Wednesday, 12 October 2011

AIR POLLUTION

AIR POLLUTION


            [I] Air pollution is the introduction of chemicals, particular matter, or biological matters that cause harm or discomfort to humans or other living organisms, or cause damage to the natural environment or build environment, into the atmosphere.


            Blacksmith Institute’s report on the World’s Worst Polluted  Places, 2008, cited urban air and indoor air as the most dreadful problems of air pollution.


            The main material of air pollution that harms living organisms and its surroundings is called air pollutant. Air pollutants can be induced by man or natural, and they can either be gases, droplets of liquid or solid elements.


            Pollutions that are released directly through a manner of course are called primary air pollutants. Examples are carbon monoxide from motor vehicles, sulfur dioxides from industrial factories, and ashes spewed from erupting volcanoes.


            When primary air pollutants interact with each other, the reaction is called a secondary air pollutant.  An example is smog which is also called ground level ozone.


            Common pollutants generated by mankind are the following: sulfur oxides, nitrogen oxides, carbon monoxide, carbon dioxide, volatile organic compounds, particulate matter, persistent free radicals, toxic metals, chlorofluorocarbons, ammonia, odors, and radioactive pollutants.


            Anthropogenic sources are mostly due to burning various fuels. Those that come from factories and incinerators, furnaces and other heating devices that uses fuel to produce heat, and power plants are called stationary sources. Those that originate from motor vessels are called mobile sources.


            Other anthropogenic sources include forestry and agriculture practices as controlled burning, dust, chemicals, fumes from solvent, methane from landfills, and military equipments as germ warfare, rocketry, poisonous gases, and nuclear armaments.


            Air pollutants that come from natural sources are dust from geographies with almost no plant life, methane from animal digestion, radon gas form decays of radioactive matters from inside the Earth, wildfire carbon monoxide and smoke, plants that generates VOCs on hot days, and volcanic chlorine, ash, and sulfur.


            People try to put values on emission factors of air pollutants to determine the amount of volume a pollutant is releasing to the air. However, these are just  medians that are commonly taken as representatives.


            People often spend their time indoors. Yet, air pollution is concentrated in an indoor facility where there is inadequate ventilation or air circulation. Sometimes, radon gas which is carcinogenic is emitted from the Earth’s crust and becomes trapped inside buildings.


            Other sources of indoor air pollution are formaldehyde gas, plywood, carpeting, volatile organic compounds coming from paints and solvents that are in the process of drying, lead paints becoming dust, scented air fresheners, incense, fires in fireplaces and wood stoves, chemical sprays as pesticides that can even cause deaths.    


            According to the World Health Organization, approximately 2.4 million expire annually due to air pollution, with little more than half of the total number of deaths cause by indoor air pollution. Half a million Americans’ deaths are attributed to cardiopulmonary diseases caused by inhaling polluted fine particles.   A strong connection between carbon monoxide emitted by motor vehicles and pneumonia were shown by a study performed by the University of Birmingham. In fact, there are more air pollution connected deaths than deaths due to accidents.


            A study conducted in 2005 stated that in Europe, a little more than three hundred thousand people die yearly due to pollution connected diseases as emphysema, lung diseases, respiratory allergies, asthma, and  heart diseases.


            A proposal by US EPA recommended that altering, modifying or changing the diesel engine technology can drastically reduce respiratory-related mortalities.  Health effects  or symptoms created by air pollution are wheezing,  breathing, coughing, cardiac and respiratory conditions. These precipitates increased intake of medicines, medical visits, or even death. How a person reacts to pollutants is dependent on the degree and intensity of exposure, the person’s genetics and health status, and the type of pollutant inhaled.


            Among the efforts made to reduce air pollution are land use planning, regulations on mobile sources as lawn mowers, farm equipments, and ships, improved fuel efficiency as use of hybrid vehicles, utilization of cleaner fuels as biodiesel, bioethanol, or electric vehicles. 



 

[i] En.wikipedia.org



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