Characteristics and Toxicity of an Everyday Polyamide : A study of potential health risks of micro- & nanoplastics released from nylon

Abstract

Plastic has been a revolutionary material in human history. Plastic materials have several desirable
properties, such as durability, low production costs, and versatility. This helps explain the increase
in their use and production over the past 100 years. Plastics are synthetic polymers, with long
repeating chains of monomers; this creates structures that are chemically stable and durable. The
overconsumption of plastics has, however, made these desirable properties a burden. Plastics are
hard to break down and recycle and do so very slowly in natural pathways. This means that the
issue of plastic pollution grows, leading to environmental damage. Recent studies have also shown
that there are micro- and nanoplastics that are released from plastic pollution, which end up in the
brain and other organs, because these plastic particles can cross natural barriers due to their small
size and unique properties. In this study we focus on oven bags, a nylon-based cooking utensil.
The oven bag is exposed to mechanical weathering and heat while being in direct contact with
food. This could lead to the release of micro- and nanoplastics from the oven bag, which would
get directly released into the food and liquids inside the oven bag. The study looks at physical and
chemical characteristics of the released particles in relation to potential toxicity that could occur.
This is done with D. magna toxicity tests, NTA analysis, TEM-imaging and FTIR-spectroscopy.
The results show that toxicity occurs when the oven bag is baked. Other processing methods
generally extended the life of D. magna. There is significant proof that PA micro- and nanoparticles
can cause toxicity which is heat dependent. Furthermore, oven bags that are cooked at higher
temperatures cause more toxicity. Particles that were already released could not become toxic
retroactively due to high temperatures.

Popular Abstract

Oven bags are kitchen tools used for cooking meat and vegetables in an oven. The oven bag is commonly made from nylon, a widely used plastic in modern society. In this study, we investigated whether these bags release toxic materials, more specifically micro and nanoplastics which might be released during typical use.

Earlier research has shown that plastic particles cause worrying health concerns, in the form of inflammation, oxidative stress and more. This master’s thesis focuses on the potential toxic effects of nylon, particularly the minute particles released during heating and or handling. The goal was to decide whether nylon oven bags release hazardous micro- or nanoparticles during
their intended use and to characterize these particles in terms of concentration, size, chemical
structure, and shape.

The nylon oven bags were baked in an oven, mechanically broken down or boiled to see if plastic particles were released and to investigate potential toxicity from these released particles.The characterization and analysis were done with several scientific methods which include nanoparticle tracking analysis (NTA), transmission electron microscopy (TEM), Fourier transform infrared spectroscopy (FTIR) and AlgaeLabAnalysis (ALA). These techniques were done to deepen our understanding of the micro- and nanoplastics released from nylon. The
results show that particles are indeed released from the oven bag during baking, boiling and mechanical breakdown. Surprisingly, the released particles could both shorten and extend the average lifespan of our model organisms, Daphnia magna. Furthermore, the toxicity stemmed from the something called dissolved molecules, smaller components which get released from material. This was displayed by separating the released particles from the dissolved molecules.
Additionally, the toxicity showed strong links to the cooking temperature. Therefore, toxicity increased when the cooking temperature increased. The lifespan for the Daphnia magna got extended when the oven bag was mechanically broken-down with a hand blender. Additionally,the mechanical breakdown processes showed to reduce the toxicity of particles originally released during baking, which were proven to be toxic.

In conclusion, this study shows that dissolved molecules released from nylon during baking are toxic to Daphnia magna. The particles and dissolved molecules that were released by mechanical breakdown posed no immediate health risk. Plastic pollution could potentially pose a threat if they are exposed to high enough temperatures. These findings suggest that we should be even more mindful when choosing to use single-use products made from nylon. This study does not
solve any problems but brings attention to the unseen issue of plastic toxicity and lays some groundwork for a dialog and solutions to the rising issues.

• author: Boo, Kevin
• supervisor: Tommy Cedervall; Martin Lundqvist; Mikael Ekvall
• organization: Biophysical Chemistry
• course: KFKM05 20251
• year: 2025
• type: H3 - Professional qualifications (4 Years - )
• subject: Chemistry; Biology and Life Sciences; Technology and Engineering
• keywords: Nanoplastics, Microplastics, toxicity, daphnia magna, algae, nylon, polyamide, plastics, toxicity tests, oven bag, biophysical chemistry
• language: English
• id: 9198620
• date added to LUP: 2025-06-13 15:47:14
• date last changed: 2025-06-13 15:47:14