They all use activated carbon as the key filtering material, but the shape, size, and way you use them can be very different
Triggers may include watching TV, talking on the phone, relaxing after a meal or sex, getting in or out of your car, coming out of the subway, drinking coffee or alcohol, and many others
Dame Helena Shovelton, chief executive of the British Lung Foundation, said: "It is alarming that, while new research continues to reveal the multiple health consequences of smoking cannabis, there is still a dangerous lack of public awareness of quite how harmful this drug can be
10.1038/s41392-021-00831-w 57
Closeup shot of an open pack of cigarettes Captions are provided by our contributors