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151.
152.
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
153.
一株高效脱硫脱氨氮菌的分离、鉴定及系统发育分析 总被引:2,自引:1,他引:1
从运行稳定的能同步脱臭的曝气生物滤池中采集样品,富集分离获得一株能高效脱硫脱氨氮的菌株TS-1。对分离菌株进行形态观察、生理生化试验及16S rRNA基因序列分析,结果表明,该菌株TS-1为革兰氏阳性菌,杆状;菌落在营养琼脂培养基上呈圆形,表面光滑,乳白色半透明;V-P试验阴性,能水解淀粉和明胶,利用柠檬酸盐生长;对菌株进行16S rRNA的PCR扩增,扩增产物测序结果表明分离菌株TS-1与巨大芽孢杆菌(Bacillus megaterium)同源性达到99%;以16S rRNA同源性为基础构建了包括24株相关种属细菌在内的系统发育树,在系统发育树中,分离菌株TS1与Bacillus megaterium在同一分支。结合形态观察、生理生化试验及16S rRNA基因序列分析结果,将其初步鉴定为巨大芽孢杆菌(Bacillus megaterium)。在常温(30±2)℃、转速为150 r/min的条件下,处理pH 7、S2-和NH+4-N分别为80 mg/L和88 mg/L的水样40 h,硫化物和氨氮的脱除率分别为91.8%和96.6%。 相似文献
154.
研究了有机高分子絮凝剂NCTS-M对中性兰染料的絮凝性能。通过测量絮体的Zeta电位以及对絮体进行彩色电视显微扫描初步探讨了该絮凝过程的絮凝机理。结果表明,当投加量为30 mg/L,pH=6时,絮凝效果最明显,脱色率可达93.1%。其絮凝机理主要是压缩双电层以及高分子吸附架桥作用,以压缩双电层为基础。絮凝剂中镁离子在中性条件下对絮凝过程也起到了较强的助凝作用。 相似文献
155.
环境中苯并(a)芘监测技术及建议 总被引:1,自引:0,他引:1
环境中BaP是引起人们各类癌症的主要诱发物.叙述了环境中BaP的来源及其浓度状况,列举了国家制定的各项标准中的BaP含量的浓度限值,论述了环境水中和空气中BaP的样品采集、保存、前处理、分析测定及定量监测中应注意的几个问题,提出了监测BaP的4点建议. 相似文献
156.
简述了塔山水库蓝藻暴发的过程及成因。指出 ,由于水库的营养物质增多、水质恶化 ,在不利的水文、气象 (高温、光照充足、微风 )等条件下 ,导致蓝藻暴发。提出了相应的控制对策 相似文献
157.
Seasonal variation of polycyclic aromatic hydrocarbons in soil and air of Dalian areas, China: an assessment of soil-air exchange 总被引:1,自引:0,他引:1
The seasonal variations of concentrations of PAHs in the soil and the air were measured in urban and rural region of Dalian, China in 2007. In soil, mean concentrations of all PAHs in summer were larger than those in winter, whereas the concentrations of heavier weight PAHs in winter were larger than those in summer. Winter/summer concentration ratios for individual PAHs (R(W/S)) increased with the increase of molecular weight of PAHs in soil, indicating that PAHs with high molecular weight were more easily deposited to soil in winter than summer. In air, mean concentrations of all PAHs in winter were larger than those in summer. In comparison with the R(W/S) in soil, all the values of R(W/S) in air were larger than one indicating that the entire individual PAH concentrations in winter were larger than those in summer. The average concentration composition for each PAH compound in soil and air samples was determined and the seasonal change of PAH profile was very small. It was suggested that PAHs in soils and air had the same or similar sources both in winter and summer. The approach to the soil-air equilibrium was assessed by calculating fugacity quotients between soil and air using the soil and air concentrations. The calculated soil-air fugacity quotients indicated that soil acted as a secondary source to the atmosphere for all lighter weight PAHs (two-three rings) and it will continue to be a sink for heavier weight PAHs (five-six rings) in the Dalian environment, both in winter and summer. Medium weight PAHs (four-five rings) were close to the soil-air equilibrium and the tendency shifted between soil and air when season or function region changed. The fugacity quotients of PAHs in summer (mean temperature 298 K) were larger than those in winter (mean temperature 273 K), indicating a higher tendency in summer than winter for PAHs to move from soil to air. The variation of ambient conditions such as temperature, rainfall, etc. can influence the movement of PAHs between soil and air. Most of the fugacity quotients of PAHs for the urban sites were larger than that for the rural site both in winter and summer. This phenomenon may be related with that the temperatures in urban sites were higher than those in the rural site because of the urban heat island effect. 相似文献
158.
