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Urban and rural mortality rates during heat waves in Berlin and Brandenburg, Germany
2011
Gabriel, Katharina M.A. | Endlicher, Wilfried R.
In large cities such as Berlin, human mortality rates increase during intense heat waves. Analysis of relevant data from north-eastern Germany revealed that, during the heat waves that occurred between 1990 and 2006, health risks were higher for older people in both rural and urban areas, but that, during the two main heat waves within that 17-year period of time, the highest mortality rates were from the city of Berlin, and in particular from its most densely built-up districts. Adaptation measures will need to be developed, particularly within urban areas, in order to cope with the expected future intensification of heat waves due to global climate change.
Show more [+] Less [-]Assessing the relationship between global warming and mortality: Lag effects of temperature fluctuations by age and mortality categories
2011
Yu, Weiwei | Mengersen, Kerrie | Hu, Wenbiao | Guo, Yuming | Pan, Xiaochuan | Tong, Shilu
Although interests in assessing the relationship between temperature and mortality have arisen due to climate change, relatively few data are available on lag structure of temperature–mortality relationship, particularly in the Southern Hemisphere. This study identified the lag effects of mean temperature on mortality among age groups and death categories using polynomial distributed lag models in Brisbane, Australia, a subtropical city, 1996–2004. For a 1 °C increase above the threshold, the highest percent increase in mortality on the current day occurred among people over 85 years (7.2% (95% CI: 4.3%, 10.2%)). The effect estimates among cardiovascular deaths were higher than those among all-cause mortality. For a 1 °C decrease below the threshold, the percent increases in mortality at 21 lag days were 3.9% (95% CI: 1.9%, 6.0%) and 3.4% (95% CI: 0.9%, 6.0%) for people aged over 85 years and with cardiovascular diseases, respectively. These findings may have implications for developing intervention strategies to reduce and prevent temperature-related mortality.
Show more [+] Less [-]Antagonism of phenanthrene cytotoxicity for human embryo lung fibroblast cell line HFL-I by green tea polyphenols
2011
Mei, Xin | Wu, Yuan-yuan | Mao, Xiao | Tu, You-Ying
Polycyclic aromatic hydrocarbons (PAHs) have been detected in some commercial teas around the world and pose a threat to tea consumers. However, green tea polyphenols (GTP) possess remarkable antioxidant and anticancer effects. In this study, the potential of GTP to block the toxicity of the model PAH phenanthrene was examined in human embryo lung fibroblast cell line HFL-I. Both GTP and phenanthrene treatment individually caused dose-dependent inhibition of cell growth. A full factorial design experiment demonstrated that the interaction of phenanthrene and GTP significantly reduced growth inhibition. Using the median effect method showed that phenanthrene and GTP were antagonistic when the inhibitory levels were less than about 50%. Apoptosis and cell cycle detection suggested that only phenanthrene affected cell cycle significantly and caused cell death; GTP lowered the mortality of HFL-I cells exposed to phenanthrene; However, GTP did not affect modulation of the cell cycle by phenanthrene.
Show more [+] Less [-]The effect of atmospheric thermal conditions and urban thermal pollution on all-cause and cardiovascular mortality in Bangladesh
2011
Burkart, Katrin | Schneider, Alexandra | Breitner, Susanne | Khan, Md. Mobarak Hossain | Krämer, Alexander | Endlicher, Wilfried
This study assessed the effect of temperature and thermal atmospheric conditions on all-cause and cardiovascular mortality in Bangladesh. In particular, differences in the response to elevated temperatures between urban and rural areas were investigated. Generalized additive models (GAMs) for daily death counts, adjusted for trend, season, day of the month and age were separately fitted for urban and rural areas. Breakpoint models were applied for determining the increase in mortality above and below a threshold (equivalent) temperature. Generally, a ’V’-shaped (equivalent) temperature–mortality curve with increasing mortality at low and high temperatures was observed. Particularly, urban areas suffered from heat-related mortality with a steep increase above a specific threshold. This adverse heat effect may well increase with ongoing urbanization and the intensification of the urban heat island due to the densification of building structures. Moreover, rising temperatures due to climate change could aggravate thermal stress.
Show more [+] Less [-]Modeling time-dependent toxicity to aquatic organisms from pulsed exposure of PAHs in urban road runoff
2011
Zhang, Wei | Ye, Youbin | Tong, Yindong | Ou, Langbo | Hu, Dan | Wang, Xuejun
Understanding of the magnitude of urban runoff toxicity to aquatic organisms is important for effective management of runoff quality. In this paper, the aquatic toxicity of polycyclic aromatic hydrocarbons (PAHs) in urban road runoff was evaluated through a damage assessment model. Mortality probability of the organisms representative in aquatic environment was calculated using the monitored PAHs concentration in road runoff. The result showed that the toxicity of runoff in spring was higher than those in summer. Analysis of the time-dependent toxicity of series of runoff water samples illustrated that the toxicity of runoff water in the final phase of a runoff event may be as high as those in the initial phase. Therefore, the storm runoff treatment systems or strategies designed for capture and treatment of the initial portion of runoff may be inappropriate for control of runoff toxicity.
Show more [+] Less [-]Effects of C₆₀ nanoparticle exposure on earthworms (Lumbricus rubellus) and implications for population dynamics
2011
van der Ploeg, M.J.C. | Baveco, J.M. | van der Hout, A. | Bakker, R. | Rietjens, I.M.C.M. | van den Brink, N.W.
