Titanium dioxide is a white powder used to color foods, but the European Union banned it because of safety concerns. Scientists wanted to understand if the titanium dioxide used in American foods is similar to samples tested for cancer risk. Using several different tools to examine the particles, researchers found that while there were some small differences, the titanium dioxide used in US food coloring had similar properties to the tested samples. This research helps food safety officials decide whether this additive is safe to use in foods.

The Quick Take

  • What they studied: Scientists compared the tiny particles in titanium dioxide food coloring used in America with titanium dioxide that was tested for safety in a 2-year study.
  • Who participated: This wasn’t a study with people. Instead, researchers examined samples of titanium dioxide powder using different laboratory tools to measure and compare their properties.
  • Key finding: The titanium dioxide used in US food coloring had very similar properties to the samples that were tested for safety, even though some small differences were noticed when measured different ways.
  • What it means for you: This research suggests that safety testing done on titanium dioxide samples is likely relevant to the titanium dioxide actually used in American foods. However, this is one study, and food safety decisions involve many other factors and ongoing monitoring.

The Research Details

Scientists obtained samples of titanium dioxide food coloring used in the United States and compared them to titanium dioxide samples similar to those used in a previous 2-year safety study. They used four different laboratory techniques to examine the samples: dynamic light scattering (which measures particle size in liquid), transmission electron microscopy (which takes very detailed pictures of tiny particles), scanning electron microscopy (which shows surface details), and Raman spectroscopy (which identifies what material the particles are made of). They also tested the samples in two different ways—by shaking them and by using sound waves to break them apart—to see if preparation method mattered.

When safety testing is done on a food additive, regulators need to know that the additive being tested is the same as what’s actually used in foods. If the properties are different, the safety results might not apply to real-world use. This study bridges that gap by directly comparing the two.

This is a technical laboratory study that carefully measured multiple properties of the samples using established scientific methods. The researchers were thorough in using different measurement techniques and preparation methods. However, the study doesn’t involve testing in animals or people, so it only tells us about the physical and chemical properties of the particles, not whether they’re actually safe to eat.

What the Results Show

When researchers measured particle size using one method (dynamic light scattering), they found some differences between shaken samples of the two types of titanium dioxide. However, when they used sound waves to break apart the particles before measuring, the differences disappeared. This suggests the differences might have been due to how the particles clumped together rather than real differences in the particles themselves. When scientists looked at detailed pictures taken with electron microscopes, they found that particles ranged from about 14 nanometers to 704 nanometers in size across all samples—a very wide range, but similar across all the titanium dioxide types tested. All the samples were made of the same form of titanium dioxide called anatase. The surfaces of all particles looked similar under the microscope.

Scientists found that the titanium dioxide used in US food coloring and one of the tested samples had similar electrical properties when dissolved in water at different pH levels. However, the samples used in the previous safety study contained some trace elements (impurities) that weren’t found in the US food coloring samples. Despite these minor differences, the overall properties were comparable enough that the safety testing appears relevant to the food coloring actually used.

This research directly addresses a gap in knowledge about whether the titanium dioxide tested for safety in previous studies matches what’s actually in American foods. The European Union’s ban on titanium dioxide in food was based on concerns that couldn’t be completely ruled out, making this comparison study important for understanding whether existing safety data applies to current food products.

This study only examined the physical and chemical properties of the particles—it didn’t test whether they’re safe to eat. The study doesn’t tell us about long-term health effects or how the body processes these particles. Additionally, the sample sizes and specific sources of the titanium dioxide samples weren’t detailed in the available information. The findings apply specifically to the samples tested and