With caffeine, this varies widely from person to person, depending on age, sex, general health, weight, metabolic rate, and current medications
More than 16 million Americans have one or more diseases caused by smoking, responsible for $170 billion in direct medical costs that CDC officials say would be saved if we could prevent youth from starting to smoke and help every person who smokes to quit. Secondhand smoke is believed to contribute to more than 40,000 deaths among nonsmoking adults and 400 infant deaths each year, per the CDC
10.1038/nature09146 57
E-cigarette use is now an epidemic among adolescents
All the corrective statements that the tobacco companies have to make are available here
Other workers who may be exposed to benzene include coke oven workers in the steel industry, printers, rubber workers, shoe makers, laboratory technicians, firefighters, and gas station employees