Experimental Study of Biodegradation of Ethanol and Toluene Vapors

CHAPTER ONE – INTRODUCTION
1.1 Air Pollution in North America
All unwanted chemicals or other materials found in the air which can harm
health, property and the environment are called air pollutants. Public concern about air
pollution is rapidly growing. Authorities in many countries have adopted stringent
regulations that limit emissions to protect public health and the environment. The
emissions of various air pollutants that affect our health and contribute to air pollution
problems such as smog (smoke + fog) are tracked by Environment Canada. Most of our
industrial and agricultural processes, transport operations and energy production
systems generate gaseous emissions often of a polluting nature.
The thick, yellowish haze that can hang over our skylines is smog, and it is
affecting our health. Smog can irritate the eyes, nose and throat. As levels increase,
smog can cause more serious health problems such as asthma attacks, coughing, chest
pain and decreased lung function. Crops, trees and other vegetation are also affected.
The main ingredient in smog is ground-level ozone, formed when nitrogen oxides
(NO x ) and volatile organic compounds (VOCs) react in stagnant sunlight (Environment
Canada, 2005a).
VOCs are an aggregate grouping of almost 1000 organic substances that readily
volatilize. VOC substances of interest to the Environment Canada’s National Pollutant
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