HOUSTON — The growing health crisis linked to vaping has been grabbing headlines in recent days, and nicotine has already been proven to be bad for brain development in teens.

But do e-cigarettes have more nicotine than a pack of cigarettes?

It’s an issue one viewer wanted KHOU 11 to verify, writing, “When you buy vape oil, you can purchase extremely high levels of nicotine! MUCH higher than what comes in a cigarette!”

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To get answers, KHOU 11 consulted Pushan Jani, MD, a pulmonologist with UTHealth/Memorial Hermann-TMC who is affiliated with UT Physicians; Dr. Amy Arrington, a pediatrician with Baylor College of Medicine and Texas Children’s Hospital; and the American Cancer Society’s website.

Dr. Jani said one vape pod can contain more nicotine than a pack of cigarettes. However, he said it varies with each product, adding the nicotine level that ends up in someone’s body depends on how often someone vapes and how deeply they inhale.

The American Cancer Society said JUUL, a popular brand with young people, has “a significantly higher amount of nicotine per puff than some other types of e-cigarettes and cigarettes.”

Dr. Arrington said the 5 percent nicotine pods sold by JUUL contain about 59 mg/ml of nicotine, or equal to a pack of cigarettes. She said other e-cig brands contain far less nicotine, between 6 mg/ml up to 30 mg/ml.

She agreed with Dr. Jani that some e-cig pods contain more nicotine than a pack of cigarettes while others contain less. Dr. Arrington said because the e-cig industry is unregulated, the amount of nicotine advertised on labels may not be the actual amount.

KHOU can verify e-cigarettes cartridges and pods sometimes do have more nicotine than a pack of cigarettes, but others have less, and some labels may not be accurate. There are also other factors that influence how much nicotine ends up in a user’s body.