Animal & Veterinary


Dioxins and polychlorinated biphenyls (PCBs) are groups of compounds. Some of the dioxin and PCB congeners may be carcinogens at low levels of exposure over extended periods of time.

  • There are no tolerances or other administrative levels established by the FDA for dioxins in feed. 
  • Temporary tolerances for PCBs in animal feed can be found in 21 CFR 509.30.
  • FDA, in conjunction with the European Union and the U.S. EPA and  USDA, is addressing both international and domestic dioxin and PCB concerns in animal feed.  One example of each is provided below.

Domestic Dioxin Concern

In July 1997, FDA found contamination of animal feeds with dioxin, which resulted in elevated levels of dioxin in chickens, eggs and catfish. Dioxin contamination was found in animal feeds distributed to over 3,400 consignees throughout the country.

FDA's Response

  • The source of the dioxin contamination was traced to a mined clay product called "ball clay," which is used as an anti-caking agent in soybean meal, in other feed components, and in complete animal feeds. 
  • CVM worked cooperatively with the affected industries to halt any further distribution and use of the feed known to be contaminated with dioxin. This was carried out across the country.
  • In 1999, ball clay was not accepted for use as an ingredient by the Association of American Control Officials, Inc.
  • In FY 1998, FDA initiated steps to determine whether other mined clay products and naturally derived anticaking agents were contaminated with dioxin. 
  • Industry associations met with CVM to determine the type of information needed, which resulted in a compilation of industry sampling of anticaking agents for dioxins.
  • FDA, with analytical assistance from EPA, surveyed mined feed ingredients for the presence of dioxins, as a supplement to industry sampling.

International PCB Concern

FDA received information that fat from a rendering company in Belgium was contaminated with PCBs and dioxin in January of 1999. This product was shipped to animal feed manufacturers and incorporated into animal feed distributed to poultry, hog and cattle farms in Belgium, France, and the Netherlands, with the majority of the product going to Belgium. Analysis of chickens and eggs in Belgium revealed elevated PCBs levels and low levels of dioxins.

FDA's Response

  • On June 4,1999 FDA issued an Import Bulletin to the field directing animal feed, and animal by-products for animal food from France, Belgium and Netherlands, and egg-containing products, from Belgium offered for entry into the U.S. to be held at the port of entry.
  • On June 11, 1999 FDA issued Import Alert 99-24, "Detention Without Physical Examination of Human Food Products and Animal Feeds Contaminated with Dioxin and/or PCB Compounds".
  • On August 23, 1999, FDA issued a guidance representing the Agency's current thinking on possible dioxin/PCB contamination of animal source material in EU countries: Guidance for Industry: Possible Dioxin/PCB Contamination of Drug and Biological Products.

Page Last Updated: 02/03/2017
Note: If you need help accessing information in different file formats, see Instructions for Downloading Viewers and Players.
Language Assistance Available: Español | 繁體中文 | Tiếng Việt | 한국어 | Tagalog | Русский | العربية | Kreyòl Ayisyen | Français | Polski | Português | Italiano | Deutsch | 日本語 | فارسی | English