A very wonderful and need of the day question.. thanks for asking.. Actually you can not really completely clean your lungs.. only you can keep the pollutants stress at a lower level.. you can do some yoga exercises in clean air. You can use air purifier in your working environment if affording.. you can use tablet mucomix 600 mg twice a day to reduce this stress elements.. you can best clean lungs by just avoiding further exposure.. if no further exposure is there, your body itself can clean your lungs to some extent..