MARKETING of e-cigarettes in Scottish shops has been linked with a rise in youngsters trying vaping for themselves.

The number of stores with purpose built displays for e-cigarettes more than doubled in a year - with more than a third locating the stands near items which interest the young, according to a study by Stirling University.

And those who had noticed the promotional material were more likely to have tried vaping, the research added.

The study of almost 4,000 people aged 11 to 18, found those who recalled seeing e-cigarette displays in small shops were twice as likely to have used one.

It is the first time links between the retail environment and young people's use of e-cigarettes have been studied in this fashion.

Professor Sally Haw, chair in Public and Population Health at Stirling University, said: "What we have to do is balance promoting e-cigarettes as a potential way to reduce the harms of smoking, at the same time as protecting children from being initiated into e-cigarette use."

E-cigarettes, or electronic cigarettes, are battery-powered devices that convert liquid nicotine into a vapour for the user to inhale. They avoid smoke - the biggest danger associated with tobacco. However, as they are relatively new the consequences of long term use are not well known.

Prof Haw said the product had become much more visible on the high street since 2013. The study's audit of almost 100 shops found those with special e-cigarette displays rose from 20 per cent in 2013 to 49 per cent in 2014. Almost half, she said, had positioned them near products such as sweets and icy drinks which interest the young.

As well as being promoted as a quit aid, she said, e-cigarettes are being promoted as a "lifestyle choice" which "makes them attractive to the younger end of the market."

The survey of 11 to 18-year-olds, conducted during 2015, found more than 75 per cent were aware of them, 20 per cent had tried them and eight per cent intended to try one in the next six months.

Those who remembered displays in shops and supermarkets were more likely to have experimented with e-cigarettes. Intention to try one was also significantly more common among those who recalled the stands, according to researchers who have published their findings in the journal BMC Public Health.

Prof Haw said: "The majority of those who said that they had tried were smokers and we found that reassuring. Nevertheless, there were a small proportion of people who had never tried tobacco who had experimented with e-cigarettes."

Fellow public health researcher Dr Catherine Best, added: “It is currently unclear whether young people who plan to try e-cigarettes do so because they notice e-cigarettes at point of sale or whether they notice e-cigarettes because they intend to try them in the future. Until this association is established, we need to consider how to balance promoting the benefits of e-cigarettes for adult smokers who want to quit with the need to discourage children from experimenting with these products.”

A bill has gone through the Scottish Parliament bringing in an age restriction for e-cigarette purchases of 18 but it does not ban in-store marketing.

The study, funded by the National Institute for Health Research (NIHR), is a six year collaborative project between the universities of Stirling, St. Andrews and Edinburgh and ScotCen Social Research and aims to assess how Scotland's ban on the display of tobacco products at checkouts has affected the attitudes and habits of teenagers.

In total 3,808 students from four high schools in different parts of Scotland were involved in the 2015 survey.

Professor Haw added: “The Health (Tobacco, Nicotine etc. and Care) (Scotland) Bill completed its passage through the Scottish Parliament in early March and makes e-cigarettes an age restricted product, available only to individuals 18 years of age or older.

“However, the Bill as passed does not ban point of sale marketing. Given that this study established a link between the retail environment and young people’s use of and intention to try e-cigarettes, we need to have a careful and considered debate about the role of POS marketing in the promotion of e-cigarettes.”