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81.
Qiu Cai Mei-Li Long Ming Zhu Qing-Zhen Zhou Ling Zhang Jie Liu 《Environmental pollution (Barking, Essex : 1987)》2009,157(11):3078-3082
Cadmium (Cd) and Lead (Pb) are environmental pollutants. Environmental samples and bovine tissues were collected from the areas around a lead–zinc smelter in Guizhou, China for Cd, Pb, zinc (Zn) and copper (Cu) analysis. Cd in soil (10 mg/kg) and feed (6.6 mg/kg) from the polluted areas was 10 times higher than the Chinese Standards, resulting in higher Cd in bovine kidney (38 mg/kg) and liver (2.5 mg/kg). Pb in feed (132 mg/kg) from the polluted area was much higher than unpolluted areas, causing higher Pb levels in bovine tissues. Environmental Zn was elevated, but bovine tissue Zn was normal. Cu in bovine liver decreased with increased Cd and Pb. Metals in drinking water and in bovine muscle were within the Standard range. Thus, in the areas of this lead–zinc smelter, the environment has been contaminated with Cd and Pb, which has been transferred to cattle through the food chain. 相似文献
82.
Endosulfan in China 1—gridded usage inventories 总被引:9,自引:0,他引:9
Jia H Li YF Wang D Cai D Yang M Ma J Hu J 《Environmental science and pollution research international》2009,16(3):295-301
Background, aim, and scope Endosulfan, an organochlorine pesticide (OCP), is genotoxic in mammalian cells and generally considered to be toxic and classified
by the World Health Organization and the US Environmental Protection Agency as priority pollutants and a nominator for inclusion
in a future iteration of the persistent organic pollutants treaty. Endosulfan is a currently used pesticide and still being
used worldwide. The general trend of total global endosulfan use has increased continuously since the first year when this
pesticide was applied. It is critical to create national endosulfan usage/emission inventories for China to carry out source–receptor
relation analysis, risk assessment, and other research related to endosulfan in this country. Chinese inventories have been
published for some OCPs, such as technical HCH and lindane, DDT, and chlordane; for endosulfan, however, there has not been
any usage inventory available on any scales (national or provincial), although endosulfan has been widely used since 1994
in this country. This is the first part of the work. The goal of this paper is to quantify the historical production and usage
of endosulfan in China and to compile gridded historical usage inventories of endosulfan for this country. Based on these
usage inventories, emission and residue inventories will be created, which is the goal of the second part of the work.
Materials and methods Due to the lack of national production and usage information of endosulfan in China, a method to estimate the use of endosulfan
was developed. First, information of crops on which endosulfan is applied and average endosulfan use and annual application
frequencies of endosulfan on these crops were collected. Secondly, usage of endosulfan on each crop was estimated using the
national cropland area for each province from Chinese government reports. Finally, with the help of GIS (geographic information
system), the usage data of this insecticide was allocated to a grid system, with a 1/4° longitude by 1/6° latitude resolution,
with a size for each grid cell of approximately 25 km by 25 km.
Results and discussion The use of endosulfan in agriculture in China started on cotton in 1994, and on wheat, tea, tobacco, apples, and other fruits
in 1998. Endosulfan usage on cotton, wheat, tea, tobacco, and apples in China has been estimated to be approximately 25,700 t
between 1994 and 2004. The province with the highest usage of endosulfan is Henan Province, with a total usage reaching 4,000 t,
followed by the uses in Xinjiang Autonomous Region (3,200 t), Shandong Province (3,000 t), Hebei Province (2,100 t), and Anhui
Province (1,900 t). Gridded usage inventories of endosulfan at a 1/4° longitude by 1/6° latitude resolution have been created,
which indicate that the intensive endosulfan use was in the south of Hebei Province, west of Shandong Province, east of Henan
Province, north of Anhui Province, east of Jiangsu Province, and some areas in Yunnan Province and Xinjiang Autonomous Region.
General agreement has been found between the usage data from our estimation and the small amount of usage data published in
China.
Conclusions This is the first national gridded endosulfan usage inventory produced for China. The annual applications of endosulfan from
1994 to 2004 in China were estimated based on the total areas of major crops, on which endosulfan was applied, and spatial
distribution of the application was generated at provincial and prefecture levels. With the help of GIS, endosulfan usage
based on prefecture was transferred to a 1/4° longitude by 1/6° latitude gridding system. The satisfaction of the inventories
was supported by the consistence between the estimation of the annual usage and the reported annual production of endosulfan.
Recommendations and perspectives This gridded endosulfan usage inventory created in this study will be improved upon availability of new information of endosulfan.
The usage inventories can be used to create gridded emission and residue inventories for this insecticide. It is believed
that this work will pave the way for further endosulfan studies in China and beyond. 相似文献
83.
