Your lungs are the gateway between chemical and biological pollutants and your bloodstream. Diet, lifestyle, genetics etc all affect your health and resilience to immunological invasions. Even with eating fresh organic food, getting plenty of exercise and maintaining a low stress work behavior, you are still at risk of attack from airborne pollutants.

like a bronchial tube into the earth, now clogged with 25Mpa concrete and Y12 deformed bar.