Indoor air quality assessment in child care and medical facilities in Korea

In order to characterize the status of indoor air pollution in some important facilities, a list of key criteria pollutants [particulate matter (PM(10)), carbon dioxide (CO(2)), carbon monoxide (CO), formaldehyde (HCHO), and bioaerosol] was measured from a total of 91 randomly selected sites in 18 different cities, Korea (February 2006 to December 2009). The target facilities include 43 child care facilities, 38 medical facilities, 6 elementary schools, and 4 postnatal care centers. The results showed that some air pollutants (e.g., CO and HCHO) did not exceed the recommended guideline [e.g., the Korean indoor air standard (KIAS) values of 10 ppm and 100 ppb, respectively]. However, concentration of PM(10), CO(2), and bioaerosol occasionally exceeded their respective guidelines (e.g., seven, three, and two cases). Discrete seasonalities were observed from indoor pollutants because of varying ventilation practice (e.g., summer time dominance of PM(10), HCHO, and bioaerosol or winter dominance of CO(2) and CO). However, as the concentrations of the indoor pollutants were scarcely above the recommended guideline level, more diversified approaches are desirable to diagnose the status of indoor pollution and to provide a realistic strategy for the improvement of IAQ.     

Short-term variation in air quality associated with firework events: a case study

The effect of fireworks on air quality was assessed from the ambient concentrations of various air pollutants (SO2, NO2, PM10 and TSP) during Diwali festival in Hisar city (India), in November 1999. The extensive use of fireworks was found to be related to short-term variation in air quality. During the festival the concentration of SO2 was observed to be increased approximately 10-fold at few sites, whereas the concentrations of NO2, PM10 and TSP increased 2-3 times, compared to the data collected on a typical winter day in December 1999. The maximum NO2 concentration was observed a day after the festival. The diurnal pattern of the above pollutants showed a slight increase in the night. The levels of these pollutants observed during Diwali were found to be moderately high, which can be associated with serious health impacts.     

Determination of O3, NO2, SO2, CO and PM10 measured in Belgrade urban area

O(3), NO(2), SO(2), CO and PM(10) concentrations, simultaneously determined for the first time in Belgrade urban area in the autumnal period of 2005, are presented. The obtained results display similar behaviour of SO(2), NO(2), CO, PM(10) opposite from that of O(3). The weekend effect was also investigated showing diminution of average daily concentrations of SO(2), NO(2), PM(10) and CO for 72, 40, 37 and 42% respectively, and increase of the average daily concentration of O(3) for 56%. Influence of meteorological conditions on observed concentration levels was studied, too. The observed influence of wind speed on the O(3) nightly concentration levels was analyzed pointing to the phenomena of O(3) transport during episodic measurements. To make an identification of possible pollution sources and analyse the influence of meteorological parameters on pollution levels, air back trajectories for high level concentrations episodes were calculated and analysed. A multivariate receptor modelling (Principal Component Analysis, Cluster Analysis) has been applied to a set of data in order to determine the contribution of different sources. It was found that the main principal components, extracted from the air pollution data, were related to gasoline combustion, oil combustion and ozone transport.     

Indoor air pollution levels in public buildings in Thailand and exposure assessment

Levels of pollutants including PM2.5 and PM2.5 composition (black carbon and water soluble ions), SO(2), NO(2), CO, CO(2), and BTEX (benzene, toluene, ethylbenzene, xylene) were monitored for indoor and outdoor air at a university campus and a shopping center, both located in the Northern suburb of Bangkok. Sampling was done during December 2005-February 2006 on both weekdays and weekends. At the university, indoor monitoring was done in two different air conditioned classrooms which shows the I/O ratios for all pollutants to be below 0.5-0.8 during the weekends. However, on weekdays the ratios for CO(2) and most detected BTEX were above 1.0. The concept of classroom occupancy was defined using a function of the student number in a lecture hour and the number of lecture hours per day. Classroom 2, which had a higher occupancy than classroom 1, was characterized by higher concentrations of most pollutants. PM2.5 was an exception and was higher in classroom 1 (37 microg/m(3), weekdays) as compared to classroom 2 (26 microg/m(3), weekdays) which was likely linked to the dust resuspension from the carpeted floor in the former. Monitoring was also done in the shopping mall at three different sites. Indoor pollutants levels and the I/O ratios at the shopping mall were higher than at the university. Levels of all pollutants measured at the car park, except for toluene and CO(2), were the highest. I/O ratios of the pollutants at the mall were above 1.0, which indicates the relatively higher influence of the indoor sources. However, the black carbon content in PM2.5 outdoor is higher than indoor, which suggest the important contribution from outdoor combustion sources such as the traffic. Major sources of outdoor air pollution in the areas were briefly discussed. Exposure modeling was applied using the time activity and measured pollutant concentrations to assess the exposure of different groups of people in the study areas. High exposure to PM2.5, especially for the people working in the mall, should be of health effect concern.     

