MCQ Detailed View

Air pollution in big cities is a serious environmental problem, and certain metals contribute significantly to it. One of the most harmful metals is Lead (Pb). Lead pollution occurs mainly due to vehicle emissions, industrial activities, and the burning of fossil fuels. Historically, leaded gasoline was the primary source of atmospheric lead, and although its use has decreased, lead still enters the air from other sources such as battery manufacturing, smelting, and waste incineration.

Lead is highly toxic even in small amounts. When inhaled or ingested, it can accumulate in the human body and cause serious health problems, including brain damage, kidney disorders, anemia, and developmental issues in children. Lead pollution is especially dangerous in urban areas, where dense traffic and industries increase the exposure risk.

Other metals like Cadmium (Cd), Copper (Cu), and Chromium (Cr) can also contribute to pollution, but their atmospheric presence is usually less significant compared to lead in city air. Cadmium is more associated with industrial emissions and battery disposal, chromium with industrial processes, and copper mainly with corrosion or metal production.

Lead particles in the air can attach to dust and fine aerosols, which are easily inhaled by humans. These particles settle slowly, so lead pollution remains persistent in urban environments, contaminating soil, water, and the food chain.

Reducing lead pollution requires strict environmental regulations, replacing leaded fuels, proper waste management, and monitoring industrial emissions. Awareness about lead pollution is crucial for public health and environmental safety.

Therefore, the correct answer is Lead (Option 3), which is the metal most commonly responsible for air pollution in big cities.