I'd get someone to hold the rod while i wind off about 25 ft and let the line run between my finger & thumb. If you get any whitish color residue then throw that line out. It's the plastizier comming out. Other wise go ahead & use it. Not so much cold temps, but hot temps can destroy the line. Mono will dry out.
One trick some guys use is to wind that line onto a 3rd reel and use the 3rd reel. Sometimes it works, sometimes it doesn't.
Tom B.
(LongLine)