Why Do Some People Who Don't Smoke Contract Lung Cancer?

Smoking is the biggest cause of lung cancer. Cigarette smoke tar particles can produce DNA mutations in lung tissue. In the UK, however, 6,000 people, who have never smoked, die of lung cancer each year. Outdoor air pollution appears to cause this 10% of annual lung cancer deaths in Britain. Most of the country's current air pollution comes from the exhausts of petrol and diesel-fuelled vehicles. These fumes also contain particulate matter (PM2.5). PM2.5s dont, however, cause DNA mutations in the lungs. So, how can air pollution be linked to lung cancer? A team from London's Francis Crick Institute have shown that the fine particulates in car fumes, activate dormant (non-active) lung cell mutations (https://www.theguardian.com/science/2022/sep/10/cancer-breakthrough-is-a-wake-up-call-on-danger-of-air-pollution). This activation converts latent lung cell mutations into full-blown cancers. Globally, 300,000 of 2019's lung cancer deaths have been attributed to Pm2.5s. Air pollution needs to be rapidly reduced, to save human lives. Diesel is the bigger problem, as it produces many more of the fine particulates.