Characterization, identification of ambient air and road dust polycyclic aromatic hydrocarbons in central Taiwan, Taichung

The concentrations of ambient air polycyclic aromatic hydrocarbons (PAHs) were measured simultaneously in an industrial area (Taichung Industrial Park, TIP) and suburban area (Tunghai University, THU) in central Taiwan, Taichung. A total of samples were collected simultaneously at the two sites between August 2002 and March 2003. Particle-bound PAHs (p-PAHs) were collected on quartz filters and gas-phase PAHs (g-PAHs) on glass cartridges using polyurethane foam sampler, respectively. Both types of samples were extracted with dichloromethane/n-hexane mixture (50/50, v/v) for 24 h, then the extracts were subjected to gas chromatography/mass spectrometric analysis. Moreover, the roadside dust particle PAHs composition were also collected and analyzed at TIP, THU and traffic road sampling sites. The five main road lines in Taichung City were selected as traffic road sampling sites. Correlation studies between PAHs concentrations and meteorological parameters were revealed that temperature has greater effects (P>0.6) than other meteorological parameters such as wind speed, relative humidity and atmospheric pressure on g-PAHs and p-PAHs. PAHs sources were resolved by using principal component analysis and diagnostic ratios. The major sources of PAHs were combustion, traffic vehicle exhaust (diesel and gasoline engine), incinerator and industrial stationary sources at both sampling sites in central Taiwan.     

台湾台中环保公园改善规划案

台湾台中县后里乡大甲溪旁原规划设置垃圾场一座,于十余年前增设焚化炉设施以后,该垃圾堆放场既已停用,经过规划,将原有垃圾场经过填土以后,种树植花,形成一座占地23公顷的环保公园.然在规划当时,由于未深切考虑填土深度不足的问题,以至多半乔木枯死,仅剩低矮灌木与野草杂生,原先规划期望成为一座地方公园的美意完全落空,公园遭到闲置.因此本环保公园于本年(2006)重新改造规划,以RGHCM国际休憩基地规划理念,期使成为一座符合实际观光效益的休憩公园.     

Characteristic of polycyclic aromatic hydrocarbon concentrations and source identification for fine and coarse particulates at Taichung Harbor near Taiwan Strait during 2004-2005

Fine (PM(2.5)) and coarse (PM(2.5-10)) particulate concentrations of ambient air polycyclic aromatic hydrocarbons (PAHs) were measured simultaneously from February 2004 to January 2005 at the Taichung Harbor (TH) sampling site near Taiwan of central Taiwan. Particle-bound polycyclic aromatic hydrocarbons (PAHs) were collected on quartz filters; the collected sample was Soxhlet extracted with a dichloromethane (DCM)/n-hexane mixture (50/50, v/v) for 24 h, and then the extracts were analyzed by gas chromatography-mass spectrometry (GC-MS). The results indicated that vehicle emissions, coal combustion, incomplete combustion and pyrolysis of fuel and oil burning were the main source of PAHs near Taiwan Strait of central Taiwan. Diagnostic ratios and principal component analysis (PCA) were also used to characterize and identify PAHs emission sources in this study.     

弥异所159:台中彩虹眷村

形式 花纹、动物、佛像、鸟兽虫鱼,丰富的彩绘将小村变成了色彩的天堂,宛若童话世界.墙壁彩绘由居住在此的一位退伍老兵手工绘制,使彩虹眷村成为台中市的重要旅游景点. 空间 夕阳西下,阳光为五彩的图案添了几笔绚丽;游人如织,沉寂多年的小村再次热闹熙攘.     

Increases in ambient PCDD/F and PCB concentrations in Northern Taiwan during an Asian dust storm episode

