离子色谱法测定PM2.5中草甘膦、硫氰酸盐和高氯酸盐

正PM2.5又称细颗粒物,由于其粒径小,在大气中停留时间长,能直接通过呼吸进入并沉积在肺泡,引起心肺功能损害。PM2.5易附带微生物、重金属、有机物等有毒有害物质,在人体内不可降解,可引起人体致癌、致畸、致突变等一系列健康损害效应[1-3]。城市PM2.5的化学组成因本地区工业排放及污染源的不同而不同,了解PM2.5的污染来源和化学成分至关重要,PM2.5的危害程度又与其化学成分直接相关。根据国家大气污染(雾霾)治理总体部署,在现     

雾霾天气与化学

雾霾天气给人们的交通出行、工农业生产和身体健康都带来了严重影响。简要概述了何谓雾霾天气与PM2.5,雾霾天气的形成条件,雾霾天气中的主要化学成分,以及雾霾天气的危害与防治。     

雾霾含有毒物质20多种 雾霾天应加强自我保健

<正>雾霾中含有对人体有害的细颗粒、有毒物质达20多种,包括酸、碱、盐、胺、酚,以及尘埃、花粉、螨虫、流感病毒、结核杆菌、肺炎球菌等,其含量是普通大气水滴的几十倍。人长时间处于雾天中,可引起气管炎、喉炎、肺炎、哮喘、鼻炎、眼结膜炎及过敏性疾病等,对幼儿、青少年的生长发育和体质均有一定的影响。另外,抵抗力较差的糖尿病患者在雾霾天极有可能出现肺部及气管感染而加重病情。"PM2.5对人体的危害相对于其它颗粒物更大一些",环境工程专家侯立安指出,PM2.5具有粒径小、比表面积大、活     

超声波辅助消解-原子荧光光谱法同时测定PM_(2.5)中汞和硒

正PM2.5又称细颗粒物,是环境空气中动力学直径小于或等于2.5μm颗粒物的通称。重金属元素是PM2.5的重要组分,对其进行研究,能更好地识别污染来源、判断污染物的迁移转化途径、评估污染危害毒性,从而更有效地防治和控制环境空气污染。目前我国还没有PM2.5中重金属含量指标的相关标准,因此研究PM2.5中有害重金属的测试方法对评价可入肺颗粒物中的重金属含量指标具有重要意     

交通路口大气气溶胶的污染状况以及多环芳烃的污染特征研究

研究了城市交通路口大气气溶胶污染状况及气溶胶中多环芳烃(PAHs)的污染特征.在福州市主要交通路口之一的五四路和二环路的交叉路口采集大气中PM2.5、PM5、PM10、PM2.5~5.0、PM5~10、PM10~100及TSP.将优化的高效液相色谱编程荧光法用于各切割粒径气溶胶样品中的12种多环芳烃分析.研究结果表明:交通路口颗粒物中的飘尘(PM10)占总悬浮颗粒物(TSP)的70%;PM5占飘尘(PM10)的70%;而细粒子PM2.5占PM5的73%.交通源所产生的PAHs主要存在于细粒子PM2.5中,通过特征标志的多环芳烃的比值识别,交通路口大气颗粒物中的多环芳烃主要来源于机动车尾气排放.     

成都十里店地区冬季大气PM_(2.5)的浓度及重金属含量特征

随着我国大气污染问题日益严峻,大气环境质量愈加受到人们的关注。由于PM2.5粒径小且毒性大,现已成为大气颗粒物的研究重点。该文以成都理工大学为采样点,于2014年11月进行样品采集,并对PM2.5的重金属污染特征及其中的重金属进行评价,以加深公众对其健康危害的认识。     

PM2.5污染导致我国经济损失达68亿元

环保组织绿色和平与北大公共卫生学院联合发布《危险的呼吸PM2.5的健康危害和经济损失评估研究》报告(简称《报告》)。《报告》认为,在现有的空气质量下,2012年北京、上海、广州、西安4城市因PM2.5污染造成     

清华研究组:北京雾霾藏1300种微生物

<正>不久前,清华大学生命学院朱听研究员课题组在环境学杂志《环境科学与技术》上发表了题为《严重雾霾天气中北京PM2.5与PM10污染物中的可吸入微生物》的研究论文,报道了北京市雾霾天气中大气悬浮颗粒物的微生物组分。朱听研究组利用一套新的研究方法,首次鉴别出大气悬浮颗粒物中的微生物组分,其中包含1300多种微生物,绝大部分为非致病性的,但也含有极少量可能致病或致过敏微生物的DNA序列。据悉,朱听研究组在北京雾霾天的大气样本中,鉴定出     

