Cooling flavours show potential warning flag, though more research is needed

New research has found that substances added to a wide variety of vaping flavours to create a cooling sensation may be harmful but researchers suggest more work must be done to formally confirm the theory.

Two substances known as WS-3 (derived from menthol) and WS-23 are added to produce a cooling sensation in the mouth and throat. They can be found in many minty and mint-like flavoured e-liquids but also further afield in flavours such as strawberry-banana.