It is permitted to say a Davar Shebikedushah in the presence of a perspiration smell, unless it is a very disturbing smell to people. For example, if a Kohen removed his shoes to duchen and left them near a person who is still in middle of davening, that person can continue davening unless the smell is very disturbing. However, if the shoes were left near the chazzan, then even though the smell is disturbing, he may continue davening because of k’vod habriyos (that it would be embarrassing to the Kohen if he stopped).