Question

Which of the following air pollutant reduces oxygen holding capacity of lungs?

• A. Carbon dioxide
• B. Nitrogen dioxide
• C. Sulphur dioxide
• D. Carbon monoxide

Answer 1

The correct option is D Carbon monoxide

Carbon monoxide reduces the oxygen carrying capacity of haemoglobin in our blood. Haemoglobin has higher affinity for carbon monoxide than oxygen. So, in the presence of carbon monoxide, instead of binding with oxygen, haemoglobin binds with carbon monoxide to form a stable compound carboxyhaemoglobin. Hence it reduces oxygen holding capacity of lungs.