Here in Cambodia I can not leave an inner tube out in the roofed over work area I have because enough sunlight comes in that I have had a tube rot in a week. If they are still in the wrapper or inside a tire/wheel they will be ok but not exposed to the humidity and sunlight.
__________________
72 Geoffery Butler, 72 Gugificatizion Witcomb, 72 Raleigh Gran Sport SS, 74 Raleigh GrandPrix dingle speed, 74 Raleigh international, 81 Centurion Pro-Tour, 85 Gazelle Primeur, 29rBMX, Surley Steamroller 650b