甲醇提取-吹扫捕集-气质联用法快速测定土壤中8种苯系物

采用甲醇提取-吹扫捕集的前处理方法并结合气相色谱-质谱仪来测定土壤样品中的8种苯系物。实验结果表明,8种苯系物在前处理过程中被有效提取出来并被准确定性和定量,对于低浓度样品也具有良好的实验效果。此方法的检出限为0.3～0.8μg/kg,测定下限为1.2～3.2μg/kg。加标低、中、高3种不同质量比的标准物质,经实验分析土壤中8种苯系物相对标准偏差(RSD)为2.1%～6.8%,加标回收率为91.0%～105%,与相关行业标准相比具有一定的优势。     

加压流体萃取-GC/MS法测定土壤中半挥发性有机物

采用加压流体萃取〖CD*2〗气相色谱/质谱联用法（ASE GC/MS）测定土壤中9种半挥发性有机物,分别考察萃取条件、氮吹浓缩、硅酸镁小柱净化和浓缩定容等前处理条件对半挥发性有机物测定的影响。通过优化试验条件,使方法在100 μg/L～1 000 μg/L范围内线性良好,方法检出限为0.01 mg/kg～0.04 mg/kg。土壤样品加标回收率为72.4%～954%,4次测定结果的RSD为2.1%～6.0%。将该方法应用于测定某重点行业企业用地周边土壤,除苯并（a）芘外其余8种半挥发性有机物均为未检出。     

吹扫捕集气相色谱质谱法测定土壤中挥发性有机物

建立了吹扫捕集气相色谱质谱法同时测定土壤中卤代烃类、苯系物类、氯代苯类等二十多种挥发性有机物.使用模拟土壤和实际土壤样品优化了吹扫时间、吹扫温度等参数;采用内标法绘制了校正曲线,各目标化合物5个浓度水平的响应因子的相对标准偏差均小于20%,相关系数均大于0.999;测定了方法检出限,采用2g土壤,各目标化合物方法检出限界于0.02～1.00μg/kg;对两种总有机碳含量的实际土壤样品进行了加标回收实验,回收率范围64%～123%.     

吹扫捕集-GC/MS法测定水中苯系物质量控制指标研究

采用吹扫捕集-气相色谱/质谱法,通过统计全国多家实验室的测定数据和实际样品测试两种方法,对水中苯、甲苯、乙苯、间/对二甲苯、邻二甲苯、苯乙烯和异丙苯8种苯系物的平行样测定相对偏差、空白加标回收率及实际样品加标回收率3个质控指标进行了研究,分别给出每种苯系物的质控指标评价标准,提出其平行样测定相对偏差为6.5％ ～13....     

固相萃取-LC-MS/MS测定土壤中多溴联苯醚

采用快速溶剂萃取-固相萃取-液相色谱串联质谱法（LC-MS/MS）测定土壤中8种多溴联苯醚类（PBDEs）化合物，通过优化试验条件，使方法在100 μg/L～1 000 μg/L范围内线性良好，方法检出限为085 μg/kg～125 μg/kg。不同土壤样品的8种多溴联苯醚回收率为68.6%～127%，4次测定结果的RSD为4.8%～27.6%。将该方法用于测定电子废物拆解点周边的土壤样品，结果BDE-209测定值为未检出～168 μg/kg，BDE-183为未检出～560 μg/kg，其余6种BDEs均为未检出。     

顶空-气相色谱/质谱联用法测定水和废水中8种苯系物

采用顶空进样-气相色谱/质谱联用法(HS-GC/MS)测定水和废水中苯、甲苯、乙苯、对二甲苯、间二甲苯、邻二甲苯、异丙苯、苯乙烯等8种苯系物,优化了分析条件,讨论了色谱柱极性、加热温度、平衡时间和进样次数对测定结果的影响。8种苯系物在1.00μg/L～1 000μg/L范围内线性良好,方法检出限为0.22μg/L～0.38μg/L,实际样品平行测定的相对标准偏差5.0%,加标回收率在86.0%～115%之间。     

自动顶空进样气相色谱法测定饮用水水源中低质量浓度苯系物

以《水质 苯系物的测定 顶空/气相色谱法》（HJ 1067—2019）为基础，通过选取最优的顶空加热平衡温度和优化色谱柱升温程序，建立了自动顶空进样气相色谱法测定饮用水水源中低质量浓度苯系物的方法。该方法能够实现苯系物组分分离清晰，有效提高了检测效率。采用低质量浓度的苯系物系列溶液绘制校准曲线，在0.10～2.00 μg/mL范围内获得较好的线性关系，相关系数（r）为 0.999 4～0.999 9，检出限为0.001～0.002 μg/mL，相对标准偏差为1.5%～4.5%，加标回收率为880%～980%。该方法能够满足对饮用水水源中低质量浓度苯系物准确、高效的测定要求。     

顶空气相色谱法测定水中三氯乙醛的条件控制

探讨了顶空气相色谱法测定水中三氯乙醛的条件控制，阐述了加碱量对测定结果的影响，以及加热温度过高或加热时间过长导致三氯甲烷响应值变低的原因。结果表明，在5.0 mL水样中加入0.4 mL 5 mol/L NaOH水溶液，于45 ℃条件下加热30 min，可使目标产物三氯甲烷的响应值及稳定状态达到最佳。方法在2.00 μg/L～30.0 μg/L范围内线性良好，检出限为0.5 μg/L。对三氯甲烷背景浓度较高的自来水样品的加标回收率为88.3%～105%，RSD为6.3%。     

