Pollutants and Their Impact

Indoor and outdoor air pollution cause approximately 8 million deaths per year, making premature death’s most significant environmental cause. 4.2 million of these deaths are caused by outdoor sources such as vehicles and industrial emissions; 3.8 million are caused by indoor sources such as household fuels and fires.

Air pollution is one of the severe causes which impact the health and wellbeing of everyone in our communities, including children. We must continue to work together to address this.

People can be exposed to air pollution in many different ways. The most significant contributors are vehicles, factories, power plants, burning wood and trash, wildfires, and backyard grilling minus the cover! 

You probably picture big cities and factories when you think of air pollution. But, the numbers paint a very different picture. Many people don’t realise that household emissions—the smoke from cooking and heating your home—are the most deadly.

Types of Air Pollution

There are two main types of Air Pollution they are :

• Primary Pollutants

• Secondary Pollutants

1. Primary Pollutant

Primary pollutants enter the air directly. Carbon dioxide is released when fossil fuels burn. Nitrogen oxides form when nitrogen and oxygen combine at high temperatures. It occurs in hot exhausts from vehicles, factories, and power plants. Sulphur oxides are produced when sulphur and oxygen combine at high temperatures in smokestacks from fossil fuel-fired power plants or industrial boilers emitting pollutants such as sulphur dioxide or SO₂, carbon dioxide CO₂, and ash particles that are harmful to us if inhaled. 

Toxic heavy metals include mercury and lead. Heavy metals are already present in the environment. Still, their increased presence can eventually accumulate these elements in ecosystems essential to our survival, like those found in oceans, freshwater bodies, and soil, affecting wildlife habitats. Air pollution can stem from both natural and artificial causes. It can be released as gases and particles into the air through various processes.

2. Secondary Pollutant

The main types of secondary pollutants are photochemical smog and acid rain. Photochemical smog forms when certain pollutants react in the presence of sunlight. It is a brown haze in the air, and it consists mainly of ozone (O₃). Ozone near the ground is a pollutant; however, ozone high in the stratosphere protects Earth from dangerous ultraviolet radiation. In addition, acid rain forms from nitrogen oxide and sulphur dioxide, two primary pollutants. It occurs naturally but can also be caused by industrial pollution.

Effects of Air Pollution on the Environment

Air pollution impacts human beings and affects the entire surrounding and animals and plants. Let us know about the effects of Air Pollution on the Environment.

• Harms Human Health

Air pollution introduces chemicals, particulate matter, or biological material that cause harm or discomfort to organisms. The atmosphere is a complex natural gaseous system essential to support life on Earth. It is a mixture of nitrogen ( 78% ), oxygen ( 21% ), water vapour, and other gases. Air pollution, also called air contamination, introduces chemicals, particulate matter, or biological materials that cause harm or discomfort to humans or other living organisms in the atmosphere.

• Harms plants and animals

Pollution can have many adverse effects on plants. Air pollution can damage plants directly by affecting their ability to breathe through tiny pores in plant leaves called stomata. Ozone pollution damages stomata by attacking their membranes and interferes with their ability to absorb carbon dioxide. The result is that most types of plants lose the ability to create food from light energy. The combination of acid rain and nitrogen oxides in the soil also decreases plant growth by changing soil pH so it cannot absorb nutrients for plant use.

• Cause Acid Rain

Acid rain forms when sulphur dioxide and nitrogen dioxide mix with water droplets in the atmosphere to make sulfuric acid and nitric acid. It happens when there is a lot of pollution from fossil fuels. Acidic rain is harmful to trees, lakes, and buildings. It can kill fish and birds, damage statues and other stone buildings, cause cars to rust faster, corrode metal bridges, hurt rice crops and marble statues, etc. Acid rain causes damage to the environment by changing the pH of the soil, water, and air. It is a costly problem that harms plants, animals, and buildings. Acid rain also damages marble, limestone, and other natural materials made of calcium carbonate.

• Reduces Sunlight

Particulate pollution from all types of burning directly impacts the amount of sunlight reaching the surface and, in many cases, changes the appearance of the sky. A reduction in sunlight affects rates of photosynthesis and slows forest recovery and leaf growth in forests. The particles reflect light that plants would typically absorb. This indirect effect can significantly impact agriculture, reducing crop yields.

Conclusion

Air pollution is a complex phenomenon. It can produce material, biological and human health effects. The kinds of pollutant effects that most affect our daily lives are those on materials and vegetation. However, we should recognize that these can also affect animals and humans through indirect pathways. 

The majority of the population is not exposed to air pollutants at levels that threaten material or human health. However, the general public’s exposure may be greater than in the past because of increased emissions from motor vehicles and utility sources. The concentration of pollutants in outdoor air presents a health hazard to the general population. However, it is difficult to apportion causes of death and disease between different agents. More research is needed to estimate better the burden of disease attributable to outdoor air pollution.