Air pollution is even more dangerous than previously thought, the World Health Organization (WHO) has warned, as it slashes maximum safe levels of key pollutants such nitrogen dioxide.
An estimated seven million people die prematurely each year from diseases linked to air pollution, the WHO says.
Low- and middle-income countries suffer the most, because of their reliance on fossil fuels for economic development.
The WHO puts air pollution on a par with smoking and unhealthy eating.
It is urging its 194 member states to cut emissions and take action on climate change, ahead of the COP26 summit in November.