Use of Recycled Plastics in Food 
Packaging (Chemistry Considerations): 
Guidance for Industry  
 
Additional copies are available from: 
Office of Food Additive Safety 
Division of Food Contact Substances HFS-275 
Center for Food Safety and Applied Nutrition 
Food and Drug Administration 
5001 Campus Drive 
College Park, MD  20740 
(Tel) 240-402-1175 
 
https://www.fda.gov/FoodGuidances 
 
You may submit electronic or written comments regarding this guidance at any time.  Submit 
electronic comments to https://www.regulations.gov.  Submit written comments to the 
Dockets Management Staff (HFA-305), Food and Drug Administration, 5630 Fishers Lane, 
rm. 1061, Rockville, MD 20852.  All comments should be identified with docket number 
FDA-2020-D-1456 and with the title of the guidance document.   
 
 
U.S. Department of Health and Human Services 
Food and Drug Administration 
Center for Food Safety and Applied Nutrition  
 
July 2021 
 
OMB Control No. 0910-0495 
Current expiration date available at https://www.reginfo.gov/public/do/PRAMain  
*See additional PRA statement in Section IX of this guidance 
 
 
 
This is a revision to this guidance, which was originally issued in August 2006.  Revisions are 
noted by date at the end of the guidance.  Contains Nonbinding Recommendations 
Table of Contents 
 
 
I. Introduction ................................................................................................................................. 3 
II. Background ................................................................................................................................ 3 
III. Recycling Processes .................................................................................................................. 5 
A. Pre-Consumer Scrap:  Primary Recycling ................................................................ 5 
B. Physical Reprocessing:  Secondary Recycling ......................................................... 5 
C. Chemical Reprocessing:  Tertiary Recycling ........................................................... 6 
IV. Exposure to Chemical Contaminants ........................................................................................ 7 
V. Surrogate Contaminant Testing ................................................................................................. 9 
A. Choice of Surrogates ............................................................................................... 9 
B. Contamination of the Plastic .................................................................................. 10 
C. Other Considerations ............................................................................................. 11 
VI. Plastic Containers from Non-Food-Contact Applications as Feedstock ................................ 12 
VII. Use of an Effective Barrier .................................................................................................... 15 
VIII.   Elimination of Data Recommendations for 3 Recycling Processes for PET and PEN .. 16 
Appendix 1. Model of the Sorption of Surrogate Contaminants into Plastic ............................... 16 
IX. Paperwork Reduction Act of 1995 ......................................................................................... 19 
X.  References ............................................................................................................................... 19 
Document History ......................................................................................................................... 20 
Endnotes ........................................................................................................................................ 21 
 
   
2 
  Contains Nonbinding Recommendations 
Use of Recycled Plastics in Food 
Packaging (Chemistry Considerations): 
1
Guidance for Industry   
 
 
This guidance represents the current thinking of the Food and Drug Administration (FDA or we) 
on this topic.  It does not establish any rights for any person and is not binding on FDA or the 
public.  You can use an alternative approach if it satisfies the requirements of the applicable 
statutes and regulations.  To discuss an alternative approach, contact the FDA staff responsible 
for this guidance at the phone number listed on the title page.  
 
 
 
I. Introduction  
The purpose of this document is to highlight the chemistry issues that FDA recommends that a 
manufacturer of recycled plastic consider during the manufacturer's evaluation of a recycling 
process for producing material suitable for food-contact applications.  This document supersedes 
the December 1992 Points to Consider for the Use of Recycled Plastics in Food Packaging:  
Chemistry Considerations (1992 Points to Consider).  The possibility that chemical 
contaminants in plastic materials intended for recycling may remain in the recycled material and 
could migrate into the food the material contacts is one of the major considerations for the safe 
use of recycled plastics for food-contact applications.  Other aspects of plastics recycling, such as 
microbial contamination and structural integrity of the recycled plastic, are also important, but 
are not discussed in this document. 
 
FDA's guidance documents, including this guidance, do not establish legally enforceable 
responsibilities.  Instead, guidances describe our current thinking on a topic and should be 
viewed only as recommendations, unless specific regulatory or statutory requirements are cited.  
The use of the word should in FDA guidances means that something is suggested or 
recommended, but not required.  
 
II. Background 
Glass, steel, aluminum, and paper are recycled for food-contact use.  Post-consumer use 
contamination is not a major concern with glass and metals.  These materials are generally 
impervious to contaminants and are readily cleaned at the temperatures used in their recycling.  
 
1 This guidance has been prepared by the Office of Food Additive Safety, Division of Food Contact Substances in 
the Center for Food Safety and Applied Nutrition at the U.S. Food and Drug Administration.   
3 
  Contains Nonbinding Recommendations 
In addition, pulp from reclaimed fiber in paper and paperboard may be used for food-contact 
articles, provided it meets the criteria in Title 21 of the Code of Federal Regulations,  176.260 
(Pulp from reclaimed fiber). 
 
Manufacturers of food-contact articles made from recycled plastic are responsible for ensuring 
that, like virgin material, recycled material is of suitable purity for its intended use and will meet 
all existing specifications for the virgin material.  These requirements, which are described in 
21 CFR parts 174 through 179, serve as the framework for the testing protocol and evaluation 
procedures outlined in this guidance document.  In particular,  174.5 (General provisions 
applicable to indirect food additives), subparagraph (a)(2) states, [a]ny substance used as a 
component of articles that contact food shall be of a purity suitable for its intended use. 
 
Several general methodologies exist by which plastic packaging can be recycled, and each 
presents distinct issues regarding the contaminant residues that may be present in post-consumer 
material.  Below, FDA presents a preliminary discussion of the basic types of recycling and 
identifies specific concerns associated with each type.  This guidance then describes a 
recommended approach for estimating the maximum level of a chemical contaminant in the 
recycled material that would result in an estimated daily intake (EDI) that does not exceed 1.5 
micrograms/person/day (0.5 parts per billion (ppb) dietary concentration (DC)), the level that 
FDA would generally consider to be of negligible risk for a contaminant migrating from recycled 
plastic.  Finally, the guidance recommends a protocol for developing chemistry data that would 
be useful for evaluating the adequacy of a recycling process to remove chemical contaminants.  
FDA notes that the testing protocol and evaluation procedures recommended in this guidance 
may change as new knowledge is acquired. 
 
