Used high‑puff disposable vapes have more harmful chemicals ^{CEFR B2}

Disposable vape devices designed to deliver thousands of puffs are often used for days or weeks before disposal. Researchers collected popular high‑puff disposable devices from users and from discarded products in Southern California and compared the leftover liquid with fresh, unused versions of the same brands and flavors. The work, published in ACS Omega, focused on aldehydes, a class of chemicals that form when solvents and flavor chemicals break down as e‑liquid is aerosolized and heated.

The team measured several toxic aldehydes and found significant increases in methylglyoxal (MGO), glyoxal (GO), and formaldehyde after use. Esther Omaiye, a postdoctoral scholar at the University of California, Riverside and the paper’s first author, said formaldehyde is a recognized carcinogen and that MGO and GO reached milligrams‑per‑milliliter concentrations in some vaped fluids. When tested on human lung cells, these aldehydes caused measurable damage.

The researchers exposed lung cells to MGO and acetaldehyde and found that MGO caused significant cell damage, disrupted normal cell structure, interfered with energy production, and increased oxidative stress. The study reported that MGO was 10 to 100 times more toxic than acetaldehyde. Prue Talbot, a professor at UCR, said the remaining fluid in a heavily used device has a very different and measurably more toxic chemical profile than fresh e‑liquid. Chemical levels varied across brands, and extended use of high‑puff disposable vapes may lead to greater accumulation of harmful byproducts.

The authors call for more attention from regulators and scientists and advise vapers to exercise caution as devices near the end of their life. Additional contributors came from UCR and Portland State University. The work was supported by grants from the National Institutes of Health, the Food and Drug Administration Center for Tobacco Products, and California’s Tobacco‑Related Disease Research Program.