Pollution is contamination of the natural environment in a way that causes adversity or change. It can take different forms. Energy or chemical substances. Examples include light, heat and noise. Pollution can be classified basically in to three classes; air pollution, water pollution and land pollution. The waste can take solid, liquid or gaseous forms.
Air pollution is the release of gaseous substances into the atmosphere, toxifying the surrounding air. Substances like gaseous chemicals and smoke enter the atmosphere and change the natural balance of natural air.
Water pollution as the name suggests, is the release of contaminants into water bodies. This endangers aquatic life, and even living things dependent on the same water. Finally, land or soil pollution is when soil is containing contaminants. Fertilizers we use are chemical substances we introduce into soil, which may be carried by water into water bodies, causing water pollution. Substances in air may dissolve in rain water, and when it rains, land is polluted if water sinks, the runoff water enters water bodies and pollutes the water, forming a cycle of pollution.
Industrialization and urbanization have led to increase in pollution. The degree of pollution can be determined by evaluating the effect of the waste in a particular environment, or measuring the quantity of waste. Different places have different levels of pollution (pollution index) across the world according to World Ftealth Organization.
Delhi was mentioned by World Flealth Organization on May this year as the world’s most polluted city having its air twice as toxic as air in Beijing, which had been the world’s most polluted city air for years. The toxicity in the city is said to cause a permanent lung damages, and a projected death of about 1.3 million people each
year. Beijing has high levels of smog, up to over 20 times the recommended level.
Pakistan, India and Iran have very high pollution levels of particle pollution, according to report by WHO on May 2015.
Here is list of the top ten most polluted cities in the world according to WHO on May 2015 report based on pollution Index.
1. Patna, India. PM2.5, ug/m3:149 annual mean. Agricultural waste is the main source of pollution.
2. Gwalior, India. PM2.5, ug/m3:144 annual mean. Pollution here is caused by industrial and other commercial activities.
3. Raipur, India. PM2.5, ug/m3:134 annual mean. Due to commercial and heavy industrial activities.
4. Karachi, Pakistan. PM2.5, ug/m3:117 annual mean. Poor waste management, air pollution and water pollution.
5. Peshawar, Pakistan. PM2.5, ug/m3:111 annual mean. Emissions from industries and vehicles and solid waste combustion.
6. Rawalpindi, Pakistan. PM2.5, ug/m3:107 annual mean. Caused by textile industrial waste.
7. Khorramabad, Iran. PM2.5, ug/m3:102 annual mean. Mainly caused by premature deaths according to the
ministry of health.
8. Ahmedabad, India. PM2.5, ug/m3:100 Annual mean. Industrial waste.
9. Lucknow, India. PM2.5, ug/m3:96. Industrial waste pollution.
The most polluting countries are;
2. United states of America
Today, pollution is one of the world’s major threats to human survival and other living things. Health hazard, global warming and acid rain have very acute impacts on human, causing respiration system problems and death. Ozone layer depletion is also a very adverse effect of air pollution, causing deaths of many people across the world.
Today, Zero waste initiative has been started in countries like Japan with aim of eradicating pollution, to achieve an imaginary zero waste state, where every waste is recycled and reused in same or different purpose.