Photochemical smog: Digging our own grave

Photochemical smog causes many diseases and disorders in human body. Nitrogen oxide causes heart and lungs disorder as well as reduces the power to fight against these disorders.

In the presence of daylight when many primary pollutants produced from the burning of carbon material react with each other to form secondary pollutants which creates a haze type situation in the atmosphere known as photochemical smog.

From burning of carbon materials like fuel in the automobiles release oxides of nitrogen in the atmosphere. There is more release of these chemicals in the early morning due to heavy traffic. After the release these chemicals reach in the atmosphere and converted into their higher forms like nitrogen dioxide, nitrogen trioxide etc.

The nitrogen trioxide is converted into dinitro-pentaoxide by reacting with other nitrogen oxides. Then these all pollutants react with each other in the presence of daylight and form many other type of dangerous secondary pollutants.

Nitrogen oxides present in the atmosphere then start breakdown as the sun rises, resultantly the ozone is produced and at the same instant react with volatile carbon compounds. High temperature causes more formation of photochemical smog as there is more speed of nitrogen oxides breakage at high temperature.

There are many other factors like day length, rainfall, wind speed, topography of an area and intensity of burning of carbon material affects the formation and time of stay of photochemical smog.

Effects of photochemical smog

Human health and the other components of the environment are badly affected by photochemical smog. The materials that are used on the buildings are also damaged by its activity. Clouds of brown color are the only effect of photochemical smog which can be seen through naked human eye.

Chemicals like nitrogen oxides, ozone and other secondary pollutants affect the growth and development of plants. Clouds formed in the atmosphere restrict the sunlight to intercept by the plants which affect the rate of photosynthesis and production of assimilates within the plant body are reduced due to disturbance in their metabolic activity.

Photochemical smog causes many diseases and disorders in human body. Nitrogen oxide causes heart and lungs disorder as well as reduces the power to fight against these disorders. Volatile organic compounds result in eye infection, respiration problems and also cause several type of skin cancers. Ozone also cause cough, puffing, breathing problems, lungs disorders and eye infection.

In animals, photochemical smog causes respiratory disorders, less food intake, milk fever, less milk production with low fat content and decrease in body temperature.

Many compounds which are used in routine life are also affected under photochemical smog like cracks are formed in the rubber made things, textile products and paint. Historical things in the museums are also being damaged under the reactions of photochemical smog.

Mitigation measures

To reduce the formation of secondary pollutants in the atmosphere it is necessary to reduce the primary pollutant emission. Nitrogen oxides should not be emitted directly into the atmosphere for this, convertor should be used in industries and automobiles which can convert the nitrogen oxides into the gaseous form of nitrogen and oxygen.

There should be such type of engines in which less use of air is made possible because nitrogen comes from air during combustion it is not present in fuel. Temperature should also be lowered with in the engine by introducing an alternative design or extra chamber in your car or industry. By using the alternatives of petrol and diesel as a fuel such as use of compressed natural gas and liquid pressed gas, is a good alternative of fuel.

In our daily routine life, we should take precautionary measures so that the emission of pollutants in the atmosphere can be made minimum.

As precautionary measures, a common citizen should:

1. Keep his car serviced in time;
2. Replace old vehicle with a new and more efficient;
3. Instead of using car use bus, train or bike (public transport) to travel so that there’ll be less pollutant emission;
4. Electrical appliances used at home should also be efficient in using energy to avoid its excess use;
5. Turn off the appliances which are not in use or not necessary, instead of stand-by;
6. Go for renewable energy resources,
7. Use minimum wood at home for fire,
8. Always wear warmer clothes in winter instead of using a heater to make your micro environment hot.

At national level awareness seminars, workshops and walks should be organized about all the environmental pollutants, their formation, emission and their dangers to the human, animals, plants and environmental sustainability so that we can make our country pollution free.

This article is collectively written by Nasir Ali1, ImdadUllah1, Nadeem Akbar1, Muhammad Rashid Fayyaz2, and Muhammad Ishfaq1. They belongs to 1 Department of Agronomy, University of Agriculture Faisalabad; and 2 Department of Parasitology, University of Agriculture Faisalabad.