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1.
Due to papulation increase in Pakistan the demand of drinking water increased day by day. After the industrial grooming the wastewater producing harmful effect on the surrounding area of industries and drinking water contamination increased. Pakistan is on 82 amongst the 125 countries of the word having drinking water problem. Different parameter set by World Health Organization (WHO) and Pakistan Environmental Protection Agency (Pak-EPA) of hazard dimension index (HD) and Lifetime Cancerogenic risk Calculation (LFCR) of Potentially toxic metals that are As, Cd, Cr, Ni, Pb (PTMs) are higher, and the school age children are under high risk of cancer. All the drinking constraints set by regulating authority is fully neglected by inopportune human process by solid waste dumping and houses and industrial disposal with any proper treatment. This study discusses all the HD and LFCR parameter in three age group children, male and female through drinking water around the Hattar Industrial Estate (HIE) in Pakistan. In children and women more HD and LFCR thread than the adult man. The overall result shows that the HD risk is higher than the LFCR due to the PTMs in drinking water only HD is exceed from the limit of WHO and Pak-EPA. If there is no proper arrangement take place for the removal of As and PTMs from the industrial wastewater and drinking water than within few years all the population around the study area effected with different type of cancer.  相似文献   

2.
Lead levels in different environmental media (soil, grass leaves, water, ceramics, pencil, paint, crayons and cosmetics) were determined to assess the major sources of lead exposure in Thohoyandou, South Africa. Soil and plant leaves were used as indicators of Pb pollution from vehicle exhaust emissions. After digestion with concentrated acids (HNO3, HCl and HClO4) Pb concentrations were determined in triplicate using a flame atomic absorption spectrometer. The mean Pb concentrations at the kerb of selected busy roads were 205.5 ± 90, 273.0 ± 90 and 312.8 ± 81 μg g−1 and 154.7 ± 67, 182.9 ± 76 and 240.6 ± 66 μg g−1 for soil and plant leaves (dry weight) respectively. These concentrations were substantially higher than the values found on soils 50 m away from the roads (97.4 ± 11 μg g−1). Pb concentrations in plants collected further away from the road (50 m) were substantially lower (71.8 ± 9.0 μg g−1). The observed levels on soil are lower than the UK critical value of 500 μg g−1 for gardens and allotments; and 2000 μg g−1 for parks and open space as well as the Canadian values for agricultural (375 μg g−1), residential (500 μg g−1 and industrial (1000 μg g−1). From these data it was clear that Pb concentrations in soil samples were substantially higher than the levels obtained for plant leaves. The Pb levels in green crayons, blue crayons, pencils (from China & Germany), were 10650 ± 75.2, 8200 ± 52.4, 1160 ± 50.2, 79 ± 10.1 μg g−1 for the inner contents; and 4870 ± 58.1, 5650 ± 55.5, 1950 ± 46.6, 60 ± 12.9 μg g−1 for the outer surface paint respectively. The ceramics showed Pb levels of 630 ± 50.3 μg g−1 (saucer) and 560 ± 32.2 μg g−1 (cup), while the inner contents and outer surface paint showed 480 ± 32.4 and 318 ± 21.2 μg g−1 of Pb respectively. Early morning tap water flush gave a Pb level of 20.6 ± 5.6 μg Pb l−1. This value is higher than the WHO and FDA maximum permissible concentrations of 10 μg l−1 and 15 μg l−1 respectively.  相似文献   

3.
While the presence of lead in urban soils from residential lead paint and leaded gasoline is well documented, the relative contribution of lead from area historical industrial activities is not. This study examined the connection between historical industrial sources of lead in Portland, Maine, USA from 1860 to 1970 to current, spatial distributions of soil lead. Collecting 1859 surface and 122 sub-surface soil samples in accordance with USEPA's Lead Safe Yard Protocols, lead concentrations varied from 9 mg/kg to >100,000 mg/kg with most of the samples greater than USEPA's critical value for lead (400 mg/kg). Using historical documents, probable sources of lead were mapped. In comparing two datasets, no clear relationship emerged. Findings were hampered by inability to sample under large areas of impervious surfaces and private properties. Because of lead's immobility in soil, one would expect decreasing concentration with depth, but lead concentrations varied with depth and location. The haphazard dumping of lead-contaminated industrial waste and the relocation of contaminated fill are likely factors. These findings suggest that in urban areas where multiple historical sources of lead existed, surface sampling to determine presence of lead may not be sufficient to protect public health.  相似文献   

4.
Following an examination of blood samples from 1000 persons from Kuwait, a number of important differences in the levels of lead in the blood were noted. There were significant differences between the sexes living in the same residential area. Certain significant lead in blood differences were also found between females and males who dyed their hair, and between smokers and non-smokers. Lead in blood concentrations were also tested for the various blood groups of the respondents. It was noted that O+ blood group respondents were found to have higher lead levels than those of other major blood groups.  相似文献   

