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1.
Physical and ecological responses of the coastal areas in the vicinity of Mumbai, India, due to relative sea level rise are examined by different inundation scenarios. Evaluation of potential habitat loss under sea level rise was made by incorporating the land use/land cover (LULC) adopted from the digital elevation model with the satellite imagery. LULC categories overlaid on 1.0, 2.0, 3.0 and 4.0 m coastal elevation showed that the coastal areas of Mumbai were mostly covered by vegetation followed by barren land, agricultural land, urban areas and water bodies. For the relative sea level rise scenarios of 1.0, 2.0, 3.0 and 4.0 m, the tidal inundation areas were estimated to be 257.85, 385.58, 487.56 and 570.63 km2, respectively, using GIS techniques. The losses of urban areas were also estimated at 25.32, 41.64, 54.61 and 78.86 km2 for the 1.0, 2.0, 3.0 and 4.0 m relative sea level rise, respectively, which is most alarming information for the most populated city on the eastern coast of India. The results conclude that relative sea level rise scenario will lead profound impacts on LULC categories as well as on coastal features and landforms in the adjoining part of Mumbai. The sea level rise would also reduce the drainage gradients that promote flooding condition to rainstorms and subsequently increase saltwater intrusion into coastal regions. Alterations in the coastal features and landforms correlated with inundation characteristics that make the coastal region more vulnerable in the coming decades due to huge development activities and population pressures in Mumbai.  相似文献   

2.
The usage of Engineered Nanoparticles (ENPs) in consumer products is relatively new and there is a need to conduct environmental risk assessment (ERA) to evaluate their impacts on the environment. However, alternative approaches are required for ERA of ENPs because of the huge gap in data and knowledge compared to conventional pollutants and their unique properties that make it difficult to apply existing approaches. This study aims to propose an ERA approach for ENPs by integrating Analytical Hierarchy Process (AHP) and fuzzy inference models which provide a systematic evaluation of risk factors and reducing uncertainty about the data and information, respectively. Risk is assumed to be the combination of occurrence likelihood, exposure potential and toxic effects in the environment. A hierarchy was established to evaluate the sub factors of these components. Evaluation was made with fuzzy numbers to reduce uncertainty and incorporate the expert judgements. Overall score of each component was combined with fuzzy inference rules by using expert judgements. Proposed approach reports the risk class and its membership degree such as Minor (0.7). Therefore, results are precise and helpful to determine the risk management strategies. Moreover, priority weights calculated by comparing the risk factors based on their importance for the risk enable users to understand which factor is effective on the risk. Proposed approach was applied for Ag (two nanoparticles with different coating) and TiO2 nanoparticles for different case studies. Results verified the proposed benefits of the approach.  相似文献   

3.
Production volumes and the use of engineered nanomaterials in many innovative products are continuously increasing, however little is known about their potential risk for the environment and human health. We have reviewed publicly available hazard and exposure data for both, the environment and human health and attempted to carry out a basic risk assessment appraisal for four types of nanomaterials: fullerenes, carbon nanotubes, metals, and metal oxides (ENRHES project 2009(1)). This paper presents a summary of the results of the basic environmental and human health risk assessments of these case studies, highlighting the cross cutting issues and conclusions about fate and behaviour, exposure, hazard and methodological considerations. The risk assessment methodology being the basis for our case studies was that of a regulatory risk assessment under REACH (ECHA, 2008(2)), with modifications to adapt to the limited available data. If possible, environmental no-effect concentrations and human no-effect levels were established from relevant studies by applying assessment factors in line with the REACH guidance and compared to available exposure data to discuss possible risks. When the data did not allow a quantitative assessment, the risk was assessed qualitatively, e.g. for the environment by evaluating the information in the literature to describe the potential to enter the environment and to reach the potential ecological targets. Results indicate that the main risk for the environment is expected from metals and metal oxides, especially for algae and Daphnia, due to exposure to both, particles and ions. The main risks for human health may arise from chronic occupational inhalation exposure, especially during the activities of high particle release and uncontrolled exposure. The information on consumer and environmental exposure of humans is too scarce to attempt a quantitative risk characterisation. It is recognised that the currently available database for both, hazard and exposure is limited and there are high uncertainties in any conclusion on a possible risk. The results should therefore not be used for any regulatory decision making. Likewise, it is recognised that the REACH guidance was developed without considering the specific behaviour and the mode of action of nanomaterials and further work in the generation of data but also in the development of methodologies is required.  相似文献   

