Know Your Materials

Safer Foodservice Packaging Materials

Some coatings used to make paper-based foodservice packaging grease-resistant carry known health risks. Here’s a way to eliminate those—and keep the packaging a recyclable material that’s affordable.

For a long time, food-contact fiber packaging used in foodservice for bags, paper wrappings, paperboard trays, and so on, has been treated to protect it from grease.

As seen on CNN and CBS News, it turns out that consumers now need protection from the packaging.

Making food service packaging moisture and grease-resistant is an aesthetic imperative for foods with moisture and fat content such as doughnuts, cake slices, sandwiches, french fries, and pizza. Seeing big grease spots on the wrapping or tray can be messy and a turnoff—an unpleasant reminder for consumers of how much fat they’re consuming.

For more than three decades, a frequently-used grease-resistant treatment for paper-based foodservice packaging has consisted of imbuing the fiber with perfluorinated chemicals (PFCs). This is a family of chemicals based on fluorine that helps paper and paperboard resist moisture and grease without unduly altering its appearance or texture.

But beginning in the early 2000s, concerns began to be raised over PFCs and health. Studies have shown that PFCs can migrate from food packaging into the food you eat and if ingested, can remain in the human bloodstream for years and expose consumers to risk of cancer, liver and kidney damage, interference with hormone levels, and other potential health problems.

One of the most widely used PFCs in packaging and other applications was perfluorooctanoic acid (PFOA), the primary chemical component of Teflon. But PFOA became notorious after studies concluded that it was both highly pervasive—by one estimate, 98% of the U.S. adult population carried it in their bloodstreams—and especially toxic. Eventually, the Food and Drug Administration banned PFOA, along with two other PFCs, from food-contact packaging. 3M Corp. stopped making PFOA in 2002; DuPont and other U.S. manufacturers vowed in 2011 to phase out PFOA production entirely.

As PFOA went, the rest of the PFCs seemingly would follow. Although the FDA allows about 20 PFCs to be used for food-contact packaging, several major chains, including McDonald’s and Burger King, have pledged to stop using them.

However, a recent study indicates that PFCs are still widely prevalent in foodservice packaging.

The study, published Feb. 1 in Environmental Science & Technology Letters, was conducted by researchers from institutions including Notre Dame, Berkeley, the Environmental Working Group, the U.S. Environmental Protection Agency and more. It is based on an examination of 400 pieces of packaging—wrappers, cups, and paperboard trays and holders—collected at coffeehouses and fast-food restaurants from 27 chains in five U.S. metro areas, including Starbucks, Dunkin’ Donuts, McDonald’s, and Burger King. Researchers found that 46% of the wrappers and 20% of the paperboard samples had traces of fluorine, the base chemical of PFCs.

The presence of fluorine is not absolute proof that a piece of packaging has been treated with PFCs, but the likelihood is strong, since fluorine does not naturally occur in paper. The researchers followed up by testing 20 of the fluorine-positive samples with a longer, more elaborate procedure that can detect PFCs with certainty. They found that, not only did most of them indeed contain PFCs, but six of them had PFOA, the additive that is supposedly being phased out.

The concern is that, in food-contact packaging like paper wrappers or paperboard clamshells, PFCs will leach into the food. A 2008 FDA study demonstrated that, not only does this happen, but the effect is enhanced by oil and grease—which are disproportionately present in many of the foods packaged in PFC-imbued material. Once fluorine enters the human body, it leaves only gradually; the process can take years.

The study in Environmental Science & Technology Letters shows that foodservice end users can’t depend on the packaging supply sector as a whole to remove PFCs. Short of an absolute ban by the FDA, which isn’t likely, major packaging suppliers will in all likelihood continue to use PFCs for the foreseeable future. If coffeehouses, restaurants and other foodservice venues want packaging free of PFCs, they have to seek it out.

This is certainly possible. Grease-resistant packaging materials have been available for at least 10 years. The problem is that they are not all created equal.

There are non-PFC coatings that are applied like their PFC-containing counterparts, but without the PFC will have inferior performance for grease and oil. To use these coatings, you will have to measure whether a lesser performance is acceptable for a given use.  In the case of fried or baked goods, the barrier performance may not be sufficient. You will also have to be vigilant to ensure that coatings with PFC are not substituted as these coatings are applied in the same manner using the same equipment.

There are packaging materials that can provide the barrier performance without using PFCs.

However, to be an optimal solution, it’s not enough for packaging material simply to be grease-resistant without using PFCs, says Todd Gasparik, director of business development for Smart Planet Technologies. It has to hit what Gasparik calls “the trifecta”: top-notch performance, recyclability, and affordability.

One common alternative for grease resistance is lining the inner surfaces of the packaging with a layer of polyethylene (PE). This is the same method overwhelmingly used in paper cups for coffee and other beverages, to keep the liquid from soaking through the cup. While the PE coating performs well as a barrier, and does not contain PFCs, it fails the recyclability part of the triad. As detailed in the CoffeeTalk article “A Dirty Secret” (March 2017), standard PE coatings make cups and other packaging unrecyclable, because the coating breaks into flakes that clog the recycling equipment. Only a very few recyclers have equipment and processes that can handle packaging with these coatings; the vast majority of them reject this packaging.

Another alternative is coating made from polylactic acid (PLA), a polymer derived from plants, usually corn. The primary appeal of PLA is that, unlike standard polymers based on petroleum, PLA is bio-based and compostable.

But PLA as packaging-liner material is problematic for several reasons. It’s significantly more expensive than PE, and to get the full benefit of its environmental friendliness—i.e., its compostability—it has to be processed at a large-scale municipal composting center. These are rare in the U.S., and even where they exist, they would have to receive PLA-coated packaging as segregated loads.  Compostable coatings provide the same challenges to paper recycling processes as PE.  For the consumer bringing their food home, the task of composting packaging is virtually impossible because it would require customers to seek out the few municipal collection points dedicated to composting of packaging—which practically none would be willing to do.

However, there is a new coating available that satisfies all three parts of the trifecta.

EarthCoating, developed by Smart Planet Technologies, is a packaging coating that has high barrier performance, does not contain PFCs, and is priced comparably to PE.  However, EarthCoating is a recyclable material because it’s engineered for compatibility with paper recycling systems and doesn’t pose PE’s problem of clogging recycling equipment. During the pulping that is the first part of recycling, this coating breaks into flakes that are small enough not to clog filters, and denser to be removed along with dirt and grit.

The coating is available to converters who want to use it for all types of foodservice packaging that needs barriers: folding cartons, trays, wrappers, clamshell containers, and more. “There are millions of boxes with EarthCoating on retail shelves now”, Gasparik says. “Applications include frozen seafood cartons, fruit and vegetable trays, takeout boxes, paper cups, and other foodservice packaging applications.”

“We’re thrilled to have found out about this coating,” says Tamara Sloan, owner of The Mill Coffee & Tea coffeehouse located in Lincoln, Nebraska. “The fact that it can be used as a low-cost, environmentally-friendly paper barrier material falls right in line with our sustainable packaging initiatives. Whether it be for our paper cups, sandwich wraps or take-out boxes, it makes sense to do the right thing and use EarthCoating for our packaging.”

“This new coating gives converters and end users everything they want in a paperboard coating,” Gasparik says. “A safe coating that performs as well as any competing material, that’s cost-competitive, and makes the packaging material as recyclable as office paper or any other kind of bleached paper.”

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