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1.
High population growth and continued economic development have caused serious environmental damage in the Asia Pacific region.However,the recent experience is that the pace of environmental degradation is faster in developing countries than in developed countries.To this end,the study seeks to assess the impact of population pressure on India’s environment,with particular reference to the degradation of natural endowments like land and water resources and the resultant environmental pollution in the six regions of India.The rapid economic growth and expansion of infrastructure development in recent decades have not come without serious environmental consequences particularly in the southern,northern,and western regions.But in the eastern,north-eastern,and central regions of the country,environmental damage has been mainly due to rapid population growth.  相似文献   

2.
Caesium (137Cs and 134Cs) concentrations in higher fungi (Basidiomycetes) from Slovenia, north-west Yugoslavia, are reported following the Chernobyl accident. Special attention was paid to the Cortinariaceae, already known as Cs accumulators. The highest levels were found in Cortinarius armillatus, C. traganus (both inedible species) and Rozites caperata. The median concentration of 137,134Cs in R. caperata from over 40 sampling sites was about 22 kBq/kg dry weight. High levels were also found in Xerocomus badius and Laccaria amethystina.From the 137Cs/134Cs ratios, which reflect the depth of the mycelium and the excess 137Cs from historic pre-Chernobyl fallout, it may be surmised that radiocaesium levels in certain species will probably increase further next year and subsequently as Cs migrates down the soil profile.In addition, 110mAg was found at concentrations up to 500 Bq/kg dry weight in certain species known to be Ag accumulators, particularly Agaricaceae and Lycoperdaceae.  相似文献   

3.
Regional Environmental Change - Wildfire poses a rising threat in the western USA, fueled by synergies between historical fire suppression, changing land use, insects and disease, and shifts toward...  相似文献   

4.
Children's blood-lead concentration (B-Pb) is well studied, but little is known about cadmium (B-Cd) and mercury (B-Hg), in particular for central Europe. Such information is necessary for risk assessment and management. Therefore, we here describe and compare B-Pb, B-Cd and B-Hg in children in six European, and three non-European cities, and identify determinants of these exposures. About 50 school children (7–14 years) from each city were recruited (totally 433) in 2007–2008. Interview and questionnaire data were obtained. A blood sample was analyzed: only two laboratories with strict quality control were used. The European cities showed only minor differences for B-Cd (geometric means 0.11–0.17 μg/L) and B-Pb (14–20 μg/L), but larger for B-Hg (0.12–0.94 μg/L). Corresponding means for the non-European countries were 0.21–0.26, 32–71, and 0.3–3.2 μg/L, respectively. For B-Cd in European samples, traffic intensity close to home was a statistically significant determinant, for B-Hg fish consumption and amalgam fillings, and for B-Pb sex (boys higher). This study shows that European city children's B-Cd and B-Pb vary only little between countries; B-Hg differs considerably, due to varying tooth restoration practices and fish intake. Traffic intensity seemed to be a determinant for B-Cd. The metal concentrations were low from a risk perspective but the chosen non-European cities showed higher concentrations than the cities in Europe.  相似文献   

5.
Formaldehyde, an economically important chemical, is classified as a human carcinogen that causes nasopharyngeal cancer and probably leukemia. As China is the largest producer and consumer of formaldehyde in the world, the Chinese population is potentially at increased risk for cancer and other associated health effects. In this paper we review formaldehyde production, consumption, exposure, and health effects in China. We collected and analyzed over 200 Chinese and English documents from scientific journals, selected newspapers, government publications, and websites pertaining to formaldehyde and its subsequent health effects.Over the last 20 years, China's formaldehyde industry has experienced unprecedented growth, and now produces and consumes one-third of the world's formaldehyde. More than 65% of the Chinese formaldehyde output is used to produce resins mainly found in wood products — the major source of indoor pollution in China. Although the Chinese government has issued a series of standards to regulate formaldehyde exposure, concentrations in homes, office buildings, workshops, public places, and food often exceed the national standards. In addition, there have been numerous reports of formaldehyde-induced health problems, including poisoning and cancer. The lack of quality epidemiological studies and basic data on exposed populations emphasizes the need for more extensive studies on formaldehyde and its related health effects in China.  相似文献   

