How Has Air Pollution Impacted Societies Since the Industrial Era?

Clean air is essential to human life and health. Nature freely provides us with clean air from a vast atmosphere composed of approximately 21% of oxygen (O 2 ), 78% of nitrogen and other gases. However, over the past century, anthropogenic activities have spread tons of air pollutants into the atmosphere that contaminate the whole biosphere and adversely affect human health. By 2022, more than 99% of the global population was exposed to polluted air ( WHO, 2022 ). In over 6000 cities in 117 countries, people still breathe air that contains high levels of pollution containing particulate matter, heavy metals, organic compounds, and nitrogen dioxide, with low and middleincome countries particularly affected (WHO, 2022). The importance of air quality to human health has been recognized for centuries, including in an ancient treatise of Indian Traditional Medicine, Ayurveda ( Vyas, 2022 ).