Results from the 1987 total exposure assessment methodology (team) study in Southern California

Volatile organic compound (VOC) levels in breath, personal air and fixed-site (indoor and outdoor) air were measured and compared for a sample of 50 individuals in the Los Angeles area of California. Comparisons were also made between seasons (winter and summer), between breath samples taken at three different times during the 24-h monitoring period, and between exposure levels of smokers and non-smokers. Personal air levels were higher than indoor air levels and indoor levels were much higher than outdoor levels. Air concentrations in the kitchen and living area were quite similar. Air and breath levels were higher in the winter than in the summer. Little difference was found between levels for the three breath sampling periods. Mean personal air levels of VOCs related to smoking were higher in individuals exposed to tobacco smoke vs those who were not exposed. The personal air levels of smokers and passive smokers (those non-smokers exposed to tobacco smoke) were not significantly different; while similar air levels were found in the kitchen and primary living area of homes with smokers.     

扩散法测定沈阳市环境空气中的二氧化氮

被动式个体采样器（passive personal sampler）是基于气体分子扩散或渗透原理,采集空气中气态或蒸汽态污染物的一种采样方法,它不使用任何电源和抽气动力,是一种无泵采样器,可连续采样,并可作为环境空气质量评价的监测。国内外开展室内被动式扩散采样器的研究和应用的文章很多,并逐步应用于室内环境空气的监测方面,特别是对人体健康的影响评价。但是,在使用中要特别注意风速对气体污染物的采样速率的影响,为此文章介绍了利用中国预防医学科学院环境卫生监测所研制的室内分子扩散采样器[1],并自制挡风筒,使分子扩散采样器暴露在一个恒定的风速环境中,排除风速对采样速率的影响,应用于室外环境监测沈阳市环境空气中的二氧化氮的方法。经实验室性能评价能够满足实验室测试的要求,并经有动力的溶液吸收管法现场对比测试,两种测试结果一致。为室外环境监测二氧化氮提供了一个经济、准确,有实用价值的采样方法。     

Indoor/outdoor relationships of airborne ionic substances: Comparison of electronic equipment room and factory environments

In previous work, the indoor and outdoor airborne concentrations and indoor surface accumulation rates of ionic substances contained in fine (<2.5) and coarse (2.5–15 μm) particles were determined for low-occupancy electronic equipment rooms. This work has now been extended to an electronic equipment manufacturing environment.Comparison of indoor and outdoor concentrations at the manufacturing facility for both fine and coarse particles show substantially different behavior from that seen for the electronic equipment rooms.As was found previously, the dominant species in fine particles are ammonium and sulfate, which closely track each other. Their indoor and outdoor concentrations also track, but the indoor/outdoor ratios are larger by a factor of 4–5 than those found for the electronic equipment rooms. Sodium shows tracking behavior similar to ammonium and sulfate and its indoor/outdoor ratio is also large. Other ions in fine particles show elevated indoor/outdoor ratios for some sampling intervals and tracking is not evident, thought it may be masked by the large fractional error associated with species with low concentrations. There is no dominant species in the coarse fraction. Sodium and chloride track each other strongly indoors and outdoors and the indoor and outdoor concentrations of each track closely. Potassium, as well as chloride, exhibit indoor/outdoor ratios that are sometimes much larger than 1.Modelling of indoor/outdoor relationships using a mass-balance model has shown that indoor concentrations can be accurately predicted from outdoor concentrations for species with no indoor sources. The model also shows that the source generation rates for fine and coarse particles indoors range from 0 to 6.6 and 2.3 to 5.8 mg min⁻¹, respectively, for a room with a volume of 6336m³.     

Urban air pollution in Brazil: Acetaldehyde and other carbonyls

We have measured ambient levels of carbonyls in three major urban areas of Brazil: Sao Paulo, Rio de Janeiro and Salvador. The most abundant carbonyls were acetaldehyde (up to 63 μg m⁻³, or 35 ppb) followed by formaldehyde (up to 42 μg m⁻³, or 34 ppb), and acetone (up to 20 ppb). Levels of 10 other aliphatic and aromatic carbonyls were in the range 0–5 ppb. Total carbonyl concentrations were in the range 11–75 ppb. Indoor levels were also measured at several locations in Salvador. High levels of acetaldehyde, 430 μg m⁻³ or 240 ppb, were measured in a highway tunnel.Using carbonyl/CO concentration ratios, mobile source emissions of carbonyls are estimated for the Sao Paulo area. Ambient levels of acetaldehyde and acetaldehyde/formaldehyde concentration ratios in Brazil are compared to those for other urban areas, and are briefly discussed in relation with the large scale use of ethanol as a vehicle fuel.     

