Micro- and nanoplastics are being spoken about more and more in the media, by policymakers, and by consumers. But what are they? Is there a reason for concern? And what does AURORA’s research hope to achieve?
Take a look at some of the most frequently asked questions (and our answers) in the sections below grouped by theme.
Still have questions or want to learn more about our research? Check out our pages about the project, results, related resources, the latest news, and our research team. Or feel free to contact us.
FAQ last updated: April 2, 2025
Micro- and nanoplastics (MNP)
Micro- and nanoplastics (MNPs) are plastic particles below 1 mm and 1 µm in diameter. They have different shapes, sizes, and surface characteristics. They can be made of different polymers and contain different additives and chemicals.
Microplastics are plastic particles between 1 μm and <1000 μm, while nanoplastics are <1 µm. However, different stakeholders sometimes use different size definitions.
MNPs are generated by the degradation and fragmentation of plastic products due to biological, chemical, and physical processes, and by abrasion from larger plastic pieces. In some cases, MNPs are intentionally manufactured such as microbeads in cosmetics (exfoliants in facial scrubs and toothpaste) and additives for abrasive cleaning or polishing products.
No. Plastics degrade into smaller particles not visible to the naked eye, but they are still present.
Yes. MNPs are present in various foods and beverages. They can originate, for example, from plastic food packaging and processing equipment. Their omnipresence in the environment, different concentrations in foods and cosmetics, and different consumer behaviors make it difficult to estimate total ingestion.
Experimental evidence suggests that MNPs below 10 µm can cross cell membranes and potentially accumulate in organs, but more research is needed.
Exposure to MNPs is a potential human health hazard, but data on health risks is still limited. Laboratory studies show potential impacts like cellular damage and inflammation.
Pregnant women and fetuses may be more vulnerable to MNP exposure, but the extent and consequences of such exposure are still largely unknown.
Human health impacts of MNPs are assessed through in vitro, in vivo, and epidemiological studies, combined with state-of-the-art analytical tools.
Exposure to MNPs can be reduced by limiting the use of (single-use) plastic packaging, synthetic clothing, products containing microbeads (e.g., certain cosmetics), or plastic kitchenware. However, complete avoidance of MNPs is not possible due to their widespread presence in air, food, and water.
Biodegradable plastics often require specific conditions (e.g., high temperature, moisture) to break down completely. These conditions are rarely met in home composts and sometimes not even in industrial composting facilities. Consequently, they can still contribute to MNP pollution.
Yes, most likely, since during storage and use (e.g., opening of a plastic bottle, tea brewing) plastic particles are released into the food or beverage. But quantifying exposures is difficult, it can change based on what type of product/plastic you are using. Glass or stainless steel containers, when possible, are a better choice as they are more inert materials and do not contain plastic. If you have to use plastics, avoid their exposure to sunlight, high temperatures, and too much shaking since this favors the abrasion of small plastic particles.
Yes, rubber particles are also considered microplastics. Most rubber particles are from car tires. As of right now, AURORA does not study rubber particles.
Possibly, but right now we lack the data to quantify what they would be. Therefore, as a precaution, it might be advisable to minimize the exposure to MNPs as much as possible.
In principle, there are two approaches:
- Particle counting: Using an image of the MNPs under a microscope (using approaches such as FTIR and AFM), scientists can count the number of particles and see what size and shape they have.
- Mass-based assessments: Scientists can measure the weight of MNPs to quantify the exposure (using a method known as pyrolysis GC-MS).
Yes, limited studies from 2024 and 2025 show that MNPs can be present in the human brain and that they potentially accumulate there. The potential impact of MNPs on the brain is still unclear, but first studies found MNP levels to be higher in the brains of people with dementia.
Potentially, yes. The sources of exposure can be different and may depend on ecosystems and geographical regions. MNPs are very lightweight and easily transported by air and water, which has resulted in their detection in very remote regions (e.g., the Arctic) and even the deep sea. Therefore, it is likely that most global environments are affected to a certain extent by MNP pollution.
