Comparison of the chemical composition of aerosols from heated tobacco products, electronic cigarettes and tobacco cigarettes and their toxic impacts on the human bronchial epithelial BEAS 2B cells ScienceDirect Before you take another puff, know what's inside. E cigarettes contain thousands of toxic chemicals. Ready to quit smoking? Text READY to 34191 Is vaping a safe alternative to smoking? A1AD Support High concentrations of flavor chemicals are present in electronic cigarette refill fluids Scientific Reports E Cigarettes and Vaping OHSU Chemicals in e cigarettes mix together to form new, unexpectedly toxic compounds EurekAlert!