Chemical composition of the haze in Malaysia 2005

Norela, S.; Saidah, M. S.; Mahmud, Mastura

doi:10.1016/j.atmosenv.2013.05.024

Cited by 36 publications

(19 citation statements)

References 12 publications

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“…Most exceedance days occurred during the dry seasons of the SW monsoon and INT.2 (middle May until end of October) with 66 and 71 % exceedance respectively. Similar observations of high exceedances during the SW monsoon dry season have been recorded for Peninsular Malaysia in general and the Klang Valley in particular (Rashid and Griffiths, 1995;Juneng et al, 2011;Norela et al, 2013;Tahir et al, 2013b;Amil et al, 2014). Higher mass concentrations during the dry season were also seen in other SEA (Kim Oanh et al, 2006;Lestari and Mauliadi, 2009) and Asian cities (Reid et al, 2013).…”

Section: Source Apportionmentsupporting

confidence: 79%

“…The goal of receptor models is to solve the chemical mass balance between measured species concentrations and source profiles. One of the models used to solve the chemical mixture is positive matrix factorisation (PMF), first developed by Paatero and Tapper (1993). Subsequently, numerous other studies have employed this method in their PM 2.5 receptor modelling including many undertaken in the Asian region.…”

Section: Introductionmentioning

confidence: 99%

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Seasonal variability of PM<sub>2.5</sub> composition and sources in the Klang Valley urban-industrial environment

et al. 2016

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Abstract. This study investigates the fine particulate matter (PM2.5) variability in the Klang Valley urban-industrial environment. In total, 94 daily PM2.5 samples were collected during a 1-year campaign from August 2011 to July 2012. This is the first paper on PM2.5 mass, chemical composition and sources in the tropical environment of Southeast Asia, covering all four seasons (distinguished by the wind flow patterns) including haze events. The samples were analysed for various inorganic components and black carbon (BC). The chemical compositions were statistically analysed and the temporal aerosol pattern (seasonal) was characterised using descriptive analysis, correlation matrices, enrichment factor (EF), stoichiometric analysis and chemical mass closure (CMC). For source apportionment purposes, a combination of positive matrix factorisation (PMF) and multi-linear regression (MLR) was employed. Further, meteorological–gaseous parameters were incorporated into each analysis for improved assessment. In addition, secondary data of total suspended particulate (TSP) and coarse particulate matter (PM10) sampled at the same location and time with this study (collected by Malaysian Meteorological Department) were used for PM ratio assessment. The results showed that PM2.5 mass averaged at 28 ± 18 µg m−3, 2.8-fold higher than the World Health Organisation (WHO) annual guideline. On a daily basis, the PM2.5 mass ranged between 6 and 118 µg m−3 with the daily WHO guideline exceeded 43 % of the time. The north-east (NE) monsoon was the only season with less than 50 % sample exceedance of the daily WHO guideline. On an annual scale, PM2.5 mass correlated positively with temperature (T) and wind speed (WS) but negatively with relative humidity (RH). With the exception of NOx, the gases analysed (CO, NO2, NO and SO2) were found to significantly influence the PM2.5 mass. Seasonal variability unexpectedly showed that rainfall, WS and wind direction (WD) did not significantly correlate with PM2.5 mass. Further analysis on the PM2.5 ∕ PM10, PM2.5 ∕ TSP and PM10 ∕ TSP ratios reveal that meteorological parameters only greatly influenced the coarse particles (particles with an aerodynamic diameter of greater than 2.5 µm) and less so the fine particles at the site. Chemical composition showed that both primary and secondary pollutants of PM2.5 are equally important, albeit with seasonal variability. The CMC components identified were in the decreasing order of (mass contribution) BC > secondary inorganic aerosols (SIA) > dust > trace elements > sea salt > K+. The EF analysis distinguished two groups of trace elements: those with anthropogenic sources (Pb, Se, Zn, Cd, As, Bi, Ba, Cu, Rb, V and Ni) and those with a crustal source (Sr, Mn, Co and Li). The five identified factors resulting from PMF 5.0 were (1) combustion of engine oil, (2) mineral dust, (3) mixed SIA and biomass burning, (4) mixed traffic and industrial and (5) sea salt. Each of these sources had an annual mean contribution of 17, 14, 42, 10 and 17 % respectively. The dominance of each identified source largely varied with changing season and a few factors were in agreement with the CMC, EF and stoichiometric analysis, accordingly. In relation to meteorological–gaseous parameters, PM2.5 sources were influenced by different parameters during different seasons. In addition, two air pollution episodes (HAZE) revealed the influence of local and/or regional sources. Overall, our study clearly suggests that the chemical constituents and sources of PM2.5 were greatly influenced and characterised by meteorological and gaseous parameters which vary greatly with season.

