What’s the Connection Between Air Pollution and Blood Cancer?

Every year, around 1.24 million new cases of blood cancer are diagnosed across the globe, accounting for nearly 6% of all new cancer cases. In India, the situation is even more alarming, with 80,000 to 100,000 new cases reported annually. More than 70,000 people are affected every year, making up about 8% of all cancer cases in the country. These numbers not just statistics because they represent real lives affected by a deadly disease whose causes are often difficult to trace. Recent studies have increasingly pointed toward environmental factors, especially air pollution and blood cancer, as a growing health concern. Polluted air filled with harmful particles and chemicals can enter the bloodstream, disturb normal cellular functions, and raise the risk of developing blood cancer.

But here’s what makes this even more concerning: a growing body of research suggests that one of the hidden triggers behind these cases could be something we encounter every day air pollution. While most people associate air pollution with asthma, heart disease, and lung problems, few realize it can also play a major role in the development of blood cancer. Toxic particles and harmful chemicals inhaled from polluted air can enter the bloodstream, disrupt cellular processes, and trigger mutations that lead to cancer.

So, how exactly does air pollution increase the risk of blood cancer? What are the mechanisms behind this deadly connection? And who is most vulnerable?

In this blog, we will explore what blood cancer is, how it affects your body. And how air pollution is turning into one of the major environmental factors contributing to this silent killer. We will also look at data, studies, and practical steps you can take to protect yourself and your loved ones from this growing threat. 

What Is Blood Cancer and How Does It Affect Health?

Blood cancer, also known as hematologic cancer or haematological malignancy, is a group of cancers. It begin in the bone marrow or the cells of the immune system. It is one of the deadliest health conditions that can affect the chances of survival if not diagnosed and treated early. Blood cancer affects the production and function of blood cells. It disrupts the body’s ability to fight infections, transport oxygen, and form clots.

There are three main types of blood cancer:

1. Leukaemia – A cancer of the blood-forming tissues, including bone marrow, causing excessive production of abnormal white blood cells.
2. Lymphoma – A cancer that affects the lymphatic system, which is responsible for immune responses.
3. Myeloma – A cancer that develops in plasma cells, which are a type of white blood cell.

How Does Air Pollution Cause Blood Cancer?

When pollutants such as particulate matter (PM2.5 and PM10), benzene, polycyclic aromatic hydrocarbons (PAHs), and heavy metals like arsenic and lead are inhaled. They are absorbed into the lungs and then pass into the bloodstream. These toxic substances trigger oxidative stress, DNA damage, and inflammatory responses. All of which contribute to abnormal cell growth and mutations in blood cells.

Mechanisms Behind Blood Cancer Caused by Air Pollution

1. DNA Damage
   Pollutants like benzene are known to cause direct damage to the DNA of blood-forming cells, leading to mutations that can initiate cancerous growth.
2. Immune System Suppression
   Exposure to air pollutants weakens the immune system, reducing the body’s ability to destroy abnormal cells before they multiply.
3. Chronic Inflammation
   Constant exposure to pollutants causes chronic inflammation in the lungs and blood vessels, which can create a favourable environment for cancer cells to grow.
4. Oxidative Stress
   Fine particulate matter increases the production of free radicals, damaging blood cells and promoting tumour development.

Who Is at Higher Risk of Developing Blood Cancer Due to Air Pollution?

The risk of blood cancer from air pollution is higher in:

• People living in highly polluted cities, such as Delhi NCR or Bangalore, have a higher chance of developing blood cancer issues.
• Children and the elderly, whose immune systems are weaker, are at higher risk of blood cancer. 
• Individuals with pre-existing health conditions, such as respiratory or cardiovascular diseases
• Smokers, who are already exposed to harmful chemicals
• People with occupational exposure, like industrial workers or traffic police

Data From Research

A comprehensive review published by the World Health Organisation and other peer-reviewed journals suggests that long-term exposure to PM2.5 and benzene increases the risk of blood cancer by 15% to 40% depending on the level and duration of exposure. Studies conducted in urban centres show that populations exposed to pollution levels above 100 µg/m3 of PM2.5 are at significant risk.

Cities With High Air Pollution and Blood Cancer Cases

Delhi – A Case Study

As of the latest available data, India registers approximately over 100,000 new cases of blood cancer annually, accounting for about 8% of all new cancer cases in the country. This includes various hematologic malignancies such as leukaemia, lymphoma, and myeloma. 

Notably, leukaemia is the most prevalent form of blood cancer in India, with an estimated 9,883 new cases annually. Following closely are Non-Hodgkin lymphoma with 39,736 cases and Hodgkin lymphoma with 9,611 cases each year.

Delhi, one of the most polluted cities in the world, often records air quality index (AQI) levels above 500 during winter months, which is classified as ‘severe’ pollution. During these periods, the concentration of PM2.5 rises to dangerously high levels. As often exceeds 300 µg/m3, far above the safe limit of 60 µg/m3.

A study conducted in Delhi observed an increase in blood cancer diagnoses during high pollution months. As with an estimated 15% more cases reported annually compared to lower pollution periods. Hospitals in the capital region report hundreds of blood cancer-related consultations every month. And oncologists have noted the correlation between air pollution and rising cancer trends.

Other cities like Mumbai, Kolkata, and Bengaluru also face increasing pollution levels and a growing burden of blood cancer cases, though the highest risks remain in northern cities with heavy industrial and vehicular emissions.

Practical Ways to Reduce Air Pollution and Lower Blood Cancer Risk

Although air pollution cannot be eliminated overnight, individuals, communities, and governments can take actionable steps to reduce exposure and minimise the risk of blood cancer.

At the Individual Level:

• Use air purifiers at home to reduce indoor air contaminants.
• Avoid outdoor activities during peak pollution hours, especially in winter.
• Wear N95 or equivalent masks when commuting or working in polluted environments.
• Maintain a healthy diet rich in antioxidants, such as fruits and vegetables, to counteract oxidative stress.
• Regular health checkups, including blood tests, to detect early signs of abnormalities.

At the Community and Government Level:

• Strengthen vehicular emission norms and promote electric vehicles.
• Increase green spaces like parks and tree plantations in urban areas.
• Regulate industrial emissions and ensure strict compliance with environmental laws.
• Promote clean energy solutions, such as solar and wind power.
• Encourage public transport use, carpooling, and cycling to reduce traffic-related pollution.

Conclusion

Blood cancer is a severe health condition that not only affects individual lives but also places a significant burden on healthcare systems worldwide. With an estimated 1.24 million new cases globally each year, and 80,000 to 100,000 cases in India alone. It is critical to understand the environmental factors contributing to its rise. Air pollution, long known for causing respiratory and heart diseases, is now being recognised as a major risk factor for blood cancer as well.

By raising awareness, following preventive measures, and supporting clean air initiatives, we can protect ourselves and our communities from the silent but deadly impact of air pollution. Reducing pollution is not just about clean air—it is about safeguarding life itself.