What’s Really in a Vape and Why It Matters for Teens

21 November 2025

Posted in

Vaping has become a major temptation for teens, with sleek-looking devices and candy-like flavors. Many people, especially teens, believe it’s a harmless alternative to smoking. The truth is much more complicated.

The aerosol from a vape isn’t just water vapor. It’s a mix of chemicals that can have serious effects on the body, particularly for young people whose brains and lungs are still developing.
Knowing the facts can help you and your teen make informed decisions about your health.

In this blog, we speak to Clay Reed, M.D., a thoracic oncologist and hematologist at the INTEGRIS Health Cancer Institute, to learn more.

“Vaping delivers multiple known and probable carcinogens directly into the lungs,” Reed says. “These toxicants cause DNA damage in lung cells—the hallmark of cancer development. While the long-term data on vaping and lung cancer will take decades to mature, the biological mechanisms are concerning for increases in cancer and other health issues.”

What is in a vape?

The basics: Vaping devices, also known as e-cigarettes or vape pens, work by heating a liquid to create an aerosol that is inhaled. These devices come in many shapes and sizes, but they all contain similar internal components. Understanding what these products are made of is the first step in recognizing their potential harm.

Vaping products consist of a battery, a heating element and a place to hold the e-liquid.
The battery powers the heating element, which turns the e-liquid into an aerosol or “vapor.”
This vapor is then inhaled through a mouthpiece into the lungs.

What’s in the e-liquid inside a vape?

The details: The e-liquid or “vape juice” is the substance that gets heated into an aerosol. While flavorings make it seem appealing, the liquid contains a cocktail of chemicals that can be harmful when inhaled.

Flavorings in e-liquids create various tastes but may have unknown effects on the lungs.
Most e-liquids contain nicotine, an addictive substance that can harm brain development in younger people.
Propylene glycol and vegetable glycerin produce vapor but may cause throat irritation and respiratory issues.
E-liquids sometimes contain toxic chemicals like formaldehyde and acetaldehyde.

Flavoring is a key component used to attract users, especially younger people, with thousands of options available from fruit to candy flavors. While these flavorings are often approved for consumption, they are not meant to be inhaled into the lungs.

The chemical diacetyl, used in some flavors like buttered popcorn, is linked to a serious lung disease called bronchiolitis obliterans or “popcorn lung.”
Inhaling flavor chemicals can cause inflammation and damage to lung tissue.
The long-term effects of inhaling the specific chemical combinations in flavorings are still largely unknown.

Nicotine is a highly addictive substance found in most e-liquids, even in some products that claim to be nicotine-free. This chemical is what makes both traditional cigarettes and vaping so hard to quit.

Nicotine is particularly harmful to the developing adolescent brain, which continues to mature until age 25 or later.
It can harm the parts of the brain that control attention, learning, mood and impulse control.
Using nicotine in adolescence can increase the risk for future addiction to other drugs.

Propylene glycol and glycerin are used to create the visible aerosol or “vapor” when the e-liquid is heated. These substances are considered safe in food and cosmetics, but their effects when inhaled are not well understood.

When heated, propylene glycol and glycerin can form toxic compounds like formaldehyde and acetaldehyde.
Inhaling these substances can cause irritation to the lungs and airways.
Long-term exposure may lead to lung inflammation and other respiratory issues.

Heavy metals from the heating coil of the vaping device can leach into the e-liquid and be inhaled into the lungs. These metals can be toxic to the body.

Vape aerosol can contain heavy metals such as nickel, tin and lead.
These metals can get deep into the lungs and cause damage to lung cells.
Long-term exposure to heavy metals is linked to lung, liver, immune system and brain damage.

Other chemicals like acetaldehyde or acrolein are also present in vape aerosol and are known to cause significant health problems. These chemicals are often byproducts of the heating process.

Acrolein, a weed killer, can cause irreversible lung damage.
Acetaldehyde and formaldehyde are known carcinogens, which means they can cause cancer.
These chemicals contribute to lung irritation and can aggravate conditions like asthma.

The risks of vaping

Why it matters: The damage from vaping can be short-term or lead to chronic conditions that last a lifetime.

