As cities continue to grapple with air pollution, cycling has emerged as one of the cleanest and healthiest ways to get around. With growing investment in bike lanes, active travel campaigns, cycle to work schemes, and a deeper understanding of pollution's health impacts, cycling is quickly becoming a cornerstone of sustainable urban mobility.

But while cycling is a zero-emission mode of transport, urban cyclists aren’t immune to air pollution. In fact, the very act of cycling — being outdoors, often near traffic, and breathing more heavily — can increase the amount of pollution you inhale. However, there’s good news. Overall concentrations can be less and journeys can be shorter, limiting exposure. Studies consistently show that the health benefits of cycling outweigh the risks, even in polluted cities. And thanks to AirTrack data, we can now understand when those risks are highest—and how to avoid them.

Cycling smarter with AirTrack data

Using over 27,000 cycling records collected via AirTrack across the world, we analysed urban pollution exposure for cyclists around the world. Here’s what we found:

• Average nitrogen dioxide (NO2) concentration while cycling: 28.1 micrograms per cubic metre (µg/m³)
• Average fine particulate matter (PM2.5) concentration: 11.7 µg/m³

These figures are slightly under the World Health Organisation daily limits for PM2.5 and slightly over for NO2.

Pollution levels varied significantly depending on time of day and day of the week:

• Weekday cyclists experienced 36% higher NO2 exposure than those riding on weekends—likely reflecting heavier traffic volumes.
• Early mornings (5–6am) had the cleanest air, with NO2 levels around 19.5 µg/m³.
• Evening rush hour (6pm) saw peak NO2 exposure, reaching 37.5 µg/m³—nearly double the morning minimum.
• Midday riding (11am–2pm) offered a good compromise: cleaner air than rush hour, and convenient for flexible schedules.

Interestingly, late evening rides (9–11pm) did not offer the clean-air advantage some might expect. NO2 levels remained elevated, likely due to lingering emissions and poor atmospheric dispersion after sunset.

The takeaway? When you ride really does matter. Simply shifting your ride away from peak hours can reduce your exposure to harmful pollutants by more than 30%.

Why Route Matters

It’s not just when you ride—where you ride matters too. Proximity to vehicle tailpipes, road congestion, and weather conditions all influence pollutant levels and exposure. Segregated cycle lanes can help reduce exposure, as they move cyclists away from vehicle emissions. Research shows that even a metre or two of separation can cut pollution exposure by about 25%. In London, the introduction of cycle superhighways resulted in a 20% reduction in NO2 concentrations for every metre the roads were moved away from sensitive areas. This really illustrates the potential for infrastructure and planning policies to act as important health interventions.

Cyclists May Breathe More, But Inhale Less

It’s true that cyclists tend to breathe more deeply and frequently than those who travel by car or bus. This higher ventilation rate means they inhale more air per minute, potentially increasing pollutant intake. But here’s the nuance: cyclists also complete trips more quickly.

A 2018 study conducted in Leeds found that cyclists experienced lower air pollution on daily commutes into congested city centres compared to bus drivers or car drivers. The key factor here is the faster travel time - cyclists typically complete a 4km trip in half the time of those travelling by bus or car. This shorter exposure time significantly reduces cumulative exposure, offsetting the increased breathing rate with reduced exposure time.

The concentrations of air pollution around you also matter. As pollutants can get trapped within vehicles, concentrations can be at least 25% higher for different pollutants in a car compared to cycling.

The Health Balance Still Tips in Favour of Cycling

Despite the risks, the health benefits of physical activity outweigh the harms caused by pollution, even in polluted environments. A study by the National Institutes of Health concluded that at global average urban PM2.5 concentrations of 22 μg/m³, the benefits of cycling far exceed the risks. In more polluted areas with PM2.5 levels of 100 μg/m³ or higher, cycling remains beneficial for up to 1 hour 30 minutes per day. When comparing cycling to driving, the advantage is even clearer. Due to shorter exposure durations and increased physical activity, the benefits of cycling outweigh air pollution harms for up to 3 hours 30 minutes per day.

In short: cycling is good for your health—even when the air isn’t perfect.

Air Aware Labs

At Air Aware Labs, our mission is to help cyclists—and all active commuters—make smarter, healthier choices. Our product, AirTrack, provides real-time air quality insights and personalised exposure data, helping users understand their pollution intake and reduce it. By guiding users on where and when to ride, AirTrack empowers people to get the most out of cycling—maximising the benefits, while minimising the harms. Whether you're commuting, training, or just getting some fresh air, AirTrack helps you ride smarter, not just harder.

Abigail Manthous, overseen by Will Hicks