美国PM2.5采样器校准方法总结

介绍美国PM2.5采样器的分类,从采样时间、滤膜称量、流量、温湿度要求和采样器性能指标等方面总结了美国PM2.5联邦参考方法采样器的校准方法。介绍美国PM2.5联邦等效方法采样器的分类及3个等级PM2.5联邦等效方法采样器的不同校准方法,以及PM2.5单分散气溶胶两种常用制备方法的制备步骤,以期促进完善我国PM2.5监测仪量值溯源体系。     

气相色谱-质谱联用技术分析大气细颗粒物对小鼠肺组织代谢轮廓的影响

建立了基于气相色谱-质谱联用技术(GC-MS)分析大气细颗粒物(PM2.5)滴注对小鼠肺组织代谢轮廓的影响的研究方法.通过分析肺组织细胞内代谢物的变化,研究不同浓度PM2.5对小鼠肺组织代谢的毒性机制.鼻腔分别滴注0、7.5、20.0和37.5 g/L的PM2.5悬液,提取肺组织胞内物质,预处理后进行GC-MS分析,结合主成分分析法(PCA)、偏最小二乘判别分析法(PLS-DA)进行数据解析,通过PLS-DA得分图可将不同PM2.5染毒浓度下的肺组织胞内物质明显区分.运用PLS-DA载荷图及模型的变量重要性因子(VIP)值,发现了7种代谢物可作为区别不同浓度PM2.5下代谢组的潜在生物标志物,分别为丙氨酸、缬氨酸、亮氨酸、鸟氨酸、延胡索酸、柠檬酸、嘌呤(p<0.01).代谢途径分析结果表明,PM2.5滴注使小鼠肺组织受到氧化损伤,氧化应激反应增强,抑制了三羧酸循环(TCA循环)及嘌呤代谢.本研究为深入解析PM2.5致毒机理提供了新的方法及理论依据.     

替代模板印迹-高效液相色谱测定空气PM2.5中的羰基化合物

以替代模板法制备了分子印迹固相萃取柱（MISPE），该柱能够有效去除空气PM2.5样品分析过程中过量的衍生剂2，4-二硝基苯肼（2，4-DNPH），并能够大幅度浓缩样品溶液，提高羰基化合物的富集效率和监测灵敏度，缩短采样时间。与高效液相色谱联用，实现了对空气PM2.5中的羰基化合物的快速检测。本研究解决了传统固相萃取材料选择性低，不能去除2，4-DNPH干扰的瓶颈问题。本方法用于研究广州市大学城早春季节雾霾天和非霾天羰基化合物水平及其来源，结果发现无论是灰霾天气还是正常天气，14种目标羰基化合物均被检出。研究发现，在污染物排放和天气因素的影响下，灰霾天气羰基化合物总量增高，尤其是异戊醛增长迅速，并且与丙醛浓度变化呈现高度正相关。通过相关性分析，证明除了光化学反应等自然因素，人类活动对广州羰基化合物水平的干扰严重，应引起重视。     

大气“霾化学”:概念提出和研究展望

大气污染是人类面临的重大环境挑战。我国大气污染具有高度的复合污染特征,其形成过程既有高强度的颗粒物均相成核现象,又有多介质非均相致霾过程,同时耦合了强的大气氧化性以及O₃污染,是不同于洛杉矶光化学烟雾和伦敦烟雾的新型“霾化学”烟雾污染。“霾化学”区别于并突破现有的理论认识,是解析我国典型多介质复合污染环境下PM_2.5成因以及PM_2.5与O₃污染间非线性复杂关系,综合研究气、液、固多介质非均相过程的大气污染化学。研究“霾化学”过程对精准控制我国乃至其他国家大气复合污染意义重大。本文提出和总结了大气“霾化学”概念,并对“霾化学”理论的完善和发展进行了展望。     

国内城市大气 PM2.5中重金属污染研究进展*

对PM2.5样品采集和消解,PM2.5中重金属检测方法、来源分析方法以及风险评价常用方法进行了简单介绍,重点介绍了国内主要城市PM2.5样品中重金属污染情况、风险评价情况及研究工作不足之处。     

Pollution characteristics of ambient PM2.5-bound PAHs and NPAHs in a typical winter time period in Taiyuan