6.
222Rn, 226Ra, 228Ra and U were determined in a total of 552 groundwater samples collected throughout Fujian Province of China. The geometric mean concentrations of 222Rn, 226Ra, 228Ra and total U in the groundwater were 147.8 kBq m-3, 12.7 Bq m-3, 30.2 Bq m-3 and 0.54 microgram kg-1, respectively. High groundwater 222Rn was explained by the predominantly granitic rock aquifers in Fujian. A lifetime risk of 1.7 x 10(-3) was estimated for the ingestion of groundwater 222Rn. High ratios of 228Ra to 226Ra contents (geometric mean of 2.4) and their disproportion suggest that 228Ra should also be measured in the assessment of population doses from drinking water in the regions of high rock or soil 232Th. No significant correlation between the 222Rn concentrations in groundwater and air was found.  相似文献   

7.
Farming in higher latitudes is generally believed to benefit from a warmer climate due to extended growing season, reduced risk of frost, availability of more productive cultivars, and an opening potential of farming in northern locations. We analyzed the impact of climate change on production of cereals in Russia and found that this general perception of beneficiary effect of a warmer climate is unlikely to hold, primarily due to increasing risk of droughts in the most important agricultural areas of the country. Past impacts of droughts on food security throughout the twentieth century suggest that a number of adaptation options are available to mitigate the increasing risks of crop failure. We analyze the effectiveness of these measures in connection with a set of climate change projections, under two contrasting scenarios of interregional grain trade: “Fortress Market” and “Open Market.”  相似文献   

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9.
Freshwater mussels, Velesunio angasi, along Magela Creek in Australia’s Northern Territory were examined to study radionuclide activities in mussel flesh and to investigate whether the Ranger Uranium mine is contributing to the radium loads in mussels downstream of the mine. Radium loads in mussels of the same age were highest in Bowerbird Billabong, located 20 km upstream of the mine site. Variations in the ratio of [Ra]:[Ca] in filtered water at the sampling sites accounted for the variations found in mussel radium loads with natural increases in calcium (Ca) in surface waters in a downstream gradient along the Magela Creek catchment gradually reducing radium uptake in mussels. At Mudginberri Billabong, 12 km downstream of the mine, concentration factors for radium have not significantly changed over the past 25 years since the mine commenced operations and this, coupled with a gradual decrease of the 228Ra/226Ra activity ratios observed along the catchment, indicates that the 226Ra accumulated in mussels is of natural rather than mine origin. The 228Th/228Ra ratio has been used to model radium uptake and a radium biological half-life in mussels of approximately 13 years has been determined. The long biological half-life and the low Ca concentrations in the water account for the high radium concentration factor of 30,000-60,000 measured in mussels from the Magela Creek catchment.  相似文献   

10.
BackgroundThere is very limited information on the association between arsenic and serum uric acid levels or gout. The aim of this study was to investigate the association of arsenic with hyperuricemia and gout in US adults.MethodsA cross-sectional study was conducted in 5632 adults aged 20 years or older from the National Health and Nutrition Examination Survey (NHANES) 2003–2010 with determinations of serum uric acid and urine total arsenic and dimethylarsinate (DMA). Hyperuricemia was defined as serum uric acid higher than 7.0 mg/dL for men and 6.0 mg/dL for women. Gout was defined based on self-reported physician diagnosis and medication use.ResultsAfter adjustment for sociodemographic factors, comorbidities and arsenobetaine levels, the increase in the geometric means of serum uric acid associated with one interquartile range increase in total arsenic and DMA levels was 3% (95% CI 2–5) and 3% (2–5), respectively, in men and 1% (0–3) and 2% (0–4), respectively, in women. In men, the adjusted odds ratio for hyperuricemia comparing the highest to lowest quartiles of total arsenic was 1.84 (95% CI, 1.26–2.68) and for DMA it was 1.41 (95% CI, 1.01–1.96). The corresponding odds ratios in women were 1.26 (0.77, 2.07) and 1.49 (0.96, 2.31), respectively. The odds ratio for gout comparing the highest to lowest tertiles was 5.46 (95% CI, 1.70–17.6) for total arsenic and 1.98 (0.64–6.15) for DMA among women older than 40 years old. Urine arsenic was not associated with gout in men.ConclusionLow level arsenic exposures may be associated with the risk of hyperuricemia in men and with the prevalence of gout in women. Prospective research focusing on establishing the direction of the relationship among arsenic, hyperuricemia, and gout is needed.  相似文献   

