Are They Putting Nanoparticles in Food? An In-Depth Look at Additives and Packaging

October 25, 2025 •

3 min read

According to the European Food Safety Authority (EFSA), food-grade titanium dioxide (E171) contains a significant proportion of particles in the nano range, and is no longer considered safe as a food additive. This has heightened public interest regarding the use of engineered nanoparticles in food, affecting both direct additives and indirect contact materials like packaging.

Quick Summary

Processed and packaged foods can contain nanoparticles from natural sources, traditional processing, intentional additives, or packaging migration. Specific engineered nanomaterials like titanium dioxide and silicon dioxide are used as additives, though their regulatory status and safety assessments vary globally. Nanomaterials are also critical for innovative packaging that extends shelf life and improves food safety, raising concerns about potential migration and health risks. Researchers use complex analytical techniques to detect and characterize these nanoscale materials.

Key Points

Natural vs. Engineered: Many foods naturally contain nanoscale materials, like casein in milk, which are different from intentionally manufactured nanoparticles.
Titanium Dioxide (E171): This whitening additive is banned in the EU due to genotoxicity concerns but is still permitted in the U.S., highlighting a major regulatory split.
Silicon Dioxide (E551): Used as an anti-caking agent, it is generally considered safe and exists primarily as larger aggregates, not individual nanoparticles.
Packaging Concerns: Nanomaterials in packaging provide antimicrobial and barrier properties, but raise health concerns due to the potential for migration into food, particularly at high temperatures.
Safety Depends on the Nanoparticle: The health risks of nanoparticles depend on factors like size, shape, dose, and composition; risk cannot be automatically assumed from the macro-sized material.
Detection Challenges: Pinpointing and measuring nanoparticles in food is scientifically challenging, requiring specialized and advanced analytical techniques.

The Surprising Presence of Nanomaterials in Food

Most people are unaware that they consume nanomaterials regularly. These materials can be broadly categorized by their origin: naturally occurring, traditionally produced, or intentionally engineered.

Natural and Traditionally Processed Nanoscale Structures

Natural: Many foods naturally contain nanoscale structures, such as casein micelles in milk and cell organelles in fresh produce.
Traditional Processing: Standard food manufacturing techniques like homogenization and milling can create nanosized particles from fat droplets or starches.

Engineered Nanomaterials (ENMs)

Engineered nanoparticles are intentionally created to improve food properties like texture, flavor delivery, or shelf life. These include inorganic materials like titanium dioxide and silicon dioxide, as well as organic nanoparticles made from lipids or proteins.

Common Nanoparticle Additives: The Case of E171 and E551

Two notable examples of nanoparticle use as food additives are titanium dioxide and silicon dioxide.

Titanium Dioxide (E171)

Used as a white pigment in products like sweets and sauces. The EU banned E171 in 2022 following an EFSA assessment citing concerns about genotoxicity, although the U.S. FDA still permits its use. Studies suggest low absorption but potential accumulation in the body.

Silicon Dioxide (E551)

Often used as an anti-caking agent in powdered foods. It is generally considered safe within approved levels by the FDA and EFSA and is primarily used in aggregated, not isolated nanoparticle, form.

Beyond Additives: Nanotechnology in Food Packaging

Nanomaterials enhance food packaging to improve material properties and safety.

Active and Smart Packaging

Active Packaging: Nanoparticles like silver can provide antimicrobial properties or scavenge oxygen to extend shelf life.
Smart Packaging: Nanosensors can monitor food freshness and signal spoilage.

Potential for Migration

There are concerns that nanoparticles from packaging may migrate into food under conditions like high heat or acidity, requiring careful regulatory evaluation.

Health and Safety Concerns

Research is ongoing into the potential risks of engineered nanoparticles. Their small size can lead to oxidative stress, bioaccumulation in organs like the liver and spleen, and potential genotoxicity.

The Challenge of Detection

Identifying and measuring nanoparticles in food is complex, requiring advanced techniques.

Microscopy & Spectroscopy: Techniques like TEM, SEM, and DLS help visualize and size nanoparticles.
Advanced Analysis: Methods like FFF and ICP-MS are used for separation and detection.

Comparison of Nanoparticles in Food


Aspect	Engineered TiO2 (E171)	Engineered SiO2 (E551)	Nanoclays (Packaging)	Naturally Occurring (e.g., Casein Micelles)
Primary Use	Whitening agent in candies, sauces	Anti-caking agent in powders, spices	Gas barrier, strengthening agent	Nutrient delivery
Regulatory Status (EU)	Banned as food additive since 2022 due to genotoxicity concerns	Generally recognized as safe (re-evaluated in 2024)	Use in food contact materials regulated	Exempt from regulation
Regulatory Status (US)	Approved as a food colorant (max 1% by weight)	Generally recognized as safe (GRAS)	Use in food contact materials regulated	Exempt from regulation
Primary Form	Contains significant proportion of nano-sized particles	Primarily larger aggregates, not isolated nanoparticles	Nanoscale layers within polymer matrix	Nanosized protein clusters
Key Concern	Genotoxicity and accumulation in organs	Potential for adverse effects at high doses (debated)	Migration into food and subsequent toxicity	Generally no health concerns recognized

Conclusion

Nanoparticles are present in food from natural sources, traditional processing, or intentional engineering for additives and packaging. Their safety depends on the type, with some engineered nanoparticles like titanium dioxide facing bans due to potential risks, while others like silicon dioxide are deemed safe when used as aggregates. Consumers should be aware that regulations and scientific understanding are evolving. Reading labels and staying informed are key. Further research is essential to fully understand the long-term health and environmental impacts of engineered nanoparticles.

For more detailed information on regulations and safety assessments in the EU, you can visit the European Food Safety Authority's website [https://www.efsa.europa.eu/en/news/titanium-dioxide-e171-no-longer-considered-safe-when-used-food-additive].

Frequently Asked Questions

Nanoparticles in food are materials measuring between 1 and 100 nanometers in at least one dimension. They can be naturally present (e.g., milk protein), a byproduct of processing (e.g., homogenization), or intentionally engineered additives.

Yes, engineered nanoparticles are found in certain processed foods. For example, some food additives like silicon dioxide (E551) and previously titanium dioxide (E171) use materials that contain nano-sized particles.

Safety is a point of global regulatory divergence. The European Food Safety Authority (EFSA) declared it unsafe as a food additive in 2021 due to genotoxicity concerns, leading to an EU ban. However, the U.S. FDA continues to permit its use.

Silicon dioxide (E551) is a food additive primarily used as an anti-caking agent to prevent clumping in powdered products like spices, milk powder, and salts. It is generally regarded as safe by regulatory bodies.

Research indicates that nanoparticles from packaging, such as nanosilver or nanoclay, can migrate into food, especially under certain conditions like high heat or acidity. The extent and potential harm of this migration are still being studied.

Regulations vary globally. In the EU, rules for 'novel foods' require specific labeling, and the E171 ban effectively requires manufacturers to reformulate products. Some jurisdictions or consumer groups advocate for more explicit labeling of engineered nanomaterials.

Potential health risks include oxidative stress, DNA damage (genotoxicity), inflammation, and accumulation in organs like the liver and spleen. The toxicity depends on factors such as nanoparticle type, size, dose, and the specific food matrix.