微波消解-氢化物发生原子荧光法测定植物中汞和砷

采用微波消解-氢化物发生原子荧光法测定植物中汞和砷,优化了试验条件。汞在0μg／L-1．00μg／L、砷在0μg／L～20．0μg/L范围内线性良好,方法检出限汞为0．005mg／kg（以取0．1g样品消解定容至10mL计）,砷为0．010mg／kg（以取0．1g样品消解定容至25mL计）,植物样品测定的RSD≤4．5％,加标回收率为90．0％～107％。     

微波消解石墨炉原子吸收法测定土壤和沉积物中的铍

以氯化钯为基体改进剂,采用微波消解石墨炉原子吸收法测定土壤和沉积物中的铍,优化了微波消解条件,考察了共存元素对测定的干扰。方法在0μg／L～4．00μg／L范围内线性良好,检出限为0．01μg／g（以取样质量0．2000g、定容体积50mL计）,标准样品平行测定的RSD为3．5％～6．7％,实际样品的加标回收率为84．0％-113％。     

微波消解-石墨炉原子吸收法测定土壤中钒

建立了微波消解-石墨炉原子吸收测定土壤中钒的方法,优化了微波消解程序。方法在0μg／L～100μg／L范围内线性良好,以称样0．5000g、定容体积50mL计,方法检出限为0．2μg／g,环境土壤标准样品测定的RSD为2．5％,加标回收率为92．0％-104％。     

微波消解-ICP/MS法同时测定水产品中13种元素

用硝酸-双氧水体系微波消解,以In、Sc为内标,采用电感耦合等离子体质谱法（ICP／MS）同时测定水产品中V、Cr、C0、Ni、Cu、Zn、As、Se、Cd、Sb、Ba、T1、Pb等13种元素。各元素的检出限在0．05ng／g～0．064μg／g之间,样品平行测定4次的RSD〈5％,鲢鱼样品的加标回收率在81％～117％之间。     

原子荧光光谱法测定水中低含量锡

采用原子荧光光谱法测定水中锡,结果表明,方法检测限为0．14μg／L,在0、0μg／L～100μg／L范围内线性良好。不同浓度标准溶液测定的相对误差≤2．0％,实际样品测定的加标回收率在90．0％～109％之间,相对标准差≤6．1％,准确度和精密度均较好。     

固相萃取-毛细管气相色谱法测定地表水中硝基苯类化合物

建立了固相萃取-毛细管气相色谱测定地表水中硝基苯类化合物的方法,优化了试验条件。方法线性良好,10种硝基苯类化合物的检出限为0．05μg／L～0．15μg／L,实际样品测定的RSD为1．7％～5．0％,平均加标回收率为80．8％～117％。     

超声波提取-GC/MS法测定生物体内硝基苯类化合物

以洪泽湖中6种代表性生物为研究对象,采用超声波法提取样品中硝基苯类化合物,用凝胶色谱净化、浓缩,气相色谱／质谱联用法测定。该法与索氏提取法在同等试验条件下进行加标回收试验,前者回收率高且稳定,简便可行。方法检出限为0．008μg／g～0．030μg／g,平均加标回收率为76．5％～109％,重复测定3次的RSD为1．5％～13．0％。     

支撑离子液体膜微萃取-气相色谱法测定水中有机氯农药

摘要：将l-丁基-3-甲基咪唑六氟磷酸离子液体固定于无纺布上形成支撑离子液体膜,结合液相微翠取技术对水样中的有机氯农药进行分离与富集,并用气相色谱法测定。通过试验对影响萃取效率的有关条件进行优化,使该方法在0．500μg／L～10．0μg／L范围内线性良好。方法检出限为0．02μg／L～0．08μg／L,测定0．04μg／L的混合标准溶液平均回收率为75．0％～87．3％,RSD〈7％。     

