PM2.5 air pollution, population exposed to levels exceeding WHO guideline value (% of total)

Definition

Percent of population exposed to ambient concentrations of PM2.5 that exceed the WHO guideline value is defined as the portion of a country’s population living in places where mean annual concentrations of PM2.5 are greater than 10 micrograms per cubic meter, the guideline value recommended by the World Health Organization as the lower end of the range of concentrations over which adverse health effects due to PM2.5 exposure have been observed.

Methodology for Environment indicators

Environmental indicators cover emissions, land use, biodiversity, and natural resources. Emissions data is often produced by international scientific consortia (EDGAR, Global Carbon Project) and typically lags 2–3 years due to the complexity of fuel- and process-level accounting. Per-capita metrics reveal a different story than absolute totals — small wealthy countries can have high per-capita emissions while contributing little to the global total.

How to interpret

• Always check the unit and reporting year before comparing values across countries.
• NULL or "Not available" means the World Bank did not publish a value — we never estimate.
• Year-over-year changes can be driven by methodology updates, not just real economic shifts.