EESA Notes Lecture 2
Nitrogen Oxides and Sulfur Oxides
contributes a great amount in formation of ground ozones combined with volatile organic
compounds and the help of the heat and sunlight
form in any type of combustion process
When in air, can easily form acids (acids aerosols), therefore, nitrogen contributes in formation
of acid rain acidifies soils and open water
Can form nitrate particles when reacting with solid particles (salts) and can stay in the air or
come back to the soil surface through rain and contaminate soil.
Regardless of source of nitrogen oxides, nitrogen oxides can travel very far like ozone.
A major affect they have on our bodies is harm to our lungs and other breathing organs. The
intensity and location of damage to our body depends on the forms of the nitrogen oxides.
o If it is water soluble, it causes damage to upper areas of our respiratory system (e.g.
nose, bronchioles, throat)
o If it is not water soluble, it will reach lower areas of our lungs and affect small airways.
Nitrogen oxide gases are harmful to those who already have respiratory problems (e.g. Asthma
– most common) or weak immune system. Children are more vulnerable to such a negative
How are Sulfuric Oxides produced: usually during the burning of coal (soft coal) and oil and as
well from the extract of metals from ores.
Sulfur Dioxides are very soluble and can dissolve in water vapour or water molecules in air and
forms acid rain (similar to nitrogen dioxide).
Sulfur oxide gases can react with other solids and form solid sulfates.
Major reason lead is found in air (especially in urban areas) is b/c gasoline was leaded (not
Young children are particularly sensitive to the aversive effects of lead.
Lead in air can slowly deposit on soil and water surfaces (can enter our food chain).
Some may accidentally ingest lead contaminated soil
INDOOR AIR POLLUTION
Recently science realized that indoor air pollution can contain 2-5 times higher concentrations of
hazardous pollutants than outdoor air. Why? One reason is because modern buildings are built
very air tight to conserve energy but resulted in very little ventilation and contaminated air stays
in the buildings and accumulates. As well, most people spend about 90% of our time indoors
(e.g. children, elderly, pregnant women and those with chronic illness).
Sources of pollutants:
o building materials and furnishing (e.g. wall, paints)
o asbestos insulation (not in use as much)
o wet or damp carpet (e.g. chemicals on new carpets)
o furniture made of certain pressed wood products (e.g. almost all wood is treated and
pressed with glue which can evaporate)
o cleaning products and air fresheners (e.g. Lysol)
o personal care and hobbies (e.g. hairspray)
o Other sources can be from cooking and insecticides.