吹扫捕集-气质联用法测定水中9种酯类物质

采用吹扫捕集-气相色谱／质谱联用法测定水中9种酯类有机物,加入硫酸钠盐提高灵敏度,当硫酸钠过饱和时,吹扫捕集效率最高。9种酯类有机物在一定的质量浓度范围内线性关系良好,方法检出限为0．14μg／L～0．25μg／L,模拟样品平行测定的RSD为0．6％～1．8％,加标回收率为80％～106％。     

固相膜萃取-高效液相色谱法测定地下水中的多环芳烃

采用C18固相膜萃取对地下水中15种多环芳烃进行富集净化,以二氯甲烷作洗脱溶剂,高效液相色谱法,荧光检测器测定。对萃取、浓缩和色谱条件进行优化,在1．ooixg／L～40．0μg／L范围内测定标准系列溶液并绘制标准曲线,相关系数R2〉0．999;15种多环芳烃的仪器检出限为0．4ng／L～3．0ng／L;对地下水样品加标,平均回收率在75．7％～96．7％之间;标准溶液平行测定7次的RSD为3．1％～11．9％。     

Topsoil and Housedust Metal Concentrations in the Vicinity of a Lead Battery Manufacturing Plant

The aim of the study was to determine the extent of heavy metal pollution in the vicinity of a lead battery manufacturing plant in the Czech Republic, both in the general environment and within homes. Topsoils (0–5 cm) were sampled from 100 sites along 4 transects which crossed the battery factory, the town centre and outlying rural areas. Housedust samples were collected from 15 plant-workers' homes and 15 non plant-workers' homes located at various distances from the factory. Samples were analysed for levels of Pb, Zn, Cd, Cu, As and Sb, using ICP-AES. Soil concentrations of Pb, Cd, As and Sb peaked at the perimeter fence of the battery factory with Pb levels of up to 12 650 g g> ^-1. Concentrations of these metals decreased exponentially within 500 m of the plant. Whilst the battery factory does appear to be a source of all the metals with the exception of Zn, emissions do not appear to be transported to any great extent over distances of more than 0.5 km. Topsoil and housedust concentrations of Pb, Zn, Cd, Cu, As and Sb in the general Mlada Boleslav area do not appear to be significantly different from those recorded in a large scale survey of urban soils in the United Kingdom. A comparison of housedust Pb concentrations in homes of plant workers and non-plant workers suggests that there may be a small input of Pb into the home environment by battery plant employees.     

微波消解-原子吸收光度法测定土壤中铜锌铅镉镍铬

用微波消解－原子吸收光度法测定土壤中铜，锌，铅，镉，镍和铬。通过硝酸－氢氟酸－过氧化氢体系消解液对土壤样品消解，选择出微波最佳消解条件。对硝酸－盐酸－过氧化氢体系消解液和硝酸－氢氟酸－过氧化氢体系消解液进行消解对比试验，发现前者不能将土壤样品完全消解，后者能将样品消解完全，但需将消解液中剩余的酸赶尽，否则测定结果将明显偏低。微波消解土壤与传统电热消解相比，操作简便快速，可提高工作效率。     

An Overview of Contaminant-Related Issues Identified by Monitoring in San Francisco Bay

The San Francisco Estuary Regional Monitoring Program for Trace Substances (RMP) began in 1993 and is sponsored by 74 local, state, and federal agencies and companies through their discharge or Bay use permits. The RMP monitors water, sediment, toxicity, and bivalve bioaccumulation at 25 sites in the Bay that are considered to represent "background" conditions. Several major environmental issues have been identified by the RMP. Polychlorinated biphenyls and mercury were often above water quality guidelines, and often occurred in fish tissues above U.S. Environmental Protection Agency (U.S. EPA) screening values. Concentrations do not appear to be decreasing, suggesting continuing inputs. Episodes of aquatic toxicity often occurred following runoff events that transport contaminants into the Bay from urbanized and agricultural portions of the watershed. Sediment toxicity occurred throughout the Bay, and has been correlated with concentrations of specific contaminants (chlordanes, polynuclear aromatic hydrocarbons) at some locations; mixtures of contaminants were probably also important. Since the RMP does not monitor all ecosystem components, assessments of the overall condition of the Bay cannot be made. However, in terms of contamination, the RMP samples suggest that the South Bay, and North Bay sites are moderately contaminated.     

