高效液相色谱法测定柑橘及橘园土壤中乙撑硫脲残留

建立了高效液相色谱测定柑橘及橘园土壤中乙撑硫脲残留的方法,优化了试验条件.方法在0 mg/L～5.35 mg/L范围内线性良好,橘园土壤、橘皮、橘肉样品的检出限(以鲜重计)分别为0.006 mg/kg、0.008 mg/kg、0.006 mg/kg,样品测定的RSD≤5.1%,加标回收率为82.9%～92.8%.     

气相色谱法测定黄瓜和土壤中代森锰锌的残留及其消解动态分析

采用GC-FPD(S)法测代森锰锌在黄瓜和土壤中的残留,通过优化前处理和检测条件,使方法在0.007 6 mg/L~3.80 mg/L范围内线性良好,在黄瓜和土壤中的方法检出限分别为5.12μg/kg和2.35μg/kg。黄瓜和土壤3个质量比水平的空白加标回收率分别为91.1%~96.5%和82.4%~90.5%,7次测定结果的RSD为5.0%~6.5%和2.4%~4.1%。将该方法用于研究代森锰锌在黄瓜和土壤中的消解动态,得知代森锰锌在黄瓜中的半衰期为3.63 d~4.77 d,在土壤中的半衰期为4.19 d~7.33 d。     

气相色谱法测定柑橘和土壤中螺螨酯残留

以丙酮为提取剂,二氯甲烷为萃取剂,采用弗罗里硅土柱净化,气相色谱-电子捕获检测器测定柑橘和土壤中的螺螨酯残留,优化了样品前处理条件。方法在0.141μg/L～5.65 mg/L范围内线性良好,最低检出限为0.003 5 mg/kg,空白样品在0.050 mg/kg、0.500 mg/kg、1.00 mg/kg 3个添加水平上的平均回收率为82.2%～110%,平行测定的RSD为2.6%～9.8%。     

三峡库区柑橘对土壤重金属吸收富集特征研究

研究区域柑橘果实重金属含量符合NY/T 426-2000<绿色食品柑橘>标准,果实品质达到一级产品.土壤中重金属的含量越高,柑橘叶片、果皮、果肉的重金属含量也越高.柑橘叶片对土壤重金属铜、锌、铅、镉、镍、汞、砷、铬的吸收富集能力显著大于果皮与果肉,果皮对土壤重金属铜、锌、铅、镉、汞的吸收富集能力显著大于果肉,果肉对土壤重金属铬的吸收富集能力显著大于果皮.柑橘同一部位对土壤中不同重金属元素的吸收富集能力也存在很大的差异,柑橘叶片对土壤中不同重金属元素的富集系数大小顺序为Hg＞Pb＞Cd＞Cu＞Zn＞Cr＞As＞Ni,柑橘果皮对土壤中不同重金属元素的富集系数大小顺序为Cd＞Hg＞Cu＞Zn＞Pb＞Cr＞Ni＞As,柑橘果肉对土壤中不同重金属元素的富集系数大小顺序为Hg＞Cu＞Cr＞Zn＞Cd＞Ni＞Pb＞As.     

气相色谱法测定土壤中37种有机磷农药残留

采用气相色谱法测定土壤中37种有机磷农药,当取样量为10 g时,37种有机磷农药方法检出限为0. 002～0. 015 mg/kg,测定下限为0. 008～0. 060 mg/kg。低含量加标样品中有机磷农药的加标回收率为72. 8%～104%,相对标准偏差为4. 2%～13. 8%;中含量加标样品中有机磷农药的加标回收率为71. 5%～101%,相对标准偏差为4. 3%～13. 5%;高含量加标样品中有机磷农药的加标回收率为74. 6%～109%,相对标准偏差为6. 8%～14. 6%。该方法灵敏度高、分离效果好、重现性好,能够满足土壤中37种有机磷农药残留检测的要求。     

催化动力学光度法测定沉积物中痕量镍

研究了氨水介质中痕量镍阻抑高碘酸钾氧化靛蓝胭脂红的指示反应,建立了动力学光度法测定沉积物中痕量镍的新方法.优化了试验条件,方法在0 mg/L～0.45 mg/L线性关系良好,检出限为0.85 μg/g,相对标准偏差为1.8%～2.4%,加标回收率为97.2%～103%.     

