Continuous Air Quality Monitoring Stations Research Articles

Assessment and Prediction of PM2.5 in Delhi in View of Stubble Burn from Border States Using Collaborative Learning Model

Harvest scum burning in post-monsoon season in the nearby states increases air pollution levels. A thick layer of smog blankets can be seen in Delhi, India in November, the primary season of stubble burning. PM2.5 can play a major role in analyzing the stubble burning, as it has a better living time in the air. Numerous machine-learning techniques have been adopted to forecast the air quality, but none of them focuses primarily on the issues of stubble burning and its effect on Delhi’s air. In this paper, the author attempts to estimate the value of PM2.5 in Delhi, mainly due to stubble burning in neighboring states. For this, the PM2.5, PM10, NO2, CO, and SO2 data is taken into consideration for 9 ground-based continuous air quality monitoring stations in the neighboring states of Delhi for the duration of 6 months and 15 days in the calendar year of 2019. Subsequently various meteorological parameters are considered like wind speed, temperature, and relative humidity. The model used here is based on collaborative learning (stacking regression) which is trained using the out-of-folds predictions based on the complete training set, later the meta-regression is trained based on the outputs of the different regression methods in the group. The presented model is validated using different machine-learning methods, statistical measures, and the real-time stubble data of Delhi. The results show that the proposed method performs well when compared with previous methods.

Air pollution improvement and mortality rate during COVID-19 pandemic in India: global intersectional study.

This research was carried out using the open-source database system along with the continuous air quality monitoring station results from global data sets during the COVID-19 pandemic lockdown in India and the global. Our purpose of this research is to study the improvement of air quality and human mortality rates in countries worldwide during the COVID-19 pandemic lockdown. Worldwide air quality data were collected from > 12,000 continuous air quality monitoring stations on six continents covering 1000 major cities from over 100 countries. Here, we discussed the implementation of the open-source data set of basic air pollutants such as PM 2.5, NO2, temperature, relative humidity, and Air Quality Index variation during the pre-lockdown and lockdown pandemic COVID-19 in India and described the global aspect. An average concentration of PM 2.5 (145.51 μg/m3), NO2 (21.64 μg/m3), and AQI index (55.58) continuously decreased. The variation of PM 2.5, NO2, normally shows more than 25 μg/m3 every year, but during the COVID-19 lockdown period (April 2020) continuously decreased below 20 μg/m3. Similarly, the AQI index and meteorological factors such as temperature, relative humidity, and wind speed variation decreased significantly in the many countries in the world. In Asian countries, air quality improved during the national lockdown especially in the most polluted cities globally such as Beijing, Delhi, and Nanjing and also in developed cities like Madrid, New York, Paris, Seoul, Sydney, Tokyo. Furthermore, the reduction of particulate matter was in about 46%, and other gaseous pollutants during the lockdown period were observed in a 54% reduction. We are witnessing pollution reductions which add significantly to improvements in air quality. This is due to the massive decrease in the use of fossil fuel, which in turn reduces production and traffic in general. People nowadays are now willing to see a comparatively healthier world with bleached skies and natural ecosystems. This research finding demonstrates potential safety benefits associated with improving air quality and mortality rates during the COVID-19 pandemic, resulting in decreases in mortality rates in India and around the world.Electronic supplementary materialThe online version of this article (10.1007/s11869-020-00892-w) contains supplementary material, which is available to authorized users.

Performance evaluation of portable air quality measurement system using raspberry pi for remote monitoring

<span>United Nations’ Sustainable Development Goals focuses on good health and well-being for all. Air pollution becomes a huge threat to delivering on the vision of a better world and related at least to Goal 3, 7, 11, and 13. In Malaysia, air pollution index were monitored on 68 locations. The Department of Environment monitors air quality using costly continuous air quality monitoring stations (CAQMs) installed at fixed locations of highly populated and industrial areas. The objective of this paper is to develop a portable air quality measurement system which can measure particulate matters (PM) smaller than 10 and 2.5 microns, and four hazardous gasses, including carbon monoxide, sulphur dioxide, ground level ozone and nitrogen dioxide, as well as humidity and temperature. Six sensors were used and validated using several rigorous experiments. The functionality of the system was evaluated by measuring sub-API readings in areas with low and high traffic volumes. Experimental results showed that the proposed system was highly responsive and able to detect the types and concentrations of air pollutants instantly. Furthermore, equipped with the mobile internet, geo-tagged GPS location and web server on Raspberry Pi, the developed portable system could be accessed remotely.</span>

