Pile of empty plastic packaging containers.

After examining over 700 publications, researchers concluded that reused and recycled plastics are likely to transfer toxic chemicals to the foods they contain. | Konektus Photo/Shutterstock

A recent analysis by Switzerland-based Food Packaging Forum reviewed hundreds of scientific studies and concluded that recycled and reused food-contact plastics can accumulate and release chemicals of concern. 

Published by Cambridge University Press, the study noted that reusing and recycling plastics can lead to “unintended negative impacts, because hazardous chemicals, like endocrine disrupters and carcinogens, can be released during reuse and accumulate during recycling.” 

“In this way, plastic reuse and recycling become vectors for spreading chemicals of concern,” the report noted. “This is especially concerning when plastics are reused for food packaging, or when food packaging is made with recycled plastics. Therefore, it is of utmost importance that care is taken to avoid hazardous chemicals in plastic food contact materials.”

Greenpeace also recently released a review of studies that reached a similar conclusion. 

The Food Packaging Forum is a nonprofit foundation that shares information on chemicals in all food packaging materials and their impacts on human health.

The review used the Database on Migrating and Extractable Food Contact Chemicals, which is based on over 700 scientific publications on plastic food contact materials, such as packaging, utensils, plates and baby bottles.

Troubling findings

The researchers noted in the study that discussion of chemical accumulation is often overlooked when talking about plastics. It’s especially important with regard to recovered plastic from ocean cleanups because “persistent organic pollutants may be present.”

In addition, the study pointed out that some tableware labeled as natural or compostable is actually melamine resin mixed with bio-based powders or fibers, such as bamboo. Melamine affects the kidneys, the study noted, and bio-based fillers decrease the stability of the materials that contain them, making migration of melamine and formaldehyde in the products more likely. 

There is experimental evidence, the study stated, that RPET contains chemical contaminants, such as the endocrine-disrupting chemical BPA and the carcinogens benzene and styrene, that are introduced during use, processing and recycling, and those can migrate into the food or beverages contained by the packaging. 

“The question of how to assess the safety of the high number of chemicals found not only in recycled plastic polymers, but also in virgin plastics, needs to be urgently addressed,” the report noted.

The authors called for more study into chemical migration, especially as the U.S. FDA and the European Food Safety Authority have been issuing more and more favorable opinions on the suitability of recycling processes for producing food-contact packaging. 

“A shift towards materials that can be safely reused due to their favorable, inert material properties could be a promising option to reduce the impacts of single-use food packaging on the environment and of migrating chemicals on human health,” the study noted. 

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Bruno Folcieri