What's my local air quality index – and why is it important?

An early and intense start to the wildfire season in Canada has led to public health authorities in New York, Toronto and Ottawa all issuing warnings about air quality.

Air pollution in New York hit the worst level in recent history on 8 June after intense wildfires in Canada sent up huge amounts of smoke into the atmosphere.

Pollution levels were five times above the national air quality standard – and were temporarily the worst of any urban centre in the world.

Continued wildfires are predicted in the region amid long-term forecasts of warm and dry weather. On a longer-term basis, as the climate crisis drives up temperatures and increases droughts, wildfires are becoming more likely. This means smoke and its impact on air quality will remain a persistent and growing concern around the world.

Wildfires release fine particulate matter which spreads over hundreds of kilometres. These tiny particles can aggravate asthma, cause lung diseases and heart attacks, and lead to premature death.

Globally, air pollution is responsible for about 7 million deaths a year – or about 10% of all deaths.

The combined influence of climate change and land use change is predicted to lead to a 14% increase in extreme fires by 2030, rising to 30% by 2050 and 50% by 2100, according to a report by the UN Environment Programme.

As the World Economic Forum’s Global Health and Healthcare Strategic Outlook highlights, air-pollution-related deaths will not be the only health implication of climate change, with illnesses such as malnutrition, malaria, diarrhoea and heat stress all set to increase. The cost of direct damage to health is estimated to be around $2-4 billion annually by 2030.

On an individual level, there are a number of steps that can be taken when air pollution levels are exceptionally high. These include not making unnecessary car journeys, and avoiding using wood stoves or burning things like trash or garden waste. Other steps sometimes advised include staying inside, avoiding prolonged or heavy exertion, and keeping medication to hand if you have asthma or a heart condition.

The Air Quality Index allows you to see how polluted the air near you is on a daily basis, including what the health effects could be. It grades pollution levels and gives advice on the appropriate action to take.

Many people are particularly at risk from poor air quality, including those with pre-existing heart or lung conditions, children, and older adults. However, even if you are otherwise healthy and don’t fall into any of these categories you should still adjust your activities when pollution levels are high.