5.
The amount of used lead acid batteries rises along with the rapid development of battery manufacture in China. The battery manufacture and recycling industry has developed sharply in these recent 5 years. The annual production of secondary lead from used lead acid batteries in China increased rapidly to 1.5 million tonnes (MT) in 2013, making china the world's largest secondary lead producer. Secondary lead enterprises are mainly located in the middle and eastern regions of China, with a legal production capacity of 3 MT/year. Environmental pollution problems began to happen frequently from 2009. After 2011, the government began to put in efforts to promote pollution control, eliminate outdated production capacity, support advanced production and technology innovation research, and has achieved remarkable results. However, the main existing problems are that the proportion of secondary lead production is only 30% of the total lead production, no formal recycling network has been established and the overall level of industrial technology and equipment is outdated. Compared with developed countries, this paper predicts that, secondary proportion will reach 44% in 2015 and 60% in 2028. Finally some countermeasures are given to the recycling mode and technology promotion.  相似文献   

6.
Urban gardens are often heralded as places for building social, physical, and environmental health. Yet they are also sites of significant conflict based on competing political, economic, and ecological projects. These projects range from radical re-envisionings of liberatory urban spaces, reformist aesthetic and sanitary improvement programmes, to underwriting the production of the neo-liberal city. These projects are based on divergent visions of the garden ground itself, in particular, whether this is soil (the fertile and living source for growing food and social values) or dirt (an inert and even problematic substrate to be removed or built upon for development purposes). These are not fixed or mutually exclusive categories, but are unstable as soil/dirt moves in discursive and material ways over time and space. Contaminants such as lead in the soil contribute to this instability, reframing fertile soil as dangerous dirt. To understand this discursive and material movement of soil/dirt over time and space, a dynamic spatial politics framework is needed that encompasses three scalar concepts: location, duration, and interconnection. This paper applies this dynamic spatial politics framework to interpret the 30-year conflict over the fate of an urban garden in Sacramento, California, that began as a countercultural space and was eventually transformed into a manicured amenity for a gentrifying neighbourhood, and the role of soil lead contamination in this narrative.  相似文献   

7.
成都市幼儿体铅水平与环境铅污染的关系   总被引:4,自引:0,他引:4  
本文检测了成都市 50 1名 3~ 6岁儿童的发铅和血铅水平。发铅平均含量为 17 2 9± 9 70 μg/ g ,血铅平均浓度为 0 59± 0 33μmol/L( 12 3 81± 68 95μg/L)。 60 3%的儿童血铅浓度≥ 0 4 8μmol/L ( 10 0 μg/L) ;3 0 %的儿童血铅浓度≥ 1 4 4 μmol/L( 30 0 μg/L)。发铅与血铅无直线相关关系。市区儿童的发铅和血铅水平显著高于郊区儿童。大气铅测定显示市区铅污染重于郊区。讨论了铅污染的主要来源和儿童铅中毒的预防对策研究。  相似文献   

8.
Empirical scientific evidence indicates that there is still room for increasing food production by improving land productivity. This study aimed at identifying the key determinants that govern farmers’ decisions to adopt multiple components of integrated soil fertility management (ISFM) in a maize mixed cropping system of the Chinyanja Triangle, Southern Africa. Revealed preferences of ISFM components were collected from 320 randomly selected households and multivariate probit (MVP) model was used to analyse the simultaneous effects on adoption based on biophysical plot and household‐level socioeconomic attributes. The results show that farmers’ choices of a set of ISFM components are determined by a mix of factors that address the trade‐offs and synergies among them. Non‐farm income, moderate land quality perception, and education influence simultaneous technology adoption, while gender and crop loss increase the likelihood of farmers’ decisions to adopt independent options. Having other sources of income supports co‐adoption of inorganic fertilizer, residue incorporation, and crop rotation. Input/output market access, access to information, financial sources, and climate variability also play pivotal role in technology adoption. These results indicate that resource availability, learning costs, finances, and risk aversion need to be considered when designing and promoting ISFM technologies as a package.  相似文献   

9.
This study reports on Kenyan school children's ideas about wildlife parks in their country. A comparison is made between the responses of school children in primary school, before they receive any science education, and those of secondary school pupils at the end of the secondary cycle. The findings show little difference between the two groups of students in terms of their ideas about wildlife parks. This has serious implications for science and environmental education in Kenya. Parks are understood by these pupils in terms of real life issues, as derived from social consequences. The children's ideas are all based on the role that parks play in society, but the function of parks to support biodiversity conservation does not seem to be important to the students. While it is satisfying to note that the school children have a good understanding of parks in their social context, it is essential to address fully the scientific and ecological role of parks in order that biodiversity becomes more valued in our society.  相似文献   

