'That' Shelter Smell

I am fostering a feral mama and her 4 newborn kittens.

I have them in a cat carrier, which is inside a large veri-kennel.  The system works pretty good, it's just that the *smell* chokes the back of my throat like a vice grip.

If it does that to me, I can just imagine how the kitties feel about it.

Does anyone know any safe tricks to remove 'that' shelter smell from plastic carriers?

Kennel sol or suave shampoo if your talking about washing the kennels(or both a wash then a soak in kennel sol)

There are others on the market too.  Really depends on how much time you have to clean the kennels/if you have a back up.  I know what works for boy cats pee....and worse.

Thank-you.  I did look up the Kennel Sol website, looks like they have a very good product.

Only issue is it can be hard to find-but my local vet uses it and may be able to buy it from them.  Anything thats smelly I use a bigger container or a trash bag. 

Also when its cold putting things outside helps as long as its not cold enough to crack and no animals outside(I have a garage roof I can reach from houses window that nothing bothers.