毛细管气相色谱法测定烟草中有机氯农药残留

研究了烟草中六六六及滴滴涕异构体含量的气相色谱分析方法.样品以石油醚 丙酮在索氏提取器中提取,提取液以浓硫酸净化.采用DB-5弹性石英毛细管柱分离样品,GC-ECD检测农药六六六、滴滴涕的残留量.方法的线性范围为2.27×10-13～7.66×10-11g;最小检测量为1.3×10-8～3.0×10-7 μg,加标平均回收率为95.3%～103.3%,RSD为2.8%～4.5%.     

微波消解-石墨炉原子吸收法测定蔬菜中痕量铅和镉

采用微波消解-石墨炉原子吸收法测定蔬菜中痕量铅和镉,优化了微波消解程序和石墨炉工作条件,讨论了基体改进剂和微波消解用酸的选择.该方法测定蔬菜中铅和镉的检出限为0.002 mg/kg和0.001 mg/kg,RSD为0.1%～4.3%,加标回收率为98.0%～104%.     

城市污水中PCBs的分析及其QA/QC研究

报道了一种城市污水中痕量PCBs的分析方法,并进行了QA/QC研究,采用二氯甲烷萃取剂对城市污水进行液-液萃取,联合运用浓硫酸和硅胶层析柱将PCBs与杂质分离,以毛细管GC-ECD和内标法对PCBs定量.空白加标回收试验得出,PCBs的回收率为58%～125%,标准偏差为0.00173～0.00778μg/L,相对标准偏差为1.58%～12.43%.以实际城市污水作为加标基质,得出加入污水中的19种PCBs的分析方法回收率为57.6%～129.2%,方法的检测限为0.010～0.056μg/L,满足了US EPA对PCBs回收率要求.经过3次平行测定,测得实际城市污水中PCBs含有9种PCBs,PCBs总量的平均值为0.0235μg/L,相对标准偏差为9.63%,该分析方法所需的仪器简便、容易操作.     

超声波萃取- GC/MS法测定土壤中多氯联苯

建立了超声波萃取、氟罗里硅土柱净化、气相色谱/质谱联用选择离子扫描模式测定土壤样品中多氯联苯Arochlor系列的方法.方法线性良好,灵敏度高,RSD为9.5%～12.2%,加标回收率为65.0%～105%,标准土壤样品的测定结果也符合要求.     

A New Mathematical Approach in Environmental and Life Sciences: Gene–Environment Networks and Their Dynamics

An important research area in life sciences is devoted to modeling, prediction, and dynamics of gene-expression patterns. As clearly understood in these days, this enterprise cannot become satisfactory without acknowledging the role of the environment. To a representation of past, present, and most likely future states, we also encounter measurement errors and uncertainties. This paper surveys and improves recent advances in understanding the foundations and interdisciplinary implications of the newly introduced gene–environment networks, and it integrates the important theme of carbon dioxide emission reduction into the networks and dynamics. We also introduce some operational and managerial issues of practical working and decision making, expressed in terms of sliding windows, quadrants (modules) of parametric effects, and navigating (controlling) between such effects and directing them. Given data from DNA microarray experiments and environmental records, we extract nonlinear ordinary differential equations that contain parameters that have to be determined. For this, we employ modern (Chebychevian) approximation and (generalized semi-infinite) optimization. After this is provided, time- discretized dynamical systems are studied. A combinatorial algorithm with polyhedra sequences allows to detect the region of parametric stability. Finally, we analyze the topological landscape of gene–environment networks with its structural (in)stability. By embedding as a module and investigating CO₂ emission control and figuring out game theoretical aspects, we conclude. This pioneering work is theoretically elaborated, practically devoted to health care, medicine, education, living conditions, and environmental protection, and it invites the readers to future research.      

Assessing health consequences in an environmental impact assessment: The case of Amsterdam Airport Schiphol

In this article a comprehensive approach for the evaluation of possible health effects in an environmental impact assessment (EIA) is described, illustrated with the example of Amsterdam Airport Schiphol. Unlike many EIAs, we estimated quantitatively the impact of aircraft-related pollution in terms of the number of affected people for aircraft noise annoyance, odour annoyance and hypertension. In addition, an analysis of health registry data on cardiovascular and respiratory diseases and a short survey on annoyance and risk perception were carried out. The scope of a health impact assessment depends on the situation, available knowledge and data, concern in the population about the impact and the number of people concerned. It is important to pay attention to the perception of risks and concerns from all parties involved. Moreover, the results demonstrate that far more people outside the area for which standards apply were affected than inside.     

