News from NZFSSRC

Should food and recycled packaging go together?

This article has been written exclusively for FoodNZ magazine by the NZ Food Safety Science and Research Centre

The urgent shift to a so-called circular economy, which does away with waste, presents many opportunities and challenges for the food industry. We know it’s the right thing to do, but it’s hard and it’s complicated. The NZ Food Safety Science and Research Centre (NZFSSRC) is fast trying to get to grips with the food safety risks that may emerge from the use of recycled plastic and paper/cardboard packaging.

Pressure on the food industry

Pressure is converging on the food industry from all sides to replace, at least in part, "virgin" packaging with recycled/sustainable alternatives. Global, national and local regulations and targets to reduce and recycle plastics have alarmingly tight timeframes. For example, Australia has set these ambitious targets which exporters to one of our biggest markets should heed:

• 100% of packaging being reusable, recyclable or compostable by 2025

• 70% of plastic packaging being recycled or composted by 2025

• 50% of average recycled content included in packaging by 2025

UK and EU countries have different targets and timeframes, with the EU currently considering submissions on regulations which will facilitate the adoption of new and, at least initially, potentially unvalidated recycling technologies.1

Food safety vs protecting the environment?

But are such targets feasible for the food industry, where the safety and integrity of product is all important? Is there a fundamental conflict between protecting human health and protecting the environment?

The NZFSSRC has a very effective and collegial industry advisory group representing the main food sectors. They initiated and co-funded, with government chipping in 40%, a research project to help New Zealand companies understand the safety implications of using recycled plastics, paper and cardboard. Acting Director of NZFSSRC, Professor Phil Bremer, Associate Professors Miranda Mirosa and Pat Silcock (University of Otago), and Professors Paul Kilmartin and Brent Young (University of Auckland), joined forces to cover different aspects. Bremer and Mirosa have been surveying the data, interviewing New Zealand companies about their particular needs, and mapping recyclable/reusable/compostable packaging alternatives and their suppliers, both here and overseas. Kilmartin and colleagues are meanwhile identifying the chemicals likely to be present in recycled packaging, assessing the potential for them to migrate onto food, and the attendant risks to human health. Silcock is studying packaging-food interactions which might taint the food, and reduce quality and shelf life. Their guidelines are due for release around the time this article appears, so watch out for their report on www.nzfssrc.org.nz if you are not already a member of the NZFSSRC. The next obvious step, says Bremer, is to home in on the risks for individual product categories and companies.

What are the concerns about recycled packaging?

An estimated 600 authorised additives are variously added to first generation plastic. Plasticisers, UV blockers, flame retardants, stabilisers, fragrances, biocides, antioxidants and colourants are used to design a myriad of useful products. In some cases, the additives account for over half the mass. FSANZ has well-researched and managed regulations regarding additives in food packaging. The problem with virgin product is more about the environment than a food safety issue. Discarded, it ends up on land and at sea, or accumulates for near eternity in our landfills, gradually leaching additives into soil and water, which can then find their way into animals, including humans and fish. ESR is researching the impact of environmental microplastics. Single-use plastic now seems like unimaginable stupidity that will shock future generations. When plastics from a variety of unstreamed sources – a large fraction of it not food grade – are recycled, indeterminant levels of these additives remain, and further amounts of some must be added to ensure the desired functionality in the next generation of materials, depending on its use.

Of additional concern with recycled packaging are the other chemicals that may be present unintentionally (NIAS = non intentionally added substances) – picked up in the waste stream, from the environment, or previous use of the packaging. As well as not knowing what has got into the recycling mix, the risk to human health of many chemicals is unknown, and until it is, regulators will take a conservative approach when it comes to potential human toxicity. Unless removed, unwanted substances may persist, and even concentrate, in successive generations of recycling. As well as the challenges of finding safe, suitable and sustainable alternative forms of packaging, food and drink manufacturers have to navigate all the different regulations in countries we export to. Pushing back against the recycling imperatives are these measures:

• US and European regulations require the same level of safety for recycled as for virgin materials.

• FDA considers recycling processes for food contact containers on a case-by-case basis.

• Switzerland has banned the use of recycled paper and board in direct contact with food.

• In several EU member states the food packaging chain has been called on to take measures to reduce levels of mineral oil hydrocarbons in foodstuffs (these contaminants can get onto food from processing equipment, and are ubiquitous in the environment).

• In 2017, the European Commission issued a recommendation on the monitoring of mineral oil hydrocarbons in food and in materials and articles intended to come into contact with food.

Safety levels with chemicals are a hard sell, no matter how conservative. Consumers and regulators really don’t want any contaminants present at all. As improving technologies are able to detect chemicals at lower and lower concentrations, regulators and consumers may become increasingly risk averse. So, for example, even though the effects of BPAs, (bisphenol A), a widely used additive which gives backbone to plastics but can disrupt hormones in humans and other animals, has been exhaustively studied in the US, and shown to be well under safety limits in packaging and food, consumer and media reaction was such that many manufacturers have removed it from their packaging, and used that as a selling point.

Persistent chemicals

In a recent NZFSSRC webinar on emerging food contaminants, (Visit www.nzfssrc.org.nz/events to view) Dr Andrew Pearson, senior environmental consultant with Tonkin & Taylor and member of a WHO/FAO committee on food additives, focused on two groups of chemicals widely used in plastics, which are concerning because of their persistence in the environment and likely uptake by humans and other animals. Their toxicity is as yet unknown, but it is generally agreed that anything that does not biodegrade and accumulates in the body, is not a good thing.