The following changes to the testing protocol and evaluation procedures that were previously 
recommended in the 1992 Points to Consider are included in this document: 
 
  Lowering from 1 ppb to 0.5 ppb the DC that FDA would generally consider to be of 
negligible risk for a contaminant migrating from recycled plastic.  These DCs correspond 
to EDIs of 3 micrograms/person/day and 1.5 micrograms/person/day, respectively. 
  Increasing the number of recommended options for surrogate contaminants for use in 
evaluating a recycling process. 
  Eliminating the recommendation to include a heavy metal contaminant in the surrogate 
testing of recycling processes for polyethylene terephthalate (PET). 
  Providing recommendations to address secondary recycling of plastics for cases in which 
plastic containers from non-food-contact applications (those that originally contained, 
e.g., household cleaners, soaps, shampoos, or motor oil) are included in the post-
consumer feedstock. 
  Eliminating all data recommendations for tertiary recycling processes for PET and 
polyethylene naphthalate (PEN). 
  Recommending the use of 0.05 as the default consumption factor (CF) for any plastic 
recycled for food-contact use. 
 
Although not required by law or regulation, recyclers of plastics intended for the manufacture of 
food-contact articles are invited to submit information on their recycling process to FDA for 
4 
  Contains Nonbinding Recommendations 
evaluation and comment.  Please send submissions to the Office of Food Additive Safety 
(OFAS) at the address given on the cover of this guidance. 
 
III. Recycling Processes  
The different approaches to the recycling of plastic packaging materials can be categorized into 
three distinct processes.  Primary recycling (1) refers to the use of pre-consumer industrial scrap 
and salvage to form new packaging, a common practice in industry.  Secondary recycling (2) 
refers to the physical reprocessing (e.g., grinding and melting) and reformation of post-consumer 
plastic packaging materials.  Tertiary recycling (3) involves subjecting post-consumer plastic 
packaging to chemical treatment whereby its components are isolated and reprocessed for use in 
manufacture. 
 
 Recycling is the processing of waste to make new articles.  Because bottles intended for reuse 
are not made to be discarded and become waste, reuse is not considered recycling.  Rather, reuse 
is regarded simply as one form of source reduction, i.e., minimizing the amount of material 
entering the environment.  In simple reuse, the package remains intact and is reused in its 
original form.  In secondary and tertiary recycling, the original package is destroyed and new 
packaging is formed from the remains.  This guidance focuses on the recycling of plastic 
packaging materials, and reuse will not be discussed further. 
 
A. Pre-Consumer Scrap:  Primary Recycling  
Primary recycling is the recycling of industrial scrap produced during the manufacture of food-
contact articles and is not expected to pose a hazard to the consumer.  The recycling of this scrap 
is acceptable, provided good manufacturing practices are followed.  If this scrap is collected 
from several different manufacturers, however, FDA recommends that the recycler consider 
whether the level and type of adjuvants in the recycled plastic would comply with existing 
approvals. 
 
B. Physical Reprocessing:  Secondary Recycling  
Physical reprocessing involves grinding, melting, and reforming plastic packaging material.  The 
basic polymer is not altered during the process.  Prior to melting and reforming, the ground, 
flaked, or pelletized polymer is generally washed to remove contaminants.  The size of the 
polymer flakes or pellets can influence the effectiveness of the washing.  Smaller particles 
provide a greater surface area for enhancing the effectiveness of the wash.  Different polymers 
may also undergo different reforming conditions, such as different processing temperatures, the 
use of vacuum stripping, or other procedures, that could influence contaminant levels.  In some 
cases, during the grinding or melting phases, the reprocessed material may be blended with 
virgin polymer. 
 
Recyclers should be able to demonstrate that contaminant levels in the reformed plastic are 
reduced to sufficiently low levels to ensure that the resulting packaging is of a purity suitable for 
its intended use.  To produce a polymer with the desired qualities, however, additional 
antioxidants, processing aids, or other adjuvants may need to be added to the recycled polymer.  
The type and total amount of these additives must comply with existing statutory and regulatory 
5 
  Contains Nonbinding Recommendations 
authorizations, and any adjuvants already in the plastic should not react during the recycling 
process to form substances whose safety has not been evaluated by FDA (see 21 CFR part 174)2.  
Use in the recycled polymer of a new additive or an amount of an approved additive in excess of 
what is currently authorized for the virgin polymer would require a food contact substance 
notification (FCN) or food additive petition (FAP) (see Packaging and Food Contact Substances 
(FCS) ). 
 
A secondary recycling process presents some unique challenges that might cause it to be 
inappropriate for the production of food-contact articles, particularly if the recycler had little or 
no control over the waste stream entering the recycling facility (e.g., commingling of food-
contact and non-food-contact materials).  Where effective source control or sorting procedures 
can be established, however, the potential for post-consumer food-contact materials to be 
recycled together with other post-consumer plastics will be minimized or eliminated.  Even if all 
the incoming post-consumer polymer were comprised of food-contact materials, limitations on 
food type or conditions of use could be compromised in the finished recycled product.  For 
example, an additive approved for use only in contact with aqueous food or only for refrigerated 
use could be incorporated into packaging intended for high-temperature use with fatty foods.  
The resulting food-contact article would not comply with existing approvals.  This concern may 
be mitigated by development of sorting procedures that result in reprocessing of only a single 
characteristic container, e.g., a polyethylene terephthalate (PET) soda bottle. 
 
FDA recommends that 2 recyclers address these concerns by, for example, implementing 
controls on the source of the post-consumer polymer, adequate sorting procedures for the 
incoming post-consumer material, use limitations on the finished recycled packaging (such as 
use at room temperature or below), or food-type restrictions (such as dry or aqueous foods only).  
We recommend including a discussion of these types of actions in manufacturer submissions to 
FDA regarding 2 recycling processes to help us evaluate the processes. 
 
