How air pollution causes cancer

Outdoor air pollution causes roughly one in 10 cases of lung cancer. Though our respiratory system is fairly resilient and ups its defence mechanisms, a prolonged exposure to elevated particle pollution impacts lung functionality in even apparently healthy people.
And since we cannot avoid particle pollution exposure, taking simple steps to reduce exposure or neutralise it will reduce the severity of lung and systemic adverse health effects in both healthy and more sensitive people.
Studies have shown a significant association between exposure to particle pollution and health risks, including premature death. Health effects may include cardiovascular effects such as cardiac arrhythmias and heart attacks and respiratory effects such as asthma attacks and bronchitis.
“The size of particles is directly linked to their potential for causing health problems. Fine particles (PM2.5) pose the greatest health risk as they can get deep into the lungs and even into the bloodstream. There are a few different ways that particles in air pollution could damage DNA in cells and cause lung cancer. For example, tiny particles may build up in the lungs and change how cells replicate. This could lead to DNA damage, mutations and altered gene expression. Such changes then trigger the lung cells to grow uncontrollably,” says Dr M S Kanwar, Senior Consultant, Department of Pulmonology, Critical Care and Sleep Medicine, Indraprastha Apollo Hospitals, Delhi.Best of Express PremiumPremiumPremiumPremiumPremium
It must be recalled that the International Agency for Research on Cancer (IARC) had conducted an evaluation on the carcinogenicity of outdoor air pollution, including particle pollution, and concluded that both are Group I agents (carcinogenic to humans). It had factored in all routes of exposure and included an evaluation of individual components of particle pollution. Several studies since then have established the link between particulate matter and increased incidence of lung cancer.
“But if you are living in a city like Delhi, you can mitigate risks changing your lifestyle and behaviour. And while one cannot avoid the outdoors, one can purify the air indoors. If you are sensitive to pollution and have heart, lung issues, then internalise mask-wearing as a routine,” says Dr Kanwar.
Most experts suggest measures like staying away from wood and coal fire, reducing smoking and minimising your exposure checking real time air quality before stepping out. Make sure the indoor air is filtered through cross-ventilation or purifiers and test your home for radon levels. Invest in HEPA filters for home devices.