苏州工业园区室内外颗粒物中多溴联苯醚污染特征及人体暴露水平

利用大流量主动采样技术在苏州市工业园区工厂车间、办公室、住宅区和风景区,采集PM₁₀样品,GC-MS测定PM₁₀中8种PBDEs的含量.室内PM₁₀中PBDEs总浓度范围为9.22~64.15 pg·m^-3（均值为20.93 pg·m^-3）,室外样品中PBDEs总浓度范围为1.06~8.44 pg·m^-3（均值为5.11 pg·m^-3）,室内含量显著高于室外含量.PM₁₀中∑₈PBDEs平均浓度从高到低顺序依次为工业车间、办公室、住宅区和室外大气,与其他地区室内外颗粒物含量相比,苏州室内外大气颗粒物中PBDEs都处于较低水平.室内外大气中BDE-209是最主要化合物（平均占总PBDEs的63%）,其次为BDE-99和BDE-47.车间员工、办公室员工和儿童的PBDEs日呼吸摄入剂量分别为3.75、2.78和2.60 pg·（kg·d）^-1,这表明苏州居民呼吸暴露PBDEs的潜在健康危害并不明显.     

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.     

装修房屋室内空气的污染

调查了装修后的住宅和办公室室内空气中挥发性有机物,同时对室外空气进行了调查.共检出20多种挥发性有机物.装修后室内甲醛和苯及其他苯系物含量明显高于室外.装修后室内空气甲醛质量浓度为0.1～2.4 mg/m3,在装修后短期内甲醛质量浓度更高,有时达到13.4 mg/m3;苯质量浓度为0.03～0.17 mg/m3.装修一年内甲醛、苯和苯乙烯普遍超标.卤代烃含量一般是数个μg/m3,与室外没有显著性差异.      

Comparison of annular denuder and filter pack collection of HNO3 (g), HNO2((g), SO2 (g), and particulate-phase nitrate,nitrite and sulfate in the south-west desert

During the 15 January–4 February 1986 SCENES Special Study, a comparison study was conducted to determine atmospheric HNO₃ (g), HNO₂ (g), SO₂ (g), and particle-phase nitrate, nitrite and sulfate sampled with annular diffusion denuder and filter pack sampling systems for 12-h periods. The results of the ion chromatographic analyses of the denuder and filter extracts from the annular denuder system showed that an average of 88% of the total nitrate measured was HNO₃ (g), 97% of the total nitrite was HNO₂ (g), and 91% of the total sulfur was present as SO₂ (g). Analyses of the various gas-phase species collected by replicate annular denuder systems indicated that a precision of ± 3% to ± 18% was achieved using these denuders. The good agreement in HNO₃ (g) concentrations observed between the filter pack and the denuder (r²=0.873, slope=1.06±0.03, intercept=0±3.5 nmol m⁻³) results from the fact that the majority of the atmospheric nitrate consisted of HNO₃ (g), which minimized any positive artifact in HNO₃(g) due to loss of HNO₃(g) from particles collected in the filter pack. The particulate-phase nitrate correlation between the two sampling systems was not as good (r²=0.709, slope=0.519±0.045, intercept =0±1.2 nmol m⁻³) because the lower percentage of nitrate present as the particulate species was more affected by the loss of particulate nitrate during sampling with the filter pack.     

Characteristics of airborne particles inside southern California museums

The concentrations and chemical composition of suspended particulate matter were measured in both the fine and total size modes inside and outside five southern California museums over summer and winter periods. The seasonally averaged indoor/outdoor ratios for particulate matter mass concentrations ranged from 0.16 to 0.96 for fine particles and from 0.06 to 0.53 for coarse particles, with the lower values observed for buildings with sophisticated ventilation systems which include filters for particulate matter removal. Museums with deliberate particle filtration systems showed indoor fine particle concentrations generally averaging less than 10 μg m⁻³. One museum with no environmental control system showed indoor fine particle concentrations averaging nearly 60 μg m⁻³ in winter and coarse particle concentrations in the 30–40 μg m⁻³ range. Analyses of indoor vs outdoor concentrations of major chemical species indicated that indoor sources of organic matter may exist at all sites, but that none of the other measured species appear to have major indoor sources at the museums studied. Significant fractions of the dark-colored fine elemental (black) carbon and soil dust particles present in outdoor air are able to penetrate to the indoor atmosphere of the museums studied, and may constitute a soiling hazard to works of art displayed in museums.     

