TEENAGERS are putting their futures at risk by "sexting" and posting indecent images of themselves online, says Plymouth expert Professor Andy Phippen.

And young people engaging in "websex" should realise that their most private moments could end up being seen by anyone, he said.

More than 40 per cent of 14 to 16-year-olds have friends who have texted indecent images of themselves, Prof Phippen, one of the country's leading experts in children and the Internet, told his inaugural lecture at Plymouth University.

And 15 per cent of teenagers had told his researchers that they saw nothing wrong with sending a naked image on a mobile device.

A significant number of young people – some as young as 11 – were forming relationships online that then spill offline, in many cases for casual sex, he said.

For most people in their older teens and early twenties, technology of some description plays an important part in explicit aspects of their relationships, he said.

"Technology seems to be shifting what is acceptable in society and also how young people start doing this sort of thing – in some cases as young as 11."

A study by Prof Phippen revealed that 80 per cent of those aged 16-24 had used a smartphone or the web for sexual purposes.

One in ten 16-24-year-olds who responded to the survey had made contact with people online and then subsequently met them in the "physical" world to have casual sex.

And 60 per cent of those aged 16-24 felt that online activities formed a regular part of interaction in a relationship.

But Prof Phippen warned that careless use of phones and the Internet could come back to haunt young people.

"I wouldn't like my daughter of 15 to post images like some of those we have seen on a public forum. Once it's out of your control you don't know what happens to it. There are some websites where people post explicit images of their exes, for example."

Employers were increasingly looking at social networking websites to learn more about job applicants.

"After I gave a talk at Devonport High School for Boys many of the sixth-formers went away and tightened up their Facebook profiles," he said.

"Sexting is one of the main problems that schools have to deal with. There have been a couple of cases in the United States where teachers have been dismissed for confiscating pupils' phones, so I advise them to call in their local PCSO."

Schools were good at technical issues like filtering Internet access within the school walls, and having effective policies for pupils going online, he said.

But schools in the South West, along with many others across the country, were weaker when providing effective support and training, in particular for staff. They needed to learn to be "Internet savvy".

"Certain young people have very distorted viewed of what 'normal' sexual activity is," he said.

He urged parents to take responsibility for their children.

"What's wrong with using communal family spaces to go online? Why do your children need to go to their bedrooms to go online?"

He said the arrival of 4G technology would make the problem even harder to control by allowing streaming video on mobile phones.

Prof Phippen has been conducting work into how children and young people engage with technology and use it in their social lives since 2005, and has worked with companies such as British Telecom, Orange and Facebook.

His academic study titled "The Use of Technology in Relationships" was conducted in association with the UK Safer Internet Centre.

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