A new scientific review has found that routine interactions with food packaging—such as opening bottles, unwrapping plastic-sealed items, or reusing containers—can release substantial quantities of micro- and nanoplastics into food and beverages, potentially contributing to widespread human exposure.
Published in the journal NPJ Science of Food and led by researchers from the Zurich-based Food Packaging Forum, the study systematically evaluated peer-reviewed data on the presence of plastic particles in food. It identified food packaging itself as a direct and measurable source of microplastic contamination.
“The research shows the number of microplastics increases with each bottle opening, so therefore we can say it’s the usage of the food contact article which leads to micro- and nanoplastic release,” said lead author Lisa Zimmermann, Scientific Communication Officer at the Food Packaging Forum.
The study builds on prior findings showing microplastics in foodstuffs such as beer, canned fish, rice, mineral water, tea bags, table salts, and soft drinks. But this is the first time researchers have mapped a clear correlation between the act of using packaging as intended—like twisting off bottle caps or heating contents in plastic— and the shedding of microplastics into food or drink.
Abrasion, Heat, and Reuse Intensify Shedding
The release of microplastics appears to be aggravated by typical consumer behavior, including repeated use, heat exposure, and even mechanical stress during opening. “There’s a higher number of manufacturing steps with ultraprocessed foods, which can increase the contact time with plastic food processing equipment,” noted Jane Muncke, the Forum’s Managing Director and Chief Scientific Officer. “Thus increasing the chance of micro- and nanoplastic migration.”
The team reviewed over a thousand studies and narrowed the pool to 103 for detailed analysis, ultimately identifying seven as highly reliable based on rigorous criteria. These studies showed significantly higher levels of contamination in ultraprocessed foods compared to minimally processed alternatives, largely due to greater contact with plastic during production and packaging.
In one cited example, one liter of bottled water contained an average of 240,000 plastic particles—90% of which were nanoplastics. Another test involving melamine bowls showed that repeated washing increased microplastic shedding, which then transferred into food upon use.
A Mounting Health Concern
While microplastic contamination in food is not a new discovery, the scale and implications of the findings have heightened concern among public health experts.
“This new study highlights food packaging and processing equipment as potentially significant sources of microplastic contamination in the food we eat, and ultimately in our bodies,” said David Andrews, Acting Chief Science Officer at the Environmental Working Group. “This study should raise alarm bells.”
Microplastics (defined as plastic fragments smaller than 5 mm) and nanoplastics (under 1 micrometer) are increasingly detected in human tissue. Studies have found them in the bloodstream, lungs, liver, placenta, and even in human brain and reproductive tissues. According to a March 2024 study, individuals with plastic particles in their carotid arteries were twice as likely to suffer a stroke, heart attack, or premature death within three years than those without.
Regulatory and Industry Implications
A previous investigation by the Food Packaging Forum in 2024 found more than 3,600 chemicals leaching into food from contact materials during manufacturing and storage, with 79 of those substances identified as carcinogenic or disruptive to the endocrine and reproductive systems.
Despite mounting evidence, standardized testing methods remain lacking across the field, which continues to hinder direct comparisons and regulatory response.
Megan Deeney, a plastics and global health researcher at the London School of Hygiene & Tropical Medicine, praised the methodological rigor of the study. “What is particularly important is that the authors take the time to extract and evaluate evidence on whether the presence of microplastics changed over time… this can help to identify the food contact material itself as a direct source,” she said.
Toward Systemic Change
Experts stress that reducing exposure requires more than individual effort. “This is not something that any individual can solve on their own,” Deeney noted, adding that systemic action is required to limit plastics production and pollution.
As the global community prepares for the final round of negotiations on the UN’s Global Plastics Treaty in Geneva this August, the study may add urgency to the call for legally binding international regulations.
“There’s a critical opportunity for individuals to engage with governments to demand strong, ambitious action on plastics,” said Deeney.
In the meantime, health experts recommend avoiding heating food in plastic containers, steering clear of plastics with recycling code 3, and switching to stainless steel or glass alternatives wherever possible. But as the latest data suggests, even these precautions may be insufficient without broader industry and legislative intervention.