Biomagnification factors (fish to Osprey eggs from Willamette River,Oregon, U.S.A.) for PCDDs,PCDFs, PCBs and OC pesticides

A migratory population of 78 pairs of Osprey (Pandion haliaetus) nesting along the Willamette River in westernOregon was studied in 1993. The study was designed to determinecontaminant concentrations in eggs, contaminant concentrationsin fish species predominant in the Ospreys diet, andBiomagnification Factors (BMFs) of contaminants from fish specieseaten to Osprey eggs. Ten Osprey eggs and 25 composite samplesof fish (3 species) were used to evaluate organochlorine (OC)pesticides, polychlorinated biphenyls (PCBs), polychlorinateddibenzo-p-dioxins (PCDDs), and polychlorinated dibenzofurans(PCDFs). Mercury was also analyzed in fish. Geometric meanresidues in Osprey eggs were judged low, e.g., DDE 2.3 g g^-1 wet weight (ww), PCBs 0.69 g g^-1, 2,3,7,8-TCDD 2.3 ng kg^-1, and generally well below known threshold values for adverse effects on productivity, and the population was increasing. Osprey egg residue data presentedby River Mile (RM) are discussed, e.g., higher PCDDs were generally found immediately downstream of paper mills and eggsfrom the Willamette River had significantly elevated PCBs and PCDDs compared to reference eggs collected nearby in the CascadeMountains. Prey remains at nest sites indicated that the Largescale Sucker (Catostomus macrocheilus) and NorthernPikeminnow (Ptychocheilus oregonensis) accounted for an estimated 90.1% of the biomass in the Osprey diet, and composite samples of these two species were collected from different sampling sites throughout the study area for contaminant analyses. With the large percentage of the fishbiomass in the Osprey diet sampled for contaminants (and fisheaten by Ospreys similar in size to those chemically analyzed),and fish contaminant concentrations weighted by biomass intake, a mean BMF was estimated from fish to Osprey eggs for the largeseries of contaminants. BMFs ranged from no biomagnification(0.42) for 2,3,7,8-TCDF to 174 for OCDD. Our findings for themigratory Osprey were compared to BMFs for the resident HerringGull (Larus argentatus), and differences are discussed. Webelieve a BMF approach provides some basic understanding ofrelationships between contaminant burdens in prey species offish-eating birds and contaminants incorporated into their eggs,and may prove useful in understanding sources of contaminants inmigratory species although additional studies are needed.     

The Draft of the New German Guideline VDI 3782/8 to Model Automobile Exhaust Dispersion

The draft of the German guideline to calculate automobile exhaust dispersion is explained. It contains a two-stage-system: For first quick estimates the guideline contains the simple models MLuS and STREET. In case these models are not applicable or their results shows concentration levels close to the air quality standards, the more complex models PROKAS_V and MISKAM are recommended. PROKAS_V is a Gaussian plume model, MISKAM is a 3-dimensional microscale non hydrostatic flow model for built-up areas with an Eulerian dispersion model. The guideline comprises cases in rural areas without or with few adjacent buildings as well as urban areas with buildings near the roads. The contribution gives information about the models, typical results and some of the problems showing up presently.     

Hydrocarbon Utilization in Yeast Isolates Found to Grow in Association with Petroleum in a Polluted Ultisol of Midwestern Nigeria

The population counts of hydrocarbon-utilising yeasts weremonitored at six sampling stations in the Benin City municipalarea over a four-week period. Although the population countswere relatively constant in each locality, the highest countsoccurred in areas heavily polluted by domestic and industrialeffluents. A total of thirty-five hydrocarbon-degrading yeastswere isolated from soil at the sampling stations usingn-hexadecane as sole carbon source. The isolates were identifiedas belonging to the genera Candida (27 strains), Endomycopsis (4 strains). All the organisms grew on long-chainn-alkane, kerosene, diesel oil and crude oil but failed to growon short-chain n-alkane, aromatic and alicyclic hydrocarbons.Measurement of growth attributes of the isolates usingn-hexadecane, diesel oil and crude oil as substrates showed thatthe Candida species were better utilizers of hydrocarbonsubstrates relative to Endomycopsis and Schizosaccharomyces species.     