4.
Polybrominated diphenyl ethers (PBDEs) have previously been detected in children toys, yet the risk of child exposure to these chemicals through the mouthing of toys or other items is still unknown. We aimed to expand on the current knowledge by investigating the impact of infants' mouthing activities on exposure to PBDEs present in toys. This was established by a leaching model for determining the amount PBDEs that can leach from toys into saliva in simulated conditions. The PBDE migration rate was at its highest for the 15 min low-exposure scenario incubations (198 pg/cm2 × min) with the ERM EC-591 certified reference material (CRM) (0.17% w/w PBDEs). The leaching process was congener-dependent, since the percentage of lower brominated PBDE congeners that leached out was up to 4.5 times higher than for the heavier PBDEs. To study the scenario in which a child would mouth on a toy flame retarded with BDE 209 alone, a plastic item containing 7% BDE 209 (w/w) was also tested. The BDE 209 amounts leached out in only 15 min were higher than the amounts leached from the CRM after the 16 h incubation. For the Belgian population, the exposure scenario from mouthing on toys containing PBDEs in amounts similar to the REACH threshold was found to be lower than the exposure from mother's milk, but higher than the exposure through diet or even dust.  相似文献   

5.
Zinc oxide nanoparticles (ZnO NPs) are one of the most abundantly used nanomaterials in consumer products and biomedical applications. As a result, human exposure to these NPs is highly frequent and they have become an issue of concern to public health. Although toxicity of ZnO NPs has been extensively studied and they have been shown to affect many different cell types and animal systems, there is a significant lack of toxicological data for ZnO NPs on the nervous system, especially for human neuronal cells and tissues. In this study, the cytotoxic and genotoxic effects of ZnO NPs on human SHSY5Y neuronal cells were investigated under different exposure conditions. Results obtained by flow cytometry showed that ZnO NPs do not enter the neuronal cells, but their presence in the medium induced cytotoxicity, including viability decrease, apoptosis and cell cycle alterations, and genotoxicity, including micronuclei production, H2AX phosphorylation and DNA damage, both primary and oxidative, on human neuronal cells in a dose- and time-dependent manner. Free Zn2 + ions released from the ZnO NPs were not responsible for the viability decrease, but their role on other types of cell damage cannot be ruled out. The results obtained in this work contribute to increase the knowledge on the genotoxic and cytotoxic potential of ZnO NPs in general, and specifically on human neuronal cells, but further investigations are required to understand the action mechanism underlying the cytotoxic and genotoxic effects observed.  相似文献   

6.
Personal exposure to nitrogen dioxide (NO2) and time spent in various locations were measured for 66 family members from 19 homes in the Portage, WI area during March 1981. Passive diffusion NO2 monitors were placed outdoors, in the kitchen, and in one bedroom on each floor of the homes, and were worn by family members. Individuals from gas-cooking homes had significantly higher average NO2 exposures than those from homes using electricity for cooking (mean difference 19.37 μg/m3). Personal exposures were more closely related to bedroom levels than to kitchen or outdoor concentrations for both cooking fuel groups. Several preliminary models are presented which relate average personal NO2 exposure to indoor and ambient levels, and also to the proportion of time spent in different locations. These models are capable of explaining nearly 90% of the variation about the mean in personal exposure.  相似文献   

7.
The establishment of a global multi-regional carbon market is considered to be a cost effective approach to facilitate global emission abatement and has been widely concerned.The ongoing planned linkage between the European Union’s carbon market and a new emission trading system in Australia in 2015 would be an important attempt to the practice of building up an international carbon market across different regions.To understand the abatement effect of such a global carbon market and to study its energy and economic impact on different market participants,this article adopts a global dynamic computable general equilibrium model with a detailed representation of the interactions between energy and economic systems.Our model includes 20 economic sectors and 19 regions,and describes in detail 17 energy technologies.Bundled with fossil fuel consumptions,the emission permits are considered to be essential inputs in each of the production and consumption activities in the economic system to simulate global carbon market policies.Carbon emission permits are endogenously set in the model,and can be traded between sectors and regions.Considering the current development of the global carbon market,this study takes 2020 as the study period.Four scenarios(reference scenario,independent carbon market scenario,Europe Union(EUh-Australia scenario,and China-EU-Australia scenario) are designed to evaluate the impact of the global carbon market involving China,the EU,and Australia.We find that the carbon price in the three countries varies a lot,from $32/tCO2 in Australia,to $17.5/tCO2 in the EU,and to $10/tCO2 in China.Though the relative emission reduction(3%) in China is lower than that in the EU(9%) and Australia(18%),the absolute emission reduction in China is far greater than that in the EU and Australia.When China is included in the carbon market,which already includes the EU and Australia,the prevailing global carbon price falls from $22 per ton carbon dioxide(CO2) to $12/tCO2,due to the relatively lower abatement cost in China.Seventy-one percent of the EU’s and eighty-one percent of Australia’s domestic reduction burden would be transferred to China,increasing 0.03%of the EU’s and 0.06%of Australia’s welfare.The emission constraint improves the energy efficiency of China’s industry sector by 1.4%,reduces coal consumption by3.3%,and increases clean energy by 3.5%.  相似文献   

