In March 2021, a research team led by Gregory Glenn from the US Department of Agriculture (USDA) published a review article in the journal Comprehensive Reviews in Food Science and Food Safety on alternatives for per- and polyfluoroalkyl substances (PFAS) in paper food packaging. In their article, the authors describe the availability, suitability, and limitations of currently discussed alternatives for PFAS. A very common strategy identified includes adding waxes or lamination of paper with polymer films such as polyethylene (PE; CAS 9002-88-4), poly(ethylene‐co‐vinyl alcohol) (CAS 25067-34-9), and polyethylene terephthalate (PET; CAS 25038-59-9).
However, these laminates and waxes are neither biodegradable nor recyclable. Laminates with biodegradable polymers are discussed as well, such as poly-lactic acid (PLA; CAS 26100-51-6), polybutylene adipate terephthalate (PBAT; CAS 60961-73-1), polybutylene succinate (PBS; CAS 25777-14-4), and polyhydroxyalkanoates (PHA). In addition to laminates, surface sizing and coatings with materials such as starch (CAS 9005-25-8), plant protein, and chitosan (CAS 9012-76-4) represent other processing techniques that can provide “adequate oil barrier properties but have poor moisture resistance without chemical modification.”
The authors emphasize the difficulties in finding a suitable replacement for PFAS chemicals, which will require more research efforts: “Numerous nontoxic chemicals with various processing methods have been proposed to replace PFAS [..] but a cost-effective, fully biodegradable, and environmentally friendly replacement which can be easily processed to attain the effectiveness of PFAS has remained elusive so far.”
PFAS have been ubiquitously applied in paper food packaging due to adding high water and grease resistance properties. However, exposure to PFAS such as perfluorooctanoic acid (PFOA; CAS 335-67-1) poses a health risk to humans, therefore, this group of chemicals has been facing stricter regulation by governments and gradual phase-out from food packaging by big retailing companies such as Amazon (FPF reported) and McDonald’s (FPF reported). In February 2021, the Department of Ecology (DoE) of the US state of Washington published an Alternatives Assessment identifying safer alternatives to replace PFAS in wraps and liners, plates, and pizza boxes (FPF reported).
Glenn et al. (March 2021). “Per‐ and polyfluoroalkyl substances and their alternatives in paper food packaging.” Comprehensive Reviews in Food Science and Food Safety
Department of Ecology (February 2021). “Per- and Polyfluoroalkyl Substances in Food Packaging Alternatives Assessment.”