Used high‑puff disposable vapes have more harmful chemicals ^{CEFR B1}

Scientists collected popular disposable vape 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 study, published in ACS Omega, examined aldehydes, a class of chemicals that form when e‑liquid is heated to make vapor.

The team measured several toxic aldehydes and found that methylglyoxal (MGO), glyoxal (GO), and formaldehyde rose significantly after the devices were used. Esther Omaiye, a postdoctoral scholar at the University of California, Riverside, noted that formaldehyde is a recognized carcinogen and that some vaped fluids reached milligrams‑per‑milliliter concentrations.

To test health effects, researchers exposed human lung cells to MGO and acetaldehyde. MGO caused marked cell damage, disrupted cell structure, interfered with energy production, and increased oxidative stress. The study reported that MGO was 10 to 100 times more toxic than acetaldehyde. The authors say chemical levels varied by brand and that extended use of high‑puff devices may increase harmful byproducts. They call for more attention from regulators and caution for vapers.