Question

If natural materials are pollutants, why do we not perceive their adverse effects during their use? When such materials are referred as pollutants?

Answer 1

we don't perceive their adverse effects because we have a good immunity and also a good measure are taken before using such materials for eg using mask
such matter are referred to as pollutants when they contaminate anything and we cannot take any safety measures and now we become sick

Answer 2

Natural pollutants are active only for a short duration. Due to natural reasons their activity is limited, and they are lost after specific time. their sources are not continuous and their spread too is not regular as in case of man-made pollutants which are emitted steadily. Thus, we can avoid these substances. We also use them in limited quantity. Therefore, the natural substances, though may be polluting in nature, we are unable to pursue its toxicity. However, if we use them in abundance and create an imbalance, then its effect can be experienced as a great hazard.