7.1.1.2. PRIMARY POLLUTANTS

1. Carbon Monoxide: It is a colorless, odorless, poisonous gas that is produced by the incomplete burning of carbon based fuels (coal, petrol, diesel and wood) which comes from the automobile industries, exhaust devices, About 70% of CO emissions are from the transport sector. When the air is polluted with CO, human blood is likely to be deprived of oxygen and leads to coma and death. In mild dosages, it leads to headache.

Carbon monoxide (CO) is a harmful gas that is created when carbon-based fuels do not burn completely. Common sources of CO include car exhausts and industrial emissions, with transportation being the major contributor at about 70% of total emissions. The gas is dangerous because it is colorless and odorless, making it hard to detect. When CO enters the human body, it binds to hemoglobin in the blood more readily than oxygen does, preventing oxygen from reaching vital organs. This can lead to severe health issues, including headaches at low levels and possibly coma or death at high levels.

Imagine you’re sitting in a closed garage with a running car. The car emits carbon monoxide without you noticing. Over time, because the garage has no fresh air, the CO levels rise and you start feeling dizzy, similar to how high CO exposure can initially cause mild symptoms like headaches before leading to serious harm.

2. Oxides of Sulphur: SO2 is a gas produced from burning of coal, mainly in thermal power plants. Some industries such as paper mills produce SO2. It is injurious not only to men and plants, but it also attacks rapidly a few rocks such as limestone, marbles, electric contacts etc. It can even dissolve nylon. Paper absorbs SO2 causing the paper to become brittle and fragile. SO2 polluted air leads to corrosion of metals such as Fe, Zn, Cu, steel etc... SO2 is a major contributor to Smog and acid rain. Sulphur trioxide is more irritant than SO2 because it combines immediately with water to form sulphuric acid.

Sulfur dioxide (SO2) is a significant air pollutant that results from burning coal and other sulfur-containing fossil fuels, mainly in power plants and certain industries like paper manufacturing. When released into the atmosphere, SO2 poses health risks to humans and plants. It can corrode materials like metals and dissolve certain types of rocks, leading to structural damage. Moreover, SO2 can contribute to environmental issues like smog formation and acid rain, which have detrimental effects on ecosystems and infrastructure. Sulfur trioxide (SO3) is a more potent irritant that reacts with water to form sulfuric acid, further worsening air quality.

Think of taking a shower with hot water that produces steam. If you stay in the bathroom without ventilation, the air can become uncomfortable, much like how sulfur dioxide builds up in the air, hurting health. Just as moisture can damage walls and promote mold, SO2 can erode buildings and harm aquatic life due to acid rain.

3. Oxides of Nitrogen: Combustion of coal, oil, natural gas and gasoline which produces upto 50 ppm of Nitrogen. NOx are also produced when fossil fuels are burned especially in power plants and motor vehicles. NO poisoning results SILOFILTER disease. High levels of NO exposure causes cough and makes human beings feel short of breath. People who are exposed to NO for a long time have a higher chance of getting respiratory infections. NOx compounds contribute to the formation of Ozone. Similarly, when nitrogen oxide combines with SOx to form acid rain.

Nitrogen oxides (NOx), which include both nitric oxide (NO) and nitrogen dioxide (NO2), are produced extensively through combustion processes, including those in vehicles and power plants. Exposure to high levels of nitrogen oxides can cause respiratory issues like coughing and difficulty breathing, and long-term exposure raises the risk of respiratory infections. Additionally, nitrogen oxides play a role in forming ground-level ozone, a secondary pollutant that contributes to smog. When NOx combines with sulfur oxides (SOx), it can also result in acid rain, which can harm ecosystems and infrastructure.

It's similar to how smoke can accumulate in a small, enclosed space, making it difficult to breathe. Just as smoke can make you cough or feel unwell, nitrogen oxides can irritate the lungs and exacerbate existing health problems. If left unchecked, just like smoke can cause lasting damage to your health, high NOx levels can severely affect air quality.

4. Chloro Fluoro Carbons: CFCs (also known as Freon) are non-toxic. They contain Carbon, Fluorine and Chlorine atoms. The five main CFCs are the following: CFC – 11 (Trichloro Fluoro Methane CFCl3) CFC – 12 (Dichloro Fluoro Methane CFCl2) The major uses of CFCs are as coolants in refrigerators and in air conditioners; as solvents in cleaners particularly for electronic circuit boards etc. CFCs are the main cause of ozone depletion. CFCs have a lifetime in the atmosphere of about 20 to 100 years, and as a result, one free chlorine atom from a CFC molecule can do a lot of damage.

Chloro Fluoro Carbons (CFCs) are synthetic compounds that consist of chlorine, fluorine, and carbon. They have been widely used in refrigeration, air conditioning, and as solvents. Despite being non-toxic to humans, CFCs are known to deplete the ozone layer—a protective shield that absorbs harmful UV radiation. Once released into the atmosphere, CFCs can remain for decades, and a single chlorine atom can destroy thousands of ozone molecules, causing significant environmental harm.

Imagine a sunscreen that is supposed to protect you from the sun but, instead, every application slowly makes your skin less protected. CFCs work like that—while they seem safe initially, they erode the ozone layer that protects us from harmful UV rays, much like a weakening barrier that should keep you safe from sunburn.

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