Headlines about microplastics increasingly include advice on which packaging materials consumers should choose and how to use and store them, even as the underlying science continues to evolve. But as research in this area evolves, it is important to distinguish between what science has established and what researchers are still working to understand.
This important distinction was at the center of a recent letter to the editor from NAPCOR’s Executive Director Laura Stewart, published in The Washington Post in response to an article recommending several steps consumers could take to reduce potential microplastics exposure, including replacing plastic water bottles with stainless steel. Stewart’s central point: consumer recommendations should reflect what the evidence actually shows.
So, when it comes to PET bottles and microplastics, what does the science available actually tell us?
What We Know: PET Remains Approved for Food Contact
PET, or polyethylene terephthalate, is the plastic identified by the #1 resin identification code. It has been used safely for food and beverage packaging for decades and is among the most extensively studied and regulated packaging materials.
PET is approved for food contact by the US Food and Drug Administration (FDA), the European Food Safety Authority (EFSA), Health Canada, and other food safety authorities around the world.
That safety record is based on decades of scientific study, regulatory evaluation, and real-world use. Importantly, current microplastics research has not changed those food safety authorities’ conclusions about PET.
What the evidence says: Current scientific evidence continues to support PET as a safe food-contact packaging material.
What We Know: Detecting Microplastics Does Not Establish Harm
Micro- and nanoplastics have been detected in food, beverages, and the environment. But finding particles, by itself, does not demonstrate that they are causing harm. Current scientific evidence has not established that the levels of microplastics detected in food and beverages pose a risk to human health.
As Stewart wrote in The Washington Post, “Detecting a substance is not the same as demonstrating harm.”
The FDA has reached a similar conclusion, stating that current scientific evidence does not demonstrate that levels of microplastics or nanoplastics detected in foods pose a risk to human health. Simply put, detecting particles is one finding; demonstrating that those particles cause harm is another.
What the evidence says: The presence of microplastics alone does not demonstrate a human health risk.
What We Know: Consumer Recommendations Should Be Supported by Evidence
Consumers understandably want practical guidance about the packaging they use. But recommendations to switch from PET plastic bottles to another material should be supported by evidence that doing so actually reduces exposure or provides a health benefit.
Current research does not establish that. In fact, microplastics have been detected in beverages packaged in a range of materials.
Detecting microplastics across different packaging types does not establish that consumers should avoid these materials. Instead, it underscores how difficult it can be to identify the source of detected particles, and why material-specific recommendations require strong supporting evidence. Microplastics can come from multiple sources, and detecting them in a package does not establish that the material itself poses a health risk.
What the evidence says: Current research does not demonstrate that replacing PET bottles with alternative packaging materials reduces microplastic exposure or provides a health benefit.
What We Know: Switching Packaging Materials Can Create Environmental Trade-Offs
Packaging choices can also involve environmental trade-offs. Recommending that consumers replace one material with another based on a single emerging area of research can overlook differences in energy use, greenhouse gas emissions, recyclability, and other lifecycle impacts. Material recommendations should consider the broader environmental picture.
For example, lifecycle assessments have found that PET beverage bottles can have a significantly lower greenhouse gas footprint than some alternative packaging formats. For example, a typical PET soda bottle has less than half the total greenhouse gas footprint of an aluminum can and about a fifth of a glass bottle. Switching materials to address one potential concern can therefore increase impacts in another area.
That doesn’t mean one packaging material is always the best choice. It means environmental decisions should consider the full lifecycle of a package, from production and transportation through recycling or disposal, rather than focusing on a single attribute.
What the evidence says: Replacing one packaging material with another can shift environmental impacts rather than eliminate them.
What We Don’t Know: How Emerging Research Will Shape Our Understanding
Microplastics research is still developing, and there are important questions that deserve further scientific investigation.
NAPCOR supports continued, rigorous research that advances our understanding of microplastics, including their presence in the environment and their potential effects on human health. What matters is that conclusions keep pace with the evidence.
Emerging findings can deepen our understanding of microplastics without necessarily changing what decades of research have already established about the safety of a particular material. When research has not established a health risk, it should not be communicated as though it has.
What the evidence says: More research can help strengthen our understanding of microplastics, but uncertainty should not be treated as evidence of harm.
Following the Evidence
Consumers deserve clear, practical information about the materials they encounter every day, and they should be able to trust that health recommendations are grounded in the best available science.
Learn more about PET plastic, including its safety, recyclability, and environmental impact, on our PET Basics page.
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