E-cigarettes are growing in popularity despite limited research on their short- and long-term effects. With an extensive list of appealing flavors, these devices may attract new “never smokers” who assume that e-cigarettes are less harmful than traditional tobacco products.
Carcinogens
Inhaled vapor from electronic cigarettes can contain:
- Nicotine.
- Ultrafine particles that can be inhaled deep into the lungs.
- Flavorings such as diacetyl are chemicals linked to serious lung disease.
- Volatile organic compounds, including benzene.
- Heavy metals like nickel, tin, and lead.
Researchers are just beginning to understand the health impact of these chemicals when they are heated and converted into an aerosol and inhaled by users and non-users who are exposed secondhand. However, many are still asking, “Can electronic cigarettes cause cancer?”
The strongest evidence of the potential association between e-cigarette use and cancer will come from methodologically rigorous epidemiological studies with human cancer as the outcome. However, it is important to consider that many e-cigarette users will also be current or former combustible tobacco cigarette smokers, and this will be a challenging confounder to account for in observational studies.
Nicotine
Nicotine is a powerful, addictive chemical that can cause numerous health issues. It promotes pathologic angiogenesis and retinal neovascularization, contributing to age-related macular degeneration. It also inhibits insulin secretion, leading to a rise in blood sugar and glucose levels. It increases the risk of type 1 diabetes mellitus. Additionally, it stimulates gluconeogenesis and accelerates cataract formation.
It takes just 10 seconds for nicotine to reach the brain when it is inhaled from e-cigarettes, which can lead to addiction. Youth are particularly vulnerable to nicotine addiction. Because their brains are still growing until age 25, they can become addicted more easily. In addition, they build synapses faster than adults. This makes them more susceptible to the rewards of smoking and other addictive drugs like cocaine.
Several studies have compared EC use with traditional smoking. However, these studies have some significant limitations. For example, many studies have not separated smokers from non-smokers or accounted for the amount of TC smoke they inhale while using ECs.
Flavoring
The liquid nicotine and flavoring in e-cigarettes (and other electronic nicotine delivery systems, or ENDS) is turned into a breathable aerosol by a heating element. E-cigarettes are also known as vape pens or sticks, mods, and personal vaporizers (PVs).
While it is unclear if the aerosol produced by e-cigarettes is harmful to people who use them (active vaping) or those who breathe in secondhand vapor, we do know that the liquid can contain:
- Harmful chemicals, including nicotine.
- Ultrafine particles that penetrate deep into the lungs.
- Chemical flavorings such as diacetyl have been linked to severe lung disease.
In one study, researchers found that two commonly used flavored e-cigarette chemicals damaged the epithelial cells that line human lungs. They altered gene expression and impeded the functioning of cilia, which are responsible for sweeping dust, bacteria, and mucus out of the airways.
In addition, some workers in flavored cigarette and popcorn manufacturing plants have been diagnosed with early pulmonary disease due to exposure to diacetyl, which is released by the heating of butter in these facilities. The lung disease in these workers is characterized by fixed airway obstruction on spirometry, a test that measures how well the lungs work.
Rechargeable Batteries
A battery-powered device that heats liquid nicotine and other additives to produce an aerosol. The fluid can contain nicotine concentrations ranging from 14.8-87.2 mg/mL, but only 10% of the total amount of nicotine reaches the systemic circulation.
Studies of EC health effects have included experimental, quasi-experimental, observational (including cohort and cross-sectional), case-control, and qualitative studies. Results have varied widely, with some reviews dividing outcomes into acute and longer-term effects and not specifying the timeframe for each. In contrast, others reported improved lung function and respiratory symptoms for former smokers who switched to ECs. However, studies of e-cigarette use have often been confounded by the fact that participants who switch to e-cigarettes may continue to smoke conventional cigarettes. Additionally, many studies have been subject to COI, with authors reporting financial links to e-cigarette manufacturers.
According to the National Academies of Sciences, Engineering, and Medicine, report, long-term e-cigarette use poses significant risks, including an increased risk of heart disease from inhaling secondhand vapor, which can include cancer-causing chemicals like acetaldehyde, acrolein, and formaldehyde, as well as irritants such as phenols and particulates.
Children
A new study by the Royal College of Physicians found that children as young as 13 and 14 are using e-cigarettes and tobacco products. In a survey of over 1,000 children, they were asked to self-report how often they saw cigarette and vaping products in shops and supermarkets, including if they noticed these products on display.
E-cigarettes resemble traditional cigarettes, cigars, pipes, or other common gadgets such as pens, flashlights, USB flash drives, gaming controllers, fidget spinners, and car key fobs. Some popular e-cigarettes, such as the JUUL, contain as much nicotine as a pack of 20 regular cigarettes.
These devices may also be marketed to children with cartoon characters and other attractive packaging or shaped to appeal to youth. A considerable amount of calls to poison centers involve kids incidentally exposed to e-cigarette liquids through ingestion, inhalation, or dermal contact. These exposures can cause tachycardia, dizziness, and even seizures. They can also be fatal if they inhale an e-liquid containing nicotine. This is especially dangerous if these refills are not sold in child-safe containers.