no more dangerous than Liverpool or London, you can be a victim of crime anywhere really or ripped off by some back street trader. Do a bit of port research on the Internet. I had a so called police officer try and fine me once in peurto RICO for simply carrying a glass bottle of pop in public and a side street jeweller get stroppy in at martin once because I decided not to buy. However the only port I have ever really felt uncomfortable in is montego bay Jamaica.
Why do you ask have you seen or heard about security /safety issues?