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Section: Source Apportionmentsupporting

confidence: 79%

Section: Introductionmentioning

confidence: 99%

Seasonal variability of PM<sub>2.5</sub> composition and sources in the Klang Valley urban-industrial environment

et al. 2016

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“…Since the Recommended Malaysian Ambient Air Quality Standards (RMAAQS) of PM have been established for particulate matter with diameters ≤ 10 µm (PM 10 ), total suspended particles, and lead (Pb), many reports have presented data regarding these forms of PM (Abas and Simoneit, 1996;Fang et al, 1999;Okuda et al, 2002;Abas et al, 2004a, b;Omar et al, 2007;Norela et al, 2013;Wahid et al, 2013;Jamhari et al, 2014). Particulate matter with diameters ≤ 2.5 µm (PM 2.5 ) has a higher health risk than PM 10 due to its ability to penetrate deep into the respiratory tract, longer transport distance and longer residence time in the atmosphere.…”

Section: Introductionmentioning

confidence: 99%

A Case Study of PM2.5 Characterization in Bangi, Selangor, Malaysia during the Southwest Monsoon Season

Fujii

Mahmud

Tohno

et al. 2016

Aerosol Air Qual. Res.

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A case study was carried out to characterize the ambient PM 2.5 based on ground-based sampling in Bangi, Selangor, Malaysia in September, 2013 during the southwest monsoon season. We determined the total mass concentration, organic carbon, elemental carbon (EC), and metals in PM 2.5 samples. The mean PM 2.5 mass concentration was 44.5 µg m -3 , showing that it exceeded the national air quality standard of 35 µg m -3 for 24-hour PM 2.5 by the U.S. Environmental Protection Agency. Relatively high OC and EC concentrations of this study compared to those of other Southeast Asian countries were observed, which indicate that significant sources of OC and EC exist. The results of char-EC/soot-EC ratios strongly suggest that biomass burning is the main contributor to ambient EC concentrations compared to coal combustion and motor vehicle emissions. From calculations using the mass closure model, organic matter was the most abundant component in PM 2.5 mass at 22.4 ± 6.65 µg m -3 , followed by nss-sulfate at 4.84 ± 2.49 µg m -3 , and EC at 4.11 ± 0.916 µg m -3 . This result indicates that targeting the sources of carbonaceous PM 2.5 is a crucial step to improve the air quality in this study field.

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“…In Port Dickson, HPE occurred 30 times in 2013, and the highest impact was on June in which 26 locations were affected. HPE in Malaysia mainly occurs due to the relatively higher anthropogenic sources, such as biomass burning and agricultural land clearing (Norela et al 2013). The high occurrence of HPE is also influenced by meteorological parameters, such as temperature, relative humidity, rainfall and wind direction (Amil et al 2016;Khan et al 2016).…”

Section: Resultsmentioning

confidence: 99%

Transformational characteristics of ground-level ozone during high particulate events in urban area of Malaysia

Awang

Ramli

Shith

et al. 2018

Air Qual Atmos Health

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Observations of ground-level ozone (O 3), nitric oxide (NO), nitrogen dioxide (NO 2), particulate matter (PM 10) and meteorological parameter (temperature, relative humidity and wind speed) fluctuations during high particulate event (HPE) and non-HPE in Malaysia have been conducted for 2 years (2013 and 2014). The study focuses on urban areas, namely, Shah Alam, Petaling Jaya and Bandaraya Melaka. The diurnal variations of ground-level O 3 concentration were higher during HPE than those during non-HPE in all urban areas. The concentration of O 3 fluctuated more in 2014 than 2013 due to the higher incidences of HPE. Temperature and wind speed fluctuated with higher PM 10 , NO 2 and NO concentrations during HPE than those during non-HPE in all urban sites. Relative humidity was lower during HPE than that during non-HPE. Positive correlations were found between PM 10 and ozone during HPE for Shah Alam and Petaling Jaya with 0.81 and 0.79, respectively. Meanwhile, negative correlation (− 0.76) was recorded for Bandaraya Melaka. The non-HPE correlation of PM 10 and O 3 showed negative values for all locations except Petaling Jaya (0.02). Temperature and wind speed shows a strong positive correlation with ozone for all locations during HPE and non-HPE with the highest at Shah Alam (0.97). Inverse relationships were found between relative humidity and O 3 , in which the highest was for Shah Alam (− 0.96) in 2013 and Shah Alam (− 0.97) and Bandaraya Melaka (− 0.97) in 2014. The result of the ozone best-fit equation obtained an R 2 of 0.6730. The study parameters had a significant positive relationship with the ozone predictions during HPE.

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Chemical composition of the haze in Malaysia 2005

Cited by 36 publications

References 12 publications

Seasonal variability of PM<sub>2.5</sub> composition and sources in the Klang Valley urban-industrial environment

Seasonal variability of PM<sub>2.5</sub> composition and sources in the Klang Valley urban-industrial environment

A Case Study of PM2.5 Characterization in Bangi, Selangor, Malaysia during the Southwest Monsoon Season

Transformational characteristics of ground-level ozone during high particulate events in urban area of Malaysia

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Chemical composition of the haze in Malaysia 2005

Cited by 36 publications

References 12 publications

Seasonal variability of PM&lt;sub&gt;2.5&lt;/sub&gt; composition and sources in the Klang Valley urban-industrial environment

Seasonal variability of PM&lt;sub&gt;2.5&lt;/sub&gt; composition and sources in the Klang Valley urban-industrial environment

A Case Study of PM2.5 Characterization in Bangi, Selangor, Malaysia during the Southwest Monsoon Season

Transformational characteristics of ground-level ozone during high particulate events in urban area of Malaysia

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Seasonal variability of PM<sub>2.5</sub> composition and sources in the Klang Valley urban-industrial environment

Seasonal variability of PM<sub>2.5</sub> composition and sources in the Klang Valley urban-industrial environment