Atmospheric Pollution and Air Composition

Atmospheric Air

• Air is essential for human survival, with an average daily need of 14 kg, compared to 2 kg of water and 1 kg of food.
• Air is a mixture of 13 different gases, primarily consisting of Nitrogen (78%), Oxygen (21%), Argon and other gases (0.9%), and Carbon Dioxide (0.03%).

Air Pollutants

• The major atmospheric pollutants include Carbon monoxide (CO), Hydrocarbons (HC), Oxides of nitrogen (NOx), Oxides of sulphur (SOx), and Particulates (solids and liquids).
• Other pollutants include Carbon Dioxide (CO2), Chlorofluorocarbons (CFCs), and more.

Sources of Pollution

• Point Sources: include chimneys, processing minerals, drilling, crushing, screening, conveyors, and transhipment points.
• Non-point Sources: include blasting, haulage roads, and other extensive sources that cannot be readily identified.

Industrial Pollutants

• Gaseous pollutants: include Carbon Dioxide (CO2), Carbon Monoxide (CO), Sulphur Dioxide (SO2), Nitrogen Oxides (NOx), and Ozone (O3).
• Particulates: include smoke, soot, and other suspended particles.

Carbon Dioxide (CO2)

• Not typically considered a pollutant, but causes the "Greenhouse effect" when present in large quantities.
• Estimated to have increased by 26% between 1860 and 1986, and expected to double by 2040.

Carbon Monoxide (CO)

• Colourless, odourless, and tasteless gas with adverse health effects, including impaired oxygen delivery to organs and tissues.
• Most detrimental to people with cardiovascular diseases.

Sulphur Dioxide (SO2)

• Highly destructive pollutant with adverse effects on human health, including respiratory illnesses, cardiovascular diseases, and death.
• Damages plants at concentrations above 0.3-0.5 ppm, particularly coniferous plants.

Nitrogen Oxides (NOx)

• Nitrogen oxide (NO) is a reactive gas that contributes to tropospheric ozone formation.
• Nitrogen Dioxide (NO2) irritates lungs, causes bronchitis and pneumonia, and lowers resistance to respiratory infections.

Ozone (O3)

• A colourless gas that affects healthy adults and children, as well as people with impaired respiratory systems.
• Reduces lung function, causes coughing, sneezing, chest pain, and pulmonary congestion.

Chlorofluorocarbons (CFCs)

• Discovered in 1930, initially considered inert, but now known to react with Ozone (O3) and cause ozone layer depletion.
• Depletion of the ozone layer allows hazardous ultraviolet radiations into the troposphere, causing skin cancers.

Greenhouse Gases

• Gases like CO2, CH4, NxOx, CFCs, and O3, which contribute to the "Greenhouse effect" and global warming when present in large quantities.