August 11, 2020


What is nicotine?

For many people, the danger of smoking is closely associated with nicotine. Some people believe that it is solely responsible for the diseases that tobacco causes, such as cardiovascular disease and lung cancer. The truth is that these people are far from knowing the true effects and other dangers of the substances in cigarettes. We take stock to better understand nicotine, its effects, its toxicity for humans and the environment.

Nicotine, origin and properties

Let us recall that it was Christopher Columbus who brought tobacco (and therefore nicotine) back to Europe in 1492 after his trip to America. Indeed, nicotine is an alkaloid naturally present in high concentration in tobacco leaves. It is also present in other plants such as tomato and eggplant. Its toxicity protects the plant from insects.

Effects of Nicotine on smokers

From cigarette smoke, nicotine passes quickly through the lungs, blood and central nervous system. This short delay between dose and effect is one of the keys to the potential for nicotine addiction. Among other things, nicotine binds to the brain, releasing adrenaline, dopamine, serotonin, beta-endorphin and vasopressin.

In the short term, nicotine has a psychoactive effect and induces an improvement in memory capacity, inhibits appetite and improves mood. But in the long term, nicotine causes concentration problems.

Nicotine and dependency

Nicotine is one of the most powerful neurotoxic poisons. However, taken in small quantities, addiction grows. In this way, nicotine is a psychoactive substance that is addictive to more than half of all smokers. Thus, tobacco addiction develops like other addictions, such as alcoholism or drug addiction.

Is nicotine dangerous?

For the human species

The nicotine molecule in the cigarette itself is harmless and not carcinogenic. In fact, at this dose, nicotine is the only non-toxic substance in cigarettes.

It’s its diffusion in the form of nicotine shots that is dangerous. Indeed, the nicotine contained in cigarettes is very quickly diffused through the arteries and causes smokers a brain shoot effect.

This provokes feelings of pleasure, thus maintaining the addiction. However, the physical dependence it causes is short-lived and does not last more than a few days.

However, abruptly stopping it can lead to signs of withdrawal: irritability, anxiety and headaches.

For other species and the environment

Nicotine (ecotoxic to cold-blooded animals such as fish) is increasingly present in the aquatic environment at significant doses. This nicotine comes from the billions of cigarette butts exposed to the rain, thrown into water and gutters.

The use of nicotine, as a pesticide, is highly regulated in Europe because of its toxicity on aquatic biodiversity. Because this molecule is highly soluble in water.

Also, a study in the Journal of hazardous material, classifies cigarette butts as "hazardous waste". One reason for this is the nicotine content of the cigarette butts.


You now know better what is nicotine and its effects on smokers. Think about the other harmful substances in tobacco. If you want to quit smoking, you can get Kwit to help you. A new feature allows you to track your nicotine consumption to understand it and decrease it step by step for a complete stop. More information about this feature here.

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