In spring 2006, an Asian dust storm (ADS) that originated in the deserts of Mongolia and China eventually reached populated areas of East Asia, including Taiwan. The concentrations of total suspended particles (TSP), vapor/solid-phase dioxin-like compounds and metal content in atmospheric aerosols were monitored at two sampling sites in northern Taiwan during the ADS episode: one along the northern coast (Site A), and the other in Taipei city (Site B). The ADS swept across northern Taiwan from 13 March to 19 March, 2006. Data indicate that the atmospheric dibenzo-p-dioxin and dibenzofuran (PCDD/F, 32.2 to 52.5 fg-I-TEQ/m(3)) and polychlorinated biphenyl (PCB, 2.23 to 4.49 fg-TEQ(WHO)/m(3)) concentrations measured at the two sampling sites prior to the ADS episode were considerably lower than those measured in other Asian countries. However, measurements made at both sites on 13 and 18 March 2006 indicate that the atmospheric PCDD/F and PCB concentrations increased 2.5 and 3.2 times at Site A, and 2.1 and 1.9 times at Site B, respectively, during the ADS episode. The concentrations of aluminum (Al), potassium (K) and Titanium (Ti) in atmospheric aerosols were also found to increase about 2 to 5 times during this period. As no specific dioxin emission sources exist within nearly 20 km of Site A, the increase in PCDD/F and PCB concentrations observed there is likely to be related to the ADS from mainland China. Additionally, the amount of PCDD/Fs bound to suspended particles increased from 257-259 to 339-512 pg-I-TEQ/g-TSP during the ADS episode. The distribution of OCDD congener observed in Taipei city increased dramatically during the ADS episode, however, the distribution of PCB congener did not vary significantly.     

Characteristics of PM10, SO2, NO(x) and O3 in ambient air during the dust storm period in Beijing

In this study, the hourly variations of the mass concentrations of PM10, SO2, NO(x) and O3 at three sampling sites were observed in Beijing during dust storm occurrence period in April 2000. The PM2.5 samples were simultaneously collected. By comparing the hourly variations of the pollutant concentrations before, during and after dust storm event and haze pollution episode, the variation characteristics of the mass concentrations of PM10, SO2, NO(x) and O3 during dust storm events were presented. The results show that the mass concentration of PM10 reached 1500 microg m(-3) during dust storm events on April 6 and 25, 2000, which was 5-10 times that of the non-dust weather conditions, and this period of high mass concentration of PM10 lasted for about 14 h, and then the concentration level prior to the dust event was recovered in 6-h time period. Due to the strong wind, the concentrations of SO2, NO(x), NO2 and O3 during dust storm period were maintained at low levels, which was significantly different from those on non-dust storm and haze pollution conditions. A lot of coarse particles as well as a very large amount of fine particles were contained in the atmospheric particulates during dust storm period, and the concentration level of PM2.5 was comparable to that during haze pollution episode. During the dust storm period, the PM2.5 concentration was approximately 230 microg m(-3), accounting for 30% of the total PM10 mass concentration, was four times that of non-dust weather conditions, and the crustal elements constituted about 66.4% of the chemical composition of PM2.5 while sulfate and nitrate contributed much less, which was quite different from the chemical composition of PM2.5 primarily constituted by sulfate, nitrate and organics on haze pollution day.     

Changes in rainfall chemistry and airborne particulates during a period of major local industrial change

Data from a site in central Scotland were used to quantify the changes in rainfall quality from 1989 to 1998. During this period there have been major changes in industrial activities in the area, particularly the decline in local steel-making and steel-processing activities. Many element concentrations in rainfall decreased over time in parallel with the phased reduction in the activity of local pollutant sources. Trend analyses of the rainfall data identified that the most significant responses have been the lower concentrations of Ca, SO4-S and Mn. There was also a dramatic decline in the capture of airborne particulates by the interception rainfall gauges. Particulates were found to contain mainly hematite, magnetite and quartz, that is similar to what would be expected to be derived from the neighbouring steel industries. The eventual disappearance of these particulates and the responses in rainfall quality match the timescale for the decline and closure of some of the potential sources of pollutants.     

Dust storms in China: a case study of dust storm variation and dust characteristics

The paper discusses the nature of dust storms, which have inherent environmental implications. The physical, chemical and mineralogical properties of dust sediments collected in Kashi, Taklimakan desert, Kunlun mountains, Donghuang, Lanzhou, Ningxia, Xi'an, Inner Mongolia and Beijing from 1990 to 1994 were studied. The texture of most aeolian deposits ranges from silty clay to clay loam with median particle diameters (Mds) generally between 5 and 63 μm; similar to the loess of central China and the silt/fine sand in western and northern China. The dust sediments were characterized by a predominance of SiO₂ and Al₂O₃ and a high amount of K₂O with molar ratios for SiO₂/Al₂O₃ and K₂O/SiO₂ from 5.17 to 8.43 and 0.009 to 0.0368 respectively. The triple peak spectrum is the main form of mass concentration in a clear sky. In a dust storm it shows as a single peak, with quartz, feldspar, chlorite, illite, calcite and dolomite being the dominant minerals. The physical, chemical and mineralogical properties of the present atmospheric dust are similar to those of wind-blown soils in western and central China. The results suggest that aeolian deposits and the fine-grained fractions of dust sediments collected in northern China are mainly soils transported from the arid and semi-arid regions of China and Mongolia by the prevailing winds. Electronic Publication     

