What's the story behind the slogan that smoking is harmful to health?

An old woman, whose husband got lung cancer because of long-term smoking, finally left her forever. Because her husband died of lung cancer caused by long-term smoking, grandma wanted to alert the world, so she ran around for seven years and finally got these six words on the cigarette case.

Extended data:

Tobacco leaves contain toxic nicotine, also called nicotine. 1 g nicotine can poison 300 rabbits or 500 mice. If people are injected with 50 milligrams of nicotine, they will die.

Smoking is the most harmful to the respiratory tract, and it is easy to cause laryngitis, bronchitis, emphysema and other diseases. When smoking, smoke enters from the mouth, passes through the throat, trachea and bronchus, and enters the blood.

Smoking can make men lose Y chromosome and increase the risk of cancer.

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