Assessment of carcinogenic risk due to inhalation of polycyclic aromatic hydrocarbons in PM10 from an industrial city: a Korean case-study

This study investigated the effects of meteorological conditions and spatial variations on the toxicity of polycyclic aromatic hydrocarbons (PAHs) in airborne PM(10) in Ulsan, the largest industrial city in Korea. Daily PM(10) samples were collected on quartz microfiber filters using high volume samplers located in a downtown area, a residential area and an industrial area of Ulsan during spring and summer sampling periods. Sixteen individual PAHs were extracted into a mixture solution of dichloromethane and n-hexane (1:1, v/v) in an ultrasonic bath and were analyzed using a high performance liquid chromatography system with an ultra-violet detector (HPLC-UVD). The average total PAH concentrations from the three representative sampling sites of Ulsan ranged from 16.15 to 57.12 ng/m(3) in spring and from 11.11 to 34.56 ng/m(3) in summer. The toxicity equivalent concentrations (TEQs) of the PAHs in PM(10) of Ulsan ranged from 1.82 to 13.1 ng/m(3), with an average level of 4.17 ng/m(3). The highest TEQs were found in the downtown area, which had an average value of 6.30 ng/m(3) in spring and 5.52 ng/m(3) in summer. BaP and DahA were identified as the major carcinogenic PAHs that contributed to 34.8 and 59.4% of the total carcinogenic potency of PAHs in PM(10) in Ulsan. The identified TEQs were highly correlated (r(2) = 0.73-0.90, p<0.01) with the total PAH concentrations for each area. The TEQs showed a significant correlation (p < 0.01) with the concentration of air pollutants, including PM(10), PM(2.5) and NO(2).     

Seasonal and spatial trends of suspended-particle associated polycyclic aromatic hydrocarbons in urban Shizuoka, Japan

We characterized the monthly variations of 21 polycyclic aromatic hydrocarbons (PAHs) associated with suspended particles in the city of Shizuoka, Japan, over 12 months during 2001 and 2002. The fraction of fine particles (less than 2.5 microm diameter (PM2.5)) ranged from 40 to 60% of total suspended particles over the 12 months of the study, and their concentrations ranged from 19.3 to 41.7 microg/m(3). Almost all the PAHs were found in the PM2.5 fraction, in which the summed concentration (sigma PAH) of the 21 PAHs ranged from 1.0 to 8.4 ng/m(3). PAH concentrations were elevated in the colder seasons, but the concentrations of the PM2.5 fraction of suspended particles were not. The composition of PAHs associated with PM2.5 changed little during the year of our study, indicating that seasonal sources such as heating have little effect. Factor analysis showed that three factors explain little of the seasonal variations in the sources of PAHs. Contour maps showed high concentrations of indicator PAHs for gasoline and diesel engine sources distributed along major roads and near factories on the outskirts of the city. We concluded that the contribution of vehicle exhausts to particle-associated PAHs is significant not only in the central city, but also in outer areas associated with major ring roads, and suggest that air pollution in outskirts of urban area also is concerned for health risk associated with the exposure.     

Particle-phase dry deposition and air-soil gas exchange of polycyclic aromatic hydrocarbons (PAHs) in Izmir, Turkey

Ambient air and dry deposition samples were collected at suburban and urban sites in Izmir, Turkey. Atmospheric total (particle+gas) ∑(14)PAHs concentrations were 36±39 and 144±163 ng m(-3) for suburban and urban sites, respectively. Phenanthrene was the most abundant compound at all sites, and all samples were dominated by low molecular weight PAHs. Average particulate ∑(14)PAH dry deposition fluxes were 8160±5024 and 4286±2782 ng m(-2) day(-1) and overall average particulate dry deposition velocities were 1.5±2.4 and 1.0±2.3 cm s(-1) for suburban and urban sites, respectively. Soil samples were collected at suburban site. Average soil concentration for ∑(14)PAH was 55.9±14.4 ng g(-1) dry weight. Calculated gas-phase air-soil exchange fluxes indicated that fluorene, phenanthrene, anthracene, and carbazole were deposited to soil in winter while they were volatilized in summer. Other compounds (fluoranthene-benzo[g,h,i]perylene) were deposited to soil in both periods. Annual average fluxes of PAHs representing soil to air (i.e., gas volatilization) and air to soil transfer (i.e., gas absorption, dry deposition, and wet deposition) processes were also compared. All processes were comparable for Σ(14)PAHs however their input was dominated by gas absorption. Gas absorption dominated for lower molecular weight PAHs, however dry deposition dominated for higher molecular weight PAHs. The results have suggested that for fluorene, soil and air may be approaching a steady state condition. For the remaining compounds, there was a net accumulation into the soil.     

