A new study has upended the way researchers think about how air pollution causes lung cancer. The work cracks open a whole new way of thinking about certain cancers and how to treat and even prevent them. It also suggests environmental agencies may have good reason to impose much stricter limits on air quality.
Scientists typically describe carcinogens in terms of the havoc they wreak on our genome. UV exposure from sunbathing damages DNA in skin cells, and over time cells with mutations can accumulate and eventually grow with abandon. Smokers breathe in chemicals that can cause widespread mutations and alterations to DNA that can lead to lung cancer. Public health groups make sure that people know that damage is preventable — slather on the sunscreen or toss the pack of cigarettes — and drug companies have come up with medicines that target those mutations if they ignore that advice.
But researchers at the Francis Crick Institute found something different going on in lung cancer caused by pollution. Fine particles in dirty air, known as PM2.5, aren’t directly tinkering with our DNA. Instead, they are setting off a chain reaction that causes tumors to grow.
