Air Pollution and Cancer: A Silent Crisis in India

Important Key Points for SSC, UPSC & Govt Exams

  • India’s cancer cases are projected to rise from 1.46 million (2022) to 1.57 million (2025).
  • Lung cancer cases are increasing among non-smokers.
  • Air pollution is classified as a Group 1 carcinogen by WHO.
  • India was the 5th most polluted country globally in 2024.
  • PM 2.5 levels in India exceed WHO limits.
  • Non-smokers with lung cancer often present with adenocarcinoma.
  • Common misdiagnosis as tuberculosis delays lung cancer treatment.
  • ICMR (Indian Council of Medical Research) projects cancer trends and is a key organization in the field.

Introduction

India is currently witnessing a dangerous rise in cancer cases, with air pollution being identified as a key contributing factor—particularly for lung cancer among non-smokers. According to projections by the Indian Council of Medical Research (ICMR), cancer cases in India will increase from 1.46 million in 2022 to 1.57 million by 2025.

Cancer Burden in India

Cancer has become the second leading cause of death from non-communicable diseases in the country. Alarmingly, 1 in every 9 Indians is expected to be diagnosed with cancer during their lifetime. Among all types of cancer, lung cancer is one of the most common in both males and females.

Changing Patterns in Lung Cancer

Traditionally, lung cancer was linked primarily with smoking. However, recent reports reveal that up to 30% of lung cancer patients in India are now non-smokers. In Chennai, the number of non-smoking lung cancer patients has risen from 40% to over 55% in recent years.

The type of lung cancer also varies based on smoking history:

  • Non-smokers tend to develop adenocarcinoma.
  • Smokers typically have squamous cell carcinoma.

The Role of Air Pollution

The World Health Organization (WHO) classifies air pollution as a Group 1 carcinogen, which means there is strong evidence that it causes cancer.

India’s condition is particularly alarming:

  • India ranked 5th most polluted country in the world in 2024.
  • PM 2.5 levels (fine particulate matter) are well above WHO’s recommended limits.

While a strong correlation between air pollution and lung cancer exists, experts call for further research to confirm a direct causal link.

Diagnostic and Treatment Challenges

A major barrier in tackling lung cancer is the late diagnosis. Symptoms are often vague, and tuberculosis is commonly suspected first, which delays proper treatment. As a result, many patients reach hospitals in advanced stages, when treatment options are limited.

Although India has improved its cancer diagnostic infrastructure, rural and remote areas still suffer from lack of access to timely healthcare.

The Way Forward

Experts stress the need for:

  • Extensive research into the link between pollution and cancer.
  • Policy changes and multi-sectoral efforts to reduce air pollution.
  • Monitoring cleaner regions like the Northeast India for early interventions.
  • Promoting indoor air purification and reduction of household pollutants.

Static GK Section (for MCQs)

Indian Council of Medical Research (ICMR)

  • Established: 1911 (as IRFA), renamed ICMR in 1949
  • Headquarters: New Delhi
  • Parent Organization: Ministry of Health and Family Welfare
  • Functions: Biomedical research, health statistics, disease monitoring
  • Key Projects: National Cancer Registry, COVID-19 data, NCD studies

Chennai (Reference from Study)

  • State: Tamil Nadu
  • Capital: Chennai
  • Chief Minister (2025): M. K. Stalin
  • Important Rivers: Cooum, Adyar
  • National Parks in TN: Mudumalai, Guindy, Gulf of Mannar
  • Famous Institutions: IIT Madras, ICMR-NIRT

Possible Exam-Based MCQs

Q1. According to ICMR, how many cancer cases are expected in India by 2025?
A. 1.35 million
B. 1.46 million
C. 1.57 million
D. 1.60 million
Answer: C. 1.57 million

Q2. What percentage of lung cancer cases in India now occur in non-smokers (as per latest data)?
A. 10%
B. 20%
C. 30%
D. 50%
Answer: C. 30%

Q3. Which city’s studies showed a rise in non-smoking lung cancer patients from 40% to 55%?
A. Mumbai
B. Chennai
C. Delhi
D. Kolkata
Answer: B. Chennai

Q4. Which type of lung cancer is more common in non-smokers?
A. Squamous cell carcinoma
B. Small cell carcinoma
C. Adenocarcinoma
D. Sarcoma
Answer: C. Adenocarcinoma

Q5. In 2024, what was India’s rank among the world’s most polluted countries?
A. 1st
B. 3rd
C. 5th
D. 7th
Answer: C. 5th

Q6. What is the full form of ICMR?
A. Indian Cancer Medical Research
B. Indian Council for Medical Research
C. Institute of Cancer and Medical Research
D. International Council of Medical Regulation
Answer: B. Indian Council for Medical Research