顶空-便携式气相色谱法测定土壤中的苯系物

建立了顶空-便携式气相色谱快速测定土壤中苯、甲苯、乙苯、间对二甲苯、邻二甲苯的方法,并讨论了无机盐及振荡时间等因素对顶空分析灵敏度的影响。结果表明,方法回收率为87.2%~105.1%,相对标准偏差(RSD)5.3%~7.8%,最低检出限为0.1~0.8μg/kg;苯、甲苯、乙苯、间对二甲苯、邻二甲苯的线性范围分别为0.8~160μg/kg、1.6~320μg/kg、2.0~400μg/kg、2.0~400μg/kg和3.2~800μg/kg。方法回收率、RSD与标准方法相比没有显著性差异,较之标准方法其更能满足现场快速监测的需要。     

莱州湾表层沉积物中多氯联苯的测定方法及分布特征探究

以加速溶剂萃取法 (ASE)、索氏提取法/气相色谱法测定了莱州湾表层沉积物中的12种PCBs的浓度水平,探讨了它的分布特征并将两种方法进行了对比;同时测定了渤海湾北部海域表层沉积物中PCBs的含量,与莱州湾进行了比较。结果表明,莱州湾海域表层沉积物检测出8种多氯联苯(PCBs),浓度范围是N.D.~48.40 ng ·g ^-1dw。该海域多氯联苯的分布特征是近岸高,离岸低,由近岸向湾外延伸方向依次递减;渤海湾PCBs的浓度范围是0.15~68.30 ng ·g ^-1dw,和莱州湾差别不大。索氏提取法测定12种多氯联苯类化合物的基质加标回收率为78.00%~104.85%,相对标准偏差为0.95%~3.64%;加速溶剂萃取法的基质加标回收率为90.00%~102.00%,相对标准偏差为0.65%~2.75%;相对于渤海湾北部海域而言,莱州湾区域只是受到轻度污染,属于低风险生态区,不会对生物产生毒副作用;而前者则处于中度污染水平,可能会对生物产生毒副作用。     

毛细管气相色谱法测定空气中硝基苯

本文选用壁涂OV—17的弹性石英毛细管柱做为分离柱,多种的苯系物不干扰测定。空气中微量的硝基苯用苯收集,富集后的硝基苯直接进色谱测定。本方法在0.05μg/ml—100μg/ml范围内呈线性,相对标准偏差4.2％,回收率大于90％,检出限3.5×10~(-3)μg。采样10.5L时,最低检出浓度为0.001mg/m~3。     

预浓缩-GC/MS测定空气中的27种ODS和HFCs

优化预浓缩仪二级冷阱温度和柱温箱初始温度,建立了预浓缩-气相色谱 /质谱联用(GC/MS)技术测定空气中27种消耗臭氧层物(ODS)和氢氟烃(HFCs)的分析方法。结果表明,27种ODS和HFCs峰形良好,分离度较好,校准曲线相对响应因子标准偏差为1.7%~15.9%,方法检出限为0.016~0.172 μg/m³。空白加标样品连续测定6次的相对标准偏差为0.9%~13.4%,回收率为70.4%~116%。基体加标样品连续测定6次的相对标准偏差为1.0%~7.8%,回收率为94.3%~108%。实验楼周边的环境空气以及实验室内部工作环境空气均检出不同浓度的ODS和HFCs,该方法适用于空气中ODS和HFCs的测定。     

化工企业废气BTEX排放及周边居民区空气暴露健康风险分析

采用气相色谱-质谱法,于2016年9月和12月对江苏省某化工企业与苯系物排放相关的废气排放口和周边居民区环境空气中苯、甲苯、邻二甲苯、间/对二甲苯、乙苯等5种典型苯系物（BTEX）的排放和区域污染特征进行分析,并开展BTEX来源分析及人体健康风险评估研究。结果表明,化工企业有机废气排放口苯质量浓度最高,超过《化学工业挥发性有机物排放标准》（DB32/3151—2016）限值,超标率达26.4%;环境空气中BTEX平均质量浓度为47.31μg/m³,BTEX检出率均超过80%,秋季和冬季BTEX质量浓度分别为72.5和22.2μg/m³,各组分质量浓度大小排序为：苯＞甲苯＞乙苯＞间/对-二甲苯＞邻-二甲苯,与废气排放口浓度大小顺序一致;与其他城市和地区进行比较,BTEX质量浓度处于中等水平。比值分析法研究BTEX来源结果表明,本地排放源是化工企业周边环境空气BTEX主要来源,一定程度上也受交通排放、化石燃料燃烧等污染源的影响。人体健康风险评估结果表明,BTEX单组分非致癌风险值（HQ）在安全范围之内,各监测点位 BTEX的HQ均＜１,非致癌风险可以忽略不计;苯的致癌风险值（R）为7.33×10^-6～7.49×10^-5,均超过10,有一定的致癌风险,且苯是I类致癌物质,应采取源头控制措施避免健康风险。     

