All cigarettes now sold in the united states must come with a warning from the surgeon general, as shown here. explain how science contributed to this policy decision by the u. s. government.

Cigarettes have warnings on them because they were found out to be dangerous. Health affects were shown and it was dangerous enough for their to be a warning. Since smoking can lead to cancer and birth defects, if a person was unaware of these consequences, they could get very sick. Once it was found out that cigarettes caused these, tests had been done to see what other health affects were caused. Science started the warning by showing the harmful consequences of smoking.

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