What is meant by second hand smoking?

Define secondhand smoke: tobacco smoke that is exhaled by smokers or is given off by burning tobacco and is inhaled by persons nearby. read more

That could mean that people need to be aware not only of secondhand smoke from cigarettes and other tobacco products, but might need to worry about people taking smoke breaks outside, or even the residue from years ago. read more

Second-hand smoke: Environmental tobacco smoke that is inhaled involuntarily or passively by someone who is not smoking. Environmental tobacco smoke is generated from the sidestream (the burning end) of a cigarette, pipe or cigar or from the exhaled mainstream (the smoke puffed out by smokers) of cigarettes, pipes, and cigars. read more

Secondhand smoke exposure can be measured by testing indoor air for nicotine or other chemicals in tobacco smoke. Exposure to secondhand smoke can also be tested by measuring the level of cotinine (a by-product of the breakdown of nicotine) in a nonsmoker’s blood, saliva, or urine . read more