C. Chemical Reprocessing:  Tertiary Recycling  
The primary goal of tertiary recycling is the regeneration of purified starting materials.  
Chemical reprocessing may involve depolymerization of the used packaging material with 
subsequent regeneration and purification of resulting monomers (or oligomers).  The monomers 
are then repolymerized and the regenerated or reconstituted polymer is formed into new 
packaging.  Regenerated monomer, polymer, or both may be blended with virgin materials.  The 
regeneration process may involve a variety of monomer/polymer purification steps in addition to 
washings, such as distillation, crystallization, and additional chemical reaction.  
 
2 For additional information see Determining the Regulatory Status of Components of a Food Contact Material. 
6 
  Contains Nonbinding Recommendations 
IV. Exposure to Chemical Contaminants 
FDA believes that acute consumer exposure to chemical contaminants from food containers 
produced from plastic that was processed by 2 or 3 recycling will be extremely low because of 
the low concentrations of contaminant residues in the recycled polymers (see below).  It is 
possible, however, that traces of a toxic contaminant could be carried through a 2 or 3 
recycling process, become a part of the packaging, and migrate into food in contact with the 
packaging.  Although subsequent recycling of the packaging will result in dilution of the 
contaminant, a very low steady-state concentration of certain contaminants could conceivably 
develop in the recycled material over the long term.  Therefore, there is a potential for a 
consumer to be exposed to low concentrations of a particular contaminant over a long period of 
time.  To develop a recommendation for the maximum acceptable level(s) of residual 
contaminants in the recycled material, FDA considered the question of risk in a probabilistic way 
rather than on a compound-by-compound basis. 
 
To recommend a maximum acceptable level for chemical contaminants in recycled food-contact 
articles that can form the basis of Good Manufacturing Practice with respect to recycled material, 
FDA determined the residual concentration of a contaminant that corresponds to an acceptable 
upper limit of dietary exposure.  Using the scientific analysis supporting the Threshold of 
Regulation approach to evaluating indirect food additives as a basis (see 21 CFR 170.39), FDA 
believes that EDIs of contaminants from recycled food-contact articles on the order of 1.5 
micrograms/person/day (0.5 ppb DC) or less are generally of negligible risk.  The following 
exercise illustrates the calculation of the maximum acceptable level in the plastic of a 
contaminant in PET that would result in an EDI of no more than 1.5 micrograms/person/day. 
 
In the case of PET, combining its density of 1.4 grams per cubic centimeter (g/cm3) with an 
assumed container thickness of 0.50 millimeters (mm) (~0.02 inches (in)) gives a package with a 
mass-to-surface area ratio of 70 milligrams per square centimeter (mg/cm2) (450 mg/in2).  FDA 
further assumed the following:  individuals consume 3 kilograms (kg) of food per day, 10 grams 
(g) of food contacts one square inch of container, a consumption factor (CF) of 0.05 for recycled 
PET,[1] and a food-type distribution factor (f ) of 1.0 for all food types (see Guidance for 
T
Industry: Preparation of Premarket Submissions for Food Contact Substances (Chemistry 
Recommendations)).  The relationships among EDI, DC, and the CF, f , and migration level 
T
from package to food are as follows: 
 
 
 
EDI = DC  3 kg food/person/day 
 
where M is the concentration of migrant in a food simulant, i, where i represents the four 
simulated food types: aqueous, acidic, alcoholic, and fatty foods.  Use of the parameters noted 
above leads to: 
 
7 
  Contains Nonbinding Recommendations 
DC = 0.5 ppb = 0.05 = 0.05(M)(1.0) 
 
and = (0.5 x 10-9 g contaminant/g food)  (0.05) 
 
= 1 x 10-8 g contaminant/g food.  
 
Then, (450 x 10-3 g packaging/in2)  (10 g food/in2) = 0.045 g packaging/g food 
 
(1 x 10-8 g contaminant/g food)  (0.045 g packaging/g food) = 
 
2.2 x 10-7 g contaminant/g packaging, 
 
or 220 micrograms per kilogram (g/kg) of contaminant in the packaging material.  In other 
words, if a contaminant were present at 220 g/kg in the PET container made from the recycled 
material and if 100% migration of the contaminant into food were assumed (a conservative 
assumption for room-temperature applications of a high barrier material like PET), the DC of the 
contaminant would be 0.5 ppb (EDI:  1.5 g/person/day). 
 
The maximum acceptable level of a residual contaminant in a polymer that corresponds to an 
EDI equal to 1.5 g/person/day will depend on the polymer density, polymer thickness, and CF.  
The table below reflects residue levels in several polymers that would result in an EDI of a 
contaminant of 1.5 g/person/day.  These calculations were done using a CF of 0.05 for each 
recycled polymer,[1] a container wall thickness of 0.50 mm (~0.02 in), and the conservative 
assumptions that all food types are used with each polymer and that the finished article will 
consist of 100% recycled polymer. 
 
Recycled Polymer  Density, g/cm3  Maximum Residue 
PET  1.4  220 g/kg 
Polystyrene  1.05  300 g/kg 
PVC  1.58  200 g/kg 
Polyolefins  0.965  320 g/kg 
 
Thus, to achieve EDIs below 1.5 g/person/day for recycled containers of 0.50-mm thickness, 
individual chemical contaminants should not be present at levels greater than those given above.  
We emphasize that the calculated levels depend on the thickness of the packaging  the thicker 
the packaging, the lower the maximum residue levels should not exceed the 1.5 g/person/day 
EDI limit.  If a specialized use for a recycled polymer can be documented, it may be possible to 
estimate a lower CF for use in calculating a maximum acceptable contaminant level.  Finally, in 
cases in which recycled polymer is expected to be blended with virgin polymer, and thus, 
8 
  Contains Nonbinding Recommendations 
contaminants in the recycled polymer are diluted with virgin polymer, the maximum acceptable 
contaminant level calculated using FDAs recommended approach set out above may be divided 
by the fraction of recycled polymer in the blend. 
 
