Sun beating down

Is the UK heatwave bad for air pollution?

The summer heatwave has seen the mercury pushing 35°C. We all know to slap on the suncream. But the heatwave may also have health implications for your lungs.
  Published:  27 Jul 2018    |      3 minute read

Revelling in the sunshine? Sweltering at your desk? Everyone knows the potential health risks during a heatwave. So we gear up with sun cream to protect our skin. And we stay extra hydrated. But what does the heat do to air quality? What about our lungs?

Blue sunloungers and blue umbrellas on white sands on a hot day.
People on the beach during summer
Credit: Jonny Clow


The hot and sunny weather can lead to increased air pollution in a number of ways, from boosting ground level ozone pollution to increasing the risk of harmful pollutants from wildfires.

See below for Friends of the Earth’s explanation of the ways that the UK heatwave is affecting the air we breathe.

Sunshine and heat creates more ground level ozone pollution

Ah, the sunshine. It can be a glorious thing. It gives us a vitamin D boost and dreaming about it helps us get through long winters. Unfortunately, it also combines with vehicle emissions, including nitrogen dioxide, to form ground level ozone.

Our planet’s ozone layer, located high up in the stratosphere, is an important blocker of harmful UV rays. Back at ground level though, it’s a less welcome guest.

When ozone builds up at ground level it can irritate and inflame the lungs, as well as irritating the eyes, nose and throat. It can also go on to cause severe air pollution episodes or smog.

Our air gets lazy in a heatwave

It’s not just us humans who can be made lazy and slow-moving in the heat. Air too can be made stagnant by increasing temperature.

This lazy air means that a cocktail of pollutants get stuck at ground level. Pollutants like nitrogen dioxide – the toxic gas that inflames the lining of the lungs. And dangerous fine particulate matter that can even get into our bloodstream – as well as deep into our lungs.

A queue of cars with excessive exhaust fumes
A queue of cars with excessive exhaust output


Get polluting vehicles off our roads by signing our petition to ditch diesel

The heatwave is wreaking havoc on hay fever sufferers

Let’s spare a thought for those with hay fever for whom summer is a time of itchy eyes, runny noses and regular trips to the pharmacy for anti-histamines.

Young white woman in field blowing her nose.
Vehicle fumes can prevent pollen escaping into the upper atmosphere


The current heatwave has seen high pollen levels at the same time. Vehicle fumes can form a barrier that traps pollen and prevents it from escaping into the upper atmosphere.

The countryside is certainly alive with plants and pollen. But because air pollution traps pollen at ground level (close to our poor noses and eyes) city dwellers are more likely to suffer from hay fever.

Wildfires and smoke pollution

Wildfires may be something we associate more with places like Greece, Australia and California. However, the recent hot weather and shortage of rain in the UK has dried out huge swathes of vegetation. This has been fuelling a wave of wildfires slightly closer to home.

forest fire at night with few trees
Credit: Thinkstock


Wildfires such as that at Denshaw in Greater Manchester pose a huge risk to public health. The immediate danger of a fire is one thing but huge clouds of smoke can drift for hundreds of miles.

Studies in the United States have found that wildfires can lead to spikes in dangerous fine particle air pollution. This can significantly raise air pollution levels in cities up to 100 miles away. A team of scientists in the UK is currently testing smoke samples gathered from recent wildfires to better understand the implications for the air we breathe.

Let’s talk about barbecues

We all love a good barbecue. Food just tastes better when you’ve cooked it outside. Holding a drink in one hand and giving everything a random poke or flip (like we know how to barbecue) with the other.

The hot and sunny weather understandably makes millions of us want to get out there and barbecue away. We’re not going to tell you to jump off the barbecue train, but your choice of fuel can have big implications for air quality.

People picnicking and barbecuing in park in hot weather
Outdoor barbecuing in the summer
Credit: Rob Bye


Smouldering coals are seen by purists as the way to go. This old-school barbie fuel releases clouds of harmful pollutants such as particulate matter into the air. Gas is the cleaner alternative when it comes to air quality. It’s also easier to light and control the temperature, meaning less barbecue lighting rage on the road to your tasty morsels.

If the heat has inspired you to invest in a barbecue, try to resist going for a disposable one. Not only are these often fuelled by coal, they’re smothered in single-use plastic. Buy yourself a long-term one you can be proud of.

Catering barbecue showing hands of chef


And then bask in the glory as you exhibit your shiny new grill during the mandatory chat around the barbie this summer.

Go for an outdoor electric grill if you really want to be eco.

Check out our hints and tips to throw the ultimate eco-friendly barbecue this summer.