Atmospheric concentrations, dry deposition and air-soil exchange of polycyclic aromatic hydrocarbons (PAHs) in an industrial region in Turkey

Concurrent ambient air and dry deposition samples were collected during two sampling periods at the Aliaga industrial region in Izmir, Turkey. Sigma 15-PAH (particulate+gas) concentrations ranged between 7.3 and 44.8 ng m(-3) (average+/-S.D., 25.2+/-8.8 ng m(-3)) and 10.2-71.9 ng m(-3) (44.1+/-16.6 ng m(-3)) in summer and winter, respectively. Winter/summer individual ambient PAH concentration ratios ranged between 0.8 (acenaphthene) and 6.6 (benz[a]anthracene) indicating that wintertime concentrations were affected by residential heating emissions. In contrast to the ambient concentrations, summation operator(15)-PAH particle dry deposition fluxes were higher in summer (5792+/-3516 ng m(-2)day(-1), average+/-S.D.) than in winter (2650+/-1829 ng m(-2)day(-1)), probably due to large particles from enhanced re-suspension of polluted soil particles and road dust. Average overall dry deposition velocity of PAHs calculated using the dry deposition fluxes and particle-phase concentrations was 2.9+/-3.5 cm s(-1). summation operator(15)-PAH concentrations in soils taken from 50 points in the area ranged between 11 and 4628 microg kg(-1) in dry weight. The spatial distribution of these concentrations indicated that the urban Aliaga, steel plants, the petroleum refinery, and the petrochemical plant are the major Sigma 15-PAH sources in the area. Fugacity calculations in air and soil showed that the soil acts as a secondary source to the atmosphere for low molecular weight PAHs in summer and as a sink for the higher molecular weight ones in summer and winter.     

杭州主城区悬浮细颗粒PM_(2.5)浓度变化及其组分分析

利用杭州市区2006—2008年大气悬浮颗粒PM2.5和PM2.5-10的监测资料,研究它们的物化特征。结果表明:杭州主城区PM2.5和PM2.5-103年的平均浓度分别为0.073、0.037mg·m-3,ρ(PM2.5)/ρ(PM2.5-10)的比值为1.86。PM2.5浓度存在双峰型日变化,以9:00和18:00为峰值,日变化幅度较大,并呈现冬高、夏低的季节变化。PM2.5化学组分分析表明:PM2.5中含量最多的是有机碳,占24.4%,其次是SO42-,不同组分呈现不同的季节变化。     

室内外细粒子PM_(2.5)和总悬浮颗粒物污染水平的对比研究

为了解室内外空气颗粒物PM2.5和总悬浮颗粒物(TSP)的污染状况,自2008年3月24日～4月3日在西安交通大学学生办公室、教师办公室、化学实验室和室外同时采集PM2.5和TSP样品,对其质量浓度及无机水溶性离子组分(Na+、NH4+、K+、Mg2+、Ca2+、Cl-、NO3-和SO42-)进行了分析。结果表明,室内外PM2.5和TSP浓度都远远高于美国空气质量标准规定的35μg/m3。室内外颗粒物浓度具有相同的变化趋势,且室内总体上低于室外。室内PM2.5在TSP中所占比例在65%～85%,室外在40%左右。室内外TSP和PM2.5中二次污染离子SO42-、NO3-和NH4+占总离子质量的50%以上,主要富集在细颗粒中。NH4+、K+和Cl-在总离子中的比例均为室内大于室外,PM2.5中大于TSP。Ca2+、Mg2+主要富集在粗颗粒上,室外含量远远高于室内。     