Trends of Transformation Characteristics of Ground-Level Ozone in Urban Peninsular Malaysia

Ozone (O3 ) is the second prominent air pollution in Malaysia. The annual variation of ozone concentration depends upon several conditions such as the sources of its precursor, the land use type and meteorological parameter. This study aims to understand the trends and issues of transformation characteristics of O3 in 4 urban area (Shah Alam, Kajang, Johor Bahru and Kota Bharu) during specific critical conversion time (CCT) as well as to introduce the critical transformation time (CTT) of O3 in 4 selected continuous air quality monitoring stations (CAQMS) from the year 2000 to 2011. The identification of CTT for O3 formation was identified occurring between 8.00 a.m and 11.00 a.m., and the O3 uni-modal peaks usually after CTT at approximately between 12.00 p.m and 4.00 p.m. The results indicated that the CTT of O3 in the Kota Bharu is slightly earlier occurring between 8.00 a.m to 10.00 a.m whereas Shah Alam, Kajang and Johor Bahru the CTT later occurring between 10.00 a.m to 11.00 a.m. Only Kota Bharu recorded data was below 100 part per billion volume (ppbv), while Shah Alam, Kajang and Johor have recorded exceedances above 100 ppbv. This research elucidates that CTT is adequate to control ozone concentration. Ozone might exceed Recommended Ambient Air Quality Guideline (RMAAQC) unless nitrogen emissions are adequately managed, due to the detrimental effects for those who are at risk of respiratory health problems resulting from air pollution.

Economic losses due to health hazards caused by haze event in Johor Bahru, Malaysia

This study assessed the health risk analysis of haze pollution in Pasir Gudang and Larkin. The relationship between health risk and economic effect due to air pollution exposure in Johor is still poorly understood. Therefore, the objective of this study was to analyse the relationship between air pollution and health. Then, the economic impact due to smoke haze on associated outpatients was calculated. Daily morbidity data from 2014 to 2016 for three haze-related illnesses were collected from two health clinics. Data on air quality were obtained at two Continuous Air Quality Monitoring (CAQM) stations in Johor. Health risks for all age categories in the haze periods were higher than those in non-haze periods. The outpatient morbidity cases in health clinics increased with the rising occurrence of smoke haze in Johor Bahru. The average annual economic losses due to the outpatient health impact of haze were valued at RM83,233 and RM107,486 for Pasir Gudang and Larkin, respectively.

Time effects of high particulate events on the critical conversion point of ground-level ozone

Particulate matter (PM), especially those with an aerodynamic particle size of less than 10 μm (PM10), is typically emitted from transboundary forest fires. A large-scale forest fire may contribute to a haze condition known as a high particulate event (HPE), which has affected Southeast Asia, particularly Peninsular Malaysia, for a long time. Such event can alter the photochemical reactions of secondary pollutants. This work investigates the influence of PM on ground-level ozone (O3) formation during HPE. Five continuous air quality monitoring stations from different site categories (i.e., industrial, urban and background) located across Peninsular Malaysia were selected in this study during the HPEs in 2013 and 2014. Result clearly indicated that O3 concentrations were significantly higher during HPE than during non-HPE in all the sites. The O3 diurnal variation in each site exhibited a similar pattern, whereas the magnitudes of variation during HPE and non-HPE differed. Light scattering and atmospheric attenuation were proven to be associated with HPE, which possibly affected O3 photochemical reactions during HPE. Critical conversion time was used as the main determining factor when comparing HPE and non-HPE conditions. A possible screening effect that resulted in the shifting of the critical transformation point caused a delay of approximately of 15–30 min. The shifting was possibly influenced by the attenuation of sunlight in the morning during HPE. A negative correlation between O3 and PM10 was observed during the HPE in Klang in 2013 and 2014, with −0.87. Essentially, HPE with a high PM concentration altered ground-level O3 formation.

Design and Implementation of Portable Outdoor Air Quality Measurement System using Arduino

Recently, there is increasing public awareness of the real time air quality due to air pollution can cause severe effects to human health and environments. The Air Pollutant Index (API) in Malaysia is measured by Department of Environment (DOE) using stationary and expensive monitoring station called Continuous Air Quality Monitoring stations (CAQMs) that are only placed in areas that have high population densities and high industrial activities. Moreover, Malaysia did not include particulate matter with the size of less than 2.5μm (PM2.5) in the API measurement system. In this paper, we present a cost effective and portable air quality measurement system using Arduino Uno microcontroller and four low cost sensors. This device allows people to measure API in any place they want. It is capable to measure the concentration of carbon monoxide (CO), ground level ozone (O3) and particulate matters (PM10 & PM2.5) in the air and convert the readings to API value. This system has been tested by comparing the API measured from this device to the current API measured by DOE at several locations. Based on the results from the experiment, this air quality measurement system is proved to be reliable and efficient.

