Which of the following are primary pollutants?

(1) Carbon monoxide (CO)

(2) Sulphur oxides (SO₂)

(3) Volatile Organic Compounds (VOCs)

(4) Nitric Oxide (NO)

(5) CFC's

(6) Radioactive pollutants

Select the correct answer using the code given below

The correct answer is Option 4: 1, 2, 3, 4, 5 and 6

Key Points

• Carbon monoxide (CO): A primary pollutant released directly from sources like vehicle exhausts and industrial emissions. It is a colorless, odorless gas that poses serious health risks.
• Sulphur oxides (SO2): These are primary pollutants primarily emitted from burning fossil fuels (such as coal) and certain industrial processes like oil refining.
• Volatile Organic Compounds (VOCs): VOCs are emitted directly from sources such as vehicle exhausts, industrial emissions, and solvent use. They contribute to air pollution and are involved in the formation of ground-level ozone.
• Nitric Oxide (NO): A primary pollutant produced during combustion processes, such as vehicle engines and industrial activities. It contributes to the formation of smog and acid rain.
• CFCs (Chlorofluorocarbons): These compounds are directly emitted into the atmosphere from products like refrigeration units, air conditioners, and solvents. They contribute to ozone layer depletion.
• Radioactive pollutants: These are pollutants such as radon, uranium, and other radioactive materials that are released directly into the environment from nuclear power plants, mining activities, and natural sources.

Important Points

• Primary pollutants are those that are directly emitted into the air, water, or soil from a source, whereas secondary pollutants form as a result of reactions in the environment.
• All the listed pollutants (CO, SO2, VOCs, NO, CFCs, and radioactive pollutants) are examples of primary pollutants that directly affect air quality and environmental health.

Additional Information

• Secondary pollutants: These are formed in the atmosphere as a result of chemical reactions between primary pollutants, such as ground-level ozone and smog.
• Control measures: Reducing primary pollutants can help mitigate secondary pollution, and measures such as using cleaner fuels, adopting emission standards, and using catalytic converters can help control their release.