Annual survey by IQAir based on toxic PM2.5 particles reveals some progress in pollution levels in India and China

Only seven countries met the World Health Organization’s guidelines for tiny toxic particles known as PM2.5 last year, according to analysis from the Swiss air quality technology company IQAir.

Australia, New Zealand and Estonia were among the handful of countries with a yearly average of no more than 5µg of PM2.5 per cubic metre, along with Iceland and some small island states.