The spreadsheets contain addresses linked to dozens of government and armed services personnel, including members of the British Army.
In addition, the hackers have revealed email addresses, usernames, dates of birth, postal codes and unique internet addresses of users' computers.
Channel 4 News has been investigating the cyber underworld, discovering which websites have been hacked and exposing the trade in personal information of millions of people through so-called "dark web" sites.
The investigation led to a secretive forum in which a hacker nicknamed ROR[RG] posted the details of users of Adult Friend Finder.
"The site seemed OK, but when I got into it I realised it wasn't really for me, I was looking for something longer term. You couldn't get into the site without handing over information.
"I deleted my account, so I thought the information had gone.
These sites are meant to be secure." Within hours of the data being leaked, hackers on the forum said they intended to hit victims with spam emails, and Mr Harper has been targeted with virused emails since his information was made public.Online crime experts believe the after the initial spam email campaign, hackers will now begin trawling through the data for potential blackmail targets.The site boasts 63 million users worldwide and claims more than 7 million British members.It bills itself as a "thriving sex community", and as a result users often share sensitive sexual information when they sign up.The information of 3.9m Adult Friend Finder members has been leaked, including those who told the site to delete their accounts.Shaun Harper is one of those whose details have been published.