A startling percentage of people who don’t smoke are diagnosed with lung cancer every year, and these are some of the reasons why, says Dr Charleen Muller [photo], clinical and radiation oncologist at Cancercare’s East London Oncology Centre.

The person who lifts a cigarette to their mouth and puffs away at the chemical-infused smoke is standing in the direct lung cancer firing line. According to Cancer Research UK, smoking can cause up to 15 types of cancer, including lung and larynx, and 15% of smokers are likely to get the disease. However, statistics have also found that 10-15% of non-smokers are likely to get cancer too, especially women. This hardly seems fair if you’ve never smoked, eat all your vegetables and run 20km a day, but the reality is that lung cancer isn’t just about smoke.

Non-smokers are people who have never smoked or who have had less than 100 cigarettes in their lifetime. They are the ones affected by second-hand smoke that regular cigarette users leave behind. “While this is a pervasive problem, some of the biggest causes of lung cancer aren’t associated with cigarettes”, says Dr Muller from Cancercare. According to Dr Muller, this cancer is more likely to come from the environment and the pollutants made by man.

Air pollution

According to her, there is significantly more air pollution, and recent studies have shown that the pollution caused by traffic has increased by more than 15-20% over the past 15-20 years. Not only does the rise in nitrogen oxide pose a risk to people driving or living in traffic, but it’s turning the morning run into a deadline pastime. Today, runners would be better off doing their training on a treadmill in the airconditioned gym or taking to the parks where leaves can reduce the impact of fumes.

“In addition to car and cigarette smoke, lungs are subjected to compounds such as chromium and arsenic in the manufacturing and car paint industries. These toxic compounds increase the risk of lung cancer as they cause mutations in the tissue. One of the most infamous causes of lung disease and cancer is asbestos – a group of minerals used in the building industry. Most buildings have had the material removed. However, it remains a concern for those who work in or around asbestos infected areas,” says Dr Muller from Cancercare.

“Uranium is another mineral that damages the lining of the lung”, she says. “Uranium not only affects miners in the actual mines, but it is present in the soil and groundwater and has been known to accumulate in homes. Radon gas, a by-product of uranium, is also a major cause of lung cancer. It isn’t toxic in minute quantities, but long-term exposure at high levels will make a person sick”, according to Dr Muller.

Use smoke-free coal

Dr Muller says that while many people won’t come across uranium or radon gas on their daily commute, it is important to recognise how severely atmospheric pollutants can impact on health and wellbeing. Vehicle exhausts, power plants, wood stoves and coal fires all release particles that embed in the lungs and cause mutations, illness and cancers. “For those who live in homes that use fires for warmth and cooking, it is essential that they use smoke-free coal as that will help reduce the risks and increase health.”

There are also some causes that are out of most people’s control – genetics and previous bouts of cancer. Dr Muller says there is some research into how lung cancer could be hereditary based on specific genetic markers, but currently it is in the early stages, and more studies are needed to prove it definitively. Unfortunately, for those who have undergone chemo or radiation therapy, the risk of lung cancer is increased. Some chemo drugs cause scarring to form in the lung tissue or abnormalities which predispose them to lung cancer in the future.

“It isn’t all bad news, though. Leading a healthy life, getting exercise and avoiding the risks as much as possible will go a long way towards healthy lungs. And, perhaps most importantly, stop smoking as that not only damages your lungs but those of everyone around you,” says Dr Muller from Cancercare.