Foreign Matter

Foreign matter is anything in a food that does not belong there, from insect or rodent matter to stones, metal or glass. It can point to unsanitary handling, and hard or sharp pieces can injure the person eating it.

  • Food safety
  • Physical hazards & pests

Foreign matter is a catch-all term for material in a food that is not part of the food itself. FDA's filth and extraneous materials program describes extraneous material as foreign matter linked to objectionable conditions or practices during production, storage or distribution. It falls into two broad groups. The first is filth, such as insect, rodent or bird matter, which mainly signals unsanitary conditions. The second is hard or sharp objects, such as metal, glass or stones, which can cause physical injury. Natural parts of a food that consumers expect, like a bit of nut shell, are generally treated separately under FDA's hard-object policy.

Hard or sharp pieces can cause trauma or serious injury, and FDA considers a ready-to-eat food containing such an object 7 to 25 mm long to be adulterated. Filth matters even when it is not directly harmful, because it shows that pests or poor practices reached the food. Federal rules require food makers to use quality control operations that keep natural or unavoidable defects at the lowest level currently feasible, and they forbid mixing a defective lot into clean food to dilute it.

Key facts

Hard or sharp object size of concern
7 to 25 mm in ready-to-eat food
FDA hazard cases reviewed
About 190, from 1972 to 1997
Blending defective lots
Not permitted (21 CFR 117.110)
USDA Meat and Poultry Hotline
1-888-674-6854

In a bakery or commercial kitchen

  • Inspect and segregate incoming flour, sugar, nuts and other ingredients, then store them so they stay protected from contamination
  • Hold ingredients prone to pests or extraneous material to FDA's natural-defect limits before they go into production
  • Put adequate measures in place, suited to your process, to keep metal and other extraneous material out of food
  • Never blend a lot that exceeds a defect action level into good product; the final mix is still adulterated
  • Treat any hard or sharp object 7 to 25 mm long in a ready-to-eat item as a safety issue, not a cosmetic flaw

For home and cottage bakers

  • Report a foreign object in meat, poultry or egg products to the USDA hotline at 1-888-674-6854
  • Report foreign objects in other foods to FDA at 888-SAFEFOOD (888-723-3366)
  • Contact a healthcare provider if someone is hurt, and call 911 in an emergency
  • Know that natural pieces such as nut-shell fragments are handled differently from metal or glass under FDA policy

Related entries

Sources

Written by VanillaGoods in our own words from these sources. Last reviewed October 17, 2026.

  1. Filth and Extraneous Materials Program, U.S. Food and Drug Administration
  2. CPG Sec. 555.425 Foods, Adulteration Involving Hard or Sharp Foreign Objects, U.S. Food and Drug Administration
  3. 21 CFR 117.110 Defect action levels, Legal Information Institute, Cornell Law School (Code of Federal Regulations)
  4. 21 CFR 117.80 Processes and controls, Legal Information Institute, Cornell Law School (Code of Federal Regulations)
  5. How to Report a Problem with Food, FoodSafety.gov (U.S. Department of Health and Human Services)