Sweat, polyester clothing, and corrosion

So, before traveling abroad for 1 month, I had two polyester garments that had sweat on them from exercise. Wasn’t able to get them washed before leaving.
I ponder chemistry questions a lot, so, how corrosive is the salt and other stuff in sweat, on fabrics like polyester?

Pretty much not at all. Polyester isn’t quite inert, but it’s pretty resistant to everyday things, especially at room temperature.

http://www.engineeringtoolbox.com/chemical-resistance-polyester-d_784.html

I’d think the biggest issue might be washing whatever it is out of the polyester after it’s been festering in your bag for a while.