室内PM2.5浓度标准的探讨

PM 2.5在室内颗粒物中占有很大比例,由于具有比表面积大的特点,对多种有机物具有较强的吸附能力,可以直接进入肺泡,导致年总死亡率、心肺疾病死亡率以及肺癌死亡率的增加,对人体产生全方位的影响。所以将PM 2.5纳入我国室内空气质量检测范围和评价体系是加强空气污染防治、保障人体健康的必然要求。通过分析一些国家和国际组织的PM 2.5标准、我国《环境空气质量标准》及室内PM2.5的检测标准,对我国《室内空气质量标准》中PM2.5的浓度标准值进行探讨,为室内PM 2.5浓度的控制提出明确的目标与方向。     

A wintertime study of polycyclic aromatic hydrocarbons in PM(2.5) and PM(2.5-10) in Beijing: assessment of energy structure conversion

Sixteen priority polycyclic aromatic (PAHs) in PM(2.5) and PM(2.5-10) samples collected from 20 sites in Beijing, China in December 2005 and January 2006 were analyzed to determine the composition, spatial distribution and sources. Total PAHs of PM(2.5) and PM(2.5-10) ranged from 5.2 to 1062.2 ng m(-3) and 7.6 to 759.7 ng m(-3), respectively, categorized as heavier pollution. Among five kind of functional zones involved, industrial center, commercial area and village were heavily polluted. The mean concentration of PAHs in PM(2.5) of 407 ng m(-3) was 1.67-fold of that in PM(2.5-10), which was relatively high compared to the previous studies (winter in 2001 and 2002). The most evident change was the increase of Flu, BbkF and InP, which are believed to be less harmful and related to the increasing use of clean energy. However, pollution distribution was spatially heterogeneous inside the city. The most polluted sites located in the southeast of the city. Unlike previous studies, fluoranthene was the most abundant component quantified, which could be associated with increasing use of natural gas as clean energy. Compositional analysis and principal component analysis (PCA) suggested that different kinds of combustion were the main source of the PAHs in PM, though contribution of coal was still evident.     

Gas-particle concentrations of atmospheric polycyclic aromatic hydrocarbons at an urban and a residential site in Osaka, Japan: effect of the formation of atmospherically stable layer on their temporal change

A comparative study on atmospheric polycyclic aromatic hydrocarbons (PAHs) in particulate matter and the gaseous phase was performed at an urban and a residential site in Osaka, Japan, during 2005-2006. PAH concentrations at the urban site were found to be approximately twice higher than those at the residential site. At both sites, particulate PAH concentrations increased mainly in winter while the trends of temporal change in gaseous PAH concentrations were not clearly observed. The main sources of PAHs were estimated to be local traffic, e.g., diesel engines with catalytic converter. PAH concentrations did not significantly negatively correlate with ozone concentrations and meteorological parameters. Gas-particle partitioning coefficients of representative PAHs with low molecular weight (LMW) significantly negatively correlated with ambient temperature, showing that temporal change in the LMW PAH concentrations in PM could be attributable to the shift of their gas-particle distribution caused by the change in ambient temperature. For the first time, we studied the effect of the formation of atmospherically stable layer following an increase in PAH concentrations in Japan. At the urban site, PAHs showed a significant positive correlation with potential temperature gradients, indicating that temporal variability in PAH concentrations would be dominantly controlled by the formation of atmospherically stable layer in Osaka area.     

Source apportionment of PM2.5 in Beijing in 2004

Based on measurements of fine particulate matter (PM2.5, i.e., particles with an aerodynamic diameter of 2.5 microm or less) in January and August 2004, serious air pollution persists in Beijing. The chemical analysis included organic and elemental carbon, water-soluble ions, and elemental compositions. The positive matrix factorization (PMF) method was used to apportion the PM2.5 sources. The sources contributing dominantly to PM2.5 mass concentrations are coal combustion in winter and the secondary products in summer. Furthermore, the contributions from motor vehicles, road dusts and biomass burning could not be neglected. The products of biomass burning for winter heating in the area around Beijing could enter the urban area during quasi-quiescent weather conditions. In conclusion, some effective control measures were proposed to reduce the PM2.5 pollution in Beijing.     

