Vaping, Venous Valves, and Vein Disease Can I be Affected by Secondhand Vape Smoke? While early research suggests it may not be as dangerous as secondhand smoking, it's still not harmless, experts say. https: www.wate.com news does vaping cause secondhand smoke doctors explain the side effects ?utm_medium=social&utm_source Vaping is less harmful than smoking, experts say. Why don't smokers know this? Scienceline