Biogenic and anthropogenic organic compounds in eolian particulates in the East Mediterranean region—I. Occurrence and origin

Lipids of biogenic and anthropogenic origin were determined in aerosol samples, collected seasonally, in a coastal area on the north of the island of Crete. Lipid classes such as n-alkanes, hopanes, polycyclic aromatic hydrocarbons, fatty alcohols, fatty acids, fatty acid salts and α,ω-dicarboxylic acids were characterized by GC/MS and GC/FID analysis, in terms of their contents of homologous compound series. The concentrations ranged between 56 and 215 ng m⁻³ for n-alkanes, 10 and 52 ng m⁻³ for polycyclic aromatic hydrocarbons, 2 and 31 ng m⁻³ for fatty alcohols, 13 and 279 ng m⁻³ for fatty acids, 24 and 220 ng m⁻³ for fatty acid salts and 0.4 and 7.5 ng m⁻³ for α, ω-dicarboxylic acid salts. The prevailing winds were influencing the composition of the eolian particles. Generally, aerosols sampled during south wind events predominantly contained lipids originating from higher plants, while when north and northwest winds prevailed the major components were of marine origin. The absence of unsaturated fatty acids in all aerosol samples is related to the presence of α,ω-dicarboxylic acids, which are believed to be their photo-oxidation products.     

呼和浩特市大气气相和颗粒物中有机污染物的定性分析

选用聚氨基甲酸酯泡沫塑料吸附块和玻璃纤维滤膜构成的大气全态采样头,以内蒙古四子王旗摹为对照点,于冬夏两季捕集呼和浩特市（呼市）大气气相和颗粒物中的有机污染物,样品经提取分离后用色质联机,气相色谱仪,液相色谱仪鉴定出３类（烃类、芳在,酞酸酯类）近８０种有机污染物,对其中４５种进行定量分析,结果表明呼市地区属于大气有机污染物高浓度地区。     

预处理方法对海洋微藻脂肪酸萃取量及其碳稳定同位素组成的影响

为探讨不同前处理对海洋微藻脂肪酸萃取量及碳稳定同位素比值(13C)的影响,本文应用GC/MS和GC/IRMS方法,测得不同酸催化条件下产物(脂肪酸甲酯)的相对含量及单分子脂肪酸甲酯13C值,并分析比较。结果表明:对于新鲜微藻样品,盐酸催化比硫酸催化更适合于微藻中多不饱和脂肪酸的甲酯化;用硫酸催化时,微藻样品在不同预处理(A-新鲜微藻样品、B-干燥处理、C-溶剂提取)下,测得的微藻脂肪酸甲酯相对含量及13C值也存在一定差异。     

Direct comparison of cellulose and quartz fiber filters for sampling submicrometer aerosols in the marine boundary layer

Paired high-volume aerosol samples of 20–60-h duration were collected using identical Sierra Model 235 cascade impactors during a July–September 1991 research cruise in the Atlantic Ocean. Whatman 41 cellulose fiber was used for the final filter in one impactor and a quartz fiber filter was used for the final filter in the other impactor during each of 17 sampling intervals. A paired t-test of measured nonseasalt sulfate (NSS) mass concentrations indicates that the retention efficiencies of the two materials for this primarily submicrometer species are indistinguishable under the conditions of our sampling. A paired t-test of ammonium concentrations indicates slightly higher concentrations on Whatman 41, suggesting, perhaps, a positive artifact due to sorption of ammonia vapor.     