Vaping can exacerbate asthma symptoms, leading to increased difficulty in breathing.
Chemicals in vaping products can cause permanent scarring of the lung tissue, impairing respiratory function.
Exposure to carcinogens in vaping products significantly increases the risk of developing certain types of cancer.
Vaping has been linked to increased blood pressure and a higher risk of heart disease.
Vaping may weaken the immune system, making the body more susceptible to infections.

Asthma can be triggered or worsened by vaping. The irritants in vape aerosol can cause inflammation in the airways, making it harder to breathe.

Vaping can increase the likelihood of developing asthma in the first place.
For those who already have asthma, vaping can lead to more frequent and severe asthma attacks.
The chemicals in e-liquid can cause coughing, wheezing and shortness of breath.

Lung scarring is a severe and permanent form of lung damage that can result from vaping. Certain chemicals in e-liquids are known to cause this irreversible condition.

Diacetyl, found in some flavorings, can lead to bronchiolitis obliterans, a condition that scars the smallest airways in the lungs.
This scarring narrows the airways and makes breathing difficult.
There is no cure for this condition, which is often called “popcorn lung.”

Organ damage extends beyond the lungs. The nicotine and other toxic substances in vape aerosol can affect the heart and brain.

Nicotine raises blood pressure and heart rate, which can increase the risk of a heart attack.
In adolescents, nicotine can disrupt brain development, impacting memory and concentration.
The long-term effects of these chemicals on other organs are still being studied.

EVALI, or e-cigarette or vaping product use-associated lung injury, is a severe lung illness linked to vaping. It caused a major outbreak in 2019, leading to hospitalizations and deaths.

Symptoms of EVALI include coughing, shortness of breath, chest pain, fever and vomiting.
Vitamin E acetate, an additive in some THC-containing vapes, is strongly linked to the EVALI outbreak.
While cases have declined, EVALI remains a serious risk for anyone who vapes.

Cigarette smoking can be the next step for many young people who start with vaping. The nicotine addiction developed from vaping can lead them to try other tobacco products.

Studies show that teens who vape are more likely to start smoking cigarettes in the future.
This transition exposes them to the thousands of additional harmful chemicals found in cigarette smoke.
Vaping can act as a gateway to a lifelong addiction to tobacco.

Secondhand exposure to vape aerosol is also a concern. The vapor exhaled by a user contains nicotine and other harmful substances that people nearby can inhale.

There is no safe level of exposure to these chemicals.
Secondhand aerosol can be particularly harmful to children, pregnant women and people with respiratory conditions.
Vaping indoors exposes everyone in the room to these potentially toxic substances.

Cancer is a long-term risk associated with some of the chemicals in vape pens. The carcinogens in vape pens can damage DNA and lead to the growth of cancerous tumors.

Chemicals like formaldehyde and acetaldehyde, which can be formed when e-liquids are heated, are known to cause cancer.
While the long-term cancer risk from vaping is not yet fully known, the presence of these carcinogens is a major red flag.
The risk is likely lower than with traditional cigarettes, but it is not zero.

Teen vaping conversation tips

Key points: Talking to your teen about vaping can feel intimidating, but having an open and honest conversation is the most important step to vaping prevention for the youth. Approaching the topic with empathy and facts rather than judgment can make your teen more receptive to what you have to say.

Set the stage for a calm, uninterrupted conversation in a relaxed environment like a car ride or a walk.
Ask open-ended questions to understand their perspective, such as “What are your thoughts on vaping?” or “Do you know kids at school who vape?”
Share facts, not scare tactics, by presenting credible information about health risks from reliable sources like the CDC.
Emphasize your concern for their health and well-being, letting them know you care about their choices.
Discuss refusal skills together, brainstorming ways they can say no to peer pressure without feeling awkward.
Be a good role model. If you use tobacco products, consider quitting to show them that you really believe it’s a poor health choice.

Find a doctor at INTEGRIS Health

Next steps: Talking to teens about vaping can be hard, but if you or your teen are concerned about the effects of vaping, the dedicated health care professionals at INTEGRIS Health are here to support you. Don’t wait to take control of your health. Schedule an appointment with one of our primary care physicians today to discuss your concerns and create a plan for a healthier future.