What are some risks associated with occupational exposure to antimicrobials?

It depends: You asked a really broad question. In general, the risk of any exposure depends on the type of exposure (contact, breathing, etc) and the duration of the exposure. If your exposure is simply using an antimicrobial handwash on a regular basis then your risk is very minimal.

Not aware: of any risks and exactly what type of exposure are you referring to?

Odd question : Every antimicrobial I have ever dealt with was packaged in a self contained unit. Those that require mixing would not expose the person unless they were not following proper aseptic technique. If some spilled on them the skin barrier would prevent any absorption. I really don't see any issue at all.