One is a group of fluorinated compounds called PFAS for short, dubbed "forever chemicals". They have been used widely as moisture barriers – their dislike of water is their principal virtue – for example in pizza box interiors and microwave popcorn packets. The Ministry for the Environment led an "all of government response" to assess and deal with potential PFAS contamination of land and groundwater around the country.2 Fluorinated firefighting foams are a known source. The report said, “Testing at a number of sites has shown the presence of PFAS compounds above interim guidance levels adopted by the Ministry of Health. Government agencies and regional councils are working to fully understand the extent and possible impact of the problem.” However the Ministry for Primary Industries (MPI) advised that “there is no risk to the general food supply from produce grown on properties that have been sampled.”

There are over 12,000 compounds in the PFAS family. They comprise a string of carbon atoms bonded to fluorine atoms, with a variety of other atoms and molecules added on one end, which confer their individual characteristics. The toughly bonded carbon-fluorine chains are virtually indestructible in the environment. Pearson says that although the long chain ones are being phased out and the UNEP Stockholm Convention has condemned several as POPs (persistent organic pollutant), the short chain ones are still widely in use and can be much more mobile in the environment. They have been reported in soil, compost, wastewater and food. Unless we start screening them out and incinerating them, they will remain and accumulate in the closed recycling loop. Pearson cited a Massey University survey which found them in 100% of its human subjects.

A study of packaging in the US market found that one of the PFAS family, PFHxA, exists in 46% of food contact papers and cardboard. PFHxA was the only PFAS found in a 2018 MPI food survey. The smaller molecules, such as PFHxA, can more easily get into food crops via compost and water.

As water security becomes more of an issue because of climate change, there will be incentives to use grey water for irrigation, and this may pose problems with chemicals (pharmaceuticals, cosmetics, washing detergents, agricultural chemicals) entering the food chain.

Analytical chemist, Dr Tim Harwood, Deputy Director of the NZFSSRC, says sea creatures are at the mercy of whatever washes out of our rivers and streams so vigilance is needed to help protect our valuable seafood resources.

Under an MBIE project to investigate emerging organic (meaning carbon-based) contaminants, eco-toxicologist at the Cawthron Institute and the University of Auckland, Dr Louis Tremblay, has been surveying the chemicals in water at two contrasting river sites – one in industrial Auckland, the other in Southland – traversing a mix of agricultural land, light industry and residential areas. His team deployed devices along the rivers, designed to capture different types of chemical contaminants. The work included the exact identification of the chemicals and assessment of their toxicity to various marine biota. One method they used exposed successive generations of little creatures called copepods, to see how the chemicals affected gene expression over time.

This brief explanation slides over some very advanced and ingenious chemical and biological analyses. For more detail, see the presentation at www.nzfssrc.org.nz/events. Tremblay says his ultimate goal is to reach a point where chemicals are better managed so eco-toxicologists are no longer needed.

The Parliamentary Commissioner for the Environment, Simon Upton, and his team, have just released a report about the effectiveness of current regulations to manage the fate of chemicals and whether there is sufficient information on the environmental consequences/risks. The report identified data gaps on the releases of chemical contaminants into the environment and suggested the introduction of a Pollutant Release and Transfer Register (PRTR) framework as a partial solution.3

Tremblay reports that BPA is one of the key plastic-derived contaminants in the water. Its presence may be negligible in our food, but it is commonly detected in our fresh and sea water where it could disrupt the fertility of fish. The second persistent organic pollutant Pearson drew attention to is another common plastic constituent, UV-328, which blocks damaging UV rays and accounts for up to 0.1 to 1.0% of its mass. It also accumulates in humans, fish, and seabirds, but its toxicity is currently unknown.

Of course, the simple way to ensure that recycled packaging does not contaminate food, is to make sure it does not come into direct contact with it. The big plastics recycling plant in Seaview, Lower Hutt, sandwiches recycled plastics between virgin sheets, which become the inner and outer layers. They form the sheets into customised retail packs for berries, muffins, meat packs, and so on. Likewise, cardboard boxes can be lined, and papers waxed. But this limited use is going to make meeting the recycled content goals difficult.

Solutions will be found

Pearson reminds us that recycling is just one approach on the journey to the top of the circular economy ladder, with effort also being put into reducing and reusing packaging. “It might seem like an impossible goal, but there’s a lot of clever thinking going into the science at NZFSSRC, Universities, and CRIs like Scion and Plant & Food. And the government is moving ahead with plans to standardise kerbside recycling, separate food and other biological waste from general waste and recycling, and start a return scheme on drink containers." 4 We all have to be positive, and just get on with it,” says Bremer. “I’m impressed with the ‘can do’ attitude in the industry.”

Notes and links

1. https://zerowasteeurope.eu/wp-content/uploads/2022/02/Feb2022_ Open-Letter-Recycled-Plastics-in-Food-Packaging.pdf https://ec.europa.eu/info/law/better-regulation/have-your-say/ initiatives/12013-Food-safety-recycled-plastic-in-food-packagingupdated-rules-_en 2. https://environment.govt.nz/what-government-is-doing/ areas-of-work/land/per-and-poly-fluoroalkyl-substances-pfas/ information/#what-is-the-risk-from-consuming-foods-from-affectedproperties 3. https://www.pce.parliament.nz/media/197185/regulating-theenvironmental-fate-of-chemicals.pdf 4.https://www.beehive.govt.nz/release/government-plans-transformrecycling