Second hand e cigarette vapour increases risk of poor respiratory health, study finds Nursing in Practice Federal Investigators Think Black Market Vaping Products, Not Legal E Cigarettes, Are to Blame for Respiratory Illnesses Chronic Inhalation of E cigarette Vapor Negatively Affects Lungs Respiratory Therapy Citric Acid Produces Respiratory Sensitizers in E Cigarette Vapor Long Term Use of E cigarettes Linked to Respiratory Disease Allergy & Asthma Network Addressing the challenges of E cigarette safety profiling by assessment of pulmonary toxicological response in bronchial and alveolar mucosa models Scientific Reports