Hi LD Di!
Wow-what a bummer about the underwear. For sure they are adding something with the same type of scent in all the clothing. My daughter up in Nova Scotia frequents a chain of thrift stores called Frenchy's and she asked them about the scent even in the used clothing. They said that they fumigate all their clothing I guess to kill 'bugs'. Of course, this fumigant is scented to cover the chemical smell. So my best guess is that all imports are treated like this for the same reasons. I know that they do this to imported new cars as well. This would explain why I always smell the same sickening fragrance on all clothing that I buy in any store. I cannot wear it without washing it in fragrance free detergent first. If that didn't work I would put them in a small basin and use my ozonator to try to zap the chemical smell out of them. If you have a small ozonator maybe you can try it.