Air pollution has been one of the major health risks in the Philippines. Air pollutants are confirmed to be a major cause of premature death and illnesses, and are the primary reason for a wide range of respiratory and heart ailments according to the Clean Air Initiative for Asian Countries.[1] Thus, the government was prodded to pass Republic Act No. 8749 known as the “Philippine Clean Air Act of 1999” to minimize air pollution and create a more desirable living environment. Since then, designated branches of the government have constantly monitored air composition and the study of air particulate matter has become an active research area in the Philippines. One of these studies is “Air Pollutant Characterization and Source Identification of a Selected Metro Manila Sampling Site” (2004) by Dr. Leni L. Quirit of the Institute of Chemistry, University of the Philippines, Diliman.
In Quirit’s study, fine and coarse ambient Metro Manila aerosol samples were collected from January to May 2004, from an industrial and commercial site in Valenzuela, Bulacan and a relatively less polluted site, the National Mapping and Resources Information Agency (NAMRIA) inside a government office compound in Fort Bonifacio, Makati City. Calculations of sources of air particulates were determined using the stoichiometric elemental to formula ratios of common air pollutant sources, and Chemical Mass Balance—the simplest receptor modeling technique that estimates particulate source contributions at a receptor by comparing the chemistry of the ambient aerosol (colloidal-sized atmospheric particle) to the chemistry of the emissions from the various sources.[2] “From June to December 2004, relatively higher PM10 concentrations were measured in monitoring stations within Metro Manila compared to those outside Metro Manila…” according to the National Air Quality Status Report for 2004.[3] PM10, according to Dr. Quirit, is composed of two aerosol fractions: the fine fraction, known as PM2.5 (particles with aerodynamic equivalent diameter less than 2.5 μm), and the coarse fraction, known as PM2.5-10 (coarse particles with aerodynamic equivalent diameter between 2.5 to 10 μm).
Air sampling was done using 47 mm Nuclepore filters with Gent dichotomous sampler for a 12-hour sampling over a 24-hour period. A KEVEX 77 secondary target x-ray fluorescence spectrometer and an Eel Smoke Stain Reflectometer (43D Model) were used for elemental characterization and elemental carbon determination, respectively. The major aerosol components found in fine and coarse fractions in the NAMRIA and Valenzuela samples were: black carbon (also known as elemental carbon) which result from incomplete combustion of biomass or fossil fuels; wind-blown soil; ammonium sulfate (from fossil fuel sulfur, which is oxidized and subsequently reacts with ammonia in air); sea salt from sea spray; and trace elements from vehicular and industrial sources.
Findings showed no significant difference between the two sites in terms of calculated percentages of major aerosol components. However, in terms of actual concentrations, the Valenzuela site has a greater range of and higher levels of vehicle and industry derived air pollutants compared to the NAMRIA site. The study of the chemical composition of air particulates demonstrates the contribution of industrial and commercial sites to air pollution in Valenzuela.
Industrialization and commercialization have evidently brought harm to our environment. The continuous production of pollutants through vehicles, factories and other human activities has led to the accumulation of aerosol components resulting in air pollution. Many awareness programs and clean air projects such as the apprehension of smoke-belchers on the road have been initiated since the passage of the Philippine Clean Air Act of 1999. Studies like Dr. Leni Quirit’s work could help find solutions to air pollution and make us breathe clean air once again in Manila and the Philippines.
Dr. Leni Quirit is currently an Associate Professor in the Institute of Chemistry, University of the Philippines, Diliman. Her research work includes characterizing a rice endosperm protein; chemical equilibrium modeling of mines tailings pollution of seawater; sampling, analysis and modeling techniques for particulate elemental, gaseous inorganic and biotic pollutants in indoor and ambient air; and silica gel and zeolites from rice hull. Her recent project involves investigation lichens as a potential biomonitor for atmospheric pollution. For more information on the study featured in this article, you may contact Dr. Leni Quirit at (+632)9205427 (Telefax) or through email at lquirit (at) chem.upd.edu.ph.
By MMRParreño
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[1] Clean Air Initiative for Asian Countries, Clean Air Tool Kit for Local Governments <http://www.cleanairnet.org/caiasia/1412/articles-70096_introduction.pdf>
[2] Hanrahan, P.L.; Core, J.E., Automated chemical mass balance receptor modeling, 1986 <http://www.osti.gov/energycitations/product.biblio.jsp?osti_id=6861931>
[3] Environmental Management Bureau, Department of Environment and Natural Resources, National Air Quality Status Report for 2004 <http://www.emb.gov.ph/eeid/publicationfiles/statreport04content.pdf>
Note: Picture attached is by Kjellstrom, T. E., Neller A., Simpson R.W., Air pollution and its health impacts: the changing panorama, The Medical Journal of Australia, MJA 2002 177 (11/12): 604-608