厦门冬春季大气VOCs的污染特征及臭氧生成潜势

2014年1~4月在厦门市城区和郊区开展冬春季节大气样品的采集,采用大气预浓缩系统与GC/MS联用技术定量了48种大气挥发性有机物(VOCs),对比分析了冬春季城区和郊区大气VOCs的污染特征,并利用最大增量反应活性(MIR)估算了大气VOCs的臭氧生成潜势(OFP).结果表明,冬季厦门城区和郊区大气中VOCs的平均体积分数分别为11.13×10-9和7.17×10-9,春季厦门城区和郊区大气中VOCs的平均体积分数分别为24.88×10-9和11.27×10-9,且均表现为烷烃芳香烃烯烃.通过B/T值探讨城区和郊区VOCs的来源发现,机动车和溶剂挥发是城区VOCs的主要来源,郊区VOCs除了局地源的贡献外,还受到外来污染物扩散传输的影响.城、郊区的主要VOCs包括丙烯、正丁烷、异丁烷、正戊烷、异戊烷、正己烷、苯、甲苯、乙苯和间对二甲苯,这10种组分对两地VOCs的贡献表现为春季(城区和郊区分别为62.83%和53.74%)高于冬季(城区和郊区分别为61.57%和45.83%).城、郊区VOCs的臭氧生成潜势分析显示,芳香烃的相对贡献率最大,其次是烯烃,烷烃最小.C3、C4类烯烃和苯系物是厦门城区和郊区活性较高的物种,对臭氧的贡献较大.比较观测期间城区和郊区VOCs的平均MIR值可知,郊区VOCs的活性高于城区.     

可吸入颗粒物中非晶质含量的原样XRD分析

为了获取尽可能完整的样品信息,直接利用采集的大气PM10原样进行非晶质X射线衍射(XRD)的定量分析.按照实际PM10的构成用玻璃纤维滤膜采集人为模拟大气结晶颗粒物样品,结合实验拟合得到的滤膜衍射图,推导出根据空白滤膜衍射强度计算不同样品载量时滤膜的衍射强度公式,从而消除了滤膜的基底效应的影响,并计算出实际大气样品中非晶质的衍射强度.采用无定形碳模拟大气中的非晶质,通过测定纯碳的衍射强度,得到纯碳比空白玻璃纤维滤膜的参比强度K为0.59,类比绝热法求出非晶质的质量百分比.应用该方法对北京市2010年冬季采集到的一组大气可吸入颗粒物样品进行了原样XRD分析,得出其非晶质含量分别为10.44%、13.83%、15.12%、15.88%和11.96%.     

西南丘陵区村镇典型供水水源有机物分布特征及对饮水水质的影响

以西南丘陵区村镇典型供水水源原水及其净化水为研究对象,分析了水质净化常规工艺前后其有机污染物分布特征及对饮水水质的影响.结果表明:该区域村镇供水水源属微污染水源水体,有机污染物以溶解性中小分子有机物为主,占有机物总量的50%~80%.共检测到53种共14类有机物,主要为烷烃、酯、酚、苯类物质,占有机物总量的80%~90%左右,有机酸、烯烃、醇和醛含量较小.有机物中二氯甲烷、苯酚、邻苯二甲酸二丁酯含量较高,并且出现了除草剂、食品添加剂、抗生素等污染物,如特丁津、2,6-二叔丁基对甲酚、萘啶酸等.水质净化常规工艺主要去除相对分子质量10×10~3的有机物,小分子量有机物中有机酸类去除效果较好,但烷烃、酯、酚、苯类有机物去除效果较差.     

Electrochemical measurement of carbon monoxide in breath: Interference by hydrogen

The purpose of this study was to determine the concentration of carbon monoxide (CO) in blood (COHb) and breath to demonstrate that breath hydrogen (H₂) can be a significant interferant. For this purpose, we measured blood COHb with CO-oximetry and breath CO with an electrochemical analyzer. In addition, the samples were analyzed by gas chromatography (GC). The concentration of CO in breath, collected with a Priestley tube after a 20 s breath hold, from healthy, nonsmoking adult males (n = 20) and females (n = 10) had a mean ± SD (range) of 2.6 ± 0.4 ppm (2.0–3.9), respectively, when measured by GC. However, these same samples when measured with an electrochemical (EC) analyzer showed elevated CO values of 4.7 ± 2.9 ppm (2.6–17.6). The concentration of H₂, a prominent trace gas in breath known to interfere with EC analyzers, correlated strongly with the observed EC analyzer response [EC (ppm CO) = 0.336 H₂ (ppm) + 1.93, r² = 0.98]. The EC analyzer was linear for H₂ concentrations up to 40 ppm, with a sensitivity of 0.035 V ppm⁻¹. The analyzer sensitivity to CO was 0.10 V ppm ⁻¹. Blood from this population showed COHb concentrations of 0.56 ± 0.11% (0.40–0.97), as measured by GC, but elevated values were found when measured by CO-oximeter (Ciba Corning Diagnostics Corp., Models 2500 and 270), 1.3 ± 0.2% (1.1–1.6) and 1.0 ± 0.3% (0.1–1.6), respectively. When breath CO was compared to blood COHb, only measurements by GC significantly correlated [COHb% = 0.241 CO(ppm) — 0.076, r² = 0.78]. We conclude that, relative to quantitative analysis by GC, (1) EC analyzers are susceptible to H₂ interference that cause falsely elevated CO measurements, and (2) CO-oximeters overestimate COHb concentrations in the range typical for healthy nonsmokers.     

