Cleaning Odor Off Binoculars?

My dad died in 2013 so my mom and I have been getting rid of his stuff little by little. He did not like to throw anything out! A week or so ago I found binoculars that he had that I would like to keep. They are in good condition and are good quality. The only problem is they have a weird odor to them. I think because he hadn't touched them in over 20 years. Does anyone know how to get rid of the smell? I tried to leave them near a open window hoping the air would help. It has only helped a small bit though.