Sampling of atmospheric nitrogen dioxide using triethanolamine: Interference from peroxyacetyl nitrate

Peroxyacetyl nitrate (PAN), a pollutant ubiquitous in outdoor air, is quantitatively retained on cartridges coated with triethanolamine (TEA) and is determined as nitrite by liquid chromatography with u.v. detection. PAN is therefore a severe interferent in the widely used method involving passive and active sampling on TEA-coated substrates to measure nitrogen dioxide in indoor and outdoor air.     

Sulfur dioxide,hydrogen sulfide,total reduced sulfur,chlorinated hydrocarbons and photochemical oxidants in southern California museums

Indoor and outdoor concentrations of the air pollutants ozone, NO₂, SO₂, H₂S, total reduced sulfur (TRS), peroxyacetyl nitrate (PAN), methyl chloroform and tetrachloroethylene, have been measured at three southern California museums. Indoor maxima were 175 ppb for NO₂, 77 ppb for O₃, 0.7 ppb for PAN, 1.2 ppb for C₂Cl₄, >6.3 ppb for CH₃CCl₃, 2.5 ppb for SO₂, 1.4 ppb for TRS, and 46 ppt for H₂S. Indoor levels and indoor/outdoor (I/O) ratios for the chlorinated hydrocarbons pointed out to indoor sources. Outdoor and indoor levels of SO₂ and TRS were low at all three museums, but I/O ratios for SO₂ were high and averaged 0.89. H₂S concentrations were low, 16–46 ppt at one museum and less than 6 ppt at the other two museums. I/O ratios for the air pollutants with outdoor sources (ozone, PAN and NO₂) showed substantial variations, from low values of 0.02–0.33 at locations without influx of outdoor air to high values of 0.85–0.88 at locations experiencing high influx of outdoor air. Of the 10 institutions we have surveyed in southern California to date, eight exhibit high I/O ratios, e.g. 0.60–1.00 for PAN. Of the four museums surveyed that were equipped with HVAC and chemical filtration, only two yielded the expected low I/O ratios.     

Measurement and modeling of airbone concentrations and indoor surface accumulation rates of ionic substances at Neenah,Wisconsin

The objective of this continuing investigation of indoor/outdoor/surface relationships has been to develop an accurate method for predicting and subsequently managing the accumulation rates and ultimately the effects of corrosive substance on electronic equipment surface in field and manufacturing environments. We previously reported indoor/outdoor ratios and deposition velocities for Cl⁻, SO₄²⁻, Na⁺, NH₄⁺, Mg²⁺ and Ca²⁺ associated with fine and coarse particles at telephone company switching equipment locations in Wichita (Kansas), Lubbock (Texas) and Newark (New Jersey). Using the results from these studies, a methodology was developed for predicting the average indoor surface accumulation rates of ionic substances from their outdoor concentrations.In this paper we report new results for a site at Neenah, Wisconsin. At this site detailed data on the operational status of the air handling euipment were also obtained through a permanent monitoring system. These data and the data on ionic species have been used in mass balance model that calculates indoor concentrations from outdoor concentrations. Coupling this mass balance model with the measured deposition velocities substantially improves the earlier methodology for predicting surface accumulation rates from outdoor concentrations and enables decision makers to evaluate the effects of various manipulations in critical air handling system operating variables. Informed decisions can now be made when striking a balance between energy and indoor use and indoor air quality or equipment reliability.     

The personal,indoor and outdoor concentrations of PM-10 measured in an industrial community during the winter

The concentrations of PM-10 were measured for 2 weeks in the winter of 1988 as part of the Total Human Environmental Exposure Study (THEES). Samples were taken simultaneously in a small city, Phillipsburg, NJ for outdoor and indoor microenvironments, and with personal monitors on non-smokers. There were four outdoor sites, eight indoor sites and fourteen individuals wearing personal monitors. The mean concentrations were 66, 48 and 42 μg m⁻³ for the personal, outdoor and indoor sites, respectively, with the personal samplers having 8.8% of the 24h averages above 150 μg m⁻³. The higher outdoor averages with respect to indoors were suspected to be related to more prevalent outdoor sources of coarse particles < 10 μm in diameter, and the lack of residential smokers to contribute to the indoor respirable subfraction. There was one day during the period when all the outdoor sites exceeded the 24 h PM-10 standard. Increased outdoor levels were also reflected in elevated indoor samples and the personal samples on that day. These would be a result of direct outdoor exposures and the penetration of outdoor PM-10 to the indoors.     

