Scott Freda on Instagram: "Why Marijuana Smoke Harms Lungs 1. Harmful Chemicals: Cannabis smoke contains tar, carcinogens, and other toxins similar to tobacco smoke, causing inflammation and cell damage in airways. 2. Inhalation Method: Holding marijuana smoke in the lungs deposits more harmful chemicals, increasing damage. 3. Chronic Bronchitis: Regular users often report symptoms like coughing, phlegm, and wheezing, hallmarks of chronic bronchitis, which is part of COPD. COPD Risk & Evidence I