We’ve probably all drank from a PET bottle at some point in our lives. But what actually is PET? Can it really be recycled infinitely? Are there any chemical safety concerns related to PET? Let’s take a look at what the science says!
PET stands for polyethylene terephthalate and is a type of transparent, lightweight, rigid plastic. Its most common applications include drinking bottles and food containers, but also synthetic fibres used for clothing. It is estimated that approximately 500 billion PET bottles are produced each year globally.
A big advantage of PET over other plastics is that its recycling process is well established. Notably, recycled PET is allowed for food contact purposes in many regions, including the EU and US.
The US PET collection rate in 2023 was 33%, and the average post-consumer recycled PET content used in US bottles and jars was 16.2% (https://napcor.com/news/2023-pet-bottle-recycling-reach-new-heights/). In Europe, 75% of PET beverage bottles were collected for recycling in 2022, with an average post-consumer recycled PET content of 25% (https://petcore-europe.org/images/2025/in-europe-today-8-unep-article.pdf).
A report on the circularity of PET by @Zero Waste Europe showed that most PET recovered from bottles in Europe does not make its way back into new PET bottles. Often, PET bottles are downcycled into other products such as clothing or carpets instead of recycled into new bottles (https://zerowasteeurope.eu/press-release/new-report-pet-the-most-circular-of-all-plastics-is-far-from-real-circularity/). As a non-permanent material, PET cannot be recycled infinitely as the polymer chains break down and require the addition of virgin polymer.
Research has shown that hazardous chemicals can be present in and migrate from PET bottles into food, including so-called oligomers. Oligomers are small molecules made of just a few repeating polymer units. They can be present in PET food contact materials (especially recycled ones) and can migrate into food and beverages. A lot of knowledge gaps concerning their safety remain.