Humans use a lot of plastic products in their everyday lives including for food packaging and cosmetics. The normal and intended use of plastic food packaging has been shown to lead to the migration of MNPs into the foods we eat, and MNPs are intentionally used in some cosmetic products we put on our skin.
Complete assessments of MNPs in all types of foods are missing to date, and the use of different measurement techniques and ways of data reporting do not allow for a reliable comparison between studies. Generally, MNPs have been detected in many types of foods, including salt, fish and other seafood, honey, tea, milk, and beer. More research is needed to see whether these levels have a significant impact on human health.
Humans use a lot of plastic products in their everyday lives including for food packaging and cosmetics. The normal and intended use of plastic food packaging has been shown to lead to the migration of MNPs into the foods we eat, and MNPs are intentionally used in some cosmetic products we put on our skin.
Yes, this is part of AURORA’s ongoing efforts.
Indeed, risk assessment of MNPs is challenging because their risks can come from the fact that they are very small particles (with different sizes and shapes) as well as from the many (hazardous) chemicals they can contain.
While assessing their potential risks as small particles is still ongoing, it is already possible to assess the risks posed by the chemicals plastics can contain (considering their chemical composition, hazard properties, migrating mixtures, and quantifying exposures).
AURORA has developed a roadmap towards assessing the risks of MNPs on early-life health.
As of now, not much. While there are some reported hotspots where MNP concentrations were found to be particularly high in the environment, human health outcomes related to MNP exposures have so far not been described.
While assessing their potential risks as small particles is still ongoing, it is already possible to assess the risks posed by the chemicals plastics can contain (considering their chemical composition, hazard properties, migrating mixtures, and quantifying exposures).
AURORA has developed a roadmap towards assessing the risks of MNPs on early-life health.
Yes, data show that inhalation of any kind of particles can be associated with health risks. A general rule is the smaller the particle the deeper it gets into the lungs and the higher its potential health risk. Notably, in occupational settings, e.g., in a manufacturing or construction company, exposure levels tend to be higher.
chemicals in plastics
There is little to no obligation for manufacturers to indicate ingredients used to produce plastics. Furthermore, plastics can contain many additional chemicals that are non-intentionally added substances (NIAS). These can be contaminants, breakdown products, or reaction by-products introduced during processing or use of a plastic product. This makes it very difficult to determine the chemical composition of a plastic product without experimental analysis.
Plastics can contain harmful chemicals that migrate into our food or into the environment, which can result in health risks for humans and wildlife. Chemical migration is influenced by factors such as temperature, storage time, and food chemistry.
Some chemicals that can be in plastics are known to be harmful to our health, such as endocrine disruptors that can mimic or disrupt the body’s hormones or carcinogens that can cause cancer. However, every plastic can contain different chemicals, our exposure levels to these chemicals vary, and we are often exposed to mixtures of chemicals that can affect their toxicity. This all makes assessing the health risks of plastics complex and difficult to generalize.
No. Bioplastics often contain similar or even higher quantities of chemicals and are not inherently safer than conventional, fossil fuel-based plastics.
Yes. MNPs are plastics, and they can have a higher surface-to-volume ratio, leading to faster chemical release. They can also absorb environmental contaminants around them.
The aurora project
Actionable eUropean ROadmap for early-life health Risk Assessment of micro- and nanoplastics (AURORA).
AURORA started in April 2021 and will run for 5 years until March 2026.
AURORA is a consortium of researchers from 11 institutes across 9 countries, coordinated by UMC Utrecht and funded by the European Commission.
AURORA is needed to understand the impact of MNPs on pregnancy and early-life health, particularly their ability to cross the placental barrier.
AURORA combines advanced methods for toxicological, exposure, and epidemiological studies with scalable technologies for large-scale evaluation of maternal and fetal MNP exposures.
AURORA will enhance exposure assessment capabilities for measuring MNPs in tissues and develop techniques for biomonitoring and assessing early-life health impacts.
Email info@AuroraResearch.eu or contact a responsible team member directly.
CUSP is a consortium of five research initiatives studying the health impacts of MNPs. AURORA’s role is to assess MNP impacts on developing fetuses. More information about the CUSP cluster is available on its website.
