The dangerous paicle size causing pneumoconiosis varies from ?

Ans. is 'd' i.e., 1-5 m Pneumoconiosis o Pneumoconiosis is an occupational lung disease caused by the inhalation of dust. o The development of pneumoconiosis depends on - (i) The amount of dust retained in the lungs and airways. (ii) The size, shape of the paicles --> The most dangerous paicle ranges from Ito 5 m in diameter because they may reach the terminal small airway and air sacs and settle in their linings. (iii) Paicle solubility and physiochemical reactivity. (iv) Additional effects of other irritants (e.g. concomitant smoking). Impoant pneumoconiosis o Cool worker's pneumoconiosis (CWP) --> Coal dust o Silicosis (grinder's disease) --> Silica dust o Asbestosis --> Asbestos dust o Beryliosis --> Berylium dust o Siderosis --> Iron dust o Byssinosis --> Cotton dust