两种前处理方法对液相色谱-电感耦合等离子体质谱法测定土壤中有机汞的比对研究

分别采用酸浸提法和碱消解法作为前处理方法,以液相色谱电感耦合等离子体质谱法(HPLC-ICP-MS)作为测定方法测定土壤中的有机汞(甲基汞、乙基汞和苯基汞),对2种前处理方法进行比对分析。结果表明,采用酸浸提法,3种有机汞的方法检出限为0.5~0.9μg/kg,甲基汞和乙基汞的加标回收率为72.4%~86.4%,相对标准偏差(RSD)均<9.3%,苯基汞的回收率均<40%,RSD为7.4%~10.2%;采用碱消解法,3种有机汞的方法检出限为0.3~0.4μg/kg,加标回收率为60.4%~106%,RSD均<8.6%。碱消解法相较于酸浸提法,具有更高的萃取效率,更好的回收率和重复性。     

气相色谱-质谱法快速筛查气态制冷剂产品中的热点管控类卤代烃

建立了利用气相色谱-质谱法快速筛查气态制冷剂产品中的10种热点管控类卤代烃的分析方法。采用气密性微量注射器对气态制冷剂样品进行取样,刺透瓶盖隔垫加入到顶空瓶中,自动进样;以GS-GasPro(多孔层开管,60 m×0.32 mm)为色谱柱,采用电子轰击离子源,全扫描模式采集。测试结果显示:目标物的体积分数在0.50%~100.00%范围内,相对响应因子的相对标准偏差(RSD)均小于20%;线性相关系数r均在0.999以上;检出限(3.143倍标准偏差)为0.01%~0.05%。对实际样品进行加标回收,回收率为79.5%~102%,测定值RSD为0.5%~3.1%。该方法可为快速、准确、批量筛查气态制冷剂产品中的多种热点管控类卤代烃提供技术支撑。     

毛细管柱气相色谱法测定空气中苯胺

本文采用带有热离子检测器的弹性石英毛细管柱做为分离柱,分离效率高,多种苯系物不干扰测定。空气中微量的苯胺用苯富集后直接进行色谱测定。本方法在0.5μg/ml—1000.0μg/ml范围内呈线性,相对标准偏差<0.8％,检出限为4.5×10(-5)μg。采样14.5L时,最低检测浓度为0.012mg/m~3。     

电子制冷预浓缩仪-气相色谱-质谱法测空气中含硫化合物

建立电子制冷预浓缩仪-气相色谱-质谱法测定空气中10种含硫化合物的方法。经考察不同采样容器、优化预处理条件、研究样品保存等获得了最佳实验条件,并通过实际样品的测定,考察了方法的适用性。结果表明:硫化氢、甲硫醇和乙硫醇3种高活性含硫化合物校准曲线线性回归系数在0.990以上,另外7种含硫化合物在0.995以上;高、中、低空白加标样品相对标准偏差均为9.5%以内,乙硫醇由于具有高活性和吸附性,低浓度空白加标回收率为63%,其余组分回收率范围为83%~110%;当进样体积为400 mL时,各目标化合物的方法检出限为0.2×10^-3~1.1×10^-3 mg/m³。分析污水处理厂无组织排放监控点的空气结果显示,该方法具有较低的检出限及较强的抗干扰能力,能较好地满足目前监测工作的要求。     

