Introduction

Atmospheric pollution refers to the contamination of the atmosphere by gaseous, liquid or solid wastes. Pollution mostly occurs in densely populated areas and directly results from human activity. Pollution has a detrimental effect on all life forms and poses a severe threat to the climate. Climate change can have serious consequences that adversely impact the natural habitats of several species.

Six Most Critical Atmospheric Pollutants

1. Carbon monoxide. It is an odourless, invisible gas that can cause sudden illness and death if inhaled. It is therefore known as a silent killer. Burning of gasoline, kerosene, wood, coal, natural gas, propane, oil or methane produces carbon monoxide.
2. Nitrogen dioxide is one of the most highly reactive gases known as nitrogen or nitrogen oxides. Some examples are pollution from cars, trucks and buses, power plants and off-road equipment. 
3. Atmospheric ozone can be either good or bad for health, depending on where it is. The stratospheric ozone is beneficial because it protects living beings from ultraviolet radiation from the sun. However, ground-level ozone is bad for health because it can lead to various health problems like coughing, scratchy or sore throat, breathing difficulties and increased instances of asthma.
4. Particulate matter comprises solid particles and liquid droplets suspended in the air. In general, any burning or dust leads to particulate matter, such as burning woods, fireplaces, stoves, and vehicular pollution. Lead is another major pollutant. The main sources of lead pollution are ore and metal processing and piston-engine aircraft operating on leaded aviation fuel. Other sources include incinerators, utilities and lead-acid battery manufacturers. Lead can affect our nervous system, kidney function, immune system, reproductive and developmental systems and cardiovascular system.
5. Sulphur dioxide is a colourless reactive gas produced when fuels containing sulphur dioxides such as coal and oils are burned.

Causes of Atmospheric Pollution:

Burning of Fossil Fuels

The main reason for atmospheric pollution is burning fossil fuels such as coal, oils and gasoline. They release high levels of carbon dioxide and other toxic pollutants into the air. Inhaling these noxious gases causes serious ailments, including major cardiac and respiratory illnesses.

Industrial Emission

Industrial emissions are another prominent cause of air pollution. For example, particulate matter 2.5 and 10, sulphur dioxide, nitrogen dioxide and carbon monoxide are the chief industrial pollutants. These cause irritation in the eyes and throat and breathing difficulties, often leading to chronic illness. 

Indoor Atmospheric Pollution

Usage of toxic chemical-based products containing volatile organic compounds ( VOCs), insufficient ventilation, uneven temperatures and humidity levels can lead to indoor air contamination. Other factors contributing to indoor pollution include smoking and the usage of air conditioners.

Wildfires

Unchecked climate change has led to increasing incidents of wildfires that severely impact atmospheric pollution. The burning of stubble and farm residue adds to this issue, increasing particulate matter 2.5 in the atmosphere. On mixing with other harmful substances like gases released by harmful chemicals and pollen, this results in smog that degrades the air quality and causes a host of health problems. 

Transportation

Vehicular pollution contributes significantly to atmospheric pollution, especially in urban areas. Healthcare experts opine that inhaling gasoline fumes is as harmful as smoking 10 cigarettes a day. Vehicles emit carbon monoxide, hydrocarbons, nitrogen oxides and particulate matter, all of which damage the ozone layer, which protects the earth from hazardous rays.

Open Burning of Garbage

The open burning of garbage is much more harmful to the environment than one may think. The open burning of waste can lead us to various health problems like cancer, liver issues, mess with our immune system, and affect our nervous system.

Agricultural Activities

Agricultural activities also have a severe impact on increased atmospheric pollution. Pesticides and fertilisers are the primary sources of contamination. These are either sprayed or mixed with water and eventually seep into the earth. This causes soil degradation in the long run, and crops thus grown have low nutritional value and can cause numerous health issues.

Effects of Atmospheric Pollution

Harmful to Human Health

•  According to the World Health Organisation, close to seven million people die each year due to atmospheric pollution. Around 4000 people died in a few months following the severe smog event of 1952 in London. Ground-level ozone causes breathing difficulties, sore throat, coughing, lung diseases and sometimes, permanent lung damage.
• Short term exposure to ozone can cause coughing, wheezing, headache and dizziness.
• Long-term exposure to ozone can cause congenital disabilities; liver, spleen and blood disorders; cancer and even death.

Harmful to Animals and Plants

Both wild and domestic animals can suffer the ill effects of atmospheric pollution. Respiratory system damage is the most common effect on animals; skin irritation and neurological problems also occur frequently.

Atmospheric pollution adversely impacts plant and crop growth. Acid rain, lead toxicity and nitrogen oxides change the chemical nature of the soil and plants are robbed of the nutrients they need to grow and survive, affecting agriculture, forests and grasslands.

Acid Rain

The burning of fossil fuels releases sulphur and nitrogen oxides into the air. Acid rain is formed when sulphur dioxide and nitrogen oxide mix with the water droplets in the air to make sulphuric and nitric acid. Winds usually carry these pollutants across thousands of miles, and they fall on the earth’s surface as acid rain. This ruins the vegetation and increases soil acidity levels. Acid rain also damages the buildings and other structures and can make the foundation unstable.

Reduced Sunlight

The high level of particulate pollution from all types of burning reduces the amount of sunlight that reaches the surface and sometimes even changes the appearance of the sky. Decreased sunlight directly impacts photosynthesis and slows down plant growth. Also, crops lose their nutritive value. Apart from reducing visibility, hazy skies can potentially impact the weather and climate.

Damage to the Ozone Layer

Atmospheric pollutants erode the ozone layer. Chlorine atoms released into the atmosphere cause holes in the ozone layer. The depleted ozone layer cannot block the harmful UV radiation, thus putting all living creatures at risk. Constant and increased exposure to UVB leads to skin cancer in humans and causes numerous other problems to all life forms.

Effects of Greenhouse Gas Pollution

Climate change is the result of greenhouse gas emissions. Rapidly changing ecosystems make it difficult for flora and fauna to cope and adapt. Several species have vanished and many more are on the brink of extinction. The carbon dioxide emissions dissolve in seawater, causing ocean acidification and affecting the marine ecosystem. Acidification directly impacts many marine species, several of which face difficulties in growing shells and skeletons. Ocean warming, glacier melting, and extreme weather conditions are examples of how the greenhouse effect changes the climate and threatens ecosystems globally.

Conclusion

Atmospheric pollution is a major environment-related health issue, especially for children and elders. Often it leads to major respiratory issues, heart attacks, disability in children and sometimes even death. Drastically reducing atmospheric pollution is the need of the hour.