High-puff vapes may become more toxic with use

A new study finds that heavily used high-puff electronic cigarettes may contain higher levels of harmful chemicals than fresh e-cigarettes, raising concerns about potential health risks for users.

E-cigarettes, also called ECs or vapes, are sold with an advertised puff count—roughly how many inhalations the device is designed to deliver before it is depleted. A high-puff EC is one rated fo...