Characteristics of polycyclic aromatic hydrocarbons and total suspended particulate in indoor and outdoor atmosphere of a Taiwanese temple

Incense burning, a common and popular practice among many families and in most temples in Taiwan, can result in indoor pollution-related health problems. This exploratory study was aimed at characterizing human exposure to polycyclic aromatic hydrocarbons (PAHs) and total suspended particulate (TSP) inside and around a Taiwanese temple, and to compare the indoor levels with levels outside. Additionally, three types of commonly used unburned incense and incense ash were analyzed in order to evaluate the relationship between incense composition and PAH emissions.Standard methods were used to determine air concentrations of 21 PAHs and TSP inside and around a chosen temple. Indoor mean total-PAH concentration, particle-bound PAH concentration and TSP concentration were 6258 ng/m(3), 490 micro g/g and 1316 micro g/m(3), respectively; values for outdoor readings were 231 ng/m (3), 245 micro g/g and 73 micro g/m(3), for outdoors, respectively indicating PAH and TSP concentrations inside 27 and 18 times greater, respectively than outdoors. With respect to concentrations of individual PAHs (particulate+gas phase), the five highest concentrations were of acenaphthylene (AcPy) (3583 ng/m(3)), naphthalene (Nap) (1264 ng/m(3)), acenaphthene (Acp) (349 ng/m(3)), fluoranthene (FL) (243 ng/m(3)) and phenanthrene (PA) (181 ng/m(3)). Median values for indoor/outdoor (I/O) ratios of individual PAHs ranged from 5.7 to 387.9, which implied that the temple was a significant PAH source. Moreover, PAH content of the tested stick incense and ash was very low. PAH levels inside the temple were much higher than those measured in the vicinity and inside residential houses; and were in fact close to levels measured at a local traffic intersection in Tainan, Taiwan, and those in a graphite-electrode producing plant during the graphitization process. It is obvious that such substantially high concentrations of PAHs and TSP constitute a potential health hazard to people working in or visiting the temple.     

Polycyclic aromatic hydrocarbons in water,sediment, soil,and plants of the Aojiang River waterway in Wenzhou,China

The town of Shuitou was renowned as the leather capital of China because of its large-scale tanning industry, but the industry's lack of pollution controls has caused severe damage to the local water system. This study determined 15 priority polycyclic aromatic hydrocarbons (PAHs) in water, sediment, soil, and plant samples collected from Aojiang River and its estuary. The total PAHs ranged from 910 to 1520 ng/L in water samples. The total PAH in sediments were moderate to low in comparison with other rivers and estuaries in China, but the relative proportions of PAHs per million people are high when considering the population size associated with each watershed. Ratios of fluoranthene/pyrene and PAHs with low/high molecular weight suggest a petrogenic PAH origin. The PAH composition profile in soil was similar to that in sediment with 4–6 ring PAHs being dominant. The PAHs with 2–3 rings were the dominant species in plant leaves. There were no correlations between PAHs in soils and in plants, suggesting that PAHs accumulate in plant leaves through absorption from the air. The general observation of elevated PAH concentrations in all matrix suggests a possible contribution by the local leather industry on the PAH concentrations in the Aojiang watershed.     

北方地区住宅PM10污染状况及综合防治措施

分析了北方部分地区2005年前后住宅内PM10的测试数据,结果表明北方地区住宅内PM10浓度超过国内标准的比例接近1/3,超过美国现行标准的比例为87.9%;住宅内PM10浓度的平均值为119.2μg/m3,约60%住户的室内PM10浓度分布在区间75μg/m3和165μg/m3之间。简要分析了国内北方地区室内PM10超标的主要原因,并对控制室内PM10的污染提出一些建议。     

Characterization of PAHs exposure in workplace atmospheres of a sinter plant and health-risk assessment for sintering workers

This study first measured concentrations of polycyclic aromatic hydrocarbons (PAHs) in four selected workplace atmospheres, including the raw materials inlet, sintering grate, rough roll shredder and control room, and the outdoor environment of a sinter plant. Then, PAHs exposures and their resultant health-risks were assessed for sintering workers. We found that total PAH concentrations of the three selected sintering process areas were higher than that of the control room. The above results could be explained by the filtration effect of the air conditioning device installed inside the control room. PAH homologue distributions of the three selected sintering process areas were significantly different from that of the outdoor environment suggesting that PAHs found in the sintering workplace atmospheres were mainly contributed by process fugitives. Total PAH exposure levels were lower than the current permissible exposure limits, thus revealing that sintering workers are not a high risk group for long-term effects attributable to PAHs. Moreover, the lung cancer risks associated with the above PAH exposures were lower than the significant risk level defined by US Supreme Court further confirming that their exposures could be acceptable at this stage.     