8.
Vegetation and climate   总被引:1,自引:0,他引:1  
Over the last two centuries, man's activities have caused a 30% increase in the atmospheric concentration of CO2, with continued increases seeming inevitable. This change in CO2 concentration will act on vegetation, both directly and indirectly through global climatic change. It is well established that, on a global scale, patterns of vegetation and climate are closely correlated. Such correlations indicate that climatic change will cause the distribution of vegetation to change. However, the use of correlations for predicting vegetation responses to climatic change is fundamentally unreliable because correlations have no mechanistic underpinning of causation. This paper outlines a mechanistic model for predicting the equilibrium state between current climate and vegetation. It is also used to indicate the sensitivity of global vegetation to the changed climate associated with a doubled CO2—greenhouse scenario. The interpretation of this static model is discussed in terms of rates and patterns of vegetation change.  相似文献   

9.
Nanotechnology is a major innovative scientific and economic growth area, which may present a variety of hazards for environmental and human health. The surface properties and very small size of nanoparticles and nanotubes provide surfaces that may bind and transport toxic chemical pollutants, as well as possibly being toxic in their own right by generating reactive radicals. There is a wealth of evidence for the harmful effects of nanoscale combustion-derived particulates (ultrafines), which when inhaled can cause a number of pulmonary pathologies in mammals and humans. However, release of manufactured nanoparticles into the aquatic environment is largely an unknown. This review addresses the possible hazards associated with nanomaterials and harmful effects that may result from exposure of aquatic animals to nanoparticles. Possible nanoparticle association with naturally occurring colloids and particles is considered together with how this could affect their bioavailability and uptake into cells and organisms. Uptake by endocytotic routes are identified as probable major mechanisms of entry into cells; potentially leading to various types of toxic cell injury. The higher level consequences for damage to animal health, ecological risk and possible food chain risks for humans are also considered based on known behaviours and toxicities for inhaled and ingested nanoparticles in the terrestrial environment. It is concluded that a precautionary approach is required with individual evaluation of new nanomaterials for risk to the health of the environment. Although current toxicity testing protocols should be generally applicable to identify harmful effects associated with nanoparticles, research into new methods is required to address the special properties of nanomaterials.  相似文献   

10.
11.
A badge-type personal sampler was developed for measuring personal exposure to nitrogen dioxide (NO2). An absorbent sheet containing triethanolamine (TEA) solution absorbed NO2 which diffused through five layers of hydrophobic fiber filter. Wind effects on absorption rate were suppressed by these filter layers. NO2 was measured by the sampler with a sensitivity of 124.8 μg h/m3 (66 ppb h) and an accuracy of within ± 20%. It could be used for measuring personal exposure to NO2 without interfering with the wearer's daily activities. Nitric oxide (NO) could be measured after a small modification to the sampler provided oxidation ability to the layers of diffusion filter. Three layers of hydrophobic fiber filter were replaced by 12 layers of glass fiber filter containing chromium trioxide solution. NO was oxidized to NO2 in the oxidation layers and absorbed by the absorbent sheet together with the coexisting NO2. Sensitivity and accuracy of the sampler for NO were nearly equal to that for NO2.  相似文献   

12.
In the context of assessing potential risks of engineered nanoparticles (ENPs), life cycle thinking can represent a holistic view on the impacts of ENPs through the entire value chain of nano-enhanced products from production, through use, and finally to disposal. Exposure to ENPs in consumer or environmental settings may either be to the original, pristine ENPs, or more likely, to ENPs that have been incorporated into products, released, aged and transformed. Here, key product-use related aging and transformation processes affecting ENPs are reviewed. The focus is on processes resulting in ENP release and on the transformation(s) the released particles undergo in the use and disposal phases of its product life cycle for several nanomaterials (Ag, ZnO, TiO2, carbon nanotubes, CeO2, SiO2 etc.). These include photochemical transformations, oxidation and reduction, dissolution, precipitation, adsorption and desorption, combustion, abrasion and biotransformation, among other biogeochemical processes. To date, few studies have tried to establish what changes the ENPs undergo when they are incorporated into, and released from, products. As a result there is major uncertainty as to the state of many ENPs following their release because much of current testing on pristine ENPs may not be fully relevant for risk assessment purposes. The goal of this present review is therefore to use knowledge on the life cycle of nano-products to derive possible transformations common ENPs in nano-products may undergo based on how these products will be used by the consumer and eventually discarded. By determining specific gaps in knowledge of the ENP transformation process, this approach should prove useful in narrowing the number of physical experiments that need to be conducted and illuminate where more focused effort can be placed.  相似文献   

