Lung Cancer & Air Pollution

We’ve all known for a long time that exposure to toxins harms health, but who would have imagined that the air we breathe could be a slow poison and be one of those toxins?

According to the World Health Organization (WHO), air pollution kills an estimated seven million people worldwide yearly. Air pollution is the contamination of air by substances that are harmful to humans or other living beings and damage the environment.

Breathing polluted air is known to impact almost every organ in the body. Most commonly air pollution affects the respiratory tract, it is the main pathway of exposure to air pollution and can lead to issues like asthma, bronchitis, etc. Recent studies also indicate that exposure to particulate matter (PM 2.5, PM 10) and nitrogen dioxide (NO2) are leading contributors to the rising number of health conditions like respiratory issues, cardiovascular problems, renal conditions, and even cancer. According to a recent report by ‘The Hindu’ lung cancer cases are increasing in non-smokers and air pollution is believed to be the culprit. 

An expert pulmonologist at the CK Birla Hospital, Dr. Kuldeep Kumar Grover asserts that lung infections and air quality are directly related. You run a greater risk of getting respiratory ailments the more polluted the air you breathe. Asthma, bronchitis, COPD, lung cancer, and other lung conditions are caused by high levels of pollutants, especially PM2. 5 which are small enough to penetrate deep into the lungs. Reducing exposure to air pollution is the only way to ensure your safety. Additionally, avoiding eating outside food can help minimise the risk of aerophagia (swallowing of air).

What is Lung Cancer?

The lungs are an important organ that helps us breathe. The primary role of the lungs is to absorb oxygen from the air we breathe and remove carbon dioxide. Additionally, the lungs help break down blood clots, regulate blood pressure, maintain the body’s acid level balance, support the sense of smell, etc. The main organ of the respiratory system is located in the chest cavity.

A number of illnesses can interfere with the lung’s normal function resulting in symptoms like shortness of breath, sleeplessness, irregular breathing, loss of consciousness, restlessness, and other related issues. Lung disorders are primarily caused by infections, environmental factors, or abnormal cell growth. One such potentially severe life-threatening condition is lung cancer.

According to a recent report, lung cancer is a common cancer and a leading cause of cancer-related death in India. A leading contributing factor to this rising number is the usage of tobacco smoking. The spread of cancer is further categorized into stages, including

• Stage 0: Cancer is on the top lining of the lung.
• Stage I: Cancer is small and confined to its origin (not outside the lung)
• Stage II: Cancer has grown but localized to nearby tissues (spread to lymph nodes)
• Stage III: Cancer has spread to nearby lymph nodes or tissues
• Stage IV: Cancer has spread to distant organs or parts of the body & to the other lung.

Types of Lung Cancer

Lung cancer usually starts in the airways or small air sacs. Various types of cancer affect the lungs, however, there are two main types of lung cancer. 

• Non-Small Cell Lung Cancer (NSCLC): This is the most common type of lung cancer accounting for almost 80% of cases. 
  
• Small Cell Lung Cancer (NSCLC): This type of lung cancer is less common and is considered a more aggressive type known for rapid growth and early spread. 

Air Pollution: A Growing Concern

The last several decades have seen a major global concern over air pollution. A wide range of diseases can result from both short-term and long-term exposure to pollutants and the majority of people live in areas where pollution levels can rise. One of the main causes of cancer according to the International Agency for Research on Cancer (IARC) is air pollution, specifically PM 2.5. Additionally, chronic exposure can impact all of the body’s organs complicating and aggravating pre-existing medical conditions. Air pollution can cause a variety of health problems: 

• Respiratory Problems

  Pollutants present in the air we breathe can increase the risk of respiratory infections like pneumonia.
  

• Heart Diseases

  Pollutants like PM2.5 and nitrogen dioxide can enter the bloodstream and increase the risk of heart attacks, high blood pressure, etc.

• Lung Cancer

  Pollutants can penetrate deep into the lungs, causing inflammation, DNA damage, and oxidative stress leading to cancer.
  

• Chronic Obstructive Pulmonary Disease

  Exposure to harmful pollutants irritates and inflames the airways leading to damage of lung tissues & reducing lung function and other related conditions.

• Weakening of Immunity

  Long-term exposure to pollutants can result in weakening of the immune response making individuals more susceptible to infections.
  

• Other Cancer Risks

  Long-term exposure to substances like benzene, polycyclic aromatic hydrocarbons, and PM2.5 increases the risk of developing bladder cancer, breast cancer, Leukemia, and other types of cancer.