Trace elements in size separated atmospheric particulates at trombay,Bombay, India

The results of measurements for the trace element composition of size-separated aerosols collected with an eight-stage impactor at Trombay, Bombay, India and analysed by instrumental neutron activation analysis are presented. The mass size functions and the sources of the elements analysed are discussed. The elements Sb and Hg are mainly derived from industrial emissions; over 40% of the concentration of these elements have a mean particle diameter (M.P.D.) of 1 μm for which alveolar deposition is higher than that in other parts of the lung. For Zn the abundance of particles <1 μm MMAD is high, while it is only ca. 15% or less for elements such as Fe, Sc, Co and Cr which are principally derived from soil debris.     

Suspended particulate variations and mass size distributions of incense burning at Tzu Yun Yen temple in Taiwan,Taichung

Concentrations of eight trace elements (As, Cd, Cu, Hg, Ni, Pb, Se and Zn), lindane and six groups of organic contaminants (total-chlordane, total-PCB, total-DDT, Dieldrin and Aldrin, total-butyltins, total-PAHs) at the 11 NOAA mussel watch project (MWP) sites located in North and South Carolina have been compared with the national US MWP data. Three sites from North and South Carolina had concentrations of PAHs in the upper 15th percentile on a national scale. One site had high concentrations of butyltins, and two sites had high Se concentrations. All sites from Beaufort, North Carolina, south had high As concentrations. Decreasing temporal trends were found for As, Cd, total-chlordane, DDT, PCB, and PAHs at some sites.     

Exposure to culturable airborne bioaerosols during noodle manufacturing in central Taiwan

Biological hazards associated with the manufacturing of noodles have not been well characterized in Taiwan. This is an issue that flour workers can be exposed to bioaerosols (airborne fungi and bacteria) resulting flour-induced occupational asthma or allergic diseases. This study is to survey the species and concentrations of bioaerosols at different sites within a noodle factory for one year, and to investigate the effects of environmental factors on concentrations of bioaerosols. Air samples were taken twice a day, one day each month using a MAS-100 bioaerosol sampler.Nine species of culturable fungi were identified, with the main airborne fungi being Cladosporium, Penicillium, Aspergillus spp., non-sporing isolates and yeasts. Cladosporium, Penicillium and Aspergillus were the dominant fungal isolates in the indoor and outdoor air samples. Micrococcus spp. and Staphylococcus xylosus were the dominant bacterial isolates. Peak fungal and bacterial concentrations occurred at the crushing site, with mean values of 3082 and 12,616 CFU/m³. Meanwhile, the most prevalent fungi and bacteria at the crushing site were in ranges of 2.1-1.1 μm and 1.1-0.65 μm, respectively. Significant seasonal differences in total bacterial concentration were observed at all sampling sites (?P < 0.05). Moreover, significant seasonal differences were observed for most of the fungal genera except Fusarium. Levels of Aspergillus and Rhizopus differed significantly during the two sampling times, as did levels of Micrococcus spp. and Staphylococcus arlettae.Regarding the same operation procedures, relative humidity affected fungi levels more than temperature did. However, crushing generated the highest concentration of bioaerosols among all operation procedures. Furthermore, levels of bacteria at sites fitted with ventilation systems were lower than at sites without ventilation systems, especially at the crushing site. Therefore, we recommend these workers at the crushing site wear breathing protection and improve the local ventilation systems to minimize the biological hazards.     

Indoor and outdoor PM2.5 and PM10 concentrations in the air during a dust storm

Asian dust storms (ADS) originating from the arid deserts of Mongolia and China are a well-known springtime meteorological phenomenon throughout East Asia. The ventilation systems in office utilize air from outside and therefore it is necessary to understand how these dust storms affect the concentrations of PM_2.5 and PM₁₀ in both the indoor and outdoor air. We measured dust storm pollution particles in an office building using a direct-reading instrument (PC-2 Quartz Crystal Microbalance, QCM) that measured particle size and concentration every 10 min for 1 h, three times a day. A three-fold increase in the concentrations of PM_2.5 and PM₁₀ in the indoor and outdoor air was recorded during the dust storms. After adjusting for other covariates, autoregression models indicated that PM_2.5 and PM₁₀ in the indoor air increased significantly (21.7 μg/m³ and 23.0 μg/m³ respectively) during dust storms. The ventilation systems in high-rise buildings utilize air from outside and therefore the indoor concentrations of fine and coarse particles in the air inside the buildings are significantly affected by outside air pollutants, especially during dust storms.     