从某印染厂废水排放出口的污泥中分离到一株活性艳蓝X-BR染料高效降解菌LPY68-14,经生理生化鉴定,该菌为埃希氏菌(Escherichia sp.).研究了影响菌株LPY68-14降解效果的因素,实验结果表明:在缺氧、质量分数为0.2%葡萄糖为外加碳源、温度37℃、接种量4 mL、pH 7的最佳条件下,质量浓度为30 mg/L的活性艳蓝X-BR经菌株LPY68-14处理24 h后的降解率可达80%;当活性艳蓝X-BR质量浓度为100~400 mg/L时,该菌处理48 h后的降解率可稳定在70%左右. 相似文献
84.
我国钛白粉工业发展现状与环境政策研究 总被引:1,自引:1,他引:0
针对我国钛白粉工业发展的现状与存在的问题,深入分析造成钛白粉上业现状的原因,并从环保角度提出对策与建议. 相似文献
85.
可靠性理论在公共安全领域的应用研究 总被引:2,自引:0,他引:2
对公共安全体系从系统可靠性的视角,综合运用可靠性方面的知识,构建公共安全系统混联模型;进而将可靠性分配理论与故障树分析方法相结合,根据系统安全目标的要求,确定混联系统的第一层次各单元事件的可靠性目标值,对构成各单元的各个下属单元采取最小工作量可靠度分配方法,从而建立系统中各单元可靠度再分配量化模型。通过建筑物火灾引起人员伤亡事故实例,详述系统各单元可靠性分配的计算过程。研究表明,可靠性理论可以成功地应用到公共安全领域;使系统在给定的目标值条件下达到系统的安全性优化,实现了公共安全保障效能,减小灾害损失。 相似文献
86.
87.
Effective removal of coordinated copper from wastewater using a new dithiocarbamate-type supramolecular heavy metal precipitant 总被引:1,自引:0,他引:1
A new dithiocarbamate-type heavy metal precipitant, sodium 1,3,5-hexahydrotriazinedithiocarbamate (HTDC), was prepared and used to remove coordinated copper from wastewater. In the reported dithiocarbamate-type precipitants, HTDC possesses the highest percentage of the effective functional groups. It could effectively precipitate copper to less than 0.5 mg l−1 from both synthetic and actual industrial wastewater containing CuEDTA in the range of pH 3–9. UV–vis spectral investigation and elemental analysis suggested that the precipitate was a kind of coordination supramolecular compound, [Cu3(HTDC)2]n. The toxicity characteristic leaching procedure (TCLP) and semi-dynamic leaching test (SDLT) indicated that the supramolecular precipitate was non-hazardous and stable in weak acid and alkaline conditions. Tests of an anion exchange resin D231 provided a clue to simultaneously remove excess HTDC and residual CuEDTA in practical process of wastewater treatment. 相似文献
88.
89.
Metal contents (Al, Ca, Cd, Cr, Cu, Fe, Hg, Mg, Mn, Ni, Pb, Ti, and Zn) have been measured in 30 surface soils on Fildes Peninsula, King George Island, Antarctica, yielding values (in milligrams kilogram(-1)) of 41.57-80.65 (Zn), 2.76-60.52 (Pb), 0.04-0.34 (Cd), 7.18-25.03 (Ni), 43,255-70,534 (Fe), 449-1,401 (Mn), 17.10-64.90 (Cr), 1,440-25,684 (Mg), 10,941-49,354 (Ca), 51.10-176.50 (Cu), 4,388-12,707 (Ti), 28,038-83,849 (Al), and for Hg (in nanograms gram(-1)) 0.01-0.06. Relative cumulative frequency analysis was used to determine the baseline values for the 13 metals. Compared with adjacent areas in Antarctica, Mg and Ni are significantly lower, but Cu is significantly higher than that of McMurdo Station. Enrichment factor analysis and the geo-accumulation index method were applied in order to determine the extent of anthropogenic contamination, and both show that Pb, Cd, and Hg have been significantly increased by human activities. Principal component analysis was used to identify the sources of metals in these soil samples. 相似文献
90.
This paper analyzes the relationship between the cultivated land use functions and the land rental decisions of rural households in three Dominant Functional Zones of Hubei, China. The results indicate that 41.10% of the rural households in the study areas participated in the land rental market. The land rental market in the Key Development Zone has both a higher participation rate and land rent; the Agricultural Production Zone has a higher participation rate but a lower land rent; and the land rental market in the Key Ecological Zone is underdeveloped. The difference in regional function and economic level leads to a significant difference in the spatial variation of the cultivated land use multifunction. Overall, the cultivated land function of rural households has a significant impact on their land transfer behavior. The higher the Functions of Economic Contribution, Food Production, and Pension & Employment, the more willing the rural households are to rent in the land, while the higher the Function of Inheritance and Retainment of the cultivated land use, the more likely the peasants are to retain their cultivated land resources. Furthermore, the correlation coefficient is significantly higher in the Key Development Zone than in the Key Ecological Zone. 相似文献