Variation of Ambient air Quality Scenario in Chittagong City: A Case Study of Air Pollution

Chittagong, the commercial capital of Bangladesh, is experiencing crucial health impacts resulting from deficient air quality. The ambient air quality data for particulate matter as well as criteria of gaseous pollutants were assembled during December 2013 to December 2015 from the Continuous Air Quality Monitoring Station (CAMS) located at Agrabad, Chittagong. Analysis showed that during April- October, 24 hour average concentration of PM10 and PM2.5 were within the National Ambient Air Quality Standard (NAAQS) level but it increased about three times during the whole non-monsoon period (November-March).The highest values found of PM2.5 were 321.1µg/m³ in January, 2013 and 220.34µg/m³ in December 2015. Whether, the highest alarming concentration of PM10 was reported as 474µg/m³ in January 2007.The other gaseous pollutants such as SO₂, NO₂, O₂ and CO remain well within the permissible limit except dry non-monsoon period. The yearly average increase of Air Quality Index (AQI) value indicates the growth rate of air pollution in Chittagong city. The main responsible pollutant for air pollution is found PM_2.5.

Urban heat island (UHI) influence on secondary pollutant formation in a tropical humid environment

ABSTRACTThe combined action of urbanization (change in land use) and increase in vehicular emissions intensifies the urban heat island (UHI) effect in many cities in the developed countries. The urban warming (UHI) enhances heat-stress-related diseases and ozone (O3) levels due to a photochemical reaction. Even though UHI intensity depends on wind speed, wind direction, and solar flux, the thermodynamic properties of surface materials can accelerate the temperature profiles at the local scale. This mechanism modifies the atmospheric boundary layer (ABL) structure and mixing height in urban regions. These changes further deteriorate the local air quality. In this work, an attempt has been made to understand the interrelationship between air pollution and UHI intensity at selected urban areas located at tropical environment. The characteristics of ambient temperature profiles associated with land use changes in the different microenvironments of Chennai city were simulated using the Envi-Met model. The simulated surface 24-hr average air temperatures (11 m above the ground) for urban background and commercial and residential sites were found to be 30.81 ± 2.06, 31.51 ± 1.87, and 31.33 ± 2.1ºC, respectively. The diurnal variation of UHI intensity was determined by comparing the daytime average air temperatures to the diurnal air temperature for different wind velocity conditions. From the model simulations, we found that wind speed of 0.2 to 5 m/sec aggravates the UHI intensity. Further, the diurnal variation of mixing height was also estimated at the study locations. The estimated lowest mixing height at the residential area was found to be 60 m in the middle of night. During the same period, highest ozone (O3) concentrations were also recorded at the continuous ambient air quality monitoring station (CAAQMS) located at the residential area.Implications: An attempt has made to study the diurnal variation of secondary pollution levels in different study regions. This paper focuses mainly on the UHI intensity variations with respect to percentage of land use pattern change in Chennai city, India. The study simulated the area-based land use pattern with local mixing height variations. The relationship between UHI intensity and mixing height provides variations on local air quality.

Functionality of openair package in air pollution assessment and modeling — a case study of Krakow

AbstractThe paper presents the possibilities of selected functions from openair package for R programming environment in urban air pollution assessment. Examples of data analysis were based on the measurements from continuous air quality monitoring stations in Krakow (Poland). In order to present additional functionality of this software, modeling results of back trajectories and air pollution dispersion were used. Functions and visualization methods included in openair package make scrutiny of large data sets easier and less time consuming. They allow for analysis of measurement data with the determination of general relationships between parameters, additional complex spatial analyses for back trajectories, and validation of air pollution dispersion models. Openair package is, therefore, a valuable and functional tool that can be successfully used as a support in the air quality management system.

