U. S. Food and Drug Administration
Center for Food Safety and Applied Nutrition
Office of Premarket Approval

GUIDANCE FOR SUBMITTING REQUESTS UNDER 21 CFR 170.39
Threshold of Regulation For Substances Used in Food-Contact Articles

Listed below is guidance for submitting a request to FDA for consideration under the threshold of regulation process established by 21 CFR 170.39 (Final rule published on July 17, 1995; 60 FR 36582). Requests should be limited to only those substances used in food packaging or food processing equipment that are not designed to have a technical effect on the food itself.

Three copies of the request should be submitted. The request should contain the following information:

1. The chemical composition of the substance for which the request is made, including, whenever possible, the name of the chemical in accordance with current Chemical Abstract Service (CAS) nomenclature guidelines and a CAS Registry Number, if available;

2. The intended technical effect of the substance in the food-contact article (e.g., stabilizer, catalyst, defoamer);

3. Detailed information on the conditions of use of the substance (e.g., temperature, type of food with which the substance will come into contact, the duration of the contact, and whether the food-contact article will be for repeated or single use applications);

4. A clear statement as to whether the request for exemption from regulation as a food additive is based on the fact that the use of the substance in the food-contact article results in a dietary concentration at or below 0.5 ppb, or on the fact that it involves the use of a regulated direct food additive for which the dietary exposure is at or below 1 percent of the acceptable dietary intake (ADI);

5. Data that will enable FDA to estimate the daily dietary concentration resulting from the proposed use of the substance, except in those cases where FDA has historically not requested such data. (For example, FDA has not asked for such data when the substance is an alloy that is resistant to corrosion and abrasion. Instead, the agency has requested information on the properties of the alloy (e.g., hardness) that enable it to resist corrosion and abrasion. However, if the alloy is relatively soft, or contains active metals, or there is reason to suspect the presence of heavy metal contaminants (e.g., Pb, Cd, and Hg), the requestor should consult FDA for specific advice on the types of information that will be required.)
   (a) These data should be either in the form of:
   (i) Validated migration data obtained under worst-case (time/temperature) intended use conditions utilizing appropriate food simulating solvents as discussed in Recommendations for Chemistry Data for Indirect Food Additive Petitions or

   (ii) Level of the substance used in the manufacture of the food contact article or the residual level of the substance present in the finished food-contact article. These data should be used to estimate a worst-case dietary concentration level assuming 100% migration to food. The agency recognizes that there may be cases in which mitigating circumstances make it highly unlikely that all of the substance would migrate to food. In such cases, submissions should include a detailed discussion of any factors that are likely to significantly decrease the extent of migration of the substance to food.

   (b) The submission should also include a detailed description of the analytical method used to quantify the substance along with data used to validate the method. In cases where there is no detectable migration into food or food stimulants, or when no residual level of a substance is detected in the food-contact article by a suitable analytical method, the validated detection limit of the method used to analyze for the substance should be considered in estimating the dietary concentration. Submissions, in such cases, should include the data used to validate the method's detection limit.

   (c) For repeat-use articles, the submission should include an estimate of the amount of food that contacts a specific unit of surface area over the lifetime of the article.

   (d) A detailed discussion of how to estimate the dietary concentration resulting from the intended use of a substance in a food-contact article can be found in Recommendations for Chemistry Data for Indirect Food Additive Petitions. Interested persons are also encouraged to obtain specific guidance from FDA's Office of Premarket Approval (HFS-200, 200 C Street SW, Washington, DC 20204) on the appropriate protocols to be used for obtaining migration data, on the validation of the analytical methods used to quantify migration levels, on the procedures used to relate migration data to dietary exposures, and on any other issue not specifically covered in these guidelines.

6. The results of a literature search of existing toxicological information on the substance and its impurities. This information is needed to determine whether an animal carcinogen bioassay has been carried out, or whether there is some other basis for suspecting that the substance is a carcinogen or potent toxin. This information on the impurities is needed to determine whether any of them are carcinogenic and, if carcinogenic, whether their TD₅₀ values are greater then 6.25 mg/kg bodyweight per day, in accordance with 21 CFR 170.39(a)(1).

7. Information that will enable FDA to evaluate the environmental impact resulting from the manufacture, use, and disposal of the substance in the food-contact article. This information should usually be in the form of an abbreviated environmental assessment (EA) as specified in 21 CFR 25.31a(b)(1) or (2). The following guidance documents provide assistance in the preparation of the appropriate EA:
   • Abbreviated EA For Functional Components of Finished Food Packaging Present at 5% or Less by Weight

   • Abbreviated EA For Nonfunctional Components of Finished Food Packaging Present at 5% or Less by Weight

   • Abbreviated EA For Additives to be Used as Components of Food-Contact Surfaces of Permanent or Semi-Permanent Equipment or of Other Food-Contact Articles Intended for Repeated Use

   If a requestor believes that the abbreviated EAs specified in 21 CFR 25.31(a)(b)(1) and (2) are not appropriate for the intended use of a particular substance in a food-contact article, the requestor should consult FDA's Office of Premarket Approval (address above) for further guidance.

Exemptions for Houseware Articles

In the past, FDA typically has not required food additive petitions containing the data described in item 5 above for food-contact articles used exclusively in the home or in restaurants. Although components of houseware articles that are reasonably expected to become components of food are food additives subject to premarket approval, in most cases, the use of such articles results in trivial levels of migration to food either because of short contact times or because the articles are manufactured using materials (e.g., alloys and ceramics) that pose little likelihood of migration to food. Therefore, the agency, because of limited resources, has not enforced the food additive provisions of the FD&C; Act for such cases unless there is evidence of a potential health hazard. However, FDA cannot issue a binding "exemption from regulation" under 21 CFR 170.39 for houseware articles in the absence of information to show that the use of such articles would result in, or would reasonably be expected to result in, dietary concentrations below the "threshold". FDA is particularly concerned with single-service houseware articles that contain components that have the potential for migrating to food in significant amounts (i.e., would result in dietary concentrations above the threshold of regulatory concern). Therefore, the data described in item 5 above will also be required for any submission requesting an exemption for the use of a substance in a single-service houseware article. For repeat-use articles, the submission may need to include an estimate of the amount of food that contacts a specific unit of surface area over the lifetime of the article. The requestor should consult FDA as to whether such data will be needed for a specific repeat-use houseware article.