Introduction

The number of vape users has raised a public health concern: nicotine poisoning from e-liquid exposure. E-liquids, the flavoured solutions used in electronic cigarettes (e-cigarettes), contain concentrated nicotine, a potent neurotoxin that can cause severe harm or death if ingested or absorbed through the skin. Although vaping is considered a safer alternative to smoking by most people, recent reports have shown different results. The risks of unawarded nicotine poisoning among children and careless adults are increasing, and they are usually not noticed. This article examines the two most dangerous routes of nicotine exposure, ingestion and skin absorption, and their associated risks. By understanding how these exposures occur, recognising symptoms, and adopting preventive measures, individuals can mitigate the dangers posed by e-liquids.

What is nicotine?

Nicotine is a family of naturally occurring alkaloids found in several varieties of plants, notably tobacco, or produced synthetically. This compound is the primary addictive substance in products like cigarettes, cigars, chewing tobacco, e-cigarettes, and nicotine pouches. It acts as a stimulant and affects the brain’s reward pathways, leading to dependence.^1,2

What is nicotine poisoning?

Nicotine poisoning occurs when the body absorbs excessive amounts of nicotine that it cannot metabolise. Children and adolescents face higher risks of nicotine poisoning due to their smaller body size and developing physiology. Nicotine works primarily through the activation of nicotinic acetylcholine receptors (nAChRs). nAChRs are mainly found in the nervous system; they trigger the release of multiple neurotransmitters, including acetylcholine, dopamine, and GABA, across different brain regions.³

Commercial e-liquids have various nicotine concentrations ranging from 0 to 100 mg/mL. The majority of them fall within the 3–36 mg/mL range. These concentrations frequently exceed the European Union's regulatory limit of 20 mg/mL for nicotine-containing e-liquids. Based on human case studies, the lethal dose of nicotine is estimated to range between 50 and 60 milligrams, according to research by Lazutka et al. (1969). Also, the other study showed that the lethal nicotine dose for non-smoking adults is established at 0.8–1 mg/kg body weight. In low doses, this creates mild stimulant effects (e.g., increased alertness), but higher doses cause paralysis of muscles, including those critical for breathing.^4,5,6

Routes of exposure and associated risks

Ingestion 

The rising popularity of electronic cigarettes has introduced new public health challenges. Fruit, candy, and dessert-flavoured e-liquids may attract children and adults and lead to unfavourable accidents. A report of a fatal case involving a 24-year-old woman who intentionally consumed approximately 3000 mg of nicotine-containing e-liquid. Post-ROSC toxicological analysis of the patient revealed markedly elevated plasma nicotine and cotinine levels (>1000 ng/mL each).⁷

The study analysed 223 e-cigarette liquid exposure cases reported to poison centres across eight EU countries between 2018-2019. Researchers found nearly two-thirds (64.7%) of exposures were accidental, with all cases involving children under five being unintentional. Approximately 73.8% of cases occurred by ingestion, and over half of the cases developed symptoms like nausea, vomiting, or dizziness. While most incidents were managed at home, the findings highlight ongoing safety concerns.⁸

Skin absorption

The preliminary study investigated whether nicotine can be absorbed through skin, either directly from air or indirectly from contaminated clothing. Researchers exposed two bare-skinned participants and one clothed participant to environmental tobacco smoke containing 420 μg/m³ of nicotine for three hours while they breathed clean air through protective hoods. The bare-skinned participants absorbed approximately 570 μg of nicotine through their skin, with urinary metabolite levels similar to those seen in non-smokers exposed to secondhand smoke. The participant wearing clean clothes absorbed only about 20 μg, demonstrating clothing's protective effect. Interestingly, when the participant wore a shirt already exposed to nicotine, the absorption amount increased 4 times more than the clean one. This indicated that contaminated clothes might be related to nicotine exposure.⁹

These findings reveal that nicotine could be absorbed through skin. The children or non-smokers may be exposed to nicotine through both air contact and contaminated household fabrics without notice. Unlike inhalation, skin exposure often lacks immediate warning signs, enabling toxic doses to accumulate before symptoms emerge. This delayed onset increases the risk of severe poisoning before individuals recognise the danger.