Temporal and spatial variations of the quality of ambient air in the Kingdom of Bahrain during 2007

The main objective of the present investigation is to study the temporal and spatial variations of the quality of ambient air in the Kingdom of Bahrain. The non-parametric Kruskal-Wallis (KW) test showed significant spatial variations and interactions of spatial-temporal among five mobile monitoring stations for 11 air pollutants. The Mann Whitney (MW) test demonstrated the seasonality of spring over winter for the PM(10), PM(2.5), NO(2), CO and p-xylene, the seasonality of winter over spring for O(3), and no significant seasonal variation for NH(3), benzene, SO(2), toluene and H(2)S. It is concluded that emissions from automobile exhaust, industrial and developmental projects are responsible for the spatial air pollution, and that air temperature is the controlling factor for the seasonal variations.     

Chemical characteristics of aerosols and trace gas distribution over North and Central India

A field campaign on aerosol chemical properties and trace gases measurements was carried out along the Delhi-Hyderabad-Delhi road corridor (spanning about 3,200 km) in India, during February 1-29, 2004. Aerosol particles were collected on quartz and cellulose filters using high volume (PM(10)) sampler at various locations along the route (i.e., urban, semi-urban, rural, and forest areas) and have been characterized for major cations (Na(+), Ca(2+), Mg(2+), K(+), and NH (4) (+)), anions (Cl(-), NO (3)(-), and SO (4)(2-)), and heavy metals (Cu, Cd, Fe, Zn, Mn, and Pb). Simultaneously, we measured NO(2) and SO(2) gases. These species show large spatial and temporal variations. The ambient PM(10) concentration has been observed to be the highest (55 ± 4 μg m(-3)) near semi-urban areas followed by forest areas (48 ± 2 μg m(-3)) and in rural areas (44 ± 22 μg m(-3)). The concentrations of NO( x ) (NO(2)+NO) and SO(2) ranged from 16 to 69 μg m(-3) and 4 to 11 μg m(-3), respectively. Among anions, NO(3)(-) and SO(4) (2-) are the major constituents of PM(10). The urban and semi-urban sites showed enhanced concentrations of Fe, Zn, Mn, Cd, and Pb. This study provide information about atmospheric concentrations of various species in the northern to central India, which may be important for policy makers to better understand the air quality of the region.     

Analysis of Urban Atmospheric Pollution Data in the Bologna Area

Pollutant concentrations relative to the years 1993-1995 measured in the Bologna urban area by a network of automatic stations (S.A.R.A. Sistema Automatico di Rilevamento Ambientale) are analysed to estimate the typical behaviour of the pollutants, especially with regard to periodicities and meteorological dependencies and to attempt prediction for the pollutant daily concentration up to a few days using a statistically based model.The results obtained show the presence of a very significant weekly periodicity for all the analysed pollutants. A yearly periodicity has been found only for the primary pollutants analysed.The statistical prediction, using an ARMA model with meteorological variables as transfer functions, shows good predicting capabilities up to one day for carbon monoxide (CO) and sulphur dioxide (SO2) and up to two days for nitrogen dioxide (NO2).     

