By Haider e Karar
AMONG VARIOUS tangible types of pollution, smoke is the only one that is impalpable. It is a surprising fact that this isolated category of pollution is being neglected in real sense. Smoke which is the mixture of liquid particles, gases and solids, is a silent killer; that has adverse effects on human life in a hushed way. Smoke, whether it exhausts from vehicles or from chimneys of industries is harmful in every aspect. Even it is dangerous too when it exhausts from “sheesha” (flavoured smoking) or when it is produced artificially in the music concerts.
Usually smoke is the result of incomplete combustion which originates from fuel, oxygen and source of ignition also called the fire triangle. During the process of combustion, number of gases evolved; smoke is the unburned portion of these gases. Smoke normally consists of COx, SOx, NOx, ash, tiny particles and moisture. Industrial & vehicular smoke has diverse compositions because of the different types of fuels used in the process and internal combustion engine respectively. Every component of smoke is like a poison which affects human beings unsympathetically. Its constituents depend upon the type of the burning fuel and these can vary as the source of ignition would be changed.
Carbon monoxide (CO) is very toxic for respiratory system; it consumes the oxygen in lungs. Hemoglobin has greater affinity for carbon monoxide than oxygen. So, CO coalesces with hemoglobin and cut down the oxygen-carrying capacity of blood. This results in blurry vision, unconsciousness, headache and death due to suffocation.
Carbon dioxide (CO2) concentration in the environment is plausible to increase the temperature of the atmosphere. CO2 allows the short wavelength to pass through it but entraps the longer wavelength; infra-red radiations (heat waves) reflected by the earth’s surface. These entrapped heat waves heats up the atmosphere resulting in Green House Effect. The inordinate heating of earth and its atmosphere causes the global warming. That has significant impacts on all the living beings.
Sulphur dioxide (SO2) is a temperate to strong irritant. Inhalation of SO2 smacks the nose and throat while little amount approaches the lungs and damages the respiratory system. It reduces the productivity of plants and crops and turns the plants greenish to yellow. It also increases the rate of corrosion in metals.
Nitrogen oxides are a group of different gases with the varying proportions of nitrogen and oxygen. It not only has dreadful effects on environment but on human health also. It causes the acid rain and imparts the global warming. It hinders the growth of plants and combines with the other gases of the environment to make toxic chemicals which ultimately pollute the environment. Small inhalation of nitrogen oxides results nausea, shortness of breath, irritation in eyes and so on.
Besides these poisonous gases, very fine particles are also present in smoke. These fine particles are as small as less than 1µm in diameter. People living in the vicinity of sugar industry would be experiencing such kind of particles and black ash. These particles are invisible and travel for miles in the air and then fall down. House wives who clean their homes, normally face the problem of black ash in the milling season. These very small and fine particles of smoke can penetrate inside the lungs. These fine particles themselves, or by forming a compound with other air pollutants can shoddily damage the internal organs of the body. Where there is a short-term vulnerability to smoke, these particles are the most substantial threat to public health.
The above mentioned gases are those which are very common and exhaust from the industries either in the form of flue gases or hidden in the smoke in small traces. In smoke two components – CO and tiny fine particles – are very dangerous. Normally only smoke does not have as much adverse affect on human being and if someone could affected by the smoke can recover in a short period of time because Allah Almighty made a natural system in the human body which automatically filters the air through inhalation. But when this smoke combines with other pollutants in the atmosphere, it becomes hazardous. For example, the industrial smoke, having a different composition from the smoke exhausted by vehicles; combines to form a complex mixture of gases and become more poisonous not only for the environment but also for the people who spent maximum time in that particular environment. Such people have serious health problems and they take time to recover otherwise mostly become patient for rest of their life.
These are the reasons; smoke is called a silent killer because it kills leisurely. The difficulty is that smoke is the mixture of poisonous gases. For every single gas there is a safety data sheet but for the mixture of gases and when we do not know the exact proportions of all these, it is very difficult to nominate the precautions.
The only solution of this problem is tree plantation as much as we can because plants keep the environment clean and safe. As well as industrialists should install micro sieves in the path of smoke and make sure the complete combustion using in the process running. They should also choose the good quality fuel with high calorific value and less moisture contents. It should be remembered that clean environment is our responsibility and everyone should own this.