Air Pollution

Air pollution is the presence of harmful substances—such as gases, particulates, and biological molecules—in the Earth's atmosphere that cause adverse effects on human health, other living organisms, and the natural environment. Key pollutants include carbon monoxide ($CO$), nitrogen oxides ($NO_x$), sulfur dioxide ($SO_2$), and volatile organic compounds ($VOCs$). These contaminants can originate from natural sources like volcanic eruptions or, more significantly, human activities such as industrial emissions, vehicle exhaust, and deforestation.

Legally, under Section 2(a) of the Air (Prevention and Control of Pollution) Act, 1981, it is defined by the presence of any "air pollutant" in the atmosphere at concentrations that tend to be injurious. This imbalance disrupts ecological cycles and contributes to global issues like acid rain and climate change.