吐鲁番市大气污染趋势及防治措施初探

通过对吐鲁番市城市环境质量三项大气主要污染物变化趋势进行调查分析，结果表明：吐鲁番市环境空气质量呈恶化趋势，大气污染物中PM10浓度呈上升趋势，SO 2呈略微上升趋势，NO2无显著变化。 PM10浓度在冬季采暖期和春秋季（4月）较高，为防治吐鲁番市空气质量变劣，急需采取积极有效的预防措施，切实保护好吐鲁番市人民赖以生存的空气环境。     

Influence of indoor air quality (IAQ) objectives on air-conditioned offices in Hong Kong

It is costly to sample all air pollutants of a general community. Air sampling should be conducted based on a practical assessment strategy and monitoring plan. In Hong Kong, the Environmental Protection Department (HKEPD) launched an Indoor Air Quality (IAQ) certification scheme to grade workplace IAQ as 'Excellent' or 'Good' by measuring the levels of nine common indoor air pollutants, namely carbon dioxide (CO(2)), carbon monoxide (CO), respirable suspended particulates (RSP), nitrogen dioxide (NO(2)), ozone (O(3)), formaldehyde (HCHO), total volatile organic compounds (TVOC), radon (Rn), and airborne bacteria count (ABC). Although average office IAQ performance has been improved since the implementation of this certification scheme, there are still resource issues and technical difficulties. To streamline the assessment of office IAQ performance, this study proposes a simple index of IAQ benchmarks formulated in compliance with the HKEPD requirements. In particular, three of the nine listed common air pollutants were selected as the 'representatives' for the overall satisfactory IAQ. Together with the assessment results of 422 Hong Kong air-conditioned offices, the index was evaluated in terms of test sensitivity, specificity and predictive values. Proved to be feasible to describe the IAQ of some air-conditioned offices, this IAQ index would be a useful tool for policymakers, building owners and professionals to quantify IAQ performance in offices and to make decisions on resources and manpower management for efficient mitigation actions.     

Chemical trends in background air quality and the ionic composition of precipitation for the period 1980-2004 from samples collected at Valentia Observatory, Co. Kerry, Ireland

A major Irish study, based upon more than 8000 samples collected over the measurement period of 22 years, for sulfur dioxide (SO2-S), sulfate (SO4-S) and nitrogen dioxide (NO2-N) concentrations (microg m(-3)) within air, and the ionic composition of precipitation samples based on sodium (Na+), potassium (K+), magnesium (Mg2+), calcium (Ca2+), chloride (Cl-), sulfate (SO4-S), non-sea salt sulfate (nssSO4-S), ammonium (NH4-N), and nitrate (NO3-N) weighted mean concentrations (mg l(-1)), has been completed. For the air samples, the sulfur dioxide and sulfate concentrations decreased over the sampling period (1980-2004) by 75% and 45%, respectively, whereas no significant trend was observed for nitrogen dioxide. The highest concentrations for sulfur dioxide, sulfate and nitrogen dioxide were associated with wind originating from the easterly and northeasterly directions i.e. those influenced by Irish and European sources. The lowest concentrations were associated with the westerly directions i.e. for air masses originating in the North Atlantic region. This was further verified with the use of backward (back) trajectory analysis, which allowed tracing the movement of air parcels using the European Centre for Medium range Weather Forecasting (ECMWF) ERA-40 re-analysis data. High non-sea salt sulfate levels were being associated with air masses originating from Europe (easterlies) with lower levels from the Atlantic (westerlies). With the precipitation data, analysis of the non-sea salt sulfate concentrations showed a decrease by 47% since the measurements commenced.     

Analysis of the air pollution climate at a background site in the Po valley

The Po valley in northern Italy is renowned for its high air pollutant concentrations. Measurements of air pollutants from a background site in Modena, a town of 200 thousand inhabitants within the Po valley, are analysed. These comprise hourly data for CO, NO, NO(2), NO(x), and O(3), and daily gravimetric equivalent data for PM(10) from 1998-2010. The data are analysed in terms of long-term trends, annual, weekly and diurnal cycles, and auto-correlation and cross-correlation functions. CO, NO and NO(2) exhibit a strongly traffic-related pattern, with daily peaks at morning and evening rush hour and lower concentrations over the weekend. Ozone shows an annual cycle with a peak in July due to local production; notwithstanding the diurnal cycle dominated by titration by nitrogen oxide, the decreasing long term trend in NO concentration did not affect the long term trend in O(3), whose mean concentration remained steady over the sampling period. PM(10) shows a strong seasonality with higher concentration in winter and lower concentration in summer and spring. Both PM(10) and ozone show a marked weekly cycle in summer and winter respectively. Regressions of PM(10) upon NO(x) show a consistently greater intercept in winter, representing higher secondary PM(10) in the cooler months of the year. There is a seasonal pattern in primary PM(10) to NO(x) ratios, with lower values in winter and higher values in summer, but the reasons are unclear.     

