Environmental health addresses all the physical, chemical, and biological factors external to a person, and all the related factors impacting behaviours. It encompasses the assessment and control of those environmental factors that can potentially affect health. Although many air pollutants are invisible, they can seriously impact our health, the environment, and our quality of life. Air pollutants may cause respiratory diseases, cancer and other health effects. Pollutants also may create odours and smog, diminishes the protective ozone layer, and contributes to other environmental problems, such as acid rain and global climate change. The air inside homes, schools, and other buildings also may contain pollutants that enter from outdoors and those generated indoors. Mold, radon, tobacco smoke, carbon monoxide, and chemical emissions from products and furnishings are some of the important pollutants that may be present in our homes and other indoor environments.(Frumkin:2010)

Particulate matter (PM) affects more people than any other pollutant. The major components of PM are sulphate, nitrates, ammonia, sodium chloride, carbon, mineral dust and water. It consists of a complex mixture of solid and liquid particles of organic and inorganic substances suspended in the air. The particles are identified according to their aerodynamic diameter, as either PM10 (particles with an aerodynamic diameter smaller than 10 µm) or PM2.5 (aerodynamic diameter smaller than 2.5 µm). The latter are more dangerous since, when inhaled, they may reach the peripheral regions of the bronchioles, and interfere with gas exchange inside the lungs. The effects of PM on health occur at levels of exposure currently being experienced by most urban and rural populations in both developed and developing countries. Chronic exposure to particles contributes to the risk of developing cardiovascular and respiratory diseases, as well as of lung cancer. In developing countries, exposure to pollutants from indoor combustion of solid fuels on open fires or traditional stoves increases the risk of acute lower respiratory infections and associated mortality among young children; indoor air pollution from solid fuel use is also a major risk factor for chronic obstructive pulmonary disease and lung cancer among adults. The mortality in cities with high levels of pollution exceeds that observed in relatively cleaner cities by 15–20%. Even in the EU, average life expectancy is 8.6 months lower due to exposure to PM2.5 produced by human activities. (Barker & Tingey: 1992)
Sulphur dioxide (SO2) is a colourless gas with a sharp odour. It is produced from the burning of fossil fuels (coal and oil) and the smelting of mineral ores that contain sulphur. The main anthropogenic source of SO2 is the burning of sulphur-containing fossil fuels for domestic heating, power generation and motor vehicles. Sulphur dioxide SO2 can affect the respiratory system and the functions of the lungs, and causes irritation of the eyes. Inflammation of the respiratory tract causes coughing, mucus secretion, aggravation of asthma and chronic bronchitis and makes people more prone to infections of the respiratory tract. Hospital admissions for cardiac disease and mortality increase on days with higher SO2 levels. (Watson, et al: 2001)
When sulphur dioxide combines with water, it forms sulphuric acid; this is the main component of acid rain which is a cause of deforestation, skin infections, degradation of infrastructure and contamination of water sources thus affecting elements high up the cycle and food chain including both flora and fauna. Sulphuric acid combines with the water droplets that make up clouds, the water droplets become acidic. When those droplets fall to the ground as rain or snow, the acidity of the water can have damaging effects on the environment. When acid rain falls over an area, it can kill trees and harm animals, fish, and other wildlife. Acid rain destroys the leaves of plants. When acid rain infiltrates into soils, it changes the chemistry of the soil making it unfit for many living things that rely on soil as a habitat or for nutrition. Acid rain also changes the chemistry of the lakes and streams that the rainwater flows into, harming fish and other aquatic life which many are dependent on. (Watson, et al: 2001) The thinning ozone layer harms living things by air pollutants such as chlorofluorocarbons (or CFCs) destroy ozone molecules in the stratosphere. This has left places in the layer where the ozone is thin. These areas of thin ozone are called ozone holes. The ozone layer, located in the stratosphere layer of Earth’s atmosphere, shields our planet from the Sun’s ultraviolet radiation. Ultraviolet radiation causes skin cancer and damages plants and wildlife thus depleting the environmental health of the environment both flora and fauna. In recent decades the number of CFCs released into the atmosphere has decreased significantly due to an agreement between the nations of the world called the Montreal Protocol. Although it takes a long time to see the impact, the ozone holes might someday be smaller.( Fatta :2003)Accumulation of tropospheric ozone through air pollution harms living things. Ozone molecules in the troposphere damage lung tissues of animals and prevent plant respiration by blocking the openings in leaves, called stomata, where respiration occurs. Without sufficient respiration, a plant is not able to photosynthesize at a high rate and will not be able to grow leading to deforestation. Ozone is also able to enter the stomata and decay plant cells directly.(Frumkin:2010)
Our planet is currently warming much more rapidly than expected because of additional greenhouse gasses that are released into the atmosphere from air pollution. When fuels are burned, some of the pollutants released, such as carbon dioxide, are greenhouses gasses and the above stated chlorofluorocarbons. Through the process of photosynthesis, plants convert carbon dioxide into oxygen and use the carbon to grow larger thus keeping equilibrium and maintaining sustainable environmental health. However, the amount of carbon dioxide released by burning fuels is far greater than plants can convert. Cutting down forests exacerbates the problem. Global warming is changing climate globally and is causing significant changes to various regions of the world. For example polar ice melt and permafrost melt are causing changes in the habitat and resources for plants and animals living in polar ecosystems, ocean warming, rising sea levels, increasing runoff, and coral diseases are causing change in shallow marine ecosystems such as coral reefs and less rainfall in the dry interiors of continents due to global warming is limiting water resources for plants and animals. ( Coggle, et al: 1983)Air pollution does not only damage the air; it also damages environments on Earth’s surface and their inhabitants. Plants and animals are harmed by air pollution. Sometimes it is the pollutants themselves or indirectly causes damage. Other times pollutants combine and change the resources that plants and animals depend upon such as water, soil, and nutrients. Air is a major element in the florae and fauna eco systems thus sustainable development plans are required in order to keep the environmental health under check. |

REFERENCE
Howard Frumkin .(2010) “Environmental Health: from Global to Local. 2nd. Edition”. San Francisco, John Wiley & Sons
Watson, R. T.; and the Core Writing Team, ed. (2001),”Climate Change 2001: Synthesis Report, Contribution of Working Groups I, II, and III to the Third Assessment Report of the Intergovernmental Panel on Climate Change”, London, Cambridge University Press
Acheson, D (1998), “Independent Inquiry into Inequalities in Health”, London, Stationery Office
KC, Fatta B. (2003) “Principle of Management”. Kathmandu: Sukunda Pustak Bhawan.

“Emissions of hazardous air pollutants from lumber drying”. Forest Products Journal; July 1, 2008
Barker, J.R. and D.T. Tingey. (1992) “Air pollution effects on biodiversity”. Van No strand Reinhold, New York, New York.
Coggle, J.E., Lindop, Patricia J. (1983) "Medical Consequences of Radiation Following a Global Nuclear War." London ,Oxford Collage Press.

NAME: EDZAI M MAROWA

COURSE: ENVIRONMENTAL POLLUTION AND CONTROL

LECTURER: MR. MANYANHAIRE

REG No.: R107257HU

EXPLAIN USING SPECIFIC EXAMPLES THE ENVIRONMENTAL HEALTH EFFECTS OF AIR POLLUTION