Column studies on transport of deicing additive benzotriazole in a sandy aquifer and a zerovalent iron barrier 总被引:2,自引:0,他引:2
Benzotriazole (BTA), a chemical with wide industrial applications, is a typical additive in deicer/anti-icer used at airport. To achieve a better understanding of the transport behaviour and environmental fate of BTA, laboratory column studies have been performed on subsoil samples from Oslo Airport, Gardermoen. To explore possibilities for aquifer remediation, BTA behaviour was also studied in a column of granular zerovalent iron (Fe(0)). The subsoil column study demonstrates a very limited retardation of BTA. Consecutive loadings of BTA of the subsoil column showed no change of the break-through curve (BTC) and complete desorption was observed. The sorption behaviour of BTA to metallic iron (Fe(0)) was rather complex. Considerable retardation was observed in the Fe(0) column and repeated BTA loading resulted in an earlier break-through. Between 20% and 50% of the input concentration was retained permanently in the iron (Fe(0)) column. The BTA sorption to metallic iron was found to be enhanced by chloride which lowered the break-through concentration (i.e the C/C(0) plateau). The fraction of BTA remaining in the iron column was found to vary with the flow rate, indicating a time dependant multilayer sorption mechanism. The steady increase in the amount of adsorbed BTA to the iron column during loading corresponds to a rather strong bonding of 4-15 BTA layers to the iron surface. A very slow desorption of BTA was observed; even after flushing with 753 pore volumes of BTA free water, 7.5% of the BTA remained in the column. A geochemical model was developed based on PHREEQC-2 to simulate the sorption and transport of BTA in the tested materials. The BTA sorption was modelled with Freundlich sorption isotherms, as earlier determined in batch experiments. A slight adjustment of the Freundlich parameters was required to fit the observed column break-through. However, our model was not able to simulate the long-term retainment of BTA in the granular iron columns. The simulations confirm the high mobility of BTA in groundwater aquifers and suggest that zerovalent iron could be used to retain a BTA plume, although oxidation of the sorbent might reduce the long-term performance of such a remediation scheme and slow desorption has been observed. 相似文献
159.
A biomimetic absorbent for removal of trace level persistent organic pollutants from water 总被引:1,自引:0,他引:1
A novel biomimetic absorbent containing the lipid triolein was developed for removing persistent organic pollutants (POPs) from water. The structural characteristics of the absorbent were obtained by SEM and a photoluminescence method. Under optimum preparation conditions, triolein was perfectly embedded in the cellulose acetate (CA) spheres, the absorbent was stable and no triolein leaked into the water. Dieldrin, endrin, aldrin and heptachlor epoxide were effectively removed by the CA--triolein absorbent in laboratory batch experiments. This suggests that CA-triolein absorbent may serve as a good absorbent for those selected POPs. Triolein in the absorbent significantly increased the absorption capacity, and lower residual concentrations of POPs were achieved when compared to the use of cellulose acetate absorbent. The absorption rate for lipophilic pollutants was very fast and exhibited some relationship with the octanol--water partition coefficient of the analyte. The absorption mechanism is discussed in detail. 相似文献
160.
根据《危险化学品名录》,分析江苏省取得危险化学品安全生产许可证的1774家企业的化学品种类、数量、生产企业类型分布情况.结果表明,江苏省危险化学品生产企业在地域分布上苏南多于苏北;化工、建材行业的危险化学品生产企业所占比例较高;危险化学品涉及除爆炸品外的6大类,达3 790种,以生产易燃液体的企业数目为最多;有31家企业生产10种以上危险化学品.笔者建议,通过评估摸清企业安全生产状况,严格控制危险化学品企业安全生产许可证发放,实现危险化学品运输企业的动态管理,建立安全监测预警技术平台. 相似文献