Question

In Delhi, screens are put up across the city showing PM 2.5 levels as being dangerous. Why are these particles dangerous to our body?

• A. PM 2.5 particles are large enough to block the nose.
• B. PM 2.5 particles are so small that they are not trapped in the nose and will enter the lungs.
• C. PM 2.5 particles are small enough to cause infection.
• D. None of the Above.

Answer 1

The correct option is B

PM 2.5 particles are so small that they are not trapped in the nose and will enter the lungs.

PM 2.5 particles are extremely small particles. These particles are smaller than the hair present in our noses. Thus, these particles are not trapped in the nose and freely enter the lungs. Here, some of these particles block and kill the cells in the lungs which perform the gas exchange. Some are also absorbed into the blood stream and can cause cancer.