Constituent Update

June 17, 2021

Today, the U.S. Food and Drug Administration (FDA) issued a Threshold of Regulation (TOR) exemption for the use of metal carbides and metal carbide alloys as a component or ceramic coating in repeat-use applications such as parts in food processing equipment.

A TOR exemption is based on evidence that the dietary exposure level from the intended use of the food contact substance (FCS), is below 0.5 parts per billion (ppb) and the FCS itself is not a known carcinogen. TOR exemptions may be used by any manufacturer or supplier for the specified uses of the FCS under the intended conditions of use. Federal law requires companies who wish to use a food additive obtain pre-market authorization from the FDA.  Authorization for food contact substances is typically obtained through the submission of a Food Contact Substance Notification (FCN) to FDA.  A FCN authorization applies only to the food contact substance prepared by the manufacturer identified in the FCN.

The FDA took this action because it has reviewed the use of metal carbides in food processing equipment through numerous FCNs and has received other inquiries on its use. Based on FDA’s reviews, the agency concluded that metal carbides remain stable and intact, chemically inert, and resistant to corrosion and abrasion under their intended conditions of use. There is little or no likelihood that components of metal carbides would migrate to food at other than insignificant amounts, nor would the metal carbides otherwise affect food and therefore, the agency has no safety concerns from this intended use. In addition, the FDA is not aware of any study showing these food contact substances to be carcinogenic in humans or in animals.

This agency-initiated TOR exemption (TOR-2021-003) allows for the use of these substances in repeat-use applications without the requirement of an FCN.  Reducing the number of duplicative submissions the agency receives for metal carbide and metal carbide alloy uses is consistent with the FDA’s risk-based approach and conserves the agency’s resources for issues of greater public health significance.

For additional information

• About the FCS Review Program
• Threshold of Regulation (TOR) Exemptions Table
• Guidance for Industry: Submitting Requests under 21 CFR 170.39 Threshold of Regulation for Substances Used in Food-Contact Articles
• Inventory of Effective Food Contact Substance (FCS) Notifications