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also used to make things like anti-freeze, pain solvent, and artificial smoke in fog machines Carcinogens chemicals known to cause cancer, including acetaldehyde and formaldehyde Nicotine a highly addictive substance that negatively affects adolescent brain development Acrolein a herbicide primarily used to kill weeks, can cause irreversible lung damage Diacetyl a chemical linked to a lung disease called bronchiolitis obliterans aka popcorn lung Diethylene glycol a toxic chemical used in antifreeze that is linked to lung disease High levels of nicotine can be absorbed through spills on the skin or by children swallowing the liquid Heavy metals such as nickel, tin, lead Cadmium a toxic metal found in traditional cigarettes that causes breathing problems and disease Benzene a volatile organic compound (VOC) found in car exhaust Ultrafine particles that can be inhaled deep into the lungs Due to effective targeted marketing, non-smoking teens are drawn to e-cigarettes because of appealing, candy-like, sweet, menthol, mint, or fruit flavors

But nicotine is not, in fact, the most harmful ingredient in a cigarette, though it might be the most addictive
According to a 2015 NCBI Report, people who smoked more than 20 cigarettes per day had a 19% reduction in sperm quantity