GC-MS/MS法测定石油污染土壤中的多环芳烃

采用丙酮-正己烷混合溶液(体积比为1∶1)提取石油污染土壤样品中10种典型多环芳烃,用GC-MS/MS法测定。通过优化前处理和测定条件,使方法在0.100 mg/L～10.0 mg/L范围内线性良好,方法检出限为5.00μg/kg～15.8μg/kg。土壤样品加标回收试验6次测定结果的RSD为0.1%～16.6%,加标回收率为43.1%～109%。将该方法用于测定湖南某石化项目周边的实际土壤,结果表明该地区不同点位土壤中多环芳烃测定值为未检出～300μg/kg,在国家标准规定的范围内。     

固相净化气相色谱法测定水产品中多种有机磷农药残留

建立了水产品中8种有机磷农药残留同时测定的方法，选择乙腈提取，ENVI-C18串联PSA固相萃取柱净化，经丙酮/正己烷混合溶液（体积比1∶1）洗脱，洗脱液氮吹浓缩后采用气相色谱外标法定量。8种有机磷农药在0.050 mg/L～1.00 mg/L范围内线性良好，检出限在1.8 μg/kg～2.5 μg/kg之间，3个添加水平加标样品平行测定的相对标准偏差为1.1%～5.7%，回收率为69.8%～116%。     

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.      

An investigation on biological stability of product water generated by lab-scale and pilot-scale distillation systems

Material Disposal Area G is the primary low-levelradioactive waste disposal site at Los Alamos NationalLaboratory, New Mexico, and is adjacent to Pueblo of SanIldefonso lands. Pueblo residents and Los Alamos scientists areconcerned about radiological doses resulting from uptake of AreaG radionuclides by mule deer (Odocoileus hemionus) andRocky Mountain elk (Cervus elaphus), then consumption ofdeer and elk meat by humans. Tissue samples were collected fromdeer and elk accidentally killed near Area G and were analyzedfor ³H, ⁹⁰Sr, total U, ²³⁸Pu, ^{239, 240}Pu,²⁴¹Am, and ¹³⁷Cs. These data were used to estimatehuman doses based on meat consumption of 23 kg y^-1. Humandoses were also modeled using RESRAD, and dose rates to deer andelk were estimated with a screening model. Dose estimates tohumans from tissue consumption were 2.9 × 10^-3 mSv y^-1and 1.6 × 10^-3 mSv y^-1 from deer and elk, respectively,and RESRAD dose estimates were of the same order of magnitude. Estimated dose rates to deer and elk were 2.1 × 10^-4 mGyd^-1 and 4.7 × 10^-4 mGy d^-1, respectively. Allestimated doses were significantly less than established exposurelimits or guidelines.     

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.     

Metal concentrations in deciduous tree leaves from urban areas in Poland

Accumulation of metals in deciduous tree foliage fromurban areas in western-south Poland was monitored duringthe vegetation season of 2000 year. Concentrations of Al,Ba, Ca, Cd, Cr, Cu, Fe, Mg, Mn, Ni, Pb, Sr, Ti and Znwere measured in birch, willow, linden and maple leavesusing the ICP-AES method. Seasonal variations of metalconcentrations and their relations with sampling sitewere investigated. The most dynamic accumulation of Al,Cd, Cr, Ni and Pb was observed for examined species. Thehighest differences in element concentrations forinvestigated sites were found for Ba, Cd, Mn and Ni.Interelement correlations were investigated. In allfoliar samples synergistic relationships between Al–Crand Ca-Sr were found. Statistically significant negativecorrelations were observed only for Cd and Ti in birch leaves.     

Varying Stable Nitrogen Isotope Ratios of Different Coastal Marsh Plants and Their Relationships with Wastewater Nitrogen and Land Use in New England, USA

The stable nitrogen isotope ratios of some biota have been used as indicators of sources of anthropogenic nitrogen. In this study the relationships of the stable nitrogen isotope ratios of marsh plants, Iva frutescens (L.), Phragmites australis (Cav.) Trin ex Steud, Spartina patens (Ait.) Muhl, Spartina alterniflora Loisel, Ulva lactuca (L.), and Enteromorpha intestinalis (L.) with wastewater nitrogen and land development in New England are described. Five of the six plant species (all but U. lactuca) showed significant relationships of increasing δ ¹⁵N values with increasing wastewater nitrogen. There was a significant (P < 0.0001) downward shift in the δ ¹⁵N of S. patens (6.0 ± 0.48‰) which is mycorrhizal compared with S. alterniflora (8.5 ± 0.41‰). The downward shift in δ ¹⁵N may be caused by the assimilation of fixed nitrogen in the roots of S. patens. P. australis within sites had wide ranges of δ ¹⁵N values, evidently influenced by the type of shoreline development or buffer at the upland border. In residential areas, the presence of a vegetated buffer (n = 24 locations) significantly (P < 0.001) reduced the δ ¹⁵N (mean = 7.4 ± 0.43‰) of the P. australis compared to stands where there was no buffer (mean = 10.9 ± 1.0‰; n = 15). Among the plant species, I. frutescens located near the upland border showed the most significant (R ² = 0.64; P = 0.006) inverse relationship with the percent agricultural land in the watershed. The δ ¹⁵N of P. australis and I. frustescens is apparently an indicator of local inputs near the upland border, while the δ ¹⁵N of Spartina relates with the integrated, watershed-sea nitrogen inputs.