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831.
In this study, the relationship between inhalable particulate (PM10), fine particulate (PM2.5), coarse particles (PM2.5 – 10) and meteorological parameters such as temperature, relative humidity, solar radiation, wind speed were statistically analyzed and modelled for urban area of Kolkata during winter months of 2003–2004. Ambient air quality was monitored with a sampling frequency of twenty-four hours at three monitoring sites located near traffic intersections and in an industrial area. The monitoring sites were located 3–5 m above ground near highly trafficked and congested areas. The 24 h average PM10 and PM2.5 samples were collected using Thermo-Andersen high volume samplers and exposed filter papers were extracted and analysed for benzene soluble organic fraction. The ratios between PM2.5 and PM10 were found to be in the range of 0.6 to 0.92 and the highest ratio was found in the most polluted urban site. Statistical analysis has shown a strong positive correlation between PM10 and PM2.5 and inverse correlation was observed between particulate matter (PM10 and PM2.5) and wind speed. Statistical analysis of air quality data shows that PM10 and PM2.5 are showing poor correlation with temperature, relative humidity and solar radiation. Regression equations for PM10 and PM2.5 and meteorological parameters were developed. The organic fraction of particulate matter soluble in benzene is an indication of poly aromatic hydrocarbon (PAH) concentration present in particulate matter. The relationship between the benzene soluble organic fraction (BSOF) of inhalable particulate (PM10) and fine particulate (PM2.5) were analysed for urban area of Kolkata. Significant positive correlation was observed between benzene soluble organic fraction of PM10 (BSM10) and benzene soluble organic fraction of PM2.5 (BSM2.5). Regression equations for BSM10 and BSM2.5 were developed. 相似文献
832.
Obiri S Dodoo DK Okai-Sam F Essumang DK Adjorlolo-Gasokpoh A 《Environmental monitoring and assessment》2006,118(1-3):37-49
Food crops such as cassava, cocoyam and other tuber crops grown in mining communities uptake toxic or hazardous chemicals
such as arsenic, and cadmium, from the soil. Cassava is a stable food for Ghanaians. This study evaluated human health risk
from eating cassava grown in some mining communities in Ghana such as Bogoso, Prestea, Tarkwa and Tamso, which are important
mining towns in the Western Region of Ghana. The study evaluated cancer and non-cancer health effects from eating cassava
grown in the study areas in accordance with US Environmental Protection Agency’s Risk Assessment guidelines. The results of
the study revealed the following: cancer health risk for Tamso, 0.098 (RME – Reasonable Maximum Exposure) and 0.082 (CTE –
Central Tendency Exposure). This means that approximately 10 and 8 out of 100 resident adults are likely to suffer from cancer
related cases by RME and CTE parameters respectively. For Prestea, we have 0.010 and 0.12, which also means that approximately
1 out of 100 and 10 resident adults out of 100 are also likely to suffer from cancer related diseases by RME and CTE parameters.
The results of the study obtained were found to be above the acceptable cancer risk range of 1× 10−6 to 1× 10−4, i.e., 1 case of cancer out of 1 million or 100,000 people respectively. 相似文献
833.
Dissipation behaviour of endosulfan and dichlorvos in/on cauliflower, variety Snowball-16, was studied during rabi season
(Sep.–March) 2003–2004. Endosulfan and dichlorvos were sprayed @ 350 and 110g a.i. with 115 g a.i., respectively, 80 days
after transplanting. Samples were taken at the interval of 0 (1h after spray), 3, 5, 7, and 10 days after spray (DAS) in triplicate
and residues were estimated on GC-ECD system equipped with capillary column. The initial deposits of 3.452 and 0.295μgg−1 of endosulfan and dichlorvos dissipated to 0.084 (97.56%) and 0.009 (96.95%), respectively after 10 DAS. Residues of endosulfan
reached below maximum residue limit of 2μgg−1 one day after spray and of dichlorvos were below MRL value of 0.5μgg−1 even on 0 day. Dissipation pattern followed first order kinetics for both the insecticides with half life periods of 1.81
and 2.08 days for endosulfan and dichlorvos, respectively. 相似文献
834.
Kim KH Mishra VK Kang CH Choi KC Kim YJ Kim DS Youn YH Lee JH 《Environmental monitoring and assessment》2006,121(1-3):379-397
In the present study, the distribution patterns of various metals were analyzed and compared using PM samples collected concurrently from three monitoring sites located in Korea (Seoul, Busan, and Jeju island) in December 2002. As these sites can represent metal pollution with different degrees of anthropogenic activities, their concentration levels were distinguished in a systematic manner in the order of Jeju, Busan, and Seoul. By comparing the present data sets with those measured previously from other locations in Korea and around the world, we attempted to diagnose the general status of elemental pollution on the Korean peninsula. Through an application of different statistical approaches, the major processes controlling elemental levels were assessed for each of the three study sites. The results indicated the importance of both crustal and anthropogenic sources in all sites with their relative roles varying significantly from each other. The results of the metal analysis data, when examined in relation to back trajectory analysis, confirmed that their concentration changes are affected quite sensitively with air mass movement patterns. The overall results of this study consistently indicated the contribution of a strong anthropogenic source area (e.g., China) to the observed metal concentration levels in the study area, but the strengths of such signals vary considerably across the Korean peninsula. 相似文献
835.
