8.3 Urban air pollution

• NOx, sulfur dioxide, carbon monoxide, particulate matter

• PM2.5 (≤2.5 µm), PM10 (≤10 µm)

• Natural: forest fires, dust, volcanic eruptions

• Anthropogenic: burning for clearance, fossil fuels, construction dust

• Most common urban air pollutants

• Primary: PM2.5, PM10, CO, SO₂

• Secondary: tropospheric ozone

• Public transportation, cycling infrastructure, trees

• Green walls, catalytic converters, pedestrianized areas

• NOx + SO₂ react with water and oxygen

• Produces nitric and sulfuric acid

• Terrestrial: soil leaching, toxification, foliage damage

• Freshwater: toxicity, impacts on fish/invertebrates

• Buildings: corrosion of marble, limestone, steel

• Human health: tissue damage, lung inflammation

• Alter human activity (alternative energy)

• Control at release (scrubbers, catalytic converters)

• Restore damaged systems (healthcare, lake treatment)