The Unequal Geography of Human Air Pollution Exposure
The poorest half of humanity breathes 66% of the world's fine-particle exposure above the WHO guideline. Exposure peaks not in the poorest countries but in lower-middle-income ones, where industry, dense cities and solid-fuel cooking coincide: their population-weighted average is 42.5 µg/m³, against 12.5 in high-income countries. Since 2010 three in four high-income countries have cleaned their air, against fewer than half of lower-middle-income ones.