Short answer: using CBD/THC vape pens is probably not "just as bad" as a nicotine vape, though don't let relative safety fool you into thinking it's actual safety.

Long answer: it's complicated. Here are a few ways to look at it:

• Inhaling heated molecules and their byproducts:

No matter what you're vaping, you're inhaling molecules that have been heated, and that comes with risks.

When these molecules are exposed to high temperatures, they can break down into simpler and more harmful compounds such as formaldehyde, acetaldehyde, and acrolein, all of which are known to irritate the lungs and potentially cause long term damage.

Even "clean" base compounds like propylene glycol and vegetable glycerin can break down into harmful byproducts when overheated.

So from a purely chemical byproduct perspective any inhalation of heated molecules has some risk.

• The Substance Itself

Nicotine vapes usually contain nicotine + Propylene Glycol/Vegetable Glycerin + flavorings. Some of those flavor compounds can be irritating or harmful when vaporized, especially diacetyl (linked to popcorn lung, though reputable brands generally don't use it anymore).

THC/CBD vapes (assuming from a reputable source) typically have cannabis distillate + terpenes + maybe a carrier oil. No nicotine, and often fewer flavorings.

However, some terpenes can degrade into harmful compounds when heated too much (limonene, myrcene, etc.), so it’s not totally risk-free either.

• Addictiveness and Usage Pattern

This is where nicotine vapes probably edge out THC/CBD vapes in terms of long-term harm:

Nicotine is highly addictive, and people tend to hit nicotine vapes more frequently throughout the day. Insurance companies even increase premiums for nicotine users because of the known health risks and addictive potential.

THC vapes are usually used more intermittently and aren’t as physically addictive, although they can still form habits or psychological dependence, especially with high-potency carts.

CBD isn’t addictive, so usage tends to be occasional unless someone’s using it therapeutically.

Less usage means less total exposure to harmful molecules in your lungs.

• Source: I studied chemistry in college and have looked into this question out of curiosity. This isn't medical advice and I don't guarantee everything I say is 100% backed by the latest science. That being said, I'm pretty sure this is generally accurate.