Effects of C₆₀ nanoparticles (nominal concentrations 0, 15.4 and 154mg/kg soil) on mortality, growth and reproduction of Lumbricus rubellus earthworms were assessed. C₆₀ exposure had a significant effect on cocoon production, juvenile growth rate and mortality. These endpoints were used to model effects on the population level. This demonstrated reduced population growth rate with increasing C₆₀ concentrations. Furthermore, a shift in stage structure was shown for C₆₀ exposed populations, i.e. a larger proportion of juveniles. This result implies that the lower juvenile growth rate due to exposure to C₆₀ resulted in a larger proportion of juveniles, despite increased mortality among juveniles. Overall, this study indicates that C₆₀ exposure may seriously affect earthworm populations. Furthermore, it was demonstrated that juveniles were more sensitive to C₆₀ exposure than adults.
Show more [+] Less [-]Arsenic and Mn levels in Isaza (Gymnogobius isaza) during the mass mortality event in Lake Biwa, Japan
2011
Hirata, Sawako Horai | Hayase, Daisuke | Eguchi, Akifumi | Itai, Takaaki | Nomiyama, Kei | Isobe, Tomohiko | Agusa, Tetsuro | Ishikawa, Toshiyuki | Kumagai, Michio | Tanabe, Shinsuke
The present study measured the concentrations of 25 elements (Li, Mg, V, Cr, Mn, Co, Ni, Cu, Zn, As, Se, Rb, Sr, Mo, Ag, Cd, In, Sn, Sb, Cs, Ba, Hg, Tl, Pb and Bi) in the whole body of Isaza which is an endemic fish species to Lake Biwa, Japan, and compared the values in the specimens from the mass mortality Isaza (MMI) and normal fresh Isaza (NFI). The mean levels of Mn and total As (T-As) were relatively higher in MMI than in NFI. In the T-As, highly toxic inorganic As was detected in MMI. Moreover we found Mn and As concentrations in surface sediment were extremely high and temporally increased. From all these results, we could infer that the dissolution of Mn and As from surface sediment of Lake Biwa might have been one of the cause for the mass mortality of Isaza.
Show more [+] Less [-]How to select the best tree planting locations to enhance air pollution removal in the MillionTreesNYC initiative
2011
Morani, Arianna | Nowak, David J. | Hirabayashi, Satoshi | Calfapietra, Carlo
Highest priority zones for tree planting within New York City were selected by using a planting priority index developed combining three main indicators: pollution concentration, population density and low canopy cover. This new tree population was projected through time to estimate potential air quality and carbon benefits. Those trees will likely remove more than 10 000 tons of air pollutants and a maximum of 1500 tons of carbon over the next 100 years given a 4% annual mortality rate. Cumulative carbon storage will be reduced through time as carbon loss through tree mortality outweighs carbon accumulation through tree growth. Model projections are strongly affected by mortality rate whose uncertainties limit estimations accuracy. Increasing mortality rate from 4 to 8% per year produce a significant decrease in the total pollution removal over a 100 year period from 11 000 tons to 3000 tons.
Show more [+] Less [-]Comparative phototoxicity of nanoparticulate and bulk ZnO to a free-living nematode Caenorhabditis elegans: The importance of illumination mode and primary particle size
2011
Ma, H. | Kabengi, N.J. | Bertsch, P.M. | Unrine, J.M. | Glenn, T.C. | Williams, P.L.
The present study evaluated phototoxicity of nanoparticulate ZnO and bulk-ZnO under natural sunlight (NSL) versus ambient artificial laboratory light (AALL) illumination to a free-living nematode Caenorhabditis elegans. Phototoxicity of nano-ZnO and bulk-ZnO was largely dependent on illumination method as 2-h exposure under NSL caused significantly greater mortality in C. elegans than under AALL. This phototoxicity was closely related to photocatalytic reactive oxygen species (ROS) generation by the ZnO particles as indicated by concomitant methylene blue photodegradation. Both materials caused mortality in C. elegans under AALL during 24-h exposure although neither degraded methylene blue, suggesting mechanisms of toxicity other than photocatalytic ROS generation were involved. Particle dissolution of ZnO did not appear to play an important role in the toxicity observed in this study. Nano-ZnO showed greater phototoxicity than bulk-ZnO despite their similar size of aggregates, suggesting primary particle size is more important than aggregate size in determining phototoxicity.
Show more [+] Less [-]The mobilisation of sediment by demersal otter trawls
2011
O’Neill, F.G. | Summerbell, K.
The mobilisation of sediment by towed demersal fishing gears has been related to the release of nutrients, benthic infaunal mortality and the resuspension of phytoplankton cysts and copepod eggs. Hence, to understand the broader environmental and ecological implications of demersal fishing, it is important to be able to estimate accurately the amount of sediment put into the water column by towed gears. Experimental trials were carried out in the Moray Firth, Scotland, to measure the quantity of sediment remobilised by trawl gear components. It is demonstrated, for a given sediment type, that there is a relationship between the hydrodynamic drag of the gear element and the mass of sediment entrained behind it. A better understanding of this relationship and the hydrodynamic processes involved will lead to the development of accurate predictive models and aid the design of fishing gears of reduced impact.
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