V. Surrogate Contaminant Testing 
FDA recommends simulating consumer misuse by exposing virgin polymer (either in container 
form or as flake) to selected surrogate contaminants and then running the exposed or 
challenged polymer through the recycling process to demonstrate the ability of a 2 or 3 
recycling process to remove contaminants from plastic containers or packaging that has been 
subjected to consumer misuse or abuse (e.g., through storage of pesticides or automotive 
chemicals).  Subsequent analysis of the processed polymer for the surrogate contaminants would 
provide a means to evaluate the efficacy of the recycling process. 
 
A. Choice of Surrogates  
FDA recommends that recyclers use materials that have a variety of chemical and physical 
properties to simulate consumer misuse.  In particular, FDA recommends that the surrogate 
contaminants represent common materials accessible to the consumer and include a volatile 
polar organic substance, a volatile non-polar organic substance, a non-volatile polar organic 
substance, a non-volatile non-polar organic substance, and a heavy metal salt (except for PET, 
see below).  Examples of recommended surrogates are given below.  FDA believes that one 
surrogate per category is sufficient for the testing. 
 
Volatile Polar 
Chloroform 
Chlorobenzene 
1,1,1-Trichloroethane 
Diethyl ketone 
 
Volatile Non-Polar 
Toluene 
 
Heavy Metal 
Copper(II) 2-ethylhexanoate 
 
Non-Volatile Polar 
Benzophenone 
Methyl salicylate 
 
Non-Volatile Non-Polar 
Tetracosane 
Lindane 
Methyl stearate 
Phenylcyclohexane 
9 
  Contains Nonbinding Recommendations 
1-Phenyldecane 
2,4,6-Trichloroanisole 
 
Chloroform and toluene are components of cleaning solvents; benzophenone is a suitable 
substitute for non-volatile polar pesticides such as Diazinon; and tetracosane is a good 
representative for the long-chain hydrocarbons that comprise motor oil.  A heavy metal salt such 
as copper(II) 2-ethylhexanoate, a substitute for the toxic salts commonly used in herbicides, 
would complete the range of properties noted.[2]  OFAS is available to discuss the use of 
surrogates other than those listed in the table above. 
 
In the case of PET, FDA does not recommend including a heavy metal salt in surrogate testing.  
In the PET recycling submissions reviewed over the past decade, migration of the heavy metal 
surrogate has never been detected in food simulants.  FDA reviewed data for a number of heavy 
metal surrogates, including the metal salts calcium monomethylarsonate (a herbicide for 
crabgrass), copper acetoarsenite (Paris green), cadmium acetate, zinc stearate, and copper(II) 2-
ethylhexanoate.  The data show that, unlike small organic molecules, metal salts do not sorb as 
readily into PET.  Also, the salts are more easily washed out of PET, probably because they 
simply adsorb to the PET surface.  In one case, the heavy metal surrogate was incorporated into 
the resin by blending and still was not detected in migration experiments.  FDA believes that the 
metal-containing substances to which consumers have access are primarily in the salt form, and 
even if this were not the case, it is unlikely that non-ionic organometallic species would behave 
any differently than the organic compounds represented by the four general surrogate categories. 
 
To date, surrogate testing data for recycling processes for polymers other than PET are 
insufficient to support general conclusions about the behavior of heavy metals in those polymers.  
Therefore, FDA continues to recommend the use of a heavy metal surrogate in the testing of 
recycling processes for polymers other than PET. 
 
B. Contamination of the Plastic  
To test the recycling process, FDA recommends the following approach. 
 
First, containers made of the virgin plastic of interest are contaminated or challenged by filling 
them with the surrogate contaminants, either neat or in at use concentrations, using a solvent 
such as hexane as a diluent.  An alternative approach that would reduce the amount of potentially 
hazardous wastes is to soak several kilograms of flaked virgin plastic of the type actually used in 
the recycling process in the selected contaminants at either neat or at use concentrations.  A 
mixture, or cocktail, of the contaminants could be used so long as the components of the 
cocktail do not react with each other.  Our recommendations for minimum concentrations of 
surrogates for a cocktail are shown in Table 1 below: 
 
   
10 
  Contains Nonbinding Recommendations 
Table 1. Examples of Minimum Concentrations of Contaminants in a Surrogate Cocktail 
 
Contaminant  Concentration 
Chloroform (volatile polar)  10% v/va 
Toluene (volatile non-polar)  10% v/v 
Benzophenone (non-volatile polar)  1% v/v 
Tetracosane or Lindane (non-volatile non-polar)  1% w/wb 
Copper(II) 2-ethylhexanoate (heavy metal)  1% w/w 
Balance:   
2-Propanol (as solvent for Cu(II) 2-ethylhexanoate)  10% v/v 
Hexane or Heptane (as overall solvent for cocktail)  68% v/v 
 
a  v/v - volume of contaminant per unit volume of entire cocktail 
b  w/w - mass of surrogate per unit mass of entire cocktail 
 
Once the bottles are filled or after the contaminants are thoroughly mixed with the flakes, the 
bottles or flakes should be stored sealed for two weeks at 40C with periodic agitation.  After the 
contaminants are drained and the bottles or flakes are rinsed, the concentration of each surrogate 
should be determined in the polymer.  The challenged polymer should then be subjected to the 
proposed recycling process, and regenerated components or packaging material formed from the 
reprocessed polymer should be analyzed for residual contaminants.  This approach represents a 
worst-case scenario, i.e., all material entering the recycling stream is assumed to be 
contaminated. 
 
Testing protocols may be submitted to OFAS for comment before any contamination studies are 
done.  FDA recommends that all analyses be validated as discussed in the Guidance for 
Industry: Preparation of Premarket  Submissions for Food Contact Substances (Chemistry 
Recommendations). 
 
