Eighty-eight percent of homemade pornography, including videos and still images, finds its way onto porn sites, often without the owners' knowledge, a new study concluded.

The study analyzed more than 12,000 sexually explicit images uploaded by young people and found that the great majority of images had been stolen and published to what Britain's Internet Watch Foundation (IWF), which published the study, calls "parasite" websites.

These para-sites, exclusively devoted to hosting sexual images featuring young subjects, allegedly obtain their material from anywhere they can get it: lost or stolen cellphones, hacked private accounts on Photobucket, Flickr, or Facebook, or from chat sites and Tumblr, a blogging platform notorious for the amount of explicit self-published content by high school and college-age students.

In 2011, the now-defunct IsAnyoneUp.com published tens of thousands of stolen Facebook photos submitted by jaded ex-lovers or angry friends.

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"We need young people to realize that once an image or a video has gone online, they may never be able to remove it entirely," Susie Hargreaves, CEO of the Internet Watch Foundation, told the Guardian newspaper in London. "Once an image has been copied on to a parasite website, it will no longer suffice to simply remove the image from the online account."

David Wright, director of the UK Safer Internet Center, agreed with the study and reiterated a warning to youngsters not to send sexually explicit messages via their phones, either.

"Much of the advice for children and young people is, quite rightly, to not 'sext,'" he said.

In its report, the IWF features quotes meant to serve as a warning to others to not even make explicit photos. "One explicit image I took when I was young ... is coming up on the first page of [unnamed search engine]," one quote read.

"Every time I begin to feel good and confident about myself ... I just remember these pictures and what I did," another quote read.

The people who gave the quotes may be heartened, however, to learn that they're not alone. With camera phones and the ability to posting power in the palm of our hands now, self-made sex photos are easier to make and share than ever before. They can bet they're not alone.

This story was provided by TechNewsDaily, sister site to Live Science.