Email [email protected] or flag one of their posts noting the profile.
The Overlord wrote up an answer also that more describes the why:
Our general approach has been to take a hands-off approach to the user page -- it's for you to place whatever you want there, within reason. Obviously racism, hate speech, any sort of overt evil will not be tolerated. But there is more flexibility in the grey areas on the user page, because it's about the user, not us.
We have much stricter rules about what content can appear on our question pages, we expect a modicum of professionalism throughout -- but the user page belongs to the user. Whatever content is there in the "about me" section reflects directly on that user, not us. And I don't think any reasonable website visitor would expect otherwise.
(In other words, if someone has an intentionally stupid Teh Facebooks profile, that doesn't make Teh Facebooks look stupid to most folks.)
In this case, its clearly racist. You can take either approach noted in the first quote. Both mods and SE employees have the power to change about me's.