Electronic Cigarettes

What is an electronic cigarette?

Electronic cigarettes (e-cigarettes) are relatively new products that have been marketed by tobacco companies as a safer alternative to smoking traditional tobacco cigarettes. E-cigarettes are battery-powered devices used to deliver nicotine and other chemicals; they do not contain tobacco or require combustion. E-cigarettes have a battery-operated heat source that converts liquid nicotine and flavorings into a vapor that users inhale. There is still uncertainty about the long-term risks of using e-cigarettes; however, research has substantiated that e-cigarettes pose a health risk to users. 

Anatomy of an E-cigarette

E-cigarettes have three integrated components:

  • Battery: serves as a power source, various sizes and capacities
  • Atomizer: heats and vaporizes the solution
  • Cartomizer: holds flavored nicotine (e-liquid)

When the product is activated, the atomizer and cartomizer heat the e-liquid to produce an aerosol that the user inhales. 

Three Main Ingredients in E-cigarettes

E-cigarettes are designed to simulate smoking tobacco cigarettes. The aerosol produced from e-cigarettes is from a solution that contains the main ingredients of e-cigarettes: nicotine, propylene glycol and flavorings. 


  • Nicotine is derived from tobacco and has psychoactive and physiological effects. It is a potent poison when mishandled, ingested or absorbed through the skin.
  • Nicotine is an addictive substance and its levels of addictiveness vary depending on mode of delivery. It affects the cardiovascular and central nervous systems, causing blood vessels to constrict and raising pulse and blood pressure.

Propylene Glycol

  • Propylene glycol is a colorless liquid frequently added to food, such as ice cream and soft drinks, as well as cosmetics and personal hygiene products, including deodorant, shampoo and baby wipes, to keep products moist.
  • The Federal Drug Administration (FDA) considers propylene glycol “generally safe,” but only when it is consumed at appropriate levels.


  • Many e-cigarette flavors are used in foods where they are recognized as safe for ingestion (not inhalation).
  • Flavorings are sold in various fruit and candy flavors. Tobacco companies advertise e-cigarette flavorings with friendly names, like Cherry Crush and Chocolate Treat, to appeal to youth.


E-liquids or e-juices are flavored liquids heated and inhaled by the user. To create an e-liquid, nicotine is extracted from tobacco and mixed with propylene glycol and other chemicals.

  • E-liquids usually contain nicotine, propylene glycol, glycerin, flavoring agents and other toxic chemicals; they are sold in a wide variety of flavors with different levels of nicotine.
  • Even nicotine-free e-liquids have been found to contain trace amounts of nicotine and substances that are harmful to lungs.
  • The flavors in e-liquids are recognized as safe for ingestion, but not inhalation, and since the FDA does not regulate them, there are no limitations as to what can go in them.

E-cigarette Vapor

Unlike tobacco cigarettes, e-cigarette users do not inhale tobacco smoke; instead, users inhale a vapor that the e-cigarette produces from heated liquid nicotine.

  • E-cigarette vapor is not water vapor.
  • A new study found that e-cigarette vapor contains toxins and carcinogens, including formaldehyde at levels up to 15 times higher than tobacco cigarettes.
  • E-cigarette vapor can make bacterial infections resistant to antibiotics.
  • It is impossible to know exactly what secondhand vapor contains.

Health Risks of E-Cigarettes

Since e-cigarettes have been on the market for only 10 years, their long-term effects are unclear, but current research suggests there are some adverse effects.

  • Nicotine is toxic in its concentrated liquid form and highly addictive even in small doses.
  • Poisonings can occur when the liquid nicotine is absorbed through the skin or eyes. Nicotine overdoses can occur because users are not aware of how much nicotine they are inhaling. 
  • Some common side effects of e-cigarettes are vomiting, nausea and eye irritation.
  • An incurable disease known as “popcorn lung” is linked to a chemical called diacetyl, which has been found in e-cigarette flavorings. The condition causes scarring in lung air sacs that leads to excessive coughing and shortness of breath.
  • Lithium batteries power e-cigarettes, and if the battery is not properly charged, it can overheat and explode causing severe injuries to the user.
  • E-cigarettes and e-liquids have been found to contain particles, whiskers, pellets of tin and other metals, which can end up in the user’s lungs.
  • E-cigarette emissions contain volatile organic compounds and ultrafine particles that can travel deep into the lungs where they get trapped and can cause tissue inflammation.
  • E-cigarettes are not emission-free and their pollutants can be a health concern for users and people who are exposed to secondhand vapor.

Are e-cigarettes a safer alternative to tobacco cigarettes?

E-cigarettes are perceived to be less harmful than traditional tobacco cigarettes due to their lack of tobacco; some claim they can help reduce tobacco cravings/withdrawal. However, there is no scientific evidence that suggests e-cigarettes help smokers successfully quit smoking tobacco cigarettes. While e-cigarettes have been marketed as a smoking cessation tool, they are not FDA approved. Once FDA approved, manufacturers would have to ensure that the product is effective and the benefits outweigh any known associated risks. More research is needed to further determine whether and how e-cigarettes can be an effective cigarette cessation aid.

Prevention and Treatment of Nicotine Usage

Consider refraining from using e-cigarettes. People who have never smoked a tobacco cigarette are more likely to start after they have smoked an e-cigarette.

  • UC Davis students can visit the Student Health and Counseling Services’ Alcohol, Tobacco and Other Drugs Intervention Service website or call (530) 752-6334 for one-on-one assistance and information about free tobacco cessation services, including a four-week supply of nicotine replacement products. 
  • If you are ready to quit smoking tobacco cigarettes or end a nicotine addition, consider using FDA-approved nicotine replacement therapy products, such as skin patches, gum and lozenges. 
  • Free “quit kits” are available to students at the Student Health and Wellness Center.
  • Download the This is Quitting app, customized for UC Davis students.


Smoke and Tobacco Free Campus

For a healthier community and cleaner environment, UC Davis is a smoke and tobacco free campus.  Learn more about Breathe Free