The contribution from distant dust sources to the atmospheric particulate matter loadings at XiAn, China during spring

Mass concentration data for PM(10) (particulate matter, PM, less than 10 mum) combined with an air mass back-trajectory clustering technique, a potential source contribution function (PSCF) model, and a concentration-weighted trajectory (CWT) method were used to evaluate the transport pathways and sources of XiAn PM(10) in spring 2001 to 2003. Three dust source areas: "Northwesterly Sources," "Northerly Sources," and a "Loess Plateau Source" and an anthropogenic "Southerly Source" contributing to the high particulate matter concentrations at XiAn were identified using these methods. The CWT method provided more compelling information on dust sources than the PSCF model, but there are clear advantages to using multiple interpretive tools. A comparison of the major dust transport pathways shows differences for XiAn versus Beijing, with "Northwesterly Sources" more important for XiAn and arid and semi-arid regions in Mongolia more important for Beijing.     

Concentration variations of pollutants in a work week period of an office

Indoor air quality problems for a typical office space were investigated. Continuous monitoring of concentrations was carried out for CO₂, CO, formaldehyde, and total hydrocarbons. It was found that the CO₂ concentration was at times above 2000 ppm and that for CO above 14 ppm. In addition, concentration levels of formaldehyde and total hydrocarbon were found to peak at midnight and indicated non-human sources. Partial opening of windows resulted in CO₂ concentration levels of 800 ppm or below. Ventilation rate measurements using trace gas decay method found that the air change rates were well below one air change per hour.     

Influence of Asian dust storms on air quality in Taiwan

In each year, dust storms triggered by cold air masses passing through northern China and Mongolia enhance the PM10 concentration over Taiwan region during winter and spring. On average, there are four to five dust events and 6.1 dust days in a year in Taiwan. Each event lasts for 1 day or even longer. A procedure to identify a dust event is rationalized and exercised on data collected during 1994-2005. Also, a ranking method named as the dust intensity rank (DIR) is developed to distinguish the intensity of each event affecting the local air quality. About 86% of dust days belong to ranks 1 and 2. In general, poorer air quality is associated with higher ranks. Ranks 4 and 5 correspond to a PSI (Pollution Standard Index) larger than 100. Linking DIR with the popular PSI is useful for both the public and the official forecasting system. It is also useful for inter-comparison between dust influences on air quality at different downstream regions in Taiwan. Composite analyses of the temporal and spatial variation of the hourly PM10 level indicate that dust particles usually arrive 12 h before the time of the peak PM10 concentration and last for 36 h at northern Taiwan, while the time of the peak concentration at eastern or western Taiwan, due to the evolution of the synoptic weather system, is about 3-12 h later. It is noted that the increase of PM10 level at the western side of Taiwan results from a mixture of upstream Asian dust inputs and local pollutants.     

Concentration characteristics of atmospheric PCBs for urban and rural area, Korea

Mean concentrations of total PCBs (gas+particle) detected in urban and rural atmospheres were 130.41+/-62.57 pg/m(3) and 39.65+/-34.04 pg/m(3), respectively. The concentration distribution of PCB homologs in the urban and rural area decreased with increasing Cl substitutions and showed significant correlation coefficients (P>0.05) with the octanol-air partition coefficient (K(OA)) and vapor pressure, respectively. The fractions (%) of total PCBs were 28% for tri-CBs, 25% for tetra-CBs and 24% for penta-CBs in urban air and 45% for tri-CBs, 24% for tetra-CBs, and 21% for penta-CBs in rural air. The sum of those homologs was 77% for urban and 90% for rural air. Therefore, these homologs were identified as the main components of PCB homologs compared to other homologs (>penta-CBs). The Clausius-Clapeyron (CC) plot was applied to atmospheric PCB data, relating PCB partial vapor pressure (logarithm P) to inverse absolute temperature (1/T). The slopes obtained from Clausius-Clapeyron plots were -3888 (R(2)=0.75, P<0.0001) for urban and -1902 (R(2)=0.22, P<0.1) for rural air. The slope for urban air was approximately two times higher than that of rural air, possibly because the atmospheric concentration of lower molecular weight congeners in urban air may be predominantly influenced by local sources relative to rural air.     

