The word detrimental, I trust you are aware, means injurious, harmful, damaging, noisome, and so forth. In none of its denotations, it could be used for lethal, something that, perhaps, you are trying to imply.

What I am trying to say is that the incidence of HIV, gay bowel syndrome, hep-A, and excuse my language, anal cuts among other problems would have been far less had their been no homosexuality. That is what I mean by detrimental.