Kita, Jun | Kikkawa, Takashi | Asai, Takamasa | Ishimatsu, Atsushi
Seawater carbonate chemistry and reproductive properties of the benthic copepod Tigriopus japonicus and gastropod Babylonia japonica in a laboratory experiment Full text
2013
Kita, Jun | Kikkawa, Takashi | Asai, Takamasa | Ishimatsu, Atsushi
We investigated the effects of elevated pCO2 in seawater both on the acute mortality and the reproductive properties of the benthic copepod Tigriopus japonicus and gastropod Babylonia japonica with the purpose of accumulating basic data for assessing potential environmental impacts of sub-sea geological storage of anthropogenic CO2 in Japan. Acute tests showed that nauplii of T. japonicus have a high tolerance to elevated pCO2 environments. Full life cycle tests on T. japonicus indicated NOEC = 5800 µatm and LOEC = 37,000 µatm. Adult B. japonica showed remarkable resistance to elevated pCO2 in the acute tests. Embryonic development of B. japonica showed a NOEC = 1500 µatm and LOEC = 5400 µatm. T. japonicus showed high resistance to elevated pCO2 throughout the life cycle and B. japonica are rather sensitive during the veliger stage when they started to form their shells.
Show more [+] Less [-]Effects of elevated pCO2 on reproductive properties of the benthic copepod Tigriopus japonicus and gastropod Babylonia japonica Full text
2013
We investigated the effects of elevated pCO2 in seawater both on the acute mortality and the reproductive properties of the benthic copepod Tigriopus japonicus and gastropod Babylonia japonica with the purpose of accumulating basic data for assessing potential environmental impacts of sub-sea geological storage of anthropogenic CO2 in Japan. Acute tests showed that nauplii of T. japonicus have a high tolerance to elevated pCO2 environments. Full life cycle tests on T. japonicus indicated NOEC=5800μatm and LOEC=37,000μatm. Adult B. japonica showed remarkable resistance to elevated pCO2 in the acute tests. Embryonic development of B. japonica showed a NOEC=1500μatm and LOEC=5400μatm. T. japonicus showed high resistance to elevated pCO2 throughout the life cycle and B. japonica are rather sensitive during the veliger stage when they started to form their shells.
Show more [+] Less [-]Seawater carbonate chemistry and reproduction of the two calanoid copepods Centropages typicus and Temora longicornis in a laboratory experiment Full text
2013
McConville, Kristian | Halsband, Claudia | Fileman, Elaine S | Somerfield, Paul J | Findlay, Helen S | Spicer, John I
Seawater carbonate chemistry and reproduction of the two calanoid copepods Centropages typicus and Temora longicornis in a laboratory experiment Full text
2013
McConville, Kristian | Halsband, Claudia | Fileman, Elaine S | Somerfield, Paul J | Findlay, Helen S | Spicer, John I
Some planktonic groups suffer negative effects from ocean acidification (OA), although copepods might be less sensitive. We investigated the effect of predicted CO2 levels (range 480-750 ppm), on egg production and hatching success of two copepod species, Centropages typicus and Temora longicornis. In these short-term incubations there was no significant effect of high CO2 on these parameters. Additionally a very high CO2 treatment, (CO2 = 9830 ppm), representative of carbon capture and storage scenarios, resulted in a reduction of egg production rate and hatching success of C. typicus, but not T. longicornis. In conclusion, reproduction of C. typicus was more sensitive to acute elevated seawater CO2 than that of T. longicornis, but neither species was affected by exposure to CO2 levels predicted for the year 2100. The duration and seasonal timing of exposures to high pCO2, however, might have a significant effect on the reproduction success of calanoid copepods.
Show more [+] Less [-]Effects of elevated CO2 on the reproduction of two calanoid copepods Full text
2013
McConville, Kristian | Halsband, Claudia | Fileman, Elaine S. | Somerfield, Paul J. | Findlay, Helen S. | Spicer, John I.
Some planktonic groups suffer negative effects from ocean acidification (OA), although copepods might be less sensitive. We investigated the effect of predicted CO2 levels (range 480–750ppm), on egg production and hatching success of two copepod species, Centropages typicus and Temora longicornis. In these short-term incubations there was no significant effect of high CO2 on these parameters. Additionally a very high CO2 treatment, (CO2=9830ppm), representative of carbon capture and storage scenarios, resulted in a reduction of egg production rate and hatching success of C. typicus, but not T. longicornis. In conclusion, reproduction of C. typicus was more sensitive to acute elevated seawater CO2 than that of T. longicornis, but neither species was affected by exposure to CO2 levels predicted for the year 2100. The duration and seasonal timing of exposures to high pCO2, however, might have a significant effect on the reproduction success of calanoid copepods.
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