田湾核电站室内氯离子来源解析

根据2005~2006年江苏田湾核电站大气吸收液(AAS)和总悬浮颗粒物(TSP)中氯离子的一年数据,分析了室内外大气各种形态氯离子的分布特点及变化规律,并对过滤器性能进行了初步评价.结果表明:该站大气氯离子浓度大小依次为:室外吸收液>室内吸收液>室外TSP>室内TSP,年均值分别为28.12,19.20,4.22,0.11μg/m3.现有过滤器可以有效过滤室外总悬浮颗粒物,但对室外气体中氯离子的过滤效率仅为32%.相关性分析表明,室内外吸收液中氯离子浓度显著相关,相关性系数为0.859.因此,室内大气氯离子主要来源室外气态或微小气溶胶.     

Receptor modeling of the Antwerp aerosol

Receptor modeling, using factor analysis, was applied for the source identification and source apportionment of air particulate samples which were collected during two sampling campaigns in Antwerp, Belgium, and analyzed by particle-induced X-ray emission (PIXE) analysis. In a summer campaign (July 1986), 16 12-h samples of total aerosol were taken using conventional low volume filter equipment. In a winter campaign (February–March 1987) 120 24-h samples, consisting of 40 coarse, 40 fine and 40 total aerosol samples, were collected using a stacked filter unit and a total filter sampler. In both campaigns between three and five sources were discerned, most of which could be attributed to existing urban sources of air particulate matter. For each source, source profiles and absolute elemental contributions were calculated.     

Determination of 15 phthalate esters in air by gas-phase and particle-phase simultaneous sampling

Based on previous research, the sampling and analysis methods for phthalate esters (PAEs) were improved by increasing the sampling flow of indoor air from 1 to 4 L/min, shortening the sampling duration from 8 to 2 hr. Meanwhile, through the optimization of chromatographic conditions, the concentrations of 9 additional PAE pollutants in indoor air were measured. The optimized chromatographic conditions required a similar amount of time for analysis as before, but gave high responsivity, the capability of simultaneously distinguishing 15 kinds of PAEs, and a high level of discrimination between individual sample peaks, as well as stable peak generation. The recovery rate of all gas-phase and particle-phase samples of the 15 kinds of PAEs ranged from 91.26% to 109.42%, meeting the quantitative analysis requirements for indoor and outdoor air sampling and analysis. For the first time, investigation of the concentration levels as well as characteristics of 15 kinds of PAEs in the indoor air from four different traffic micro-environments (private vehicles, busses, taxis and subways) was carried out, along with validation of the optimized sampling and analytical method. The results show that all the 9 additional PAEs could be detected at relatively high pollution levels in the indoor air from the four traffic micro-environments. As none of the pollution levels of the 15 kinds of PAEs in the indoor air from the 4 traffic micro-environments should be neglected, it is of great significance to increase the types of PAEs able to be detected in indoor air.     

被动采样法观测研究京津冀区域大气中气态污染物

为了对京津冀区域的大气污染物进行观测,揭示污染物浓度和组分的时空分布和变化规律,深入了解区域复合型污染,从2007年12月开始使用造价低、操作简捷的被动采样方法对区域10个站点大气中的SO2、NO2、O3和NH3等主要污染物进行了监测,对被动采样方法的区域适用性进行了比较全面的评估并根据监测结果对污染物的浓度水平和区域分布进行了研究.方法适用性评估表明被动采样方法在污染较严重的京津冀区域能进行长时间采样,采样频率设定为每月1次;平行采样结果显示,SO2、NO2、O3和NH3的变异系数分别为6.4%、7.1%、4.2%和3.9%,方法表现出良好的稳定性;每月1次的被动采样浓度结果与主动采样仪器观测结果月平均值相比具有较好的一致性,SO2、NO2和O3这2种方法监测结果的相关系数达到0.91、0.88和0.93,拟合曲线斜率分别为1.25、0.98和0.93,平均相对标准偏差分别为23.3%、14.9%和8.5%,能基本满足大气采样的要求,NH3的短时监测也表明2种方法具有可比性.评估结果说明被动采样方法是一种可靠的大气污染监测方法,可用于区域污染的监测.2008年夏季京津冀区域10个站点SO2、NO2、O3和NH3的被动采样平均浓度分别(12.3±6.3)×10-9、(13.2±7.0)×10-9、(40.5±9.5)×10-9和(24.0±13.7)×10-9.浓度区域分布显示SO2和NO2在城市站点具有较高浓度,而NH3在农业站点的浓度较高,SO2、NO2和NH3的大气浓度水平明显受局地排放影响,浓度分布较直观的反应了站点的局地源排放;而O3除了背景站兴隆,在北京和天津周边的大小城市,平均浓度都在40×10-9左右,表现出区域协同污染特征.     