Phosphorus-discharge hysteresis during storm events along a river catchment: the River Swale, UK

Variations in the concentration of determinands in rivers during storms often result in a hysteresis effect with different concentration during the rising and falling limb of the hydrograph. This is investigated here by measuring total phosphorus, particulate phosphorus and soluble reactive phosphorus at 3-h intervals at three points along the River Swale. Phosphorus concentration-discharge hysteresis from 10 storm events were quantified using an empirical model. The size and direction of the hysteresis loops were described by a response factor, and the slope of the loop quantified by a gradient constant. The modelled loops produced acceptable agreement with the field measurements. Hysteresis patterns for all phosphorus fractions changed markedly downstream, with predominantly anticlockwise trajectories in the upland moors (indicating a slow diffuse phosphorus delivery to the river) and clockwise in the intensively farmed lowland (indicating mobilisation of within-channel and riverbank phosphorus, and rapid inputs from field drains). The size of the hysteresis loops increased downstream, indicating an increased capacity for phosphorus storage and mobilisation within the lower catchment. During a succession of storms, lowland hysteresis loops decreased in magnitude, tending towards anticlockwise behaviour, indicating a depletion of mobile phosphorus from the river channel and margins. The modelling of hysteresis trajectories offers a convenient method of determining the relative contributions of diffuse and within-channel phosphorus sources.     

Case study of a dust storm over Hyderabad area, India: its impact on solar radiation using satellite data and ground measurements

According to the Earth Observatory dust outbreaks are considered as natural hazards, which affect the ecosystems and human life. The main objective of this study is to assess and monitor the movement of aerosols and pollutants from local or other sources, both natural and anthropogenic, using a combination of ground-based monitoring and satellite data. The turbid and polluted atmosphere in the densely-populated area of Hyderabad, India is further degradated from dust outbreaks originated from Thar desert. A dust event occurred during 10th to 11th April 2006 in the northwest region of India; its plume substantially spreaded across the downwind direction affecting the study region. Using both irradiance measurements and satellite data this dust event is investigated. The analysis shows a significant change in Aerosol Optical Depth (AOD), Aerosol Index (AI) and aerosol-particle size during the dust event. The Aerosol Optical Depth in the dusty day is about 0.2 higher than the previous non-dusty days, while the Angstr?m exponent rapidly decreases when the dust plume affected the study area. The surface PM concentrations show enhanced values during the dusty day directly influenced by the dust deposition. There is also a remarkable decrease in ground-reaching global radiation, UV erythemal (UV(ery)) and other irradiance components. The analysis suggested that the use of the diffuse-to-direct-beam ratio is the most appropriate parameter for the dust monitoring since its values at the longer wavelengths are not affected by the solar zenith angle.     

Comparison of regional and temporal trace substance distribution in bulk precipitation and atmospheric dust

Mean concentration values of PAH (1.12-benzoperylene, 3.4-benzopyrene, fluoranthene), trace metals (Zn, Pb, Cu, Fe) and γ-BHC in bulk precipitation and atmospheric particulate matter from 20 sampling stations in Bavaria (G.F.R.) were used for a multivariate regional classification of air pollution sites. For this purpose a cluster analysis with Ward's algorithm was chosen.The results of the cluster analysis show a number of pollution classes with distinct trace substance patterns.A further characterisation of these pollution classes could be reached by analysis of temporal trace substance concentrations in the atmosphere.     

Characteristics of washed-off pollutants and dynamic EMCs in parking lots and bridges during a storm

Given the importance of water quality in drinking water sources, the Korean Ministry of Environment is designing and instigating the total maximum daily load (TMDL) program for major large rivers. For the successful implementation of this program, nonpoint pollutants resulting from various land uses should be controlled. Especially, paved areas such as parking lots and bridges are stormwater intensive land uses because of their high imperviousness and high pollutant mass emissions from vehicular activity. Vehicle emissions from these paved areas include various pollutants such as heavy metals, oil, grease and particulates. This research was conducted to investigate the magnitude and nature of the stormwater emissions with the goal of quantifying stormwater pollutant concentrations and mass emission rates from a parking lot and a bridge. Two monitoring sites in Kongju city were equipped with an automatic rainfall gauge and an automatic flow meter for measuring rainfall, water quality and runoff flow. This study presents the concentration changes during storm occurrence and event mean concentrations (EMCs) in the parking lot and bridge. The first flush criteria, a new concept explaining the relationship between EMC and the first flush effect, is also suggested using dynamic EMCs.