That is generally true; the nicotine in e-liquid is commonly extracted from tobacco. But at the point it is mixed into an e-liquid, assuming we're talking about

That is generally true; the nicotine in e-liquid is commonly extracted from tobacco. But at the point it is mixed into an e-liquid, assuming we're talking about a reputable organization, it is a completely pure nicotine solution. The only thing it shares with the tobacco it came from is the nicotine itself.