Field tests of a passive sampler for atmospheric ozone at California mountain forest locations

Field tests of a colorant-based ozone passive sampler have been carried out during the 1990 smog season at five mountain forest locations in California. Co-located measurements of ambient ozone were made at all field sites using the passive sampler and a reference method, ultraviolet (u.v.) photometry. The sampling duration ranged from 3 to 30 days. Nitrogen dioxide, aldehydes and the phytotoxic oxidants peroxyacetyl nitrate (PAN) and peroxypropionyl nitrate (PPN) were measured at one location to assess possible interferences. The average precision of the measurements, calculated from data for 42 sets of colocated passive samplers, was 12%. Data for all field locations could be reduced to a single equation relating color change (ΔE units) to ozone dose (units: ppb-days). This polynomial equation could be reduced to a linear equation for color changes not exceeding 8 ΔE units (equivalent to sampling durations of up to 15 days), with good agreement between field data and earlier calibration results obtained in the laboratory. Both polynomial and linear equations can be used to obtain quantitative, time-integrated measurements of ambient ozone. The performance of the passive sampler showed no dependence on changes in ambient temperature and humidity. Interferences from air pollutants other than ozone contributed a total positive bias of less than 5% to the measured ozone concentrations: 3% for NO₂, 1.3% for PAN, 0.2% for PPN, and 0.% or less for formaldehyde and acetaldehyde.     

北京某小学室内外VOC浓度及有毒害物种识别

采用美国EPA推荐的TO14/15方法定量分析了北京市某小学室内外夏季观测的空气样品,得到82种挥发性有机物（VOCs）的浓度水平及组成特征,对其中可能危害儿童健康的有毒有害物质进行了识别.结果表明,室内总VOCs浓度高于室外,烷烃是含量最丰富物种,平均占室内外空气中定量VOCs总浓度的32.8%.室内外VOCs组成相似,异戊烷、苯、甲苯、丙醛、丙烯和二氯甲烷为浓度优势物种,受到室外源的影响较大,室内的对二氯苯、环己烷及间二氯苯较为特征,前2种物质室内/室外浓度比例平均值分别为65.8和10.5,间二氯苯室内平均浓度为2.02×10^-9（体积分数）,而室外浓度低于检测限,这3种物质可能来自室内源. 1, 3-丁二烯、氯乙烯、苯和氯甲烷4种物质在学校室内、室外及儿童家中都超过1×10^-6的癌症风险值,平均风险值分别为1.3×10^-5、 6.4×10^-6、 5.1×10^-6和3.3×10^-6,小学室外、室内及儿童家中的累积癌症风险超过1×10^-6的癌症风险值24～39倍.丙烯醛未确认具有致癌性,但具有毒有害性,在室内外及儿童家中超过基准浓度13～72倍.     

Laboratory tests of KI and alkaline annular denuders

Annular denuders coated with KI and with alkaline solutions have been tested for their ability to remove atmospheric pollutants including ozone, NO₂, SO₂, formaldehyde, methyl nitrate and peroxyacetyl nitrate. Tests were carried out at flow rates of 0.4–2.0 ℓ min⁻¹, using particle-free ambient air as well as purified air to study the effect of atmospheric CO₂ on alkaline denuder performance. Denuders coated with KI were efficient in removing O₃, NO₂, SO₂ (> 95%) and PAN (84±3%) but not methyl nitrate (44%) and formaldehyde (<5%). Selective removal of PAN from NO₂, and vice versa, could be obtained with annular denuders coated with NaOH, which removed 100% PAN and ⩽15% NO₂, and with alkaline guaiacol, which removed ⩾99% NO₂ and ⩽6% PAN.