The pollution characteristics of ambient fine particulate matter（PM2.5） containing polycyclic aromatic hydrocarbons（PAHs） and nitrated PAHs（NPAHs） in samples collected during a typical winter time period in Taiyuan of China were investigated.The obtained results revealed that the mean mass concentrations of PM2.5,SPAHs（sum of 16 PAHs） and SNPAHs（sum of 3 NPAHs） on PM2.5were161.4 mg/m3,119.8 ng/m3and 0.446 ng/m3,respectively.Diagnostic ratios of PAHs and NPAHs implied that coal consumption might be the main source of the PM2.5pollution.The measured PM2.5mass concentrations,BaP equivalent toxicity（28.632 ng/m3） and individual carcinogenicity index（3.14 10 5） were much higher than those of the recommended safety standards.     

Assessment of trace elements characteristics and human health risk of exposure to ambient PM2.5 in Hangzhou,China

A method for simultaneously determining the trace elements in particulate matter (PM) (PM2.5) by inductively coupled plasma mass spectrometry was established. The PM2.5-loaded filter samples were digested under the optimised conditions including a mixture of HNO₃–HCl–HF with ultrasonication proceeding at 70°C for 2 h. Recoveries of 90.83–103.33% were achieved for 20 elements (Co, Sr, Ag, Cd, Sb, La, Ce, Sm, W etc.) in NIST standard reference material 1648a (urban PM). PM2.5 samples were collected at urban site in Hangzhou from August 2015 to November 2015. PM2.5 concentrations of 15% sampling days exceeded the daily limitation and the mean concentrations of PM2.5 from August to November reached the 66.4% of the limitation. PM2.5 concentrations in summer were higher than that in autumn. The concentration of Zn was highest, following with Al, Pb, Mn, Cu and As. Significant enrichment was observed in Mn, Zn, Pb, Ag, V, Ni, Cu, As, Se, Hg, Co, Cd and W, which was probably induced by vehicular exhaust, oil and residual fuel combustion and industrial emissions. The daily mass concentrations of PM2.5 and elements fluctuated significantly. Rainfall could significantly reduce the concentration of Ti, Mn, Cu, Zn, As, Se, Hg, Sr, Ag, Cd, Sb, La, Ce, Sm and Pb, and the risk levels of carcinogenic elements and non-carcinogenic elements in rain day were significantly lower (43.7–81.4%) than those in non-rain day. The risk levels of Co, Cd and As could lead to adverse health outcomes through the respiratory system, which should deserve more attention, while the risk levels of Ni and non-carcinogenic elements (Hg, Mn, Cu, Zn, Pb, V) were under average risk acceptance.     

Analysis of voltammetric data for the evaluation of seasonal changes of the Ni, Cd, Pb and Cu content in atmospheric particulate PM2.5

In this paper, the preliminary results of a study on concentration of heavy metals in PM2.5 (atmospheric particles with aerodynamic diameter less than 2.5 microm) fractions of atmospheric particulate matter, sampled in Milan, are presented. This work aims to develop an electroanalytical method to analyse Pb, Cu, Cd and Ni in PM2.5 and to investigate seasonal and weekly trends in the amount of PM2.5 and its composition for considered metals. The samples have been selected within the seasons ranging from September 2002 to November 2003 so that they represent the possible seasonal changes; the samples within this period have been chosen in order to have data relevant to both working days and holidays. The determination of Cd, Pb and Cu has been carried out by Differential Pulse Anodic Stripping Voltammetry, whereas the concentration of Ni has been determined by Differential Pulse Adsorptive Cathodic Stripping Voltammetry. The concentrations of the metals in the sampled atmosphere and in the PM2.5 have been evaluated; through ANOVA possible seasonal or weekly variations in the above cited concentrations have been investigated.     

广州大气细粒子中有机碳、元素碳和水溶性有机碳的分布特征

在广州市中山大学采样点进行了为期1年的大气细粒子(PM2.5)采样,监测分析得到PM2.5及有机碳(OC)、元素碳(EC)和水溶性有机碳(WSOC)等组分的质量浓度,并进行了比较和评价分析。结果表明广州市细粒子碳污染较严重。对OC、EC和WSOC质量浓度的月变化和季节变化特征进行了讨论,并分析了原因。OC、EC浓度相关性好,表明OC、EC来源大部分相同。根据OC/EC比值,估算二次有机碳(SOC)量,结果是SOC占OC的1/3。讨论了SOC和SOC/OC比值的季节分布,结果证明SOC夏季生成比冬季多。     

A new approach for the determination of sulphur in airborne particles by HR-CS ETAAS

In this work, water and nitric acid extractable sulphur concentrations in PM2.5 fraction of urban aerosols were determined by high-resolution continuum source electrothermal molecular absorption spectrometry using most suitable CS molecular absorption band at 258.056 nm. For this purpose, the PM2.5 airborne particulates were collected on quartz filters using a high-volume sampler (500 L/min) in Istanbul (Turkey) during six months (January–June) of two consecutive years. The instrumental and experimental parameters (pyrolysis temperature, molecule formation temperature and leaching reagents) were optimised. The validity of the method for the sulphur was tested using standard reference material and the results were found to be in the uncertainty limits of the certified value.     