The Atlantic Coastal Action Program (ACAP) is a unique, community-based program initiated by Environment Canada in 1991 to help Atlantic Canadians restore and sustain watersheds and adjacent coastal areas. ACAP is the eastem-most Environment Canada Ecosystem Initiative. The ACAP family is currently made up of 14 ecosystem-based organizations in the four Atlantic provinces. Each one of these non-profit organizations operates independently, but is formally linked under the umbrella of ACAP to represent a force stronger than the individual parts. In Environment Canada's experience, the program consistently demonstrates the value of a community-based approach and produces results on an ecosystem basis. This paper will examine some of the impacts of ACAP in terms of economics, credible community science, and environmental results which most often align with Environment Canada's objectives. It will explore the influences of the community-based approach to environmental management on multiple scales (local, regional, etc.). Through examples, the paper will demonstrate the effectiveness of ACAP in influencing some of the policies, programs and attitudes of various levels of government and industry in the region, as well as describe how the community-based model has been exported internationally. The paper will conclude with a discussion on a planned path forward for ACAP. 相似文献
836.
Steroid estrogens such as estrone (E1), 17β-estradiol (E2), estriol (E3), and 17α-ethynylestradiol (EE2) have been suspected to be the main contaminants, which can affect the endocrine system of animals. Many authors have investigated these chemicals in the domestic wastewater treatment plants (WTP). However, wastewater from industries producing steroid contraceptives has not got ample attention. From the environmental point of view, the four steroids are very significant because even very low concentrations (ng/L) can cause reproductive disturbances in human, livestock and wildlife. The main purpose of the present investigation was to develop an analytical method for the determination of the four steroid estrogens present in WTP of a pharmacy factory, mainly producing contraceptive medicine in Beijing, China. Analysis was performed by solid-phase extraction (SPE) system and liquid chromatography combined with tandem mass spectrometry (LC/MS/MS). The average recoveries from effluent samples ranged from 88% to 103% and the precision of the method ranged from 9% to 4%. Based on 0.5-L wastewater samples, the limit of quantification (LOQ) was determined at 0.7 ng/L for E1, 0.8 for E2, 0.9 ng/L for E3, and 0.5 ng/L for EE2 in influent, and 1.0 ng/L for E2 and EE2, and 2.0 ng/L for E1 and E3 in effluent. In the influent samples, average concentrations of 80, 85, 73 and 155 ng/L were determined for E1, E2, E3 and EE2, respectively, showing that they were removed in this WTP to the extent of 79, 73, 85 and 67%, respectively. 相似文献
837.
To investigate the effect of temperature on effective diffusion coefficients and retardation factors for Zn and Cd, combined
diffusion and sequential extraction analyses were conducted at 15 ˚C and 55 ˚C. The effective diffusion coefficients of the metals increased up to ten times according to the increased temperature. On
the other hand, the effect of temperature on the retardation factor depended on the retention mechanisms of the metals. The
distribution coefficient for Zn, which was mainly partitioned in the carbonate phase, increased up to two times with the increase
in temperature. On the other hand, the distribution coefficient for Cd, which was mainly partitioned in the exchangeable phase,
was hardly affected by the temperature change. Results of combined diffusion and sequential extraction analysis showed that
the effect of temperature on the heavy metals’ (Zn and Cd) migration through the compacted natural clay was influenced by
the combined effects of the diffusion coefficient and the retardation factor. Additionally, we could also observe the change
in retention mechanism for the metals with the change in pore water concentration. 相似文献
838.
839.
840.
基于FHWA的兰州市道路交通噪声预测模型的建立 总被引:4,自引:0,他引:4
结合美国道路交通噪声污染预测模型(FHWA)和国内学者在该方面的大量研究成果,选择兰州市主、次干道共计52条、142个监测点的建模采样数据,并应用统计学原理分析了影响道路交通噪声的各个因子与道路交通噪声的相关性,最终得出了符合兰州市道路交通特征的噪声污染统计预测模型.随后通过兰州市15个监测点的预测与实测对比验证后发现二者具有较高的一致性,此模型可应用在兰州市道路交通噪声污染的预测评价中. 相似文献