Air quality of Prague: traffic as a main pollution source

Political and economical transition in the Central and Eastern Europe at the end of eighties significantly influenced all aspects of life as well as technological infrastructure. Collapse of outdated energy demanding industry and adoption of environmental legislation resulted in seeming improvements of urban environmental quality. Hand in hand with modernization the newly adopted regulations also helped to phase out low quality coal frequently used for domestic heating. However, at the same time, the number of vehicles registered in the city increased. The two processes interestingly acted as parallel but antagonistic forces. To interpret the trends in urban air quality of Prague, Czech capital, monthly averages of PM(10), SO(2), NO(2), NO, O(3) and CO concentrations from the national network of automated monitoring stations were analyzed together with long term trends in fuel consumption and number of vehicles registered in Prague within a period of 1992-2005. The results showed that concentrations of SO(2) (a pollutant strongly related to fossil fuel burning) dropped significantly during the period of concern. Similarly NO(X) and PM(10) concentrations decreased significantly in the first half of the nineties (as a result of solid fuel use drop), but remained rather stable or increased after 2000, presumably reflecting rapid increase of traffic density. In conclusion, infrastructural changes in early nineties had a strong positive effect on Prague air quality namely in the first half of the period studied, nevertheless, the current trend in concentrations of automotive exhaust related pollutants (such as PM(10), NO(X)) needs adoption of stricter measures.     

Air Quality and Monitoring Strategy in the Helsinki Metropolitan Area, Finland

The Helsinki Metropolitan Area Council (YTV) is responsible for air quality monitoring in the Helsinki area. Air quality has been monitored periodically since the late 1950s. An automatic SO2 monitoring network was constructed in 1975 and TSP measurements were added in 1978. Since then the network has been expanded and currently five automatic multicomponent stations form the basis of the network monitoring SO2, NO, NO2, CO, PM10 and O3 concentrations. Manual TSP and PM10 measurements are also conducted. Mobile monitoring units are also being used as well as special measurement campaigns. The effects of air pollution on nature are studied in bioindicator monitoring. An air quality index is used in order to inform the public of the current air quality situation. Changes in air quality are reflected in monitoring strategy. SO2 concentrations have decreased in the past two decades. Annual averages in 1995 were at or below 5 µg/m3. Traffic is the major source for pollutants even though catalytic converters have lowered traffic emissions somewhat. The highest annual average NO2 concentration at an urban site was 49 µg/m3 in 1995, and there has been no clear change in NO2 levels. There has been a decreasing trend in CO concentrations. Maximum annual TSP and PM10 averages in 1995 were 92 and 32 µg/m3, respectively. The highest average lead concentration was 0.01 µg/m3. Elevated concentrations are experienced from time to time. During the spring daily TSP and PM10 concentrations can go up to around 300 and 150 µg/m3, respectively. This is caused by resuspension mainly due to street sanding. Also a major winter NO2 episode occurred in December 1995. The highest hourly NO2 concentrations reached 400 µg/m3.     

Simultaneous determination of atmospheric sulfur and nitrogen oxides using a battery-operated portable filter pack sampler

We developed a method to analyze atmospheric SO(x) (particulate SO(4)(2-)+ gaseous SO(2)) and NO(x) (NO + NO(2)) simultaneously using a battery-operated portable filter pack sampler. NO(x) determination using a filter pack method is new. SO(x) and NO(x) were collected on a Na(2)CO(3) filter and PTIO (2-phenyl-4,4,5,5-tetramethylimidazoline-3-oxide-1-oxyl) + TEA (triethanolamine) filters (6 piled sheets), respectively. Aqueous solutions were then used to extract pollutants trapped by the filters and the resulting extracts were pre-cleaned (e.g. elimination of PTIO) and analyzed for sulfate and nitrite by ion chromatography. Recoveries of SO(2) and NO(x) from standard pollutant gases and consistency of the field data with those from other instrumental methods were examined to evaluate our method. SO(x) and NO(x) could be analyzed accurately with determination limits of 0.2 ppbv and 1.0 ppbv (as daily average concentrations), respectively. The sampler can determine SO(x) and NO(x) concentrations at mountainous or remote sites without needing an electric power supply.     

