Arthritis because it is exactly caused by the air pollutants rather it’s caused by bones and nerves it occurs when the hard, slippery tissue that covers the ends of the bones where they form a joint to break down
The respiratory system is our breathing, ie "trachea, Lungs, etc." arthritis is the inflammation of someone or somethings joints. air pollution through our respiratory system wouldn't be a factor here.
It's true cause a child has an developing immune system whereas adults have that already developed so the children under development are more likely to have those problems.