The measure of air pollution that has the greatest impact on human respiratory health due to its ability to penetrate deep into alveoli is:
- A PM2.5 (particulate matter ≤2.5 μm) ✓
- B PM10 (particulate matter ≤10 μm)
- C Carbon monoxide
- D Sulfur dioxide
Correct answer: A. PM2.5 (particulate matter ≤2.5 μm)
Explanation
PM2.5 (fine particulate matter ≤2.5 μm aerodynamic diameter) is the most health-damaging air pollutant because it penetrates past the upper airways and tracheobronchial tree to reach the alveoli, entering systemic circulation. It is associated with cardiopulmonary disease, lung cancer, and premature death. PM10 is deposited in the upper airways and does not reach alveoli as effectively.
Reference: Park's Textbook of Preventive and Social Medicine, 27th ed.
High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP
Written and medically reviewed by the StethoPrep medical team.