I don't know why I'm bothering with this...as it's really Pariah that should be providing extensive, legitimate documentation of his arguments...but here goes. The views of the three leading psychological associations on homosexuality:

U.S.A
Canada
Britan

As to the physical dangers, I can provide a series of comparative articles that list the risks involved in vaginal sex vs. those in anal sex. If you're willing to read them, you'll note that all of the warnings/risks are identical. And despite looking, I have yet to come across a journal that ascribes any serious risk (besides STI transmission, which is common to every form of intercourse) to the practice.

If karma's a bitch, it will be my bitch!