ERS delegates have been presented with yet more evidence that it is too premature to allow e-cigarettes to be marketed as a ‘safe’ alternative to conventional cigarettes.

In one study presented at the ERS congress in Milan, researchers from Sweden asked more than 30,000 people randomly selected from the general population about their smoking habits, use of e-cigarettes and respiratory symptoms.

Around 11% of people surveyed said they only smoke conventional cigarettes, while 0.6% said they only use e-cigarettes and 1.2% said they used both.

E-cigarette use was more common among people who currently smoke conventional cigarettes (9.8%), compared to former smokers (1.1%) or non -smokers (0.6%).

The results also showed that people who use both conventional cigarettes and e-cigarettes were the most likely to experience respiratory symptoms.

Among non-smokers 26% experienced any respiratory symptoms, compared with 34% of those using only e-cigarettes, 46% of those only smoking conventional cigarettes and 56% of dual users.

The results suggested that cigarette smokers might be using e-cigarettes in public places that prohibit conventional cigarettes or they were using them to help quit smoking.

Whatever the reason, the findings do not support the common argument that e-cigarettes help smokers quit, the researchers told delegates.

“We have also found that people who use both conventional and e-cigarettes are more likely to suffer wheezing, or a long standing or productive cough.

It could be that some smokers, who are already suffering these symptoms, want to quit smoking by changing to e-cigarettes but they are not managing to stop.”

Alternatively, they said it could be that using both products causes worse respiratory effects than either alone.

“This research adds to the evidence that e-cigarettes cannot yet be marketed as a safe alternative to conventional cigarettes,” they concluded.

Respiratory irritants in e-cigarettes

Meanwhile another study from Crete found that 122 of the most commonly sold e-cigarette liquids in nine European countries contained at least one substance known to be a health risk.

Furthermore 15% of the liquids analysed containing phathlates, an ingredient well documented as being toxic to humans.

This was despite a European mandate that stated: “Except for nicotine, only ingredients are used in the nicotine containing liquid that does not pose a risk to human health in heated or unheated form”.

“The impact of these substances and their subsequent heating on human health is an area that warrants further research,” lead researcher Dr Constantine Vardas told delegates.

“In order to ensure the protection of European consumer’s health monitoring of e-cigarette additives are necessary and should be urgently addressed,” he added.