Status of Ambient Particulate Matter and Black Carbon Concentrations in Rajshahi Air, Bangladesh

Air borne particulate matter (PM) samples (both PM10 and PM2.5) were collected simultaneously from continuous air quality monitoring station (CAMS) at Rajshahi city from December 2012 to February 2013 using two Air Metrics MiniVol samplers. The samples were analyzed for mass and black carbon (BC) concentrations. The present results were compared with the data set during December 2001 to February 2002. It was found that the mean PM10, PM2.5 and BC concentrations have increased 3.3, 6.1 and 3.4 times, respectively than in December 2001 to February 2002 period. Similarly, the ratio of PM2.5/PM10 has increased twice than the previous cited time. In case of BC/PM2.5 ratio, value becomes more than half than the previous period. Hence, PM2.5 concentration has increased tremendously and due to the implementation of policies especially on motor vehicles, BC concentration does not increase linearly as PM2.5. The present data have showed that about 78% of PM10 is PM2.5 whereas in 2001-2002, PM2.5 was only 38% of PM10. The high PM2.5 at Rajshahi city might be due to both local effect and long-range transport.Journal of Bangladesh Academy of Sciences, Vol. 39, No. 2, 147-155, 2015

The statistical evaluation and comparison of ADMS-Urban model for the prediction of nitrogen dioxide with air quality monitoring network.

In many countries, road traffic is one of the main sources of air pollution associated with adverse effects on human health and environment. Nitrogen dioxide (NO2) is considered to be a measure of traffic-related air pollution, with concentrations tending to be higher near highways, along busy roads, and in the city centers, and the exceedances are mainly observed at measurement stations located close to traffic. In order to assess the air quality in the city and the air pollution impact on public health, air quality models are used. However, firstly, before the model can be used for these purposes, it is important to evaluate the accuracy of the dispersion modelling as one of the most widely used method. The monitoring and dispersion modelling are two components of air quality monitoring system (AQMS), in which statistical comparison was made in this research. The evaluation of the Atmospheric Dispersion Modelling System (ADMS-Urban) was made by comparing monthly modelled NO2 concentrations with the data of continuous air quality monitoring stations in Kaunas city. The statistical measures of model performance were calculated for annual and monthly concentrations of NO2 for each monitoring station site. The spatial analysis was made using geographic information systems (GIS). The calculation of statistical parameters indicated a good ADMS-Urban model performance for the prediction of NO2. The results of this study showed that the agreement of modelled values and observations was better for traffic monitoring stations compared to the background and residential stations.

Seasonal Variation in Surface Ozone Concentrations, Meteorology and Primary Pollutants in Coastal Mega City of Mumbai, India

In the present the study variation in ground level ozone (GLO) concentration with respect to availability of precursor pollutants and meteorological parameters in the tropical climatic conditions in Mumbai, India is discussed. The concentration of various pollutants and meteorological parameters have been monitored at the continuous air quality monitoring station of Maharashtra Pollution Control Board, located in Bandra (Mumbai) for two years. The analysis of the data indicates that the pattern of formation of GLO changes with change in season. The maximum concentration for GLO was experienced in the post monsoon season unlike any other study reported in the country. The study highlights that the post monsoon season experienced the highest number of hourly and eight hourly exceedances in the permissible limits prescribed by the Central Pollution Control Board. These high concentrations can be attributed to favorable climatic conditions and presence of precursor pollutants. This was proved by correlating GLO with precursor pollutants and meteorological parameters.

Trend of ambient air quality in Chittagong City

The ambient air quality data for particulate matter as well as criteria of gaseous pollutants were collected during December 2006 to December 2008 at the Continuous Air Quality Monitoring Station (CAMS) located at TV center, Pahartoli, Chittagong. It was observed that during April- October, 24 hour average concentration of PM10 and PM2.5 were within the National Ambient Air Quality Standard (NAAQS) level but it increased occasionally by more than two and a half times during the whole non-monsoon period (November-March). The highest values found of PM2.5 were 327 ?g/m3 and 254.9 ?g/m3 24 hour average concentration in January 2007 and December 2008 respectively. Whether, the highest alarming concentration of PM10 was reported as 545 ?g/m3 in January 2007. The other gaseous pollutants such as SO2, NO2, O3, CO and hydrocarbons remain well within the permissible limit except dry winter. DOI: http://dx.doi.org/10.3329/bjsir.v47i3.13062 Bangladesh J. Sci. Ind. Res. 47(3), 287-296 2012

An empirical analysis of the impact of a bus rapid transit system on the concentration of secondary pollutants in the roadside areas of the TransJakarta corridors

