According to the FDA, not all plastic buckets are "safe" for storing food or water. Some plastics can leach harmful compounds into your water. To avoid this problem, you'll need to learn how to identify food grade buckets. All plastic pails should have a symbol stamped on the bottom to indicate whether food-safe plastic was used in its construction. The best type of plastic for long-term food or water storage is high-density polyethylene. HDPE, identified by the "2" symbol, is one of the most stable and inert forms of plastic. All plastic buckets sold specifically for food storage should be made from this material.