Over the past centuries, people have engaged in many activities that brought about changes in the quality of air in Metropolitan Manila, the greater metropolitan area of the city of Manila, the National capital of the Philippines. These changes were introduced with the construction of cities and during the onset of the industrial Revolution. Urban construction, transportation and industrial activities up to the present times have added new materials not normally found in air.
Some of these changes are beneficial while others are harmful. These materials have changed the quality of the air. The air that surrounds us contains substances which could be considered examples of natural pollutants such as ashes from volcanic eruptions, salt from the sea, and even pollen grains from plants. These air pollutants if present in air in large amounts can cause harm to life and property.
Human activities have added more pollutants to the air. These air pollutants are of two groups: Those that affect our health such as Particulate Matter or Suspended Particulates, sulfur oxide, nitrogen oxide, Air Toxics, Carbon Monoxide and Hydrocarbons. The other group of air pollutants are those that affect our environment, which cause harm by altering the properties of the air such as Ozone and Photochemical Smog and Depleters of Stratospheric Ozone.
Transportation and industry have contributed much to the pollution of the air. Motor vehicles are the major sources and contributor of pollutants in cities like Metro Manila. Gasoline-fueled vehicles produce more particulates and oxides of nitrogen. Human activities have also upset the balance in ozone layer.
Knowing the harmful effects of air pollution, what then should people do about it? The most we can do is to reduce the amount of harmful substances that will enter the atmosphere and remove as much pollutants from the air as possible.
Removing pollutants from the air is not as effective as preventing pollution and reducing pollution. Preventing pollution is more effective and easier to do than removing pollutants from the air. Nature often does this for us for examples the high rainfall and the frequent and strong typhoons cleanse the air for us. However, we have no control over Nature’s self-cleansing schedule.
Santos, Gil Nonato C and Jorge P. Ocampo (2003). Science and Technology I. Rex Printing Company, Inc. Manila.