US Edition YouTube, the video-sharing website, is under attack from MPs for failing to prevent images of sex and violence being posted freely on the internet.
The Culture and Media Committee of the House of Commons is publishing a report saying it is "unimpressed" with YouTube's systems for policing the millions of video clips it posts online.
The site does not vet videos before the go online, instead relying on users to report "inappropriate" content, with staff removing those that they judge to be unsuitable.
The firm says that 10 hours of video are posted online every minute, making it simply impractical to vet all of those films in advance.
John Whittingdale, the committee chairman, dismissed that argument and insisted that the firm and others that host "user-generated content" should do more to filter submissions.
"Proactive review of content should be standard practice for sites hosting user-generated content," the committee says.
The MPs say the internet has a "dark side", where hardcore pornography and videos of fights, bullying and even rape can be found, as well as websites promoting eating disorder, self-harm and suicide.
The committee wants to see the creation of an industry self-regulation body to agree and police minimum standards for protection of internet users from potentially harmful content.
But it stops short of calling for statutory regulation, arguing that its effectiveness would be limited as so many sites are based overseas.
The MPs also revealed that paedophiles are using virtual worlds like Second Life to simulate sex with children, MPs have revealed.
The committee heard evidence from Jim Gamble, head of the police Child Exploitation and Online Protection centre that monitors the internet.
Mr Whittingdale, the committee chairman said: "We did find that paedophiles are going on second life and meeting and simulating sex with children.
"It was the view of Jim Gamble that someone who gets pleasure from simulated sex in second life is someone who is likely to engage child sex in real life."
The Ministry of Justice has said it is considering new laws covering the activities of people in virtual worlds.
Mr Whittingdale said that legislating for "virtual" abuse was difficult because it is an act without an obvious victim.
But he added: "There is an argument that people who are using virtual worlds for this kind of activity are dangerous."
YouTube is owned by Google, the internet search engine. The company said its current systems provide adequate curbs on inappropriate content.
In a statement, Google said: "For YouTube we have strict rules on what's allowed, and a system that enables anyone who sees inappropriate content to report it to our 24/7 review team and have it dealt with promptly.
"We educate our community on the rules and include a direct link from every YouTube page to make this process as easy as possible for our users.
Given the volume of content uploaded on our site, we think this is by far the most effective way to make sure that the tiny minority of videos that break the rules come down quickly."