南京亚青会空气质量保障回顾性评价及启示

评价了2013年南京亚青会期间环境质量临时管控措施落实及绩效情况，分析了对改善空气质量产生的影响及存在的主要问题。结果表明：南京亚青会空气质量保障临时管控措施落实情况较好，空气质量保持良好。环比7月份，8月份减排 SO2、NOx、颗粒物分别达到715，528与2029 t。环比上年同期，2013年8月份 SO2、NO2、PM10与 PM2．5浓度分别下降22．2％，26．8％，18％与11．6％。企业停、限产优势在于能协同控制多种污染物，但成本较高，操作难度大；工地停工控制一次颗粒物非常有效，且易于操作。最后总结了亚青会保障存在的问题及成功经验，并提出青奥会空气质量保障对策建议。     

不同模式版本对长三角区域大气污染物模拟结果对比评估

选取2015年1、4、7、10月(分别代表冬、春、夏、秋4季),应用CMAQv4.7.1和CMAQv5.1模式模拟长三角区域的空气质量,对比了NO2、SO2、O3、PM2.54个常规污染物的模拟结果,表明CMAQv5.1对NO2、SO2和PM2.5的模拟效果优于CMAQv4.7.1,而CMAQv4.7.1的O3模拟效果优于CMAQv5.1;CMAQv5.1的NO2模拟值更接近地面观测值,比起不同版本的化学机制对NO2模拟效果的影响,NO2的模拟偏差受排放高估的影响更大;2个版本SO2的模拟值差距较小,且都与地面观测值之间差异较小;CMAQv5.1 PM2.5的模拟值比CMAQv4.7.1更接近观测值,气溶胶模块机制的更新(例如新增细分的PM2.5模式物种和部分二次有机气溶胶生成机制的改进等)对PM2.5模拟效果的改善显著;CMAQv5.1的O3模拟值比CMAQv4.7.1高,CMAQv5.1的O3模拟值在O3观测值的高值时段更接近观测值,而CMAQv4.7.1的O3模拟值在低值时段更接近观测值,CMAQv5.1在日最大8小时平均(MDA8)O3观测浓度超标日的O3模拟效果相比CMAQv4.7.1有一定程度的改善,但在非超标日模拟效果变差,CMAQv5.1的O3模拟效果总体相比CMAQv4.7.1并未得到有效提升。提出,未来针对低值时段和低值区域的O3模拟机制的改进将进一步提升O3模拟效果。     

Mann–Kendall trend of pollutants,temperature and humidity over an urban station of India with forecast verification using different ARIMA models

The purpose of the present research is to identify the trends in the concentrations of few atmospheric pollutants and meteorological parameters over an urban station Kolkata (22° 32′ N; 88° 20′ E), India, during the period from 2002 to 2011 and subsequently develop models for precise forecast of the concentration of the pollutants and the meteorological parameters over the station Kolkata. The pollutants considered in this study are sulphur dioxide (SO₂), nitrogen dioxide (NO₂), particulates of size 10-μm diameters (PM₁₀), carbon monoxide (CO) and tropospheric ozone (O3). The meteorological parameters considered are the surface temperature and relative humidity. The Mann–Kendall, non-parametric statistical analysis is implemented to observe the trends in the data series of the selected parameters. A time series approach with autoregressive integrated moving average (ARIMA) modelling is used to provide daily forecast of the parameters with precision. ARIMA models of different categories; ARIMA (1, 1, 1), ARIMA (0, 2, 2) and ARIMA (2, 1, 2) are considered and the skill of each model is estimated and compared in forecasting the concentration of the atmospheric pollutants and meteorological parameters. The results of the study reveal that the ARIMA (0, 2, 2) is the best statistical model for forecasting the daily concentration of pollutants as well as the meteorological parameters over Kolkata. The result is validated with the observation of 2012.     

