Spam traps are email addresses that should never be on a legitimate marketer's list. Pristine spam traps are addresses published online to catch scrapers. Recycled spam traps are former valid addresses reactivated to catch senders with poor list hygiene. Hitting spam traps damages sender reputation and can lead to blacklisting. Prevention: use double opt-in, validate emails, and remove unengaged subscribers regularly. MisarMail's list hygiene tool flags potential spam trap risk.