Yes
The harm of grapefruit electronic cigarette is that formaldehyde itself is a carcinogen, and new research shows that the formaldehyde of electronic cigarette appears in a new form, semi-acetal.
This form of aldehydes can enter the lungs deeper than gas, and long-term damage needs to be studied. At present, there are many flavors of e-cigarettes, and different flavors contain different flavors. Whether these smells can be safely inhaled into the lungs after heating is also a problem.