11.
A soil profile from 0 to 90 cm was collected in an undisturbeded area of Cape Cod, Massachusetts. Five centimeter increments of the profile were analyzed for 234,238U, 226Ra, 210Pb and 210Po. The factors affecting the activity distribution of these naturally-occurring radionuclides are discussed for this particular soil type.  相似文献   

12.
Wastewater has proved to be a significant source of polybrominated diphenyl ethers (PBDEs) in the environment. Seventeen congeners from tri- to deca-BDEs were determined to characterize the occurrence, fate, and transport of PBDEs in two sewage treatment plants in the Pearl River Delta, South China. The PBDE concentrations varied substantially from 13.3 to 2496.4 ng L(-1) in the raw wastewater, depending on the wastewater types and contents of the suspended particulate matter (SPM). The concentrations declined to 0.9 to 4.4 ng L(-1) in the treated effluent and were closely associated with SPM contents. BDE-209 was the predominant congener in the wastewater and sewage sludge. Most of PBDEs might have ended up in the sewage sludge, with <4.7% being discharged with the treated effluent. The results revealed that PBDEs were not significantly degraded by biological treatment and chlorination in the STPs. An annual release of PBDEs was estimated at 2280 kg/year through wastewater from the Pearl River Delta.  相似文献   

13.
A quantitative study was conducted in 1998 to investigate differences in perception, knowledge, awareness, and attitude with regard to environmental problems between educated and community groups and to identify human-dimension factors to improve public perception, knowledge, awareness, and attitude in relation to global environmental conservation concerns in developing countries. Educated and community groups in Jakarta were interviewed, and data obtained from a total of 537 males aged 30-49 years were analyzed. The data were evaluated by the chi-squared test and logistic regression was applied after factor analysis. The results show that: (1) The perception, knowledge, awareness, and attitude of educated subjects in regard to regional and global environmental problems were much better than those of subjects in the community group; (2) The highest 'yes' response in the community group was in regard to perception of AIDS (82.9%). Few subjects in the community group knew the effects and the cause or source of environmental problems, however, they were well informed about AIDS (86.4% for effects and 93.9% for cause or source). The conclusions are: (1) subjects in the educated group had better perception, more detailed knowledge, were more aware, and had better attitudes in regard to regional and global environmental problems than those in the community group; (2) more education is needed to develop environmental actions and ethics in developing countries; (3) non-formal environmental education through popular mass media should be used more widely and frequently, and more detailed information on the environment should be provided to literate people by newspapers and other means.  相似文献   

14.
On February 12-15, 2001, more than 200 scientists, engineers, decision makers, and educators participated in a conference on the "Future Directions in Air Quality Research: Ecological, Atmospheric, Regulatory/Policy, and Educational Issues." Important perspectives are summarized from the keynote addresses of noted scientists and educators, as well as managers in government, industry, and public interest groups. Observations and recommendations are provided to stimulate further thought about how to increase opportunities to make greater use of scientific knowledge in air-quality decision making and to ensure that decisions are effective, economically viable, health and ecologically sound, and socially acceptable. Recommendations are given regarding ways in which communications between scientists and policy makers should be structured so as to make appropriate and effective use of scientists and the knowledge they can provide in policy-making fora.  相似文献   

15.
Air pollution is a major environmental problem in urban areas worldwide. Delhi, the capital city of India, is no exception to the universal pattern of deteriorating urban air quality with concentration of pollutants being well above the recommended WHO levels. The magnitude and urgency of the problem as a global environmental issue needs a systematic understanding of the potential causes of pollution and their contribution to air quality. In the present study, ambient air quality data (1987–2006) of SO2, NO2, SPM, and RSPM were analyzed to asses the changing air quality in the study area and to evaluate the effect of measures taken to control it. The primary data were collected from 1,583 households to examine the relationship between outdoor and indoor pollution level. Based on the data, the current study concludes that despite the implementation of different pollution-controlling measures, the pollutants, especially the particulate pollutants, were well above the standard limits set by CPCB. Integration between technological and social approach of urban planning is required to mitigate and manage urban environmental problems in sustainable manner.  相似文献   

