Lung cancer, once primarily associated with smoking, has become an increasingly concerning diagnosis for individuals who have never smoked. As alarming as it is, this shift is contributing to the rise of lung cancer as the fifth leading cause of cancer-related deaths worldwide. This rising concern is notably compounded by the significant environmental risk factor – air pollution.
In countries like India, where air quality often dips to hazardous levels, the increasing levels of pollution are raising alarms. Air quality has become a primary concern for public health, and its association with lung cancer cases is undeniable. The Air Quality Index (AQI), which measures the concentration of pollutants in the air, is one of the tools used to assess the severity of air pollution. India, unfortunately, ranks among the most polluted countries globally, and major cities suffer from dangerously high AQI levels.
Recent research published on World Cancer Day 2025 in The Lancet Respiratory Medicine journal highlights air pollution as a growing factor in lung cancer cases, even among non-smokers. This shift from smoking-related to environmental pollution-related lung cancer has prompted serious concerns about public health, with a particular emphasis on how poor air quality impacts the lungs.
A Global Health Crisis: Lung Cancer and Air Pollution
Lung cancer remains the deadliest cancer worldwide, with over 2.5 million new cases reported in 2022 alone. According to the International Agency for Research on Cancer (IARC), the growing trend of lung cancer cases among people who have never smoked is alarming. Air pollution is becoming a significant risk factor in the development of lung cancer, which has been linked particularly to adenocarcinoma, the most common subtype of lung cancer.
Adenocarcinoma was once primarily found in smokers, but studies have shown it is now the predominant form of lung cancer, affecting both men and women equally, regardless of their smoking history. The IARC study revealed that in 2022, nearly 200,000 cases of adenocarcinoma were linked to air pollution exposure.
The findings are backed by the World Health Organization (WHO), which reported that lung cancer in never-smokers is on the rise globally. The main contributors to this shift are pollutants such as fine particulate matter (PM2.5), nitrogen dioxide (NO2), and ozone (O3), which are prevalent in urban areas and industrial hubs. These pollutants can penetrate deep into the lungs and contribute to the development of cancerous cells over time.
The Science Behind Air Pollution and Lung Cancer
The connection between air pollution and lung cancer is not immediately obvious to many people, but the science is clear. Pollutants like PM2.5 are tiny particles that are small enough to reach the deepest parts of the lungs. These particles can contain harmful chemicals, including benzene, formaldehyde, and other carcinogenic compounds, that gradually damage lung tissue. Over time, this damage can lead to mutations in the DNA of lung cells, promoting the development of cancerous growths.
Lung cancer, particularly adenocarcinoma, often presents itself at advanced stages, making it difficult to treat. It is also more aggressive and harder to diagnose early compared to other subtypes, leading to higher mortality rates. As air pollution continues to increase, the rate of lung cancer diagnosis among non-smokers is expected to rise unless substantial efforts are made to curb pollution levels.
Air Pollution in India: The Deadly Convergence of Poor Air Quality and Rising Cancer Rates
India’s air quality is among the worst globally, with major cities like Delhi, Mumbai, and Kolkata frequently experiencing hazardous AQI levels. According to the State of Global Air report, air pollution in India has become one of the leading causes of death and disease, with an estimated 1.7 million deaths attributed to it annually.
The country’s rapid urbanization and industrialization have led to increased emissions of harmful pollutants. Stubble burning in rural areas, vehicular emissions, industrial waste, and construction activities all contribute significantly to poor air quality, particularly in the winter months. The impact on health is severe, as citizens breathe in toxic air day after day, putting them at risk for chronic respiratory diseases, cardiovascular issues, and cancer.
As urban populations continue to grow and air quality continues to deteriorate, lung cancer cases in never-smokers will likely become more widespread. In fact, many non-smokers in India, particularly those in cities with high levels of pollution, are now being diagnosed with lung cancer, reflecting a concerning shift in the global burden of the disease.
Protecting Yourself: 3 Essential Steps for Lung Cancer Patients Amid Air Pollution
Given the increased risk of lung cancer due to air pollution, it is vital for people, especially those with a family history of the disease or existing lung conditions, to take proactive steps to reduce their exposure to pollutants. Dr. Ravikumar Wategaonkar, a renowned consultant oncologist at Onco Life Cancer Center in Satara and Pune, offers some crucial tips for managing lung health in the face of rising pollution levels.
1. Minimize Exposure During High-Pollution Hours
One of the most effective ways to protect your lungs from the harmful effects of air pollution is to minimize exposure during peak pollution times. The highest concentrations of pollutants typically occur early in the morning and late in the evening. During these hours, it is advisable to stay indoors, especially for those with a history of lung disease or cancer. Engaging in indoor activities like reading, watching TV, or practicing relaxation techniques can help keep you occupied while avoiding harmful pollutants.
For those who must go outside, Dr. Wategaonkar recommends wearing a high-quality mask that can filter out fine particulate matter, such as N95 masks. These masks are designed to prevent pollutants from entering the lungs and can provide some level of protection when walking through areas with high levels of pollution.
2. Ensure Good Indoor Air Quality
Air pollution doesn’t just affect us when we are outdoors – it can also have a significant impact inside our homes. It is crucial to maintain good indoor air quality to minimize the risk of exposure. Dr. Wategaonkar suggests using air purifiers with HEPA filters to remove harmful particles from the air inside your home. These filters are particularly effective at removing small particles like PM2.5, which are linked to cancer development.
Additionally, it is important to regularly maintain heating, ventilation, and air conditioning (HVAC) systems to ensure they are not circulating polluted air inside. Keeping windows closed during periods of high pollution can also prevent pollutants from entering the home.
3. Adopt a Healthy Lifestyle
While reducing exposure to air pollution is crucial, maintaining a healthy lifestyle is equally important. Eating a balanced diet rich in antioxidants, vitamins, and minerals can help strengthen the immune system and enhance lung health. Foods such as fruits, vegetables, whole grains, and lean proteins can support the body in fighting off environmental stressors.
Staying physically active is another key factor in maintaining lung health. Regular exercise strengthens the respiratory system and improves lung capacity. For those with pre-existing lung conditions or a history of lung cancer, low-impact activities such as walking, swimming, or yoga can help maintain physical health without overtaxing the lungs.
The Urgent Need for Air Quality Improvement
As lung cancer cases continue to rise, particularly among non-smokers exposed to high levels of air pollution, it is crucial that both individuals and governments take immediate action. Personal preventive measures, such as minimizing exposure during high-pollution times, ensuring indoor air quality, and adopting a healthy lifestyle, can significantly reduce the risks associated with poor air quality.
However, addressing the root cause of the problem – air pollution – requires a collective effort. Governments must implement stricter regulations on emissions, promote clean energy alternatives, and invest in solutions to improve air quality. At the same time, individuals must be proactive in their efforts to reduce their exposure to environmental pollutants.
By taking these steps, we can mitigate the rise in lung cancer cases and work towards a healthier future, free from the devastating impact of poor air quality. The battle against air pollution and lung cancer is not just one of personal health; it is a public health crisis that requires urgent attention from all sectors of society.