Occurrence and sources of polycyclic aromatic hydrocarbons and n-alkanes in PM2.5 in the roadside environment of a major city in China

Thirty six PM_2.5 samples were collected at a roadside site of the heaviest traffic road in Qingdao, a coastal mega city in North China, from March 2004 to January 2005 to perform a detailed characterization of 16 priority polycyclic aromatic hydrocarbons (PAHs) proposed by the USEPA and n-alkanes. For PAHs, the significant increase in winter was observed with average PAH level of 32.3, 11.5, 48.9 and 263 ng m⁻³ for spring, summer, autumn and winter, respectively. The average concentrations of n-alkane in PM_2.5 at ground level were 232, 121, 309 and 369 ng m⁻³ in spring, summer, autumn, and winter, respectively. The pyrogenic PAHs were mainly from the coal burning, and the liquid fossil fuel combustion was their second contribution even at the roadside of a busy street with heavy traffic in Qingdao. Petroleum residues were the dominant source for the n-alkanes. Principal component analysis results indicated that all the measured PAHs but naphthalene and those C₁₇–C₂₆ n-alkanes could be attributed to the fossil fuel burning while long-chain n-alkanes (C₂₇–C₃₅) were mainly derived from higher plant waxes. Good correlations between PAHs and n-alkanes in summer, autumn and winter suggested that they were mainly from local sources. The poor correlation of n-alkanes and PAHs in spring could be mainly due to the shift from the space heating season to non-heating season during the sampling period. This work indicated that the roadside environment in Qingdao was more deteriorated compared with non-roadside environment in other mega cities in China.     

高效净化室内空气污染GO薄膜的制备与性能

为研究高效的空气净化材料性能,采用涂覆技术制备了不同固含量氧化石墨烯(GO)薄膜,并测试了其对室内污染物的吸附性能及薄膜综合性能。采用扫描电镜(SEM)、电子能谱(EDS)、X射线衍射(XRD)、傅里叶红外光谱(FT-IR)和拉曼光谱对薄膜的形貌、成分及结构进行表征。研究表明,本文制备的GO薄膜综合性能优异,且对颗粒污染物(PM2.5、PM10)、甲醛(HCHO)及挥发性有机物(VOCs)的去除率达到97%、97%、91%和55%。当风速为0.3 m/s、压降18 Pa时,固含量40 mg/mL的GO薄膜(PP@40GO)对PM2.5去除率为97%,且具有较高的品质因素(QF)0.1948 Pa-1。本文制备的GO薄膜具有良好的综合性能。     

夏热冬冷地区居住建筑湿环境对空调能耗的影响分析

针对夏热冬冷地区建筑湿环境气候特征,建立建筑潮湿气候界定的简便性指标——月平均相对湿度。在总结当前国内外相关规范和标准中对空气湿度标准规定的基础上,分析湿环境对居住建筑室内热舒适与空气质量的影响特征,重点分析建筑湿环境对空调能耗的影响及新风耗冷量的计算方法,并提出居住建筑全年节能运行的方式,建议该地区居住建筑宜加强对湿度指标的分析,选择与气候特征相适应的空气处理设备和通风调控方式。     

Polycyclic aromatic hydrocarbons and their oxygenated derivatives in the urban atmosphere of Athens