Hydrologic–Economic Model for Managing Irrigation Intensity in Irrigation Areas under Watertable and Soil Salinity Targets

This paper gives mathematical details and sample applications of SWAGMAN Farm (SWAGMAN, Salt Water and Groundwater Management), a farm-scale hydrologic economic model that integrates agronomic, climatic, irrigation, hydrogeological and economic aspects of irrigated agriculture. The model is capable of determining optimum mix of land use to keep watertable and soil salinity within acceptable limits while maximising the economic returns. Alternatively, the model can simulate water and salt balance and economics of a given cropping preference. Web-based and Geographic Information Systems versions of the model are available for integration with the environmental reporting systems of the irrigation areas.     

火焰原子吸收光谱法测定苏州开发区26种蔬菜中铜锌铁锰镍

用火焰原子吸收光谱法测定了苏州开发区26种蔬菜中的铜、锌、铁、锰和镍的含量。蔬菜样品用硝酸高氯酸混合酸进行消解。4次测定值的相对标准差<5%,加标回收率在92%～107%之间。26种蔬菜中铜、锌、铁、锰、镍的含量基本均在世贸组织规定的范围内。     

Using Multiple Taxonomic Groups to Index the Ecological Condition of Lakes

Biological indicators of communitiestypically reflect a common environmental signalreflecting the general condition of the ecosystem, as well asindividual signals by indicators differentiallysensitive to particular environmental conditions. Wedescribe here a method of integrating and interpretingsuch indicators from 19 New England lakes for fivetaxonomic groups (diatoms, benthos, zooplankton, fish,and birds). Our approach provides a systematicstandardized way to integrate multiple metrics fromdifferent taxonomic groups by addressing four elementscrucial to analyzing data from multiple indicators: covariate control, re-scaling of data, standardizing the sign of responses, and dimensional reduction. We evaluated the biologicalmetrics against individual environmental stressors andagainst multivariate physicochemical metricscharacterizing general anthropogenic stress among thelakes. The method detected a response to variationin the gross environmental condition of the lakes thatwas correlated across taxa and metrics. In addition,a differential response to near shore conditions wasdemonstrated for fish. The success of the approach inthis study lends support to its general application toecological monitoring involving complex data sets.     

Concentrations of Cadmium, Mercury and Selenium in Blood, Liver and Kidney of Common Eider Ducks from the Canadian Arctic

We determined concentrations of selected trace elements inlivers, kidneys and blood samples from common eiders (Somateria mollissima borealis) from the eastern Canadianarctic during 1997 and 1998. Concentrations of totalmercury and organic mercury were generally low in the liversof these birds (less than 6 and 4 g g^–1 dry wt,respectively). Selenium ranged between 11–47 g g^–1 inlivers. Renal cadmium concentrations were among the highestever published for this species (range: 47–281 g g^–1). The regressions of log-transformed concentrations ofthese trace elements in blood samples on those in liver orkidney were significant (all P-values < 0.05) andpositive. However, except for organic mercury (RM ² = 0.83), the co-efficients of determination were low tomoderate (range of R ²: 0.26–0.52), suggesting poorto moderate predictive capability. Furthermore, therelationships between total mercury in blood and liverchanged between 1997 and 1998, suggesting that it would notbe possible to predict consistently, concentrations ofmercury in blood from those in liver based on samples takenin one year. Blood samples can be used to determineconcentrations of these trace elements in common eiders (andprobably other sea duck species as well). The use of bloodsamples is especially warranted when it is undesirable tokill the animal such as when working with rare or endangeredsea duck species or when the objective is to relate traceelement exposure to annual survival rates. However, thepredictive equations developed here should not be used topredict expected concentrations in one type of tissue fromthose in the other.