安庆市PM2.5碳质组分污染特征及来源解析

2020年3月2日—2021年2月28日在安庆市政务服务中心楼顶设置监测点,手工采集PM_2.5样品,运用多波段碳分析仪(DRI Model 2015)分析样品中碳质组分有机碳(OC)和元素碳(EC)质量浓度;利用OC/EC法、相关分析法和主成分因子分析法对PM_2.5中碳质组分的污染特征和可能来源进行解析。结果显示:安庆市手工采样期间PM_2.5平均质量浓度为(45.9±28.1)μg/m³,OC和EC的平均浓度分别为(8.0±3.4)、(1.4±0.6)μg/m³,在PM_2.5中占比为17.4%、3.1%。四季OC平均浓度分布为冬季(9.7±4.2)μg/m³ >春季(9.0±2.5)μg/m³ >秋季(8.3±2.9)μg/m³ >夏季(5.1±1.6)μg/m³,EC平均浓度分布为冬季(1.7±0.5)μg/m³ >春季(1.7±0.6)μg/m³ >秋季(1.3±0.4)μg/m³ >夏季(0.8±0.3)μg/m³。OC/EC范围为3.11~12.14,平均值为5.83,表明安庆市存在二次有机碳(SOC),SOC均值为(2.89±1.94)μg/m³,分别占OC和PM_2.5浓度的36.1%、6.3%;四季OC、EC相关性不显著,r均小于0.85,说明安庆市的碳质组分较复杂;在不同空气质量等级条件下,OC质量浓度随着污染等级的升高而逐渐升高,EC质量浓度随着污染等级升高而先升高后降低。利用主成分分析法进行来源解析发现,道路扬尘、燃煤、柴油车尾气是碳质组分的主要来源。     

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.     

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.     

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.     

Impact of Pollution Caused by Uranium Production on Soil Macrofauna

Thirty years of mining and milling activities of the Priargunsky Mining-Chemical Production Company (South-Eastern Siberia, Russia) have resulted in an enrichment of uranium in adjacent steppe soils by a factor of up to 600. A number of attendant pollutants (thorium, arsenic and heavy metals) also have high concentrations in the soil. To estimate the effects of this pollution on soil-living macroinvertebrates, pitfall trapping and core sampling were applied. The element composition of four beetle species was analysed. Soil macroinvertebrates had 3–37 times lower abundance and biodiversity at the contaminated sites compared with the control. Ground beetle communities at the contaminated sites were reduced compared to the control site. The concentrations of uranium and arsenic in beetles collected at the contaminated sites were 2–41 and 2–26 times higher, respectively, than at the control site. There is strong evidence that the contamination caused by uranium production has severe negative biological effects on important groups of the soil food web.     

Eutrophication and Sedimentation Patterns in Complete Exploitation of Water Resources Scenarios: An Example from Northwestern Semi-arid Mexico

Water requirements to supply human needs lead water stakeholders to store more water during surplus periods to fulfil the demand during – not only – scarcity periods. At the reservoirs, mostly those in semi-arid regions, water level then fluctuates extremely between rises and downward during one single year. Besides of water management implications, changes on physical, chemical and biological dynamics of these drawdown and refilling are little known yet. This paper shows the results, throughout a year, on solids, nutrients (N and P), chlorophyll-a, and sedimentation changes on the dynamics, when the former policy was applied in a reservoir from the semi-arid Northwestern Mexico. Water level sinusoidal trend impinged changes on thermal stratification and mixing, modifying nutrient cycling and primary producer responses. According to nitrogen and phosphorus concentration as well as chlorophyll-a, reservoir was mesotrophic, becoming hypertrophic during drawdown. Nutrient concentrations were high (1.22 ± 0.70 and 0.14 ± 0.12 mg P l⁻¹), increasing phosphorus and lowering N:P significantly throughout the study period, although no intensive agricultural, no urban development, neither industrial activities take place in the watershed. This suggests nutrient recycling complex mechanisms, including nutrient release from the sediment–water interface as the main nutrient pathway when shallowness, at the same time as mineralization, increases. Outflows controlled nitrogen and phosphorus availability on the ecosystem while organic matter depended on river inflows. As on other subtropical aquatic ecosystems, nitrogen limited primary productivity (Spearman correlation R = 0.75) but chlorophyll-a seasonal pattern showed an irregular trend, prompting other no-nutrient related limitants. Shallowness induced a homogeneous temporal pattern on water quality. This observed temporal variability was mainly explained statistically by changes on solids (mineral and organic), chlorophyll-a and flows (62.3%). Annual sedimentation rates of total solids ranged from 11.73 to 16.29 kg m⁻² year⁻¹ with organic matter comprising around 30%. N:P ratio on sedimentation rates were as high as could be expected in a resuspension dominated ecosystem, and spatially inverse related with N:P ratio on bottom sediments. Distance from river inlet into the reservoir reveals a marked spatial heterogeneity on solid and nitrogen sedimentation, showing the system dependence on river inflows and supporting resuspension as the main phosphorus pathway. Accretion rates (2.19 ± 0.40 cm year⁻¹) were not related to hydrological variability but decreased with the distance to the river input. Total sediment accumulation (9,895 tons km⁻² year⁻¹) denotes siltation as other serious environmental problem in reservoirs but possibly not related with operational procedures.