A bus rapid transit (BRT) system began operation in Jakarta City, Indonesia, in January 2004 and led to a modal shift from private to public modes of transport. This modal shift from car and motorcycle to BRT reduced the emission intensity of primary pollutants, such as NOx and CO. We applied a combined structural equation model and an artificial neural network to evaluate the impact of the BRT system on the concentration of secondary pollutants in the roadside areas in the BRT corridors. An empirical analysis was carried out using data collected at five continuous ambient air quality monitoring stations located near to the BRT TransJakarta corridors in 2005. The establishment of our structural equation model gives a better understanding of the cause–effect relationship among the factors influencing roadside ambient air pollution, and was useful in simplifying the complexity of our artificial neural network model for predicting the modal shift’s impact on the PM10 values and concentration of O3. The introduction of the BRT system, and the modal shift it produced, had a greater influence on rapidly decaying pollutants, such as PM10, than on O3 because of the exposure to near-source microenvironments, such as the roadside of the TransJakarta corridors.

Evaluation of non-methane hydrocarbon (NMHC) emissions based on an ambient air measurement in Tokyo area, Japan

Non-methane hydrocarbons (NMHCs) are known to have an important role on air quality due to their high reactivity. NMHC analysis has been performed on 148 ambient air samples collected at five different sites in the Kanto area (Tokyo metropolitan area and surrounding six prefectures) of Japan in summer and winter of 2008, and fifty NMHCs have been determined and quantified. A field measurement campaign has been conducted at one of the busiest intersections in Tokyo metropolitan area in winter of 2008. NMHC emissions are evaluated through comparison of distributions of individual NMHCs emitted from motor vehicles, which are estimated from the measurements, with those determined from the current emissions inventory. The comparison revealed that the measured distributions of acetylene, ethylene and toluene showed a good agreement with those estimated from the emissions inventory (the values estimated from the measurements are a factor of 1.5, 0.56 and 2.3 larger than the emissions inventory in median, respectively), however, propane and isobutane are found to be significantly underestimated in the emissions inventory (the measured values were a factor of 18 and 5.1 larger than the emissions inventory, respectively). The significant underestimate of propane can be explained by that the current emissions inventory does not consider emissions from liquefied propane gas (LPG) fueled vehicles. However, for isobutane, reasons for the underestimate are still unclear. Another field measurement has been conducted in summer of 2008, where the air samples have been collected at three different sites on the ground and by a helicopter as well. Remarkable high concentrations of 1-butene and cis- and trans-2-butenes have been sporadically observed in the samples collected at Urayasu in the coastal area of Tokyo bay. Calculated propylene equivalent (PE) concentrations of butenes revealed that those have a significantly important role in ozone formation when the air plume is affected by emissions from their emission sources. The PE concentrations of butenes varied from 0.1 to 39 ppbC, and accounted for 1.5–75% of total PE concentrations at Urayasu. Most of the continuous air quality monitoring stations does not record concentrations of individual hydrocarbons, therefore, the importance of reactive and low concentration hydrocarbon such as butenes might be overlooked in the current emissions inventory and/or air quality model. In this paper, the reliability of NMHC emissions is evaluated based on the field measurements. Their possible impacts on air quality in the Kanto area are discussed as well, based on the calculated propylene equivalent concentrations.

The influence of BRT on the ambient PM10 concentration at roadside sites of Trans Jakarta Corridors

Bus Rapid Transit (BRT) system was began operation in Jakarta City in January 2004 which triggers a switch of car and motorcycle riders to BRT users. These modal shift changes from car and motorcycle to BRT reduce the emission intensity of primary pollutants such as NOx, PM10 and CO. The objective of this study was to evaluate the BRT system's impact on ambient concentration of PM10 near the BRT's corridors. By using data collected at five continuous ambient air quality monitoring stations near the BRT corridor TransJakarta in 2005, we apply structural equation model which capable to analyze cause-effects relationship among factors in determining PM10 concentration near the BRT lines. Vehicle exhaust emission especially motorcycle and diesel vehicles emission and also micro-meteorology positively affects on PM10 concentration both for weekdays and weekend days. In contrast, wind speed and direction gave negative influence on PM10 concentration. Motorcycles emissions keep remain as the main contributor to vehicle emissions and the influence was larger in the weekend compare to weekday. It was big challenge to shift and reduce the usage of motorcycle by the park and ride motorcycle system as the access mode to BRT which will improve the PM10 concentration near the TransJakarta BRT's lines.

