There are two ways, both work on skin, only the second will work on clothing or other material:
There is a product called What Odor? that I'm sure will do the trick. I use it on my work boots, and it completely gets rid or the odor of cow manuer, and worse. Had me saying what odor??
yes
Check the surrounding areas and the duct itself for anything (dead animal? wet area? mold? ) that could be causing the odor.
Spray it with some What Odor? I purchased this product and it gets rid of any odor, and it does not return!!!!! Order at www.whatodor.com
Yes, It gets rid of bad body odor and stops sweating.
Get the dead animals out of your heater ducts.
Getting rid of foot odor is hard once it gets bad, but my mother used these to get rid of her foot odor: *Keep your feet clean! Cleanliness kills the bacteria that causes odor. *Keep your feet dry! Socks made of cotton are best to absorb sweat and moisture. *Stay away from garlic, onions, curries, chilis, and alcohol. These can cause foot odor, as well as bad breath.
He has to call a professional.
The best product to use for these types of odors Freshana Organic Solutions'
Animal control does.Added: . . .or the Sanitation Department - or the Highway Department - or the Department of Public Works - etc.
birds such as penguins and seagulls
You can buy leather cleaner or leather conditioner. That would probably get rid of the smell.