13.
This paper deals with the physico-chemical behaviour of neptunium in sea water and with its capacity for transfer to coastal or deep-sea sediments and for uptake by two benthic species, Arenicola marina (L.) and Cerastoderma edule (L.). We used the 239Np isotope with mass concentrations in sea water of about 2·5 × 10−10−5·4×10−12 g litre−1, which are close to the concentrations observed in the environment for 237Np. The experimental results show that Np occurs in solution mainly as the neptunyl ion NpO2+, but soluble anionic and neutral complexes and particulate forms were also detected. The distribution coefficients for the sediments varied from 350 to 6500. The carbonate phase plays a decisive role in neptunium transfer but other fixation processes are also possible. Concentration factors after 13 days were found to have values of 40 and 14 for the shells and soft parts of cockles, respectively, while polychaetes had a concentration factor of 2. Thus Np has a smaller probability of transfer to sediments and organisms than have plutonium and americium.  相似文献   

14.
Bottled water consumption is a putative source of human exposure to endocrine-disrupting chemicals (EDCs). Research has been conducted on the presence of chemicals with estrogen-like activity in bottled waters and on their estrogenicity, but few data are available on the presence of hormonal activities associated with other nuclear receptors (NRs). The aim of this study was to determine the presence of endocrine activities dependent on the activation of human estrogen receptor alpha (hERa) and/or androgen receptor (hAR) in water in glass or plastic bottles sold to consumers in Southern Spain. Hormone-like activities were evaluated in 29 bottled waters using receptor-specific bioassays based on reporter gene expression in PALM cells [(anti-)androgenicity] and cell proliferation assessment in MCF-7 cells [(anti-)estrogenicity] after optimized solid phase extraction (SPE). All of the water samples analyzed showed hormonal activity. This was estrogenic in 79.3% and anti-estrogenic in 37.9% of samples and was androgenic in 27.5% and anti-androgenic in 41.3%, with mean concentrations per liter of 0.113 pM 17β-estradiol (E2) equivalent units (E2Eq), 11.01 pM anti-estrogen (ICI 182780) equivalent units (ICI 182780Eq), 0.33 pM methyltrienolone (R1881) equivalent units (R1881Eq), and 0.18 nM procymidone equivalent units (ProcEq). Bottled water consumption contributes to EDC exposure. Hormone-like activities observed in waters from both plastic and glass bottles suggest that plastic packaging is not the sole source of contamination and that the source of the water and bottling process may play a role, among other factors. Further research is warranted on the cumulative effects of long-term exposure to low doses of EDCs.  相似文献   

15.
BackgroundThe concentrations of ozone (O3) in China are increasing, especially in East China, but its future trends and potential health impacts remain to be explored.ObjectivesThe objective was to assess future trends in O3 concentrations and related premature death in East China between 2005 and 2030.MethodsFirst, a global chemical transport model (MIROC-ESM-CHEM) and regional chemical transport modelling system (including the Weather Research and Forecasting model and the Community Multiscale Air Quality model) were combined to estimate daily O3 concentrations in 2005 and 2030 in East China under the “current legislation” (CLE) and “maximum technically feasible reduction” (MFR) scenarios which were applied globally. O3 concentrations were then linked with population projections, mortality projections, and O3-mortality associations to estimate changes in O3-related mortality in East China.ResultsThe annual mean O3 concentration was projected to increase in East China between 2005 and 2030 under the CLE scenario, while decrease under the MFR scenario. Under the CLE scenario, O3-attributable health burden could increase by at least 40,000 premature deaths in East China, without considering the population growth. Under the MFR scenario, the health burden could decrease by up to 260,000 premature deaths as a result of the reduction in O3 concentration with a static population. However, when the population growth was considered, O3-attributable health burden could increase by up to 46,000 premature deaths in East China under the MFR scenario.ConclusionsThe results suggest that the health burden attributable to O3 may increase in East China in 2030.  相似文献   

16.
The influence of long-term exposure of model plantations at elevated atmospheric CO2 (550 ppm) on soil respiration under natural conditions has been studied using an automated Free-Air CO2 Enrichment (FACE) system at the Hokkaido University, Japan. In the course of the experiment, an attempt has been made to simulate the effect of forthcoming climate change on the process of CO2 emission from different soil types.  相似文献   