C. Other Considerations  
If a proposed recycling process cannot be shown to remove contaminants to maximum 
acceptable levels under the scenario discussed above, then additional factors or limitations on use 
could justify a conclusion that the recycled package will not introduce contaminants into the diet 
at unacceptable levels.  The following additional factors/limitations may result in an acceptable 
upper limit of dietary exposure:  the use of a recycled/virgin blend, source controls, restricted 
uses, the fraction of contaminant that migrates into food or a food simulant, or the use of an 
effective barrier.  FDA recommends that the effect of measured or mathematically modeled 
factors be supported by adequate documentation (e.g., studies on a specific source control 
program, studies on the actual extent of contaminated material entering the recycling stream, or 
11 
  Contains Nonbinding Recommendations 
information that demonstrates that the recycled polymer is separated from food contact by an 
effective barrier). 
 
In cases where the post-consumer plastic feedstock is intended to consist of food containers only 
(i.e., intentionally excludes containers that were used to package non-food substances such as 
household cleaners), FDA would consider data submitted by recyclers that show the extent of 
contaminated material entering the recycling stream as a result of consumer misuse to 
demonstrate or allow a prediction of the actual incidence of chemical contamination of recycled 
articles.  FDA believes that, due to the incidental nature of potential consumer misuse of a food 
container and subsequent introduction of that container into the recycling stream, this 
information (if properly validated) can be factored into the exposure calculations to obtain more 
realistic values. 
 
VI. Plastic Containers from Non-Food-Contact Applications as 
Feedstock 
The 1992 Points to Consider was developed to address incidental contamination of food 
containers by consumers, following the original intended use of the containers.  Containers with 
non-food contents (e.g., household cleaners, furniture polish, shampoos, soaps, pesticides, or 
motor oil) were purposely not addressed. 
 
The amount of custom PET containers (i.e., containers other than soda bottles that are used to 
package specialty foods as well as non-food substances) collected via curbside programs has 
increased dramatically over the past several years[3] and is predicted to continue to increase 
(Plastics, 1996, and Adding, 1996).  In addition, the use of PET in non-food containers is 
increasing (PET, 1997).  These trends indicate that the contamination introduced into post-
consumer PET feedstock via non-food containers, as well as the probability that up to 100% of 
the post-consumer plastic feedstock might consist of non-food containers, are likely to increase.  
Therefore, FDA recommends that worst-case contamination assumptions be made for non-food 
containers entering the recycling stream (see below). 
 
FDA believes that the following two questions are relevant in determining the appropriateness of 
recycling non-food containers into new food containers by 2 processes: 
 
1.  Is the non-food container plastic, its adjuvants, and the adjuvant levels in the plastic 
currently authorized for use in contact with food?  FDA believes that it is highly unlikely 
that 2 recycling processes will remove unapproved adjuvants (such as colorants or 
antioxidants) because these substances are incorporated into the polymer matrix during 
manufacture. 
2.  Can the levels of chemical contaminants introduced into the post-consumer feedstock by 
non-food containers, which can sorb relatively large amounts of chemicals from their 
contents over very long shelf lives, be sufficiently reduced so that finished recycled 
containers are suitable for food-contact use?  FDA believes that it is likely that 2 
recycling processes could remove residual amounts of non-food substances such as 
household cleaning solutions from non-food containers because these substances are 
simply sorbed into the container's surface. 
12 
  Contains Nonbinding Recommendations 
 
These questions have been addressed for PET: 
 
1.  FDA received information from the plastics industry that verifies that all PET resin used 
to manufacture containers in the U.S. is authorized for food-contact use, i.e., food-grade 
PET is used to manufacture both food and non-food containers. 
2.  FDA used a mathematical model, based on Fick's law of diffusion, to predict the amount 
of a contaminant (represented by the surrogate contaminants described above) that will 
sorb into a PET bottle during a period of one year at 25C, the shelf life and use 
temperature of a typical non-food substance packaged in PET (see Appendix I).  Because 
the model tends to overpredict sorption (see Appendix I), FDA's experimental sorption 
results and data from the literature were also used to calculate the sorption of several 
surrogates into PET under these use conditions (Begley et al., 2002, and Demertzis et 
al., 1997).  The PET sorption values for several surrogates are summarized in Table 2 
below. 
 
FDA recommends that recyclers who wish to include non-food PET containers in their feedstock 
establish that the concentrations of the surrogates in challenged PET flake, prior to its being run 
through their recycling process, are greater than or equal to the sorption values shown in Table 2.  
FDA does not recommend that this criterion be included in surrogate testing for a recycling 
process that uses only food containers as feedstock  simply exposing virgin flake or intact 
bottles to the surrogate cocktail for 2 weeks at 40C is sufficient to model incidental misuse of 
containers by consumers. 
 
Table 2. Sorption of Surrogate Contaminants into PET After 365 Days at 25C  
 
Sorption 
Value 
Surrogate  Category  (mg/kg)  Reference 
Chloroform  Volatile polar  4860  Begley et al., 2002 (modeled 
value) 
Chlorobenzene  Volatile polar  1080  Demertzis et al., 1997a 
1,1,1-Trichloroethane  Volatile polar  1050  Demertzis et al., 1997a 
Diethyl ketone  Volatile polar  4860  Assumed to be the same as 
chloroform, based on similar 
molecular weights 
Toluene  Volatile non-polar  780  Begley et al., 2002 
Benzophenone  Non-volatile polar  49  Begley et al., 2002 
Methyl salicylate  Non-volatile polar  200  Begley et al., 2002 
13 
  Contains Nonbinding Recommendations 
Sorption 
Value 
Surrogate  Category  (mg/kg)  Reference 
Tetracosane  Non-volatile non- 154  Begley et al., 2002 (modeled 
polar  value) 
Lindane  Non-volatile non- 750  Begley et al., 2002 
polar 
Methyl stearate  Non-volatile non- 150  Assumed to be the same as 
polar  tetracosane, based on 
preliminary FDA experimental 
results 
Phenylcyclohexane  Non-volatile non- 390  Demertzis et al., 1997a 
polar 
1-Phenyldecane  Non-volatile non- 170  Demertzis et al., 1997a 
polar 
2,4,6-Trichloroanisole  Non-volatile non- 1100  Based on value for lindane with 
polar  molecular weight correction 
 
aThese values were measured at 40C. 
 
To obtain the initial concentrations shown in Table 2, FDA recommends exposing PET flake 
rather than intact bottles to the surrogate solutions for at least 14 days at 40C.  The use of intact 
PET bottles in surrogate testing potentially can result in at least an order of magnitude less 
sorption of the surrogate contaminants than the values shown in Table 2, due to the lower surface 
area of a PET bottle compared to an equal mass of flake (Komolprasert and Lawson, 1995).  We 
also recommend that a surrogate cocktail contain, at a minimum, the concentrations of 
contaminants given in Table 1 above.  Finally, FDA recommends that recyclers consider using 
higher concentrations of volatile surrogates such as chloroform in the cocktail to offset losses 
that could occur before the flake is analyzed.  
 
FDA recommends that, in cases in which the starting concentrations are found to be lower than 
the values in Table 2, recyclers correct for the shortfall by multiplying the surrogate testing 
results by a simple factor.  For example, if the actual starting concentration of toluene were 500 
mg/kg, then the factor would be 1.6 ((780 mg/kg)/(500 mg/kg) = 1.6). 
 
FDA recommends against analyzing actual batches of post-consumer plastics for potential 
chemical contaminants to refine exposure calculations because these analyses provide only a 
snapshot of the composition of curbside-collected plastic containers, and there is no guarantee 
that the composition of non-food containers in curbside recycling programs will remain the same 
over time. 
14 
  Contains Nonbinding Recommendations 
 
Recyclers who already had their PET recycling processes evaluated by FDA should not assume, 
based on the conclusions in this guidance document, that their letters from FDA apply to the use 
of non-food PET containers as feedstock.  If these recyclers want FDAs opinion on their use of 
non-food PET containers, they may ask us to reevaluate their surrogate testing data and issue a 
separate letter. 
 
VII. Use of an Effective Barrier 
The use of 2 or 3 recycled material as a non-food-contact layer of a multilayer food package is 
a potential application for recycled plastics.  FDA believes that this use would not present a 
concern about potential contaminant migration into food as long as the recycled polymer is 
separated from the food by an effective barrier made from virgin polymer or other appropriate 
material, e.g., an aluminum film.  Based on experimental and mathematically modeled diffusion 
data obtained by CFSAN scientists (and others) for three-layered coextruded PET films in which 
the center layer contained surrogate contaminants and the outer layers were comprised of virgin 
material (Piringer et al., 1998), FDA determined that virgin PET is an effective barrier to 
contaminants that could potentially migrate from a recycled plastic inner layer under the 
following conditions: 
 
1.  at a thickness  25 micrometers (m) (~0.001 in) at room temperature and below, and 
2.  at a thickness  50 m (~0.002 in) at higher temperatures, including use as a dual-
ovenable container for cooking food at 150C for 30 min, provided that only food 
containers are used in the feedstock to manufacture the recycled layer. 
 
In these cases, the presence of a virgin PET layer ensures that migration of a contaminant to food 
will result in an EDI no greater than 1.5 g/person/day.  The calculation assumes a consumption 
factor (CF) of 0.05 for recycled plastic packaging.[1]  [Note: Although an EDI  1.5 
g/person/day for a contaminant is generally of negligible safety concern, a substance 
intentionally used as a component of a food-contact article is still subject to the food additive 
definition and might require FDA premarket approval via a food contact substance notification 
(see Guidance for Industry: Preparation of Food Contact Notifications (Administrative)) or a 
Threshold of Regulation submission (see Guidance for Industry: Submitting Requests Under 21 
CFR 170.39 Threshold of Regulation for Substances Used in Food-Contact Articles), even if the 
EDI of the substance is  1.5 g/person/day.] 
 
To demonstrate that a given thickness of a virgin polymer functions as an effective barrier to the 
migration of contaminants, FDA recommends that the recycler subject intentionally 
contaminated polymer to the recycling process and incorporate the recycled polymer into a non-
food-contact layer of a finished article, using virgin polymer as the barrier layer.  FDA 
recommends that migration studies be performed with food simulants as described in the 
Guidance for Industry: Preparation of Premarket Submissions for Food Contact Substances 
(Chemistry Recommendations).  If migration studies show that the EDI of individual 
contaminants would not exceed 1.5 g/person/day, FDA would consider the virgin layer of the 
specified thickness to be an effective barrier to contaminants migrating from the non-food-
contact layer of recycled material.  If data from studies other than migration experiments 
15 
  Contains Nonbinding Recommendations 
establish that a given thickness of a particular polymer is sufficiently impermeable under 
anticipated time/temperature use conditions, those data could serve to replace migration 
experiments. 
 
VIII.  Elimination of Data Recommendations for 3 Recycling 
Processes for PET and PEN 
Based on a comprehensive review of all surrogate testing data submitted over the past decade for 
3 recycling processes for PET and polyethylene naphthalate (PEN), FDA concludes that 3 
recycling of PET or PEN by methanolysis or glycolysis results in the production of monomers or 
oligomers that are readily purified to produce a finished polymer that is suitable for food-contact 
use.  Both 3 processes will clean the polyester sufficiently to allow it to be considered of 
suitable purity, even assuming 100% migration of residual surrogate to food.  This is a 
significant difference from the surrogate testing of 2 recycling processes.  Secondary recycling 
processes often produce PET that is insufficiently cleaned to withstand 100% migration 
calculations for the residual surrogates.  Under these circumstances, FDA recommends 
additional migration tests to demonstrate that the finished PET meets the 1.5 g/person/day EDI 
limit. 
 
Based on a determination that 3 recycling processes produce PET or PEN of suitable purity for 
food-contact use, FDA no longer recommends that such recyclers submit data for agency 
evaluation.  Because 3 processes for polymers other than PET and PEN were not the subject of 
FDA reviews, recyclers who wish to engage in 3 recycling of polymers other than PET and 
PEN are encouraged to submit data for evaluation.  Please send submissions to the Office of 
Food Additive Safety (OFAS) at the address given on the cover of this guidance. 
 
Appendix 1. Model of the Sorption of Surrogate Contaminants into 
Plastic  
FDA recommends using the following equation from Crank (1975) to model the sorption, at a 
fixed temperature, of any substance (including surrogate contaminants) into plastic: 
 
           (1) 
                  (2) 
 
In this equation, M and M  are, respectively, the sorption (g surrogate/g plastic) at time t and the 
t 
sorption at equilibrium (or infinite time),  is the ratio of the volume of the surrogate solution 
to the volume of the plastic, D is the diffusion coefficient (cm2/s) of the surrogate in the plastic at 
a given temperature, t is the time in seconds, and l is the thickness of the plastic (cm).  The full 
thickness is used for a single-sided experiment (i.e., a plastic bottle filled with surrogate solution) 
16 
  Contains Nonbinding Recommendations 
while half the thickness is used for a double-sided experiment (i.e., a plastic strip soaked in a 
surrogate solution). 
 
To solve Eqn. 1 for M, a value for M  is needed.  In the absence of experimentally determined 
t 
values, FDA recommends using the following equation derived from Crank (1975) to calculate 
M : 

 
                  (3) 
 
In this equation, a is the volume of the surrogate solution (milliliter (mL)), w is the mass of the 
polymer (g), and C  is the starting concentration of the surrogate in the solution (g/mL). FDA's 
o
version of this equation differs from Crank's in that the mass of the polymer is included in the 
denominator to obtain M  in the units g surrogate/g plastic. 

 
The following parameters were used for a typical non-food PET bottle:  a 1-liter (L) capacity, a 
mass of 38.26 g, a density of 1.37 g/cubic centimeter (cm3), and a wall thickness of 0.03 cm.  
The bottles mass was divided by its density to obtain the volume of PET in contact with the 
surrogate solution.  A 10% w/w concentration of each surrogate in solution was assumed to 
represent the maximum concentration of any given component of a non-food substance packaged 
in PET.[4]  The densities of the surrogate and the remainder of the surrogate solution (assumed 
to be 1 g/cm3) were used to calculate C.  The following diffusion coefficients were used for 
several surrogates in PET: 
 
D (cm2/s), 
Surrogate  25C  Reference 
Chloroform  9.1 x 10-14  Calculated with Piringer model (Baner et 
al., 1996) 
Toluene  4.3 x 10-15  Sadler et al., 1996 
Benzophenone  4.8 x 10-14  Calculated with Piringer model (Baner et 
al., 1996) 
Lindane  1.6 x 10-14  Calculated with Piringer model (Baner et 
al., 1996) 
Tetracosane  1 x 10-16  Sadler et al., 1996 
 
To validate the model, the modeled results were compared with experimental measurements of 
toluene sorption into a PET strip (i.e., a two-sided experiment) made by Demertzis et al. (1997) 
after 15 and 40 days at 40C.  Sadlers D value of 3.92 x 10-14 square centimeters (cm2)/second 
(s) for toluene at 40C, which has been well characterized, was used in the model (Sadler et 
17 
  Contains Nonbinding Recommendations 
al., 1996). Specifications for the PET strip and the surrogate solution as given in the Demertzis 
article were also used.  The results follow: 
 
Time  Modeled Toluene  Experimentally Measured Toluene 
(days) at  Sorption from 16.7%  Sorption from 16.7% (w/w) Soln. 
40C  (w/w) Soln.  (Demertzis et al., 1997) 
15  3.1 mg/square decimeter  3.5 mg/dm2 of PET 
(dm2)of PET 
(750 mg/kg in PET) 
40  5.1 mg/dm2 of PET  6.0 mg/dm2 of PET 
(1230 mg/kg in PET) 
 
The excellent agreement of the modeled results with experimental measurements indicates that 
the model adequately predicts surrogate sorption into PET over time.  However, the model tends 
to overpredict sorption when experimentally determined D or M  values are not available and 

semi-empirical or theoretical values are used.  The Piringer model, an empirical correlation 
based on the molecular weight of the migrant, was used to calculate D for chloroform, 
benzophenone, and lindane for input to the sorption model (see Baner et al., 1996).  
Comparisons of modeled D values with experimental measurements indicate that the Piringer 
model can overestimate D by several orders of magnitude (Baner et al., 1996).  This discrepancy 
was attributed to failure of the model to account for partitioning of the migrant between the 
solvent and polymer phases.  Similarly, Eqn. 3 will generally overpredict M  because it does not 

take into account partitioning of the migrant between the solvent and polymer phases 
(Crank, 1975).  Because the sorption model depends on D and M , overestimates of these values 

will result in overestimates of sorption.  Modeled results for a typical bottle are given in Table 3: 
 
Table 3. Modeled Sorption of Surrogates into 1-L PET Bottles Filled with 10% w/w 
Surrogate Solutions after 365 days at 25C 
 
Surrogate  Modeled Sorption into PET, mg/kg 
Chloroform  4860 
Toluene  1000 
Benzophenone  3390 
Lindane  1920 
Tetracosane  154 
 
FDA believes that the modeled sorption value for chloroform is probably reasonable because 
there is very little partitioning of chloroform between the solvent and polymer phases.  However, 
18 
  Contains Nonbinding Recommendations 
the measured sorption values for benzophenone and lindane show the modeled values to be 
significant overestimates due to the need to rely on semi-empirical or theoretical 
D and M  values (Begley et al., 2002). 

 
IX. Paperwork Reduction Act of 1995 
This guidance contains information collections that are subject to review by the Office of 
Management and Budget (OMB) under the Paperwork Reduction Act of 1995 (44 U.S.C. 3501-
3521).   
 
The time required to complete this information collection is estimated to average 25 hours per 
response, including the time to review instructions, search existing data resources, gather the data 
needed, and complete and review the information collection.  Send comments regarding this 
burden estimate or suggestions for reducing this burden to: 
 
Office of Food Additive Safety 
Division of Food Contact Substances, HFS-275 
Center for Food Safety and Applied Nutrition 
Food and Drug Administration 
5001 Campus Drive 
College Park, MD 20740 
 
An agency may not conduct or sponsor, and a person is not required to respond to, a 
collection of information unless it displays a currently valid OMB control number.  
The OMB control number for this information collection is 0910-0495 (To find the 
current expiration date, search for this OMB control no. available at 
https://www.reginfo.gov/public/do/PRAMain). 
 
 
The above guidance document supersedes the previous version dated August 2006. 
 
X.  References   
The following references marked with an asterisk (*) are on display at the Dockets Management 
Staff, (HFA-305), Food and Drug Administration, 5630 Fishers Lane, Rm. 1061, Rockville, MD 
20852, 240-402-7500 and are available for viewing by interested persons between 9 a.m. and 4 
p.m., Monday through Friday; they are also available electronically at 
https://www.regulations.gov.  References without asterisks are not on public display at 
https://www.regulations.gov because they have copyright restriction.  Some may be available at 
the website address, if listed.  References without asterisks are available for viewing only at the 
Dockets Management Staff.  FDA has verified the website addresses, as of the date this 
document publishes, but websites are subject to change over time. 
 
1.  Adding Custom PET Bottles Helps Increase Plastics Recycling. April 16, 1996. Waste 
Age's Recycling Times, p. 7. 
19 
  Contains Nonbinding Recommendations 
 
2.  Baner, A., Brandsch, J., Franz, R., and Piringer, O. 1996. The Application of a Predictive 
Migration Model for Evaluating the Compliance of Plastic Materials with European Food 
Regulations, Food Additives and Contaminants, 13 (5), pp. 587-601. 
 
3.  Begley, T.H., McNeal, T.P., Biles, J.E., and Paquette, K.E. January 2002. Evaluating the 
Potential for Recycling All PET Bottles into New Food Packaging, Food Additives and 
Contaminants, 19 (1), Supp. 1, pp. 135-143. 
 
4.  Crank, J. 1975. The Mathematics of Diffusion, 2nd Edition, Oxford:  Clarendon Press, pp. 56-
59, Equations No. 4.43, 4.41. 
 
5.  Demertzis, P.G., Johansson, F., Lievens, C., and Franz, R. 1997. Development of a Quick 
Inertness Test Procedure for Multi-Use PET Containers  Sorption Behavior of Bottle Wall 
Strips, Packaging Technology and Science, 10, pp. 45-58. 
 
6.  U.S. Environmental Protection Agency. November 1994. Characterization of Municipal 
Solid Waste in the United States: 1994 Update, EPA/530-S-94-042, Washington, DC  20460, 
Table 7.  Available at: 
https://nepis.epa.gov/Exe/ZyPDF.cgi/1000176V.PDF?Dockey=1000176V.PDF.* 
 
7.  U.S. Environmental Protection Agency. 1999. Municipal Solid Waste in the United States: 
1999 Final Report, Washington, DC  20460, Table 7  Available at: 
https://web.archive.org/web/20061008184218/http:/www.epa.gov/epaoswer/non-
hw/muncpl/pubs/99tables.pdf.*  
 
8.  Komolprasert, V., and Lawson,  A. 1995. Residual Contaminants in Recycled Poly(ethylene 
terephthalate):  Effects of Washing and Drying in Plastics, Rubber and Paper Recycling:  A 
Pragmatic Approach, Ch. 35, ACS Symposium Series 609, pp. 435-444. 
 
9.  PET Finds Growing Use in Non-Food Containers. April 1997. Modern Plastics, pp. 60-65. 
 
10. Piringer, O., Franz, R., Huber, M., Begley, T.H., and McNeal, T.P. 1998. Migration from 
Food Packaging Containing a Functional Barrier:  Mathematical and Experimental 
Evaluation, Journal of Agricultural and Food Chemistry, 46 (4), pp. 1532-1538. 
 
11. Plastics Market Analysis. April 1996. Plastics Recycling Update, p. 1. 
 
12. Sadler, G., Pierce, D., Lawson, A., Suvannunt, D., and Senthil, V. 1996. Evaluating Organic 
Compound Migration in Poly(ethylene terephthalate):  A Simple Test with Implications for 
Polymer Recycling, Food Additives and Contaminants, 13 (8), pp. 979-989. 
 
Document History 
  August 2006  First edition of guidance was issued. 
20 
  Contains Nonbinding Recommendations 
  July 2021  The guidance was updated to include Paperwork Reduction Act information 
and non-substantive formatting or editorial revisions.  
Endnotes 
[1] FDA will assume a default CF of 0.05 for any recycled polymer.  Previously, FDA used a CF 
for both virgin and recycled PET of 0.05.  Based on recent market data that demonstrated that, 
since 1990, virgin PET has captured a dramatically larger share of the food-packaging market, 
FDA increased the CF for virgin PET to 0.16.  Such an increase in market share has not been 
observed for recycled PET, so FDA uses a CF for recycled PET of 0.05.  Because PET is 
recycled into food containers at a higher rate than any other polymer, it can be assumed that the 
CF for any other recycled polymer will not exceed 0.05. 
 
[2] Although FDA previously recommended testing with a polymer-specific surrogate, e.g., 
ortho-cresol, which is known to significantly swell PET, such data are no longer considered 
necessary because: 1) the range of possible contaminant properties are already covered by the 
five surrogate categories selected, and 2) a consumer's storage of a polymer-specific solvent in a 
bottle would significantly degrade the bottle to the extent that it would be rejected during the 
sorting process. 
 
[3] Of 280,000 tons of custom PET containers generated in 1993, 3.6% was recycled.  Of 
820,000 tons generated in 1999, 9.8% was recycled. See EPA, 1994, and EPA, 1999, under the 
Other plastic containers entries for PET. 
 
[4] A search of a database of ingredients in household products (http://www.happi.com) shows 
that liquid detergents, shampoos, and hand cleaners might contain up to 30% long-chain fatty 
acids; however, these compounds are not expected to sorb into PET to any greater extent than 
lower molecular weight compounds from 10% solutions. 
21