Influence of aerosol spectrum and air pollutants on fog formation in urban environment of megacity Delhi, India

Urban areas are facing increasing fog frequencies that may result due to increased air pollution emanating from variety of sources. The increased pollution levels may lead to the atmospheric reactions resulting into the formation of secondary pollutants that may also lead to increased aerosol number concentrations (ANC) in the atmosphere. This could cause enhanced water aerosols in the presence of favourable meteorological conditions and high relative humidity. This study deals with the atmospheric pollution and visibility during winter season of megacity Delhi in order to assess the relationship between the two specifically during fog episodes. Thus, this study analyses the levels of air pollutants, aerosol spectrum and meteorological conditions during one week each in the winter season of the years 2004 and 2006 in order to have an improved understanding of their role in fog formation in mega-city Delhi. More than 300 h of measurements which included episodes of dense, thick and moderate fogs of about 25 h, were studied. The measurements cover most of the accumulation mode and greater size spectrum of aerosols. Thus, the analysis is performed for the entire period, specifically, before the fog sets up, during and afterwards. In general, the relatively small variations in number concentration show larger variations in visibility prior and post dense fog formation than during dense fog episodes. Preliminary analysis of monthly averaged RSPM (Respirable Suspended particulate Matter or PM(10)) concentration values for four winter months for a period of 6 years (1996-2001) and visibility did not show a good correlation with total occurrences of fog. However, daily averaged RSPM concentration showed a good correlation with the occurrences of thick fog. Diurnal variation of Sulfur-dioxide and Nitrogen dioxide were found to have inverse relationship with visibility during fog which may be due to formation of secondary pollutants such as sulfate and to a lesser extent nitrates. Amongst, the daily averaged concentrations of all the criteria pollutants, RSPM was found to be best correlated with the fog in comparison to other pollutants.     

Spatial variability of air pollutants in the city of Taranto, Italy and its potential impact on exposure assessment

Epidemiological studies typically use monitored air pollution data from a single station or as averaged data from several stations to estimate population exposure. In industrialized urban areas, this approach may present critical issues due to the spatial complexities of air pollutants which are emitted by different sources. This study focused on the city of Taranto, which is one of the most highly industrialized cities in southern Italy. Epidemiological studies have revealed several critical situations in this area, in terms of mortality excess and short-term health effects of air pollution. The aims of this paper are to study the variability of air pollutants in the city of Taranto and to interpret the results in relation to the applicability of the data in assessing population exposure. Meteorological and pollution data (SO2, NO2, PM10), measured simultaneously and continuously during the period 2006–2010 in five air quality stations, were analyzed. Relative and absolute spatial concentration variations were investigated by means of statistical indexes. Results show significant differences among stations. The highest correlation between stations was observed for PM10 concentrations, while critical values were found for NO2. The worst values were observed for the SO2 series. The high values of 90th percentile of differences between pairs of monitoring sites for the three pollutants index suggest that mean concentrations differ by large amounts from site to site. The overall analysis supports the hypothesis that various parts of the city are differently affected by the different emission sources, depending on meteorological conditions. In particular, analysis revealed that the influence of the industrial site may be primarily identified with the series of SO2 data which exhibit higher mean concentration values and positive correlations with wind intensity when the monitoring station is downwind from the industrial site. Results suggest evaluating the population exposure to air pollutants in industrialized cities by taking into account the possible zones of influence of different emission sources. More research is needed to identify an indicator, which ought to be a synthesis of several pollutants, and take into account the meteorological variables.     

2015—2017年江苏省秋、冬季空气质量状况

采用2015—2017年秋、冬季江苏省环境空气质量监测数据,从空气质量优良(达标)率、首要污染物、主要污染物浓度分析空气质量现状及特点。结果表明,江苏省秋、冬季空气质量优良(达标)率在60%左右,其中沿海地区空气质量达标率最高(71.1%),西北地区达标率最差(52.2%)。污染日的首要污染物主要为PM 2.5,占比高达91.5%。ρ(PM2.5)/ρ(PM 10)存在地区差异,江苏西北地区扬尘源贡献较大,江苏南部地区的二次颗粒物贡献更明显。ρ(NO2)/ρ(SO2)逐年持续升高,表明大气污染类型从燃煤性污染转变为复合型污染。