Contaminant Profiles of Two Species of Shorebirds Foraging Together at Two Neighboring Sites in South San Francisco Bay, California

The San Francisco Bay estuary isused by over one million shorebirds during springmigration and is home to several hundred thousandduring the winter. Most shorebird use occurs in thesouthern reach of the estuary (South Bay). Thereduced water circulation and discharge fromindustrial sources in the South Bay are responsiblefor the highest levels of some trace elements in theestuary. Wintering shorebirds have been found to havestrong site fidelity to areas as small as a fewkilometers in the South Bay, which may increase theirexposure to contaminants near local point sources. Inaddition, different shorebird species foraging at thesame site have been shown to have differentcontaminant burdens. Thus, our objectives were totest whether contaminant burdens differed by species,or whether contaminant burdens differed in shorebirdscollected at adjacent sites. We examined thecontaminant profiles of two species of shorebirds,long-billed dowitchers (Limnodromus scolopaceus)and western sandpipers (Calidris mauri) thatforage together at two sites, Hayward and Newark,separated by 8 km in the South Bay. We usedmultivariate analysis of variance tests to compare thecomposition of 14 elemental analytes in their livertissues and estimated their molar ratios of Hg and Se. Composite samples were used for contaminant analysesbecause of the small body size of the shorebirds. Seven elemental analytes (Ag, Ba, Be, Cr, Ni, Pb, V)were below detection limits in a majority of thesamples so statistical analyses were precluded. Inthe measurable analytes (As, Cd, Cu, Hg, Mn, Se, Zn),we found no significant intra-site differences ofcontaminant profiles for the two species. We pooledthe samples to examine inter-site differences andfound significant differences in contaminant profilesbetween shorebirds at the neighboring sites (P = 0.03). Shorebirds at Newark had higher (P < 0.05) concentrations of As, Cd, and Se than those at Hayward. Dowitchers at Newark had concentrations of Hg and Se which were highly correlated (P < 0.003) in a mean molar ratio of 1:19, similar tothat reported in other birds. In the larger dowitcherspecies, we also examined exposure to 20organochlorine compounds. Organic analyses showedthat the dowitchers had been exposed to DDE, PCBs,dieldrin and trans-nonachlor, but with no significantdifferences in concentrations between Hayward andNewark (P > 0.05).     

土壤和底泥中砷、铬、锰测定的前处理技术

试验了土壤和底泥中砷的前处理技术，其目的是能对土壤、底泥中砷、铬、锰在一次前处理中制备成试液，比色法分析。试验表明，用Ｈ２ＳＯ４－Ｈ３ＰＯ４－Ｈ２Ｏ２进行前处理是可行的。方法简单、挥发酸雾少，用标准参考物质检验证明，分解完全，数据准确，有粒较好一致性。     

Geochemical assessment of metal transport in glacial till during electrokinetic remediation

This paper presents the chemical speciation and retention behavior of chromium (Cr), nickel (Ni), and cadmium (Cd) prior to and after the electrokinetic remediation in glacial till soil. The speciation of the metals was predicted using the chemical speciation program MINEQL⁺. The simulations were performed for single-contaminant with only Cr(VI) or Ni, and multi-contaminants consisting of: (1) Cr(VI), Ni, and Cd; (2) Cr(III), Ni and Cd; (3) Cr(VI), Cr(III), Ni and Cd; (4) Cr(VI), Ni, and Cd with reducing agents; and (5) Cr(III), Ni, and Cd with oxidizing agent (Mn). The results showed that the speciation and distribution of cationic metals [Ni, Cd, and Cr(III)] in glacial till soil remain unaffected or slightly affected during electrokinetics. This is attributed to the high pH buffering capacity of the glacial till, leading the metals to precipitate in the soil prior to and after electrokinetics. This study showed that during electrokinetics, Cr(VI) existed as anionic complex and migrated towards the anode and the migration is maximum in case of a single-contaminant system. The study also showed that near the anode in the absence of any reducing and oxidizing agent, Cr(VI) mostly adsorbed, and some of Cr(VI) reduced to Cr(III) and migrated towards the cathode and finally precipitated due to high pH conditions. Ni and Cd remain adsorbed or precipitated due to the high pH conditions throughout the soil. Among the reducing agents, the sulfide had significant effect on the migration of metals compared to ferrous ions. While in the presence of oxidizing agent (Mn), no noticeable Cr(VI) was found in the soil sample indicating the reduction of Cr(VI) to Cr(III) and the predominance of reducing conditions due to the presence of naturally occurring iron in the glacial till soil. Overall, this study provides a reasonable explanation of the speciation and distribution of chromium, nickel and cadmium during the electrokinetic remediation of glacial till soil.     

