Samples containing four types of high moisture content foreign material were placed in warehouses to determine how this material may contribute to aflatoxin formation in peanuts during storage. The high moisture material included gherkins, maypops, briarballs, and citrons. Results showed aflatoxin levels exceeding 700 ppb in some shelled peanut samples. Frequency tests showed 9% of all grade samples from farmers stock lots contained high moisture foreign material. When averaged across an entire warehouse, the high moisture foreign material could raise the average aflatoxin level in storage by 30 ppb.