Ambient samples of coarse and fine organic particulate matter collected from two urban sites in the city of Athens over one warm and one cold period have been solvent-extracted and quantitatively characterized by gas chromatography–mass spectrometry for their content of polycyclic aromatic hydrocarbons (PAHs) and oxidized PAHs (oxyPAHs). Variable concentrations were observed for the two distinct monthly periods representing a cold, dry period and a summer period, relating to strong local primary emissions and to lower emissions with more stable meteorological conditions, respectively. Additionally, gaseous concentrations of selected PAHs were calculated, revealing that the relative proportions between gaseous and particle phase of individual compounds may differ significantly between summer and late winter, reflecting changes in PAH emission sources and climate conditions. In fact almost all of ΣPAHs were attributed to combustion sources (82–92%), while more than half are considered as comprising of probable human carcinogens (47–62%). Traffic was confirmed as the major contributor of PAHs when appropriate diagnostic ratios and traffic marker compounds were used. This approach also led to the estimation of diesel versus petrol contribution to the atmospheric PAH burden, using the methylphenanthrene to phenanthrene ratio. The fourteen oxygenated polycyclic compounds that were quantified had greater concentrations in the colder period. Among these compounds 9,10-phenanthrenequinone, 1-pyrenecarboxaldehyde and 9H-fluoren-9-one had the highest concentrations.     

Indoor radon concentrations in Adana, Turkey

The indoor radon concentration in Adana, Turkey was measured in living rooms of 52 houses during winter 2005 and 57 houses during summer 2005. Forty-four houses were selected for both winter and summer researches for estimating seasonal variations. Indoor radon concentrations were measured seasonally over hotter and colder 2 months over the whole year, using CR-39 passive nuclear track radon detectors. The radon concentrations were ranged from 15 to 97 Bq m(-3) on January-February 2005 for 60 d and from 5 to 70 Bq m(-3) on June-July 2005 for 60 d. The average summer concentration measured was 25.8 Bq m(-3) and the average winter concentration was 48.9 Bq m(-3) in 44 houses that observed seasonal variations. The differences between winter and summer periods were ranged from 1 to 77 Bq m(-3). The average value in both winter and summer periods is 37 Bq m(-3) in 44 houses that observed seasonal variations. This value is below the worldwide indoor radon concentration distribution of 46 Bq m(-3). The annual effective dose equivalent from (222)Rn was 0.9 mSv y(-1).     

Characterization of PAHs in the atmosphere of carbon black manufacturing workplaces

The objective of this study was set out to characterize the polycyclic aromatic hydrocarbon (PAH) content in the atmosphere of an oil furnace carbon black manufacturing plant located in southern Taiwan. A standard semi-volatile sampling train, the PS-1 sampler, was used to collect samples from eight areas, including the feedstock oil unloading, furnace, filtering/micro-pulverization, pelletizing, packaging, office/outside, office/inside, and boundary area, respectively. For each area, side-by-side static samples were collected simultaneously and a total of 16 samples were obtained. For each collected sample, the adsorbent-retained PAH content and the filter-retained PAH content were used directly to determine the concentrations of gaseous-phase PAHs and particle-bound PAHs, respectively. The gas chromatograph/mass spectrometer (GC/MS) technique was used for PAH analyses, and a total of 21 PAH species were determined. Results show the gaseous-phase PAHs accounted for only 69.2% of the total PAH content for samples collected from the packaging area, which was significantly lower than those samples collected from the rest of seven areas (ranging from 96.3 to 99.7%). The result is not so surprising since the packaging area had the highest dust concentration due to the releasing of carbon black dusts during the packaging process. In this study, we further examine the contribution of gaseous-phase PAHs to the total benzo[a]pyrene equivalent (BaP(eq)) content from the health-risk assessment view of point. It can be found the contribution of gaseous-phase PAHs to the total BaP(eq) content (63.1%) was quite comparable to the corresponding contribution to the total PAH content for samples collected from the packaging area. However, a different trend can be found for samples collected from the other seven areas, where the contributions of gaseous-phase PAHs to the total BaP(eq) content (ranging from 67.7 to 93.4%) were lower than the corresponding contributions to the total PAH content. The above results can be explained by PAH homologues that contained in both gaseous-phase and particle-bound PAHs. It was found the gaseous-phase PAHs contained higher fractions of less carcinogenic low molecular weight PAH homologues, whereas particle-bound PAHs contained higher fractions of more carcinogenic high molecular weight PAH homologues. Considering the contributions of gaseous-phase PAHs to both total PAH content and total BaP(eq) content were well above 50% for the eight studied areas, it is concluded that both particle-bound and gaseous-phase PAHs should be included for assessing the exposures of carbon black workers.