10.
原子荧光光谱法测定蔬菜样品中铅   总被引:1,自引:0,他引:1  
铅作为一种对人体有害元素,在蔬菜样品中必须被检测。应用原子荧光光度计检测铅的含量,具有取样量少、灵敏度高、检出限低等优点,适合于环境样品的分析检测。  相似文献   

11.
The study presented in this article used a combination of key informant interviews and a review and synthesis of existing country level literature to identify the major sources of land tenure insecurity in six Southern African countries: Botswana, Lesotho, Malawi, Mozambique, South Africa, and Zambia. Findings reveal that the main causes of land tenure insecurity experienced in Southern Africa include lack of land rights of minority groups, unclear or overlapping land rights, overcrowding, land alienation into leasehold, insecurity of farm workers and farm labour tenants, inappropriate and exploitative administrative practices, land encroachment and illegal settlers and limited women's land rights. The article presents a summary of land tenure security related initiatives that the study countries have or are in the process of adopting. Analysis of these initiatives shows that tenure reforms have focused on changing the law and rules but little has been done to translate new laws into implementable programs; capacity building; prioritization of resources to support tenure reform; provision of complementary policies and incentives; addressing HIV/AIDS‐land tenure related problems; and monitoring and evaluation. The paper contends that these policy issues should be addressed in order to ensure realization of land tenure security for all.  相似文献   

12.
Lead shot deposited in fields and woodlands near shooting rangesand intense, upland, hunting adds an enormous tonnage of lead toenvironments, worldwide. This contamination is not remedied bybanning lead shot use only for waterfowl hunting. Lead pelletsdisintegrate extremely slowly, during which time they may beingested from the soil by wild birds, livestock, or silage-makingmachinery, and cause sublethal or fatal lead poisoning. Leadpellet corrosion products contaminate soil, surface waters, andground waters, often exceeding permissible levels. Plants do notconcentrate much lead from the soil, except when grown in acidicsoils of heavily-contaminated shooting ranges. Inheavily-contaminated sites, earthworms ingest leadcompounds which are bioaccumulated in higher consumersof food webs. Non-toxic substitutes made from steelor bismuth are available internationally and areeffective for all types of hunting and targetshooting. Many nations are slow to require their use,despite the marked awareness of the problems of leadshot contamination and toxicosis. This is due tohunters and international sport shooting organizationsopposing the use of non-toxic substitutes and overtemphasis by government agencies on the burden ofscientific proof for every situation, rather thantaking preventative action according to thePrecautionary Principle. The ethical approach ofDenmark and The Netherlands, which banned all uses oflead shot, is advocated as a precedent for othernations to adopt.  相似文献   

13.
Andersson, Jafet C.M., Alexander J.B. Zehnder, Bernhard Wehrli, and Hong Yang, 2012. Improved SWAT Model Performance with Time-Dynamic Voronoi Tessellation of Climatic Input Data in Southern Africa. Journal of the American Water Resources Association (JAWRA) 48(3): 480-493. DOI: 10.1111/j.1752-1688.2011.00627.x Abstract: In this study, we compared two approaches to obtain climatic time series for the Soil and Water Assessment Tool (SWAT), namely the conventional centroid method and time-dynamic Voronoi tessellation, and assessed the performance of SWAT in simulating discharge and smallholder maize yields in Southern Africa. Climatic time series were estimated with each method. The Voronoi method utilized all available precipitation and temperature data, but the centroid method used only 14.5 and 82.5%, respectively. After centroid processing, sub-basin time series were on average 42 and 63% incomplete, respectively. After Voronoi processing, all time series were complete. SWAT was fed with each climate dataset. Each model setup was independently calibrated and validated against discharge and maize yield. Similar model performance was obtained with both methods for yield. The root mean squared error during calibration was 0.26 and 0.27 t ha−1 for the centroid and Voronoi methods, respectively (p-value: 0.80). However, daily discharge simulations improved significantly with the Voronoi method. The coefficient of determination increased from 0.24 to 0.39 in the calibration period (p-value: 9.6 × 10−13) and from 0.41 to 0.48 in the validation period (p-value: 3.1 × 10−3). The Voronoi method improved the simulation of the river flow regime. The largest improvements were obtained in data scarce situations, at high spatial and temporal resolution, and where the centroid method performed the worst.  相似文献   

14.
采用微波消解-原子荧光光谱法测定了垃圾焚烧飞灰中铅的含量。重点研究了铁氰化钾的用量以及加入盐酸羟胺对测定结果的影响。试验结果表明:加入铁氰化钾可以促进铅烷生成,盐酸羟胺可起到抑制干扰的作用。方法的检出限为0.39μg/L,回收率为83.6%~101.3%。  相似文献   

