Science Advocacy
Science Advocacy
Welcome to “chemicals and society” a new feature at UYBFS where we highlight the current understanding of the biologic effects and safety of some of the most common chemicals in today’s society.
What is Nicotine and how are people exposed to it?
Nicotine is an alkaloid produced naturally by a number of plants in the night shade family, most notably the tobacco plant. People are mainly exposed to nicotine by smoking (cigarettes, cigars, pipes, smokeless tobacco), but also via vaping or e-cigarettes. Some people may be exposed to nicotine or related chemicals when using them as insecticides on crops.
What does Nicotine do?
Plants produce nicotine as an insecticide to keep insects from eating their leaves. Nicotine binds to nicotinic acetylcholine receptors (nAChRs) in the central nervous systems of insects, causing paralysis and death. In mammals, the nAChR receptor subtypes are different, and as a consequence, nicotine binds more weakly and stimulates the nervous system, causing the characteristic addictive “high” that people seek out by smoking.
Nicotine itself (sold as nicotine sulfate) can be used as a pesticide, though it is not currently sold in the U.S. Nicotine derivatives (known as neonicotinoids) are widely used as insecticides across the world. They have come under quite a bit of scrutiny lately because these insecticides are very good at killing bees – and could be one of the contributors to colony collapse disorder.
What are the health effects of nicotine?
OK, so we all know smoking is bad, right? But the question is how bad?
Really, really bad:
But most of the effects I mentioned above are not actually due to the nicotine itself, but the other chemicals in tobacco, and the combustion products in the smoke. People smoke for the nicotine, which is highly addictive, but the majority of the damage is done by the other chemicals that come along for the ride. However, this doesn’t mean that nicotine is blameless. Nicotine sulfate insecticide is dangerous, and there are reports of several people killing, or trying to kill others with nicotine. It’s not easy to acutely poison yourself with nicotine by smoking it, but it is (surprisingly) common for adults or children to become poisoned by eating cigarettes or drinking the concentrated nicotine solution used in vaping or e-cigarettes.
E-cigarettes are billed as a “safe” alternative to smoking because they deliver only the nicotine. However, emerging science suggests that this is untrue. First of all, the repeated exposure to high levels of nicotine may contribute to the increased risk of heart disease seen in smokers. It’s also clear that nicotine is toxic to the developing fetus. More importantly, e-cigarettes are not able to deliver pure nicotine alone – other chemicals, including formaldehyde and benzene (known carcinogens), acrolein (which causes heart disease), and lead (not good for you) are present at dangerous levels in e-cigarette vapor.
What’s the bottom line?
Nicotine is a poison produced by plants to kill bugs trying to eat their tasty, tasty leaves. As luck would have it, this poison produces an addictive high in humans that our species has been pursuing for years. This quirk of pharmacology has led the lowly tobacco plant to become one of the most dangerous things humanity has ever encountered: it has literally killed millions of people over the past 500 years. Smoking is terrible for you, and while e-cigarettes may not be as bad as cigarettes, there are still risks. Inhaling a pesticide to get high doesn’t sound like a good idea, and it isn’t. It’s best to steer clear of nicotine.