混酸消解玻璃纤维滤筒滤膜法测定大气颗粒物中的铅

用高氯酸、硝酸和氢氟酸组成的混酸在加热的条件下消解玻璃纤维滤筒滤膜采集的铅尘样品,可基本除去滤膜中的硅。大部分除去滤筒中的硅,残留的硅酸对铅的溶出和准确测定不干扰。因此是取代索氏提取法和酸煮法的理想方法。     

Laboratory experiments on membrane filter sampling of airborne mycotoxins produced by Stachybotrys atra corda

A membrane filter method for sampling of airborne stachybotrystoxins was studied in the laboratory. Toxigenic strains of Stachybotrys atra on wallpaper, grain, hay and straw were used as toxin sources in the experiments. Air samples were collected on cellulose nitrate and polycarbonate membrane filters at air flow rates of 10–20 ℓ min⁻¹. After the filter sampling, the air was passed through methanol. The results showed that stachybotrystoxins (trichothecenes) were concentrated in airborne fungal propagules, and thus can be collected on filters. Polycarbonate filters with a pore size of 0.2 μm collected the highest percentage of toxic samples. The laboratory experiments indicated that polycarbonate filter sampling for the collection of airborne mycotoxins is a promising method for extension to field measurements.     

Analysis of vapor phase organics in air of Beijing, Langfang and Tianjin by capillary GC and GC/MS

The vapor phase organics (VPOs) in the air of Beijing, Langfang and Tianjin were detected by a capillary gas chromatography and GC/MS during the winter and the summer separately. The tentatively identified compounds include alkanes, cyclic hydrocarbons, alkenes, aromatics, acids, alcohols, aldehydes, ketones, esters, halocarbons and so on. The numbers of VPOs found are 118 in Beijing, 83 in Lang-fang and 65 in Tianjin in the winter, and 56, 39 and 72 in the summer respectively. Based on the data of some representative compounds determined quantitatively by GC and GC/MS, a profile of organic pollution in the air of the three cities is presented.     

焦化废水水质组成及其环境学与生物学特性分析

焦化废水水质的复杂性及对环境、生态影响的不确定性制约了处理水质的全面达标,且可能对后续水体造成危害.为了解焦化废水的基本物化性质、环境学特性及生物学特性,采用离子色谱、ICP/MS、GC/MS等分析手段研究了广东韶关焦化厂废水的COD、BOD、色度、氨氮、主要阴阳离子、金属成分及有机物组成等,评价了该焦化废水组分的可处理性及环境危害性,分析了焦化废水生物处理过程及可能存在的惰性有机污染物.结果表明,焦化废水构成环境危害的主要组分有COD、氨氮,挥发酚、氰化物、硫化物、氟化物及油份等,重点是有机污染物;第一类污染物在原水及外排水中的浓度是安全的;焦化废水中以酚为代表的有机物及多环、杂环化合物在水中广泛存在,经处理后仍有间甲酚、长链烷烃、苯系物、酯类、醇类、卤代烃及胺类等进入环境;造成焦化废水处理效率不高的原因是各组分之间的不协调而难以维持生物系统的正常ATP酶活,富氮缺磷,氨的生物毒害,毒性有机物对生物的抑制,Na /K 比例失衡等.因此,有毒/难降解焦化废水的处理技术须综合考虑污染物的组成、合理的工艺及排放水的生态安全性.     