The Link Between Air Pollution and Lung Cancer

Despite the fact that tobacco products and cigarette packets are marked as they cause cancer a sizable section of the populace still consumes them. Tobacco remains the leading cause of the growing number of lung cancer cases. Air pollution has also been identified as an emerging factor. Even though there are fewer cases connected to air pollution the tendency to overlook such issues in their early stages persists. It’s crucial to address this perspective and act proactively.

Exposure to pollutants like PM2.5, nitrogen dioxide, polycyclic aromatic hydrocarbons, etc penetrate deep into the lungs causing,

• Inflammation
• DNA Damage
• Oxidative Stress

Leading to mutation and cancer cell growth. Additionally, prolonged exposure to such pollutants disrupts the cell repair mechanism and weakens the immune system, increasing the risk of cancer over time. Other lung issues caused by air pollution include,

• Asthma: Breathing difficulties are caused by pollutants such as particulate matter and ozone which aggravate and cause asthma symptoms.
• Reduced Lung Function: Long-term exposure to harmful pollutants can reduce lung capacity in adults.
•  Respiratory Infection: Air pollution is known to weaken the immune system making the lungs more prone to infections like pneumonia and bronchitis.

Symptoms Indicating that Poor Air Quality is Harming Your Lungs

• Breathing Issues

  Difficulty breathing or feeling out of breath with routine activities is a clear symptom of lung damage due to air pollution.

• Chest Congestion

  Individuals experience congestion or discomfort in the chest region due to exposure to harmful pollutants.

• Increased Mucus Production

  A common sign indicating poor air quality is impacting the lungs is excessive phlegm or mucus production as the lungs try to clear irritants & pollutants.

• Irritated Throat

  Dryness or soreness may be felt in the pharynx due to long-term or even short-term exposure to pollutants.

• Wheezing

  Individuals may experience whistling or squeaky sounds while breathing indicating airway constriction.

• Frequent Infections

  Respiratory Infections like recurring colds, bronchitis, or pneumonia may be experienced by individuals indicating lung damage

Vulnerable Populations More Prone to Poor Air Quality Affecting Their Lungs

• Children

  During the developing phase or growing phase the lungs are more sensitive to pollutants. Additionally, children are more active and breathe faster, increasing the level of exposure.

• Elderly

  With age lung function naturally weakens and the immunity level declines making the elderly population more prone to such lung conditions.

• Pregnant Women

  Exposure to pollutants affects maternal lung health and can increase the risk of adverse pregnancy outcomes, like preterm birth, low birth weight, etc.

• Individuals with Pre-existing Respiratory Conditions

  Individuals already diagnosed with asthma, COPD, or bronchitis are at higher risk of exacerbations.

• Individuals with Heart Conditions

  Air pollution is known to worsen cardiovascular health, leading to individuals with various heart conditions at high risk.

• Smokers or Former Smokers

  Smoking affects normal lung function, leaving smokers and former smokers with damaged lungs more vulnerable to health risks due to exposure to pollutants.

• People Living in Urban Areas

  People living in urban areas are more exposed to pollutants from traffic emissions, industrial pollutants, etc increasing the risk.

Risk Factors

The risk of developing lung-related conditions can be raised by exposure to harmful substances and certain environmental factors. Key risk factors include:

• Smoking 
• Air Pollution (PM 2.5, toxic gases)
• Weakened Immune System (HIV, Chemotherapy)
• Geographical Location (Urban, industrialized areas)
• Age (Young children & elderly adults)
• Pre-existing Conditions (Asthma, allergies, etc)

Preventive Measures

FAQs

Is lung cancer curable?

Lung cancer is not usually curable, however, some cases may be cured if diagnosed before they spread. The outlook depends on the stage of the cancer, age, and overall health. 

What are the symptoms of lung cancer?

Some of the common symptoms of lung cancer include coughing, shortness of breath, wheezing, chest pain, blood clots, etc.

How is lung cancer detected?

Lung cancer is detected through imaging tests like chest x-ray, CT scan, MRI, PET scan and tissue samples like sputum test, core biopsy, etc.

Can lung cancer be detected by x-ray?

Yes, lung cancer can be detected by chest x-rays.

What causes lung cancer?

Lung cancer may be caused by several factors including, smoking, exposure to certain chemicals, exposure to pollutants like PM 2.5, etc.

Can lung cancer be cured at stage 4?

No, stage 4 lung cancer is not curable, but it can be treated, the treatment goal focuses on relieving symptoms, improving quality of life, and prolonging life.

Is lung cancer genetic?

Yes, lung cancer can be genetic.