When the device is activated, the element becomes hot and vaporizes the e-liquid in the wick
Emerging evidence has shown e-cigarette use can lead to serious complications, including respiratory illness and death
Dr James MacCabe, from the Institute of Psychiatry, Psychology and Neuroscience at King's, said: "It's very difficult to establish causation [with this style of study], what we're hoping that this does is really open our eyes to the possibility that tobacco could be a causative agent in psychosis, and we hope this will then lead to other research and clinical trials that would help to provide firmer evidence." Clearly most smokers do not develop schizophrenia, but the researchers believe it is increasing the risk
However, other studies may use ultrasound, sample liquid near the lung or require minor incisions to collect larger tissue samples
Depending on the type, the nicotine content of a single cigarette can vary