Almost nine out of 10 vape retailers have either knowingly or unwittingly been prepared to sell e-cigarettes to people who have never smoked or vaped which is in direct violation of regulations.

The Independent British Vape Trade Association (IBVTA) code of conduct says e-cigarettes are for current or former smokers and existing users of vaping devices and should never be sold to anyone who is not a current or former smoker, or a current vaper.

But an investigation by the Royal Society for Public Health (RSPH) into 100 of the UK's 1,700 specialist vape shops found that:

*Almost half of stores did not check whether new customers were current or former smokers.

*Three quarters of those that did check continued to encourage the customer to start vaping, even once they knew they were a non-smoker.

The code of conduct exists to ensure e-cigarettes are marketed and perceived as an effective aid for quitting smoking, rather than as a lifestyle product.

While the number of vapers who have never smoked is currently small, RSPH has some concerns about the potential appeal of vaping to non-smokers, fuelled by an increase in vape shops on high streets.

Although e-cigarettes are now regarded as a safer alternative for smokers, there remain uncertainties about their long term risks and the RSPH says it is concerned at non-smokers beginning to vape.

To support more responsible and targeted retailing of e-cigarettes RSPH is calling for all vape stores to:

*Screen customers for current smoking behaviour, and advise those who have never smoked or vaped against starting vaping.

*Ensure all customers who smoke are aware of their local stop smoking service.

*Adopt a 'Challenge 25' approach to ensure the legal sale age of 18 is properly enforced.

These calls appear alongside a number of other recommendations in a new RSPH policy paper on e-cigarettes, including:

*Business rates relief to be considered as a means to encourage small retailers to no longer sell tobacco products.

*An end to tobacco advertising in trade publications.

*All local stop smoking services to become e-cigarette friendly.

Shirley Cramer Chief Executive, RSPH said: "E-cigarettes are an important recent development, which are estimated to create an additional 16,000 ex-smokers in England every year.

"They are widely recognized to be far less harmful than cigarettes and we would encourage anyone struggling to quit their smoking habit to consider using e-cigarettes. It is of particular concern that only one in eight smokers who have never vaped believe e-cigarettes are a lot less harmful than smoking tobacco, and we need to do more to convince smokers that switching to e-cigarettes is a safer alternative.

"High street vape stores are the visible face of vaping in the UK, and so it is crucial that they are seen as responsible retailers of evidence-based quitting aids - rather than lifestyle products - which are targeted exclusively at smokers.

However, as our investigation shows, the majority of vape shops in the UK are not adhering to these important standards. We are keen to support the sector to strengthen their codes of best practice, and for individual retailers to sign up and ultimately adhere to them."