RELATIVE RISK OF RESPIRATORY AND CARDIOVASCULAR CASE ADMISSIONS TO HOSPITAL KUALA LUMPUR ASSOCIATED WITH INCREMENTS OF CRITERIA AIR POLLUTANTS

ISEE-437 Aim: The aim of the study is to determine the relationships between daily variations in five air pollutants, with variations in hospital admissions due to respiratory and cardiovascular morbidity. Methods: The study period was from 1 January 2000 to 31 December 2003. The study populations were patients admitted to Hospital Kuala Lumpur during the study period. The cases were those suffering from respiratory (J00-J46) and cardiovascular (I10-I99) diseases, based on the International Classification of Disease, Tenth Revision. Data on the daily mean concentrations of particulate matter <10 micron (PM10), sulphur dioxide, nitrogen dioxide, ozone and carbon monoxide were obtained from the Department of the Environment. The data were generated by the ASMA Sdn. Bhd. continuous air quality monitoring stations. The Malaysian Meteorological Services provided the daily temperature and rainfall data. Poisson regression model was then used to model the daily counts of respiratory and cardiovascular cases as the dependent variable; while time, temperature, rainfall and pollutant concentrations act as the independent variables. All models were estimated using the generalized additive model procedure in SAS. The relative risks (RR) for respiratory and cardiovascular case admissions associated with quartile increments in each pollutant were estimated using the models. Results: The RR for adult cardiovascular case admissions associated with quartile increments in PM10 were found to be significant. With quartile increments in nitrogen dioxide, significant RR for adult respiratory case admissions were observed. However, no association with cardiovascular admissions was seen. Quartile increments in sulphur dioxide were associated with significant immediate RR for adult cardiovascular case admissions, but with significant lagged RR for adult respiratory case admissions. Quartile increments in ozone and carbon monoxide were not associated with significant RR for either adult respiratory or cardiovascular case admissions. Conclusion: PM10 is sensitive for adults with cardiovascular diseases, while nitrogen dioxide is sensitive for adults with respiratory diseases. Sulphur dioxide is sensitive, to some extent, for adults with respiratory and cardiovascular diseases. Therefore, PM10 and nitrogen dioxide seem to be the pollutants of greatest concern in this study.

The use of MODIS data and aerosol products for air quality prediction

The Center for Space Research (CSR) is exploring new approaches to integrate data collected by the MODerate resolution Imaging Spectroradiometer (MODIS) sensor, flown on NASA's Earth Observing System (EOS) satellites, into a real-time prediction methodology to support operational air quality forecasts issued by the Monitoring Operations Division (MOD) of the Texas Commission on Environmental Quality (TCEQ). Air pollution is a widespread problem in the United States, with over 130 million individuals exposed to levels of air pollution that exceed one or more health-based standards. Texas air quality is under assault by a variety of anthropogenic sources associated with a rapidly growing population along with increases in emissions from the diesel engines that drive international trade between the US and Central America. The challenges of meeting air quality standards established by the Environmental Protection Agency are further impacted by the transport of pollution into Texas that originates from outside its borders and are cumulative with those generated by local sources. In an earlier study, CSR demonstrated the value of MODIS imagery and aerosol products for monitoring ozone-laden pollution that originated in the central US before migrating into Texas and causing TCEQ to issue a health alert for 150 counties. Now, data from this same event are re-analyzed in an attempt to predict air quality from MODIS aerosol optical thickness (AOT) observations. The results demonstrate a method to forecast air quality from remotely sensed satellite observations when the transient pollution can be isolated from local sources. These pollution sources can be separated using TCEQ's network of ground-based Continuous Air quality Monitoring (CAM) stations.

Trend of Particulate Matter PM 2.5 and PM 10 in Dhaka City

Dhaka City has been affecting with severe air pollution particularly by particulate matter. The ambient air quality data for particulate matter were collected during April 2002 to September 2005 at the Continuous Air Quality Monitoring Station (CAMS) located at Sangshad Bhaban, Dhaka. Data reveal that the pollution from particulate matter greatly varies with climatic condition. While the level comes down the limit value in the monsoon period (April-October), it goes beyond the limit during non-monsoon time (November-March). The latest data show that during monsoon period PM 10 concentration varies from 50 μg/m3 to 80 μg/m3 and PM 2.5 concentration from 20 μg/m3 to 60 μg/m3 and during non monsoon period PM 10 varies from 100 μg/m3 to 250 μg/m3 and PM 2.5 varies from 70 μg/m3 to 165 μg/m3. The seasonal variation clearly indicates the severe PM 10 pollution during the dry winter season and also sometime during post-monsoon season in Dhaka City. Keywords: Air pollution; PM 2.5; PM 10; Air quality DOI: http://dx.doi.org/10.3329/bjsir.v46i3.9049 BJSIR 2011; 46(3): 389-398