Biomonitoring of Lead, Zinc, and Cadmium in Streams Draining Lead-Mining and Non-Mining Areas, Southeast Missouri, USA

We evaluated exposure of aquatic biota to lead (Pb), zinc (Zn), and cadmium (Cd) in streams draining a Pb-mining district in southeast Missouri. Samples of plant biomass (detritus, periphyton, and filamentous algae), invertebrates (snails, crayfish, and riffle benthos), and two taxa of fish were collected from seven sites closest to mining areas (mining sites), four sites further downstream from mining (downstream sites), and eight reference sites in fall 2001. Samples of plant biomass from mining sites had highest metal concentrations, with means 10- to 60-times greater than those for reference sites. Mean metal concentrations in over 90% of samples of plant biomass from mining sites were significantly greater than those from reference sites. Mean concentrations of Pb, Zn, and Cd in most invertebrate samples from mining sites, and mean Pb concentrations in most fish samples from mining sites, were also significantly greater than those from reference sites. Concentrations of all three metals were lower in samples from downstream sites, but several samples of plant biomass from downstream sites had metal concentrations significantly greater than those from reference sites. Analysis of supplemental samples collected in the fall of 2002, a year of above-average stream discharge, had lower Pb concentrations and higher Cd concentrations than samples collected in 2001, near the end of a multi-year drought. Concentrations of Pb measured in fish and invertebrates collected from mining sites during 2001 and 2002 were similar to those measured at nearby sites in the 1970s, during the early years of mining in the Viburnum Trend. Results of this study demonstrate that long-term Pb mining activity in southeast Missouri has resulted in significantly elevated concentrations of Pb, Cd, and Zn in biota of receiving streams, compared to biota of similar streams without direct influence of mining. Our results also demonstrate that metal exposure in the study area differed significantly among sample types, habitats, and years, and that these factors should be carefully considered in the design of biomonitoring studies.     

Comparative studies on accumulation of Cr from metal solution and tannery effluent under repeated metal exposure by aquatic plants: its toxic effects

The present study demonstrates comparison of Cr accumulatingpotential by the plants of Najas indica Cham. (submerged),Vallisneria spiralis L. (rooted submerged) and Alternanthera sessilis R. Br. (rooted emergent) under repeatedmetal exposure and its effect on chlorophyll and protein concentrations. These plants were treated with different concentrations of Cr under repeated exposure in controlled laboratory conditions to assess the maximum metal accumulationpotential. The plants of V. spiralis accumulated significantly high amount of Cr under laboratory conditions incomparison to N. indica and A. sessilis. The maximumaccumulation of 1378, 458 and 201 g g^-1 dw Cr was found in the leaves of V. spiralis, N. indica and A. sessilis, respectively at 8 mg L^-1 after 9 day of Cr exposure. These plants have shown a decrease in chlorophyll andprotein concentrations with increase in Cr concentrations. In view of high accumulation of Cr in V. spiralis, the plantswere treated with different concentrations of tannery effluent collected from Common Effluent Treatment Plant, Unnao (UP). Theplants of V. spiralis treated with 100% tannery wastewatershowed the maximum accumulation (57.5 g g^-1 dw) of Cr in the roots after 10 days of exposure. The plants were foundeffective in removing Cr from solution and tannery effluent.     

一起河流砷污染事故的处置与监测分析

介绍了大沙河砷污染事故的处置和监测分析。多介质排查监测摸清了污染的范围和程度,为治理工作提供了科学依据,污染治理措施有效控制了污染的扩散;监测数据表明,治理措施将水中砷污染物沉降至河床使污染水质达标排放。吸附了大量砷化合物的底泥被清理并进一步处置,多介质跟踪监测应持续进行直至不存在潜在危害。     

核应急辐射环境监测的准备和响应

日本核泄漏事故引发的核危机为人类安全和平地利用核能又一次敲响了警钟.核事故应急工作作为减小核电站危害环境和公众安全的最后屏障,将起到重要的作用,必须做好相关的准备和响应工作.核应急辐射环境监测工作是核应急工作的重要组成部分,在对核应急辐射环境监测进行准备和响应时主要遵循实用性、适用性和适度性并兼顾常规和应急监测的“平战...