Size-fractionated sampling and chemical analysis by total-reflection X-ray fluorescence spectrometry of PMx in ambient air and emissions

PM 10 and PM 2.5 (PMx) have been recently introduced as new air quality standards in the EU (Council Directive 1999/30/EC) for particulate matter. Different estimates and measurements showed that the limit values for PM 10 will be exceeded at different locations in Europe, and thus measures will have to be taken to reduce PMx mass concentrations. Source apportionment has to be carried out, demanding comparable methods for ambient air and emission sampling and chemical analysis. Therefore, a special ambient-air sampler and a specially designed emission sampler have been developed. Total-reflection X-ray fluorescence analysis (TXRF) was used for multi-element analyses as a fast method with low detection limits. For ambient air measurements, a sampling unit was built, impacting particle size classes 10–2.5 μm and 2.5–1.0 μm directly onto TXRF sample carriers. An electrostatic precipitator (ESP) was used as back-up filter to also collect particles <1 μm directly onto the TXRF sample carriers. Air quality is affected by natural and anthropogenic sources, and the emissions of particles <10 μm and <2.5 μm, respectively, have to be determined to quantify their contributions to the so-called coarse (10–2.5 μm) and fine (<2.5 μm) particle modes in ambient air. For this, an in-stack particle sampling system was developed, according to the new ambient air quality standards and in view of subsequent analysis by TXRF. These newly developed samplers, in combination with TXRF analyses, were employed in field campaigns to prove the feasibility and capabilities of the approach. Ambient air data show the quantification of a wide spectrum of elements. From those concentrations, PMx ratios were calculated as an indicator for different sources of elements. Results useful for source apportionment are also the elemental day/night ratios calculated to determine local contributions to PMx mass concentrations. With regard to the emission measurements, results of mass and elemental concentrations obtained in two different processes (steel industry) show that the new PM 10/PM 2.5 cascade impactor and measurements with TXRF give characteristic fingerprints for different sources. Size-fractionated ambient air and emission sampling, together with multi-element analysis, prove to be a useful approach to derive information for source–receptor modeling, a method necessary to set up effective abatement strategies to reduce PMx mass concentrations.     

Determination of elemental and ionic compositions for diesel exhaust particles by particle induced X-ray emission and ion chromatography analysis.

The purpose of this study is to clarify the chemical characterization of PM2.5 and PM10 in diesel exhaust particles (DEP). Sampling of PM2.5 and PM10 in DEP was carried out in November 1999 using an automobile exhaust testing system at the National Traffic Safety and Environment Laboratory, with a diesel truck (engine type: direct injection, displacement: 7,961 cc, carrying weight: 2,020 kg, equivalent inertia weight: 5,600 kg) placed on a chassis dynamometer. Sampling conditions included idling, constant speed of 40 km/h, M-15 test pattern and 60%-revolution/40%-load of maximum power. Samples were collected on a polycarbonate membrane filter (Nuclepore, pore size: 0.8 microm) using a MiniVol Portable Air Sampler (Airmetrics Co., Inc.). The concentrations of several elemental and ionic species in the PM2.5 and PM10 samples were determined by particle induced X-ray emission (PIXE) and ion chromatography analysis. PIXE analysis of the PM2.5 and PM10 samples revealed 15 elements, of which Na, Mg, Si, S, Cl, Ca, Fe and Zn were found to be the major components. Ionic species were Cl-, NO2-, NO3-, SO4(2-), Na+, NH4+, K+ and Ca2+. Concentrations of elements and ionic species under the sampling condition of 60%-revolution/40%-load were highest in comparison with those of the other sampling conditions. The elemental and ionic species data were compared for PM2.5 and PM10; PM2.5 concentrations were 70% or more of PM10 concentrations for the majority of elements, and concentrations of ionic species in PM2.5 and PM10 were almost identical.