Detection and Molecular Characterization of Human Noroviruses in Korean Groundwater Between 2008 and 2010

RT-PCR, nucleotide sequencing, and phylogenetic analysis were performed for genotyping and molecular characterization of noroviruses isolated from Korean groundwater. Among 160 samples collected from 80 sites between 2008 and 2010, 14 samples (8.7?%) from 12 sites were positive for noroviruses (NoVs). The percentages of NoV-positive samples in 2008, 2009, and 2010 were 22.2, 3.2, and 0?%, respectively, representing a yearly decrease. GII-positive samples (n?=?9, 5.6?%) outnumbered GI-positive samples (n?=?5, 3.1?%). The genotypes of the GI NoVs were GI.2, GI.5, and GI.6, and the genotypes of the GII NoVs were all GII.4. One sample, HM623465, was very similar to CUK-3 and CBNU2 and two GII.4 sequences isolated from the stool of Korean gastroenteritis patients. A BLASTN search revealed several nucleotide sequences highly similar to those of NoVs isolated in this study. The original isolation sources for these similar NoVs were mostly stool (n?=?731, 80.0?%) and groundwater (n?=?135, 14.8?%), and all the countries from which they were isolated were almost in Asia (96.0?%); specifically, China (n?=?192, 21.0?%), Japan (n?=?383, 41.9?%), Korea (n?=?296, 32.4?%), and other Asian countries (n?=?6, 0.7?%). These results suggest that Korean groundwater might be contaminated with NoVs from the stool of infected patients and that these NoVs in turn cause new cases of gastroenteritis through a typical fecal-oral route with region-specific circulation. Therefore, it is important to properly treat sewage, which may include waterborne viruses and manage point sources in groundwater for national health and sanitation. In addition, continuous molecular surveillance remains important for understanding circulating NoVs.     

Curauá fibers in the automobile industry – a sustainability assessment

Replacing glass fibers with natural fibers in the automobile industry can yield economic, environmental and social benefits. This article evaluates the prospective environmental impacts of automobile applications of curauá fiber (Ananas erectifolius), which nearly equates the physical properties of glass fibers. The study identified economic and social advantages of applying curauá fiber composites in car parts. Besides costing 50% less than fiber glass, the use of curauá fibers can promote regional development in the Amazon region. In order to realize significant environmental benefits, however, the curauá-based composites would have to be lighter than their glass fiber-based counterparts.     

重庆典型岩溶区地下河中溶解态正构烷烃、脂肪酸来源、迁移及转化

为阐述青木关地下河中溶解态正构烷烃和脂肪酸的来源、迁移及转化研究,2013年7月31日、10月25日分别在青木关地下河入口、天窗和出口处进行采样,并利用气相色谱-质谱联用仪(GC-MS)对样品中溶解态正构烷烃、脂肪酸的组分进行定量分析.结果表明,7月和10月样品中溶解态正构烷烃、脂肪酸的平均含量分别为1 354、667 ng·L-1和24 203、2 526ng·L-1.溶解态正构烷烃和脂肪酸的含量随地下河运移距离的增加均呈降低的趋势;基于正构烷烃分子特征参数CPI、OEP、Paq和R(ΣC≤20含量与总量的百分比)发现7月青木关地下河中溶解态正构烷烃主要来源于细菌等微生物和藻类.10月主要来源于地表水生植物,但随着地下河运移距离的增加,藻类和细菌等微生物的贡献逐渐增大;溶解态脂肪酸C16:0比例最高,结合碳峰分布特征显示7月和10月水样中,藻类和细菌等微生物为地下河中溶解态脂肪酸的主要来源.     

用同位素方法评估天津市汽油无铅化进程

用同位素技术研究和评估天津市汽油无铅化进程.采用稀酸浸出法处理天津市1994～2001年冬春季节123个玻璃纤维滤膜大气颗粒物样品,测量了大气铅浓度和同位素丰度比(²⁰⁶Pb/²⁰⁷Pb).结果表明,1994～2001年是我国汽油无铅化的重要时段,这期间大气颗粒物样品铅浓度有所下降,铅的同位素丰度比逐渐增加,表征了汽油无铅化进程中汽车尾气的贡献率减少,其他来源的贡献率上升.在汽油无铅化后,我国还应加强对铅污染的综合治理.     

