Possible Clues:

• First in election, Prime Minister assuming he has long time -- but such things are transitory!
• Items not meant to be kept
• FM broadcast with time for transitory things
• They yield short-term interest, showing edge in record time
• Paper collectibles
• Short-lived items
• They won't last long: record time on edge
• Oriental drug in exotic hamper only lasts for a short time
• Something transitory
• Border secured in record time -- it won't last