16.
Sub-Saharan Africa is particularly vulnerable to climate change. Multiple biophysical, political, and socioeconomic stresses interact to increase the region’s susceptibility and constrain its adaptive capacity. Climate change is commonly recognized as a major issue likely to have negative consequences on food security and livelihoods in the region. This paper reviews three bodies of scholarship that have evolved somewhat separately, yet are inherently interconnected: climate change impacts, vulnerability and adaptation, food security, and sustainable livelihoods. The paper develops a conceptualization of the relationships among the three themes and shows how food security’s vulnerabilities are related to multiple stresses and adaptive capacities, reflecting access to assets. Food security represents one of several livelihood outcomes. The framework shows how several research paradigms relate to the issue of food security and climate change and provides a guide for empirical investigations. Recognizing these interconnections can help in the development of more effective policies and programs. The framework is applied here to synthesize findings from an array of studies in sub-Saharan Africa dealing with vulnerability to climate change, food security, and livelihoods.  相似文献   

17.
Significantly elevated radon concentrations were found in several adjacent houses in Clinton, New Jersey. The United States Environmental Protection Agency screened 56 of the houses and selected 10 for demonstration of radon-reduction techniques. Each of the 10 houses received an intensive radon diagnostic evaluation before a house-specific radon reduction plan was developed. Depressurization effects caused by temperature differentials and the operation of mechanical equipment were quantified. Before and after radon reduction plans were implemented, radon concentrations were determined by charcoal canisters and continuous radon monitors. A variety of sealing and subslab depressurization techniques were applied to the 10 houses. Radon concentrations were reduced by over 95% in all 10 houses. The cost of applying radon reduction techniques ranged from $1500 to $8500 per house. House construction characteristics were described which contributed to the high cost of radon reduction. In summary, the 10-house radon reduction demonstration in Clinton, New Jersey was successful in showing homeowners with similar house types some effective ways of reducing radon concentrations.  相似文献   

18.
The aims were to identify sustainable development priorities and perceived responsibility of sustainable development issues. Differences in opinions between politicians, officials, environmental representatives and the public in four Swedish municipalities were analysed. Sustainable development issues were perceived as more important on the global level than on the municipal and family levels. Among the most important issues on both the global and family levels were clean air, fresh water, and health, whereas decision-making, co-operation, and participation were considered most important on the municipal level. The highest responsibility for sustainable development issues was placed on governments and global organizations and the lowest on the individual. The public felt less individual responsibility and less possibility to influence than did the other groups. The correlation between importance and responsible on municipal and world levels was high but low on the individual level. The responsibility for the most important issue on the family level (clean air) was placed on governments and global organizations. An attitude change is needed to increase responsibility for issues ranked low on individual responsibility. To further raise the awareness of global sustainable development issues, an increased concentration on locally based international co-operation projects is suggested.  相似文献   

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20.
A technique for the isolation of thorium (Th), plutonium (Pu), americium (Am), uranium (U) and strontium (Sr) isotopes from various environmental matrices has been adapted from a previously published method specific to water samples (Maxwell, 2006). Separation and isolation of the various elemental fractions from a single sub-sample is possible, thereby eliminating the need for multiple analyses.The technique involves sample dissolution, concentration via calcium phosphate co-precipitation, rapid column extraction using TEVA™, TRU™ and Sr-Spec™ resin cartridges, alpha spectrometry for Th, Pu, U and Am and Cerenkov counting for Sr.Various standard reference materials were analysed and chemical yields are in the range of 70-80% for Th, Am, U and Sr and 50-60% for Pu. Sample sizes of up to 10 L for water, 5 g for dry soil and sediment and 10 g for dry vegetation and seaweed can be processed using this technique.  相似文献   

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