Air pollution: science shows there's no safe limit – here's how laws must change

Air pollution is the largest environmental risk to public health. Outdoor air pollution causes around four million premature deaths globally each year, while a further three million deaths are linked to pollution indoors – mainly from open cooking and heating fires in developing countries.

The most harmful air pollutants in urban areas are nitrogen dioxide gas (NO₂) and fine particulate matter, often referred to as PM2.5 – particles smaller than 2.5 micrometres that can be inhaled deep into the lungs.…

© La Conversation - mardi 7 septembre 2021