Measurement of atmospheric elemental carbon: Real-time data for Los Angeles during summer 1987

Two fundamentally different techniques for measuring atmospheric elemental carbon (EC) aerosol were compared to validate the methods. One technique, photoacoustic spectroscopy, was used to measure the optical absorption (λ = 514.5 nm) of in situ atmospheric aerosol in real time. This optical absorption can be converted to EC concentration using the appropriate value of the absorption cross-section for C, so that a comparison could be made with the second technique, thermal-optical analysis of filter-collected samples, which measures the collected EC by combustion. Solvent extraction of the filter samples prior to the thermal analysis procedure was required to minimize errors due to pyrolysis of organic carbon. Excellent 1:1 correlation of atmospheric EC concentrations resulted for measurements by the photoacoustic method vs the thermal method over coincident sampling times. The linear regression gave y = 1.006 (±0.056) x+0.27 (±0.56) with r = 0.945 (n = 41), where y is the photoacoustic EC concentration and x is the thermal elemental carbon concentration, both in μg m⁻³. This data set was collected in Los Angeles as part of the Southern California Air Quality Study (SCAQS) during the summer 1987, and supplements the results of an earlier, more limited data set taken in Dearborn, MI. The diurnal variability of EC aerosol in Los Angeles during SCAQS, as determined by photoacoustic spectroscopy, is discussed.     

不同采样膜对大气颗粒物酸性测定影响的研究

颗粒物特别是酸性细粒子对人体呼吸系统具有毒性效应,且颗粒物呈酸性还会加速许多气溶胶二次组分的形成,从而影响环境和气候.因此,本文在美国环保署(EPA)制定的颗粒物酸性标准测定方法的基础上,分别采用玻璃膜、石英膜、Teflon膜和复合纤维素酯滤膜(MCE膜)在实验室中进行平行提取测定,探讨各种膜对颗粒物酸性测定的影响,确定不同条件下加入H+量与提取H+量之间的标准曲线,评价不同采样膜对颗粒物酸性测定的准确性与精密度.结果显示,Teflon膜、MCE膜、石英膜、玻璃膜用于颗粒物酸性测定,其测定的精密度和准确性分别为9.4%和7.8%、9.9%和13.0%、15.6%和18.1%、17.8%和16.1%.玻璃膜用于H+的数据测定时,由于其标准曲线的斜率变化范围大(0.745～1.048),基质碱性物质背景值高,导致测定的潜在误差最大.     

颗粒状大孔阴树脂去除有机物以及缓解膜污染的效果与机制

采用颗粒状大孔阴树脂和混凝作为微滤膜的预处理,考察它们去除有机物以及缓解膜污染的效果和机制.结果表明,树脂可有效去除中等和小分子的有机物,但对大分子有机物的去除有限;混凝可有效去除大分子有机物,但对中等和小分子有机物的去除有限.仅采用树脂作为预处理,虽然去除有机物效果较好,但缓解膜污染的作用有限;而混凝与树脂联用,不仅有效去除有机物,而且也有效缓解膜污染.     

Characterization of cytotoxicity of airborne particulates from urban areas of Lahore

A number of species (organic and inorganic) in airborne particulates cause the toxicity to living being. The potential of in vitro test methods were explored for toxicity assessment of trace toxic elements (inorganic species) present in ambient air on human being (lungs). A year long sampling of airborne particles (PM_2.5) was carried (April 2008 to March 2009) in Lahore, Pakistan. A total of thirty nine samples were collected on 47 mm Zefluor Teflon filter membranes and each was analysed to characterize for the elements: Sb, As, Be, Cd, Cr, Co, Pb, Mn, Hg using ICP-MS in water extract and total acid digestate. The samples cytotoxicity was also established using lung derived cells and MTS colorimetric assays. This generated dose response curves and IC₅₀ values for the elemental mixtures identified on the Teflon filter membrane. The results indicated that even at low concentrations airborne elemental mixtures displayed an additive toxic effect.