15.
This study developed a system to plan, evaluate, implement, and monitor a waste reduction and source-separation program, which was then tested through a field study in a New York City elementary school. Despite efforts to implement integrated waste management in elementary schools, appropriate planning tools that document performance and support program development are lacking. To fill this gap, a system for analyzing existing programs was developed. After identifying the phases required for a successful program, a scoring system was developed to quantify the performance of existing programs. To assess existing protocol, recommendations from leading municipalities were reviewed, and the performance of existing programs was quantified within the scoring system. The existing protocol was found to contain similarities, but an overarching approach was needed to connect the provisions with programs that have been successfully deployed. From this analysis, a scoring system was developed to take into consideration the major elements needed for a waste reduction and source-separation plan, colloquially referred to as a recycling plan, as well as the specifics of implementation. This system allows for the review of programs already developed, and can pinpoint limitations prior to implementation. The framework was evaluated through the test case school, with both waste audit data and diagrams. From the lessons learned, successful techniques and recommendations for utilizing this framework were created.  相似文献   

16.
Lead concentrations were determined for particulates which were deposited during one year on the leaves of roadside plants in Karachi. The particulates were collected from the leaves at a height of one metre. The lead accumulated by the leaves of different species was also measured. A statistically significant correlation was found between the number of passing petrol driven vehicles and the lead concentration in the deposits at different designated sites. However, no significant correlation was found between the concentration in the deposits and the lead accumulated by the leaves. A lead concentration of 30.00±6.6 ppm was recorded as the highest concentration in the particulate deposits, while maximum lead accumulated by the leaves was noted as 3.12±1.09 ppm.  相似文献   

17.
阳极溶出伏安法连续测定底泥中的总镉和总铅   总被引:1,自引:0,他引:1  
样品经盐酸-硝酸-氢氟酸-高氯酸消解后,用1+1盐酸溶解残渣,以高氯酸做支持电解质,采用阳极溶出伏安法的标准加入法,测定样品中的总镉和总铅,取得满意结果。  相似文献   

18.
ABSTRACT

Public schools are more than educational institutions; they are essential to creating liveable neighbourhoods. Despite their importance, public schools are being permanently closed across North America, and particularly in the Canadian province of Ontario. In 2015, one of Ontario's public school boards made the decision to permanently close the province's oldest public high school, located in the urban core of the historic midsized city of Kingston. While the school is not scheduled to close until late 2019, the established fate of this prominent public asset has important consequences for the liveability of Kingston's urban core. Accordingly, the objective of this study was to document residents’ perceived impacts of the decision to close to Kingston Collegiate Vocational Institute (KCVI) on liveability in the school's catchment area. We observed widespread dissatisfaction with the decision to close KCVI (85%), with large proportions of respondents (above 40%) anticipating KCVI's closure to negatively impact neighbourhood liveability in various ways in the future. Approximately one-quarter of respondents indicated that they have considered moving as a result of the decision, and among these, concerns about negative impacts to household-level well-being were particularly acute. Given the socio-demographic profile of respondents who have considered moving, these findings suggest that the closure of KCVI could have a destabilising effect on the neighbourhoods within the KCVI catchment area by driving families out of the city's urban core. Our findings suggest that policies to address concerns of under-enrolment are short-sighted and undermine efforts of other sectors to promote liveable communities.  相似文献   

19.
示差脉冲阳极溶出伏安法测定中药川附子痕量铅镉   总被引:6,自引:2,他引:4  
本文报道了以HNO3-HClO4湿法消化、醋酸盐介质法差脉冲阳极溶出伏安法测定中药川附子中的铅镉。样品中铅镉含量分别在0.2-0.4μg.g^-1、0.03-0.16μg.g^-1,回收率90-110%。  相似文献   

20.
We assessed environmental and perceptual correlates of walking and walkability for fifth graders from three communities attending two schools: A new urban/LEED-ND pilot community, mixed, and standard suburban community. Irvine-Minnesota Inventory (IMI) walkability audits showed that new urban blocks provided more traffic safety, pleasurability, crime safety, density, and diversity. New urban routes offered greater traffic safety, accessibility, pleasurability, crime safety, and diversity, but suburban routes had greater housing density, net of controls (parental education, rooms in the home, home ownership, parent preference for child to walk to school). Parents and children perceived new urban routes to be more walkable and children walked more when they lived on more walkable routes. The suburban hierarchical street design exposed children to varied traffic safety conditions by funneling their walks from cul-de-sacs to arterials. The new urban routes to a centrally located school passed by pleasant open spaces, suggesting how community organization can create better walking conditions.  相似文献   

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