Sen. Chuck Schumer issued a warning about them. Videos about them are each racking up hundreds of thousands of views on TikTok. What are these Zyn pouches that experts are concerned about young people getting addicted to?

Zyn is a nicotine pouch meant to be placed in the mouth between the upper lip and gum. It comes in several flavors, including citrus, coffee, cinnamon and several mint varieties. The products are produced and marketed by Swedish Match, a Stockholm-based tobacco company owned by leading cigarette manufacturer Philip Morris International.

They've been rising in popularity as of late: The brand shipped about 350 million Zyn cans last year, a 62% spike compared to 2022, Philip Morris announced in February.

"Zyn certainly seems attractive," Vaughan W. Rees, director of the Center for Global Tobacco Control at the Harvard T.H. Chan School of Public Health, tells USA TODAY. He notes that young people may be increasingly attracted to products like Zyn because they don't include all the same dangers as smoking — but that doesn't mean there are no dangers to using them.

"Nicotine products should only be used by legal-age adults, which means those 21-plus," a spokesperson for Philip Morris International told USA TODAY. "Swedish Match, which makes ZYN, has robust marketing practices in place to help ensure access only to those 21-plus. That includes not using social media influencers. Swedish Match data shows the vast majority are previous consumers of traditional oral, vaping, and cigarette products with others coming from other nicotine product categories."

Though the company says it doesn't market to younger consumers, some experts worry that as the products gain notoriety, they may be falling into the wrong hands anyway.

What does it mean for a nicotine product to be seen as "safer" than smoking? Here's what experts want you to know.

Is Zyn a nicotine or tobacco?

Zyn is a non-tobacco nicotine product.

As a nicotine product, "Zyn presents significantly lower health risks than smoking, because it does not contain cancer-causing chemicals and other toxic substances found in cigarette smoke," Rees says. "So Zyn may offer adult smokers who have not been able to quit smoking a way to reduce their exposure to the toxic chemicals that cause disease, including cancer."

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Are nicotine pouches cancerous?

Zyn pouches are promoted as products that can help adult smokers addicted to nicotine "lower their exposure to toxic chemicals," Rees notes. "Zyn has very low toxicity compared with smoking, so even without long-term studies we know that the long-term disease risk is likely to be lower than combusted cigarette products.

The product may be safer than tobacco, but that still doesn't mean it's good for you — especially if you don't already smoke or vape.

"Although it does not cause cancer, nicotine causes dependence and may increase the risk of cardiovascular disease in people who do not already use nicotine products," he says. And it's not yet known if it can help smokers stop smoking completely.

"We still need to understand ways that people will use Zyn in the longer term, including whether Zyn encourages young people to start using nicotine products who would not otherwise have done so," Rees adds.

Are Zyns bad for you? 

Some questions about the product's safety and efficacy are still up in the air, experts say, because Zyn has not yet been officially authorized by the U.S. Food and Drug Administration. Philip Morris International says an application for authorization to market the product in the U.S. has been pending since 2020, but the FDA has allowed the non-tobacco nicotine product to remain on the market in the meantime.

In addition to confirming whether Zyn can help adult smokers, Rees says the FDA needs to also consider whether the product is being marketed in ways that attract attention of some young people who don't already smoke.

"Zyn has a high potential to cause nicotine dependence, which creates other long term problems," Rees says. "Quitting can be extremely difficult. Zyn may be helpful to adult smokers who need help to quit smoking, but teens and young adults who do not smoke or vape should avoid this product."

The smoking aesthetic is back in style.Shouldn't people know better by now?