17.
Ecological risk of chemicals is measured by the quotient of predicted no-effect concentrations and predicted exposure concentrations, which are hard to assess for manufactured nanomaterials (NMs). This paper proposes modifications to currently used models, in order to make them suitable for estimating exposure concentrations of NMs in the aquatic environment. We have evaluated the adequacy of the current guidance documents for use with NMs and conclude that nano-specific fate processes, such as sedimentation and dissolution need to be incorporated. We have reviewed the literature on sedimentation and dissolution of NMs in environmentally relevant systems. We deduce that the overall kinetics of water-sediment transport of NMs should be close to first order. The lack of data on dissolution of NMs under environmentally realistic conditions calls for a pragmatic decision on which rates to be used in modeling. We find that first order removal kinetics for dissolution seems adequate. Based on limited data from literature, probable removal rates range from 0 to 10(-4)s(-1) for sedimentation, and from 0 to 10(-5)s(-1) for dissolution. Further experimental data at environmentally relevant conditions for sedimentation and dissolution of NMs is needed.  相似文献   

18.
Exposure to sidestream tobacco smoke is concerned with constituents in suspension in the indoor atmosphere. The natural dissipation of sidestream tobacco smoke has been investigated in a static atmosphere in a 10 m3 experimental chamber, and the rate of dissipation is expressed as T0.5, the half-life of residence in the air. Respective T0.5 of smoke components are calculated from the various sample data points, assuming a kinetic equation of the first-order process. Sidestream smoke has been generated by a smoking machine according to the Coresta standard protocol and then left to age over an 8-hour period, with subsequent sampling at defined time intervals. The experiments have been repeated over five days, and eight data point samples are obtained for each experiment. Besides nicotine, CO, and smoke particulate matter, interest has been focused on polycyclic aromatic hydrocarbons (PAH). The initial concentrations, C0 for smoke particulate matter and nicotine (gas and particulate phases) are found to be 13.8 mg and 92 μg per cigarette per cubic meter, with T0.5 being 2.6 and 2.1 hours, respectively. Low molecular-weight PAH have T0.5 up to 20 hours, explainable only by their high concentrations in the gas phase, while the 3- to 7-ring PAH have T0.5 of about 2 hours. The contribution of CO to ambient concentration is 91 mg per cigarette per cubic meter. The data can be useful in mathematical modellization studies regarding ventilation or exposure to sidestream smoke.  相似文献   

19.
NEWS     
Abstract

Co-integration theory has been employed in this paper and Granger causes are found between urbanization rate and GDP, between capital stock and GDP. Scenario analysis of GDP is performed using the GDP model established in the paper. The energy consumptions in Germany, Japan and other developed countries are analyzed and compared with the energy consumption in China. Environmental friendly scenario of energy demand and CO2 emissions for sustainable China has been formed based on the results of comparison. Under environmental friendly scenario, the primary energy consumption will be 4.31 billion ton coal equivalence (tce) and CO2 emissions will be 1.854 billion t-c in 2050; energy per capital will be 3.06 tce that is 1.8 times of energy consumed in 2005 in China and 51% of consumed energy per capital in Japan in 2003. In 2050, the energy requirement of unit GDP will be 20% lower than that of Germany in 2003, but will be still 37% higher than that in Japan in 2003. It is certain that to fulfill the environmental friendly Scenario of energy demand and CO2 emissions is a difficult task and it needs long term efforts of the whole society, not only in production sectors but also in service and household sectors.  相似文献   

20.
This study has attempted to estimate the energy consumption and emission of pollutants namely carbon dioxide (CO2), carbon monoxide (CO), nitrogen oxides (NOx) and non-methane volatile organic compounds (NMVOC) from the road transport sector in Malaysia from the year 2012 till 2040. This was done using the long-range energy alternatives planning (LEAP) model. Estimates of energy consumption and emissions were evaluated and analysed under a business-as-usual scenario and three other alternative fuel policy scenarios of biodiesel vehicles (BIO), natural gas vehicles (NGV) and hybrid electric vehicles (HEV). The aim of this study has been to identify the potential alternative fuel policies that would be effective in reducing the future growth of road transport energy consumption and emission in Malaysia. Results indicate that the NGV scenario contributes towards the highest reduction in road transport energy consumption followed by BIO and HEV. The NGV scenario also achieves highest mitigation of emission of all the four pollutants. In the case of CO2 emission, BIO scenario attains second highest mitigation, whereas in the event of CO, NOx and NMVOC emission, HEV scenario achieves second highest mitigation.  相似文献   

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