‘Safer’ PFAS replacements in food packaging still hazardous, finds research: ‘Polymers aren’t a harmless loophole’
PFAS (per- and polyfluoroalkyl substances) are attracting attention for all the wrong reasons. The ‘forever chemicals’ – so-called because the group of 4,700 manmade chemicals bioaccumulate in the environment – are used in some food packaging, non-stick cookware, clothing, and in products that resist grease, water, and oil.
Although ingestion of PFAS is not expected to make one acutely ill, health risks increase if significant quantities are consumed over an extended period. Ingestion risk, coupled with the fact that PFAS do not degrade in the environment, puts PFAS in the firing line.
The EU’s European Chemicals Agency (ECHA) has responded with a proposed restriction of around 10,000 PFAS, with the aim of reducing PFAS emissions into the environment while making products and processes safer for people.
In the meantime, some food packaging companies are pivoting towards larger polymeric PFAS to make their wrappers, bowls, and other fast-food packaging water- and grease-repellent. But fresh research out of North America suggests polymeric PFAS-based food packaging is still hazardous.
PFAS in the headlines
PFAS recently made headlines when they were identified in organic eggs in Denmark. It is understood the so-called forever chemical contaminated the fishmeal consumed by the egg-laying hens.
Trade association European Fishmeal and Fish Oil Producers (EFFOP) told us environmental contamination is a possibility in fishmeal, with human activity the main source of this contamination. “We believe the chemicals are discharged into the sea from industrial production,” Dr James Hinchcliff from Marine Ingredients Denmark and EFFOP told FoodNavigator.
Are polymer PFAS safe for humans and the environment?
Polymeric PFAS have been promoted as safer alternatives by the plastics industry, which claims fluoropolymers, for example, are inert and too heavy to escape from products.
According to Plastics Europe, fluoropolymers meet the OECD criteria for polymers of low concern. “They are chemically and biologically stable, non-bio accumulative, and non-toxic,” noted Nicolas Robin, director of the fluoropolymers product group at Plastics Europe, in a communication last year.
It is a ‘myth’, according to the membership organisation, that as a subset of the PFAS family, fluoropolymers are bio accumulative. “Some small molecular PFAS chemicals have been shown to bioaccumulate in animals, but fluoropolymers do not share this characteristic because of their extremely large molecules.
“Fluoropolymers do not break down into small PFAS molecules in the environment. They are stable in air, water, sunlight, chemical and microbial environments.”
Plastics Europe also sought to debunk the myth that fluoropolymers are mobile in the environment and hazardous to the environment and humans. “Fluoropolymers have a unique combination of physiochemical properties that set them apart from other PFAS. They are chemically and biologically inert and, under recommended operating conditions, they do not break down into harmful chemicals,” noted Robin.
But just under one year later, the ‘first evidence’ that polymeric PFAS used in food packaging break down into smaller molecules that are still harmful and can leach into food and environment has come to light.
“It’s clear that polymers aren’t the harmless loophole the PFAS industry was counting on them to be,” said Marta Venier, co-author and professor at Indiana University. “Their use in food packaging still leads to harmful and persistent PFAS contaminating the food we eat, and after it’s thrown away, our air and drinking water.”
Plastics Europe did not immediately respond to a request for comment.
‘Polymeric PFAS are mobile and create exposure risks’
To arrive at these findings, researchers from the US, Canada, and Switzerland tested 42 paper-based wrappers and bowls collected from fast food restaurants in Toronto. The most abundant compound detected in these samples was the toxic PFAS 6:2 fluorotelomer alcohol.
The researchers say the polymeric PFAS in the samples can transform into this compound, thereby adding to a consumer’s exposure to it.
In what they believe contradicts claims that polymeric PFAS are immobile and do not create exposure risks, the researchers found that the concentration of PFAS declined by up to 85% after storing the products for two years under normal conditions (at room temperature and in the dark). They note that much of these losses were consistent with the breakdown of the polymeric PFAS added to the fast food packaging.
As to the toxicity of all PFAS, only a ‘small fraction’ of the thousands that exist have been tested. But all PFAS, including polymers, are either ‘extremely’ persistent in the environment or break down into extremely persistent PFAS, according to researchers from Indiana University.
Is a PFAS ban on the cards for Europe?
In the US, regulators have expressed concerns over PFAS content in food packaging. To date, 11 US states have banned PFAS from most food packaging and some fast food companies – including McDonalds and Chick-fil-A – have committed to eliminating PFAS from their operations by 2025.
Whether PFAS bans go far enough is up for debate. In the US, the ecological health-focused Green Science Policy Institute praises the ‘great progress’ towards phasing out PFAS, polymers included, from fast food packaging. “However, this study calls into question the safety of polymeric PFAS for many of its uses.
“The best course of action to protect our children and future generations is to eliminate the whole class of PFAS from all non-essential uses, from food packaging to rain jackets, as soon as possible,” said institute executive director Arlene Blum who co-authored the study.
Meanwhile in Europe, authorities in Denmark, Germany, the Netherlands, Norway and Sweden are calling for PFAS restrictions. In a business-as-usual scenario, they estimate around 4.4m tonnes of PFAS would end up in the environment over the next 30 years.
“This landmark proposal by the five authorities supports the ambitions of the EU’s Chemicals Strategy and the Zero Pollution action plan. Now, our scientific committees will start their evaluation and opinion forming,” noted ECHA director for risk assessment Peter van der Zandt.
“While the evaluation of such a broad proposal with thousand of substances, and many uses will be challenging, we are ready.”
Last month ECHA launched a six-month consultation on the restriction process, calling for information relevant to the risks, socio-economic aspects, and alternative substances.
Source: Environmental Science & Technology Letters
‘Per- and Polyfluoroalkyl Substances in Canadian Fast Food Packaging’
Published 28 March 2023
DOI: https://doi.org/10.1021/acs.estlett.2c00926
Authors: Heather Schwartz-Narbonne, Chunjie Xia, Anna Shalin, Miriam L. Diamond et al.