Emergency response and first aid measures

Prompt and effective action can save a life or avoid severe adverse effects in any suspected case of nicotine poisoning. Recognising the symptoms is the first step. Nausea, vomiting, cramping in the abdomen, lightheadedness, tachycardia (rapid heartbeat), increased salivation, and sweating are common symptoms of nicotine poisoning. More serious symptoms may appear as the poisoning worsens, such as trouble breathing, muscle weakness, disorientation, convulsions, or even unconsciousness.

Seeking emergency medical attention is crucial when ingestion is suspected. Immediate decontamination is essential for skin exposure. Nicotine, particularly in liquid form, can be quickly absorbed through the skin. Wash the affected area with soap and water if e-liquid gets on the skin. Reducing the amount of nicotine absorbed as fast as possible to protect from nicotine absorption. If the exposure is severe or symptoms start to show, seek medical help as fast as possible. 

When handling e-liquids or refilling vape pens, gloves can help avoid unwanted skin contact.

It is essential to educate parents and vape users and raise awareness about nicotine exposure. Emergency numbers should be readily available in houses containing vaping products, and poison control centres should be contacted without delay.

Safe e-liquid handling and storage procedures

Cutting down on risks for unintentional exposure is the most secure way to lower the danger of nicotine poisoning from e-liquids. Safe handling and appropriate storage are important steps to prevent ingestion or skin contact, especially for children, dogs, and other susceptible people, regardless of whether you regularly vape or live in a home with e-liquids.

Safely store e-liquids

To prevent children and pets from reaching any nicotine products, it is essential to keep any type of nicotine products away from them; for example, place e-cigarettes in a locker.

A significant number of poisoning cases happen just because a bottle was left out on a counter, bedside, or table. Many e-liquids have fruit or candy flavours, which makes them easy for young children to confuse with food. Avoid carrying e-liquids loose in bags or purses where they could leak or spill, and never keep them near food or beverages.

Check seals and use child-resistant packaging

Make sure the cap is securely secured after every use, and only buy e-liquids that are packaged to keep children out. Additional dangers may arise from the use of bottles with loose closures or weak seals for some poor or fake goods. It's best to dispose of the container properly if it seems damaged or doesn't seal tightly. After handling or refilling, always wash down the bottle's outside to get rid of any residue that might be transferred by touch.

Take care, if gloves are required, wear them

Wear gloves to prevent direct skin contact when changing e-liquid containers or refilling vaping devices, particularly if the nicotine content is high. If the liquid is absorbed via the skin, even minor spills might cause symptoms like nausea or dizziness. Refills should always be done on easily cleaned surfaces.

Get rid of e-liquid correctly

E-liquid must be disposed of carefully. It can be hazardous to the environment, so never pour it down the toilet or sink.

If you are not sure how to dispose of the products, please seek advice from local disposal regulations.

Empty e-liquid bottles or used vape cartridges should be cleaned, properly sealed, and disposed of to avoid leaks or unintentional retrieval by kids or pets. Users can significantly lower the danger of unintentional nicotine poisoning in their homes by implementing these simple handling and storage procedures into everyday activities.

Conclusion

The skyrocketing number of users of vapes is an overlooked public health problem; the awareness of nicotine toxicity should not be overlooked. As this article has shown, there are distinct risks associated with both ingestion and skin absorption, which are important routes for nicotine poisoning. The nicotine content in e-cigarettes frequently surpasses legal limits. In addition, their fruity and sweet smells raise the risk of accidents for children and pets who might accidentally consume them. Furthermore, nicotine is able to penetrate skin through contaminated clothing or household fabrics directly or indirectly. The effect of nicotine is usually not easy to detect until symptoms appear. As the vaping trend continues, it is vital that users and families understand the potential dangers of nicotine exposure and take proactive steps to protect themselves and others.