Household sewage and detergents can pollute water sources if not properly treated, as they release chemicals like ammonia and organic acids that harm living organisms. Vehicle and industrial exhausts as well as smoke release gases into the air that cause pollution, with automobile and plane exhaust containing petroleum gases and smoke containing carbon dioxide and water vapor. Biological pollutants such as pollen, bacteria, and fungal spores can also cause allergic diseases. The document provides tips for reducing pollution like using public transportation, saving water and energy, and planting trees.