Are there any risks involved for a 33year old adult if he wants to be circumcised?

"Wanting" isn't risk: Circumcision is unnecessary if normal, adequate hygiene is done. Boys are born complete, finished, and just fine (except for the few unlucky ones with birth defects). Circumcisions are for religious and cultural reasons, but the surgery does permanently change the penis, so one should think about it and talk about it before doing anything. Wanting isn't risky, but doing surgery has some risk.