Tom Neltner, Chemicals Policy Director; Maricel Maffini, consultant; and Tom Bruton with Green Science Policy Institute
Since 2002, FDA has authorized the use of four types of per- and polyfluorinated alkyl substances (PFAS) to make plastic food packaging, one as recently as 2016. The PFAS are allowed in plastic at levels up to 2000 parts per million (ppm); although lower than those used to greaseproof paper, these levels still contaminate food. The PFAS are added to facilitate the production of articles such as bottles and wraps. They reportedly improve polymer extrusion, reduce build-up on the injection mold, and improve surface roughness among other technical effects.
EDF submitted a Freedom of Information Act (FOIA) request for seven food contact substance notices (FCNs) that FDA has authorized. From FDA’s response[1], we learned that these PFAS can contaminate food in contact with the packaging. In one case the overall amount of the PFAS in the diet would be as high as 41 ppb (see pages 31-32 of FOIA response) – much more than is tolerated for some PFAS in drinking water.
These plastic processing aids, along with fluorinated polyethylene, are the latest additions to a growing list of sources of ‘forever chemicals’ in the diet. They join environmental contamination and greaseproofed paper and cardboard as sources that food companies must consider in order to keep PFAS out of their products and respond to consumer demand for safer food. Given the evidence, FDA needs to move forward pursuant to our June 2021 citizens petition to evaluate the safety of PFAS taking into account the cumulative effect of these chemicals in the diet from many sources.
FDA authorized seven PFAS uses in plastic from 2002 to 2016
FDA describes the PFAS uses in the seven FCNs as processing aids because they do not serve a purpose in the final packaging. Even though they are used only to facilitate manufacturing of the food contact article, some of the PFAS stay in the plastic, where they migrate into food. FDA states that “the amount of PFAS used as processing aids in the manufacture of other food contact polymers is so small that a negligible amount of PFAS is capable of migrating to food from this use.”
The table below shows the amount of PFAS authorized to be added to plastic in food packaging and processing equipment. They are not “so small,” considering that they add to the burden of PFAS already present in our food, our bodies, and the environment.
Authorized food contact substance notifications (FCN) for PFAS uses as processing aid in plastic food packaging
| FCN # | Food Contact Substance | Intended use | Limitation | Dietary concentration |
|---|---|---|---|---|
| 1601 Daikin (March 2016) | 2,3,3,4,4,5,5-Heptafluoro-1-pentene polymer with ethene and tetrafluoroethene (CAS Reg. No. 94228-79-2) | For the property improvement in extrusion process of all polymers for food packaging, except for use in contact with infant formula and breast milk | The FCS is intended to be used at levels up to 2000 ppm in all polymers that contact all food | 9 ppb LMWO*; 0.004 ppb of 2,3,3,4,4,5,5-heptafluoro-1-pentene |
| 1560 Arkema (Sept. 2015) | Vinylidene fluoride-hexafluoropropene copolymer (CAS Reg. No. 9011-17-0) | As a processing aid for food contact polymers, except for use in contact with infant formula and breast milk | For use at levels not to exceed 2000 ppm in all polymers | 2.08 ppb of LMWO |
| 1448 Arkema (Aug. 2014) | Vinylidene fluoride-hexafluoropropene copolymer (CAS Reg. No. 9011-17-0) | As a processing aid for food contact polymers, except for use in contact with infant formula and breast milk | For use at levels not to exceed 2000 ppm in all polymers | 41.6 ppb of LMWO |
| 1255 3M (April 2013) | Vinylidene fluoride-hexafluoropropene copolymer (CAS Reg. No. 9011-17-0) | As a processing aid in all polymers (excluding polymers used in metal and paper coatings) | The FCS may be used at a maximum level of 2000 ppm by weight of the finished polymer | Information was redacted |
| 1121 3M (January 2012) | Tetrafluoroethylene-hexafluoropropylene-vinylidene fluoride copolymers (CAS Reg. No 25190-89-0) | As a processing aid in all polymers (excluding polymers used in metal and paper coatings) | The FCS may be used at levels up to 2000 ppm in food-contact polymers | 0.37 ppb of LMWO |
| 736 Dyneon / 3M (Oct. 2007) | 1-Propene,1,1,2,3,3,3-hexafluoro-, polymer with 1,1-difluoroethene (CAS Reg. No. 9011-17-0) modified with a halogenated ethylene as described in the food contact notification | As a processing additive for all polymers for use in contact with food | The FCS may be used at levels up to 1000 ppm in the finished polymer. | 0.4 ppb of LMWO |
| 260 Dyneon / 3M (Oct. 2002) | Tetrafluoroethylene-hexafluoropropylene-vinylidene fluoride copolymers (CAS Reg. No. 25190-89-0) | As a processing additive for polyolefins for use in contact with food. | The FCS may be used at levels up to 2000 ppm in food-contact polyolefin | 0.07 ppb of LMWO |
| * LMWO: low molecular weight oligomers. FDA typically defines LMWOs as those below 1000 Daltons (a measure of molecular weight with hydrogen as one). However, it treats fluorinated compounds as an exception that raises the limit on 2500 Daltons. | ||||
FDA underestimates the exposure and ignores the cumulative effect of PFAS
For each of the authorized uses, FDA calculated the amount of PFAS that would be in an adult’s diet of 3 kilograms of food and beverages a day, estimating levels that ranged from 0.07 to 41.6 ppb. FDA typically describes this number as a “worst case” estimate because they assume the PFAS is used in all allowed final plastic packaging and migrates at the maximum rate. However, this is not necessarily true because the agency ignored migration from PFAS containing plastic used to store, process, and transport the raw materials and ingredients.
In addition, the safety assessments by the notifier and FDA did not appear to take into account the cumulative effects of the many other related PFAS also in the diet from intentional use in contact with food or environmental contamination. Once again, FDA did not follow the law and its regulation stating that the safety of substances with similar toxicological effect should be assessed as a class rather than one individual substance at the time. This is the case with virtually all of its decisions, but is especially significant for PFAS since some bioaccumulate in the human body. In September 2020, EDF and others have petition the agency to upgrade its science to consider cumulative effects to protect consumers as Congress intended.
Processing aids are intentional uses
FDA authorized the use of PFAS as a processing aid to facilitate the manufacturing of plastic food contact articles. The agency reviews the safety of these substances as intentional uses because they are substances “the intended use of which results or may reasonably be expected to result, directly or indirectly, in their becoming a component of food” thus meeting the definition of food additive (21 U.S.C. § 321(s)).
Despite companies asserting that PFAS processing aids are not intentionally added, it is clear that to FDA they are.
Steps forward to protect us from “forever chemicals”
In 2018, FDA recognized that it had to address heavy metals contamination “looking at all the metals across all foods rather than one contaminant, one food at a time” because “[e]ven though the levels of a metal in any particular food is low, our overall exposure adds up because many of the foods we eat contain them in small amounts.”
Just like heavy metals, there are many sources of PFAS contamination, multiple PFAS are present in the diet at low levels, and the overall exposure adds up quickly because of the known bioaccumulation of some PFAS which exacerbates their toxicity and health risk. While FDA has been focused on PFAS contamination from the environment and its use in paper packaging, it has been allowing PFAS-laden plastic to also contaminate the food supply without considering the cumulative effect of their dietary exposure on people’s health. It’s time for FDA to take a comprehensive approach to reassess the safety of all uses of PFAS because there are no ‘negligible’ levels of exposure when it comes to ‘forever chemicals.’
Updated on August 14, 2021 to correct number of unique PFAS authorized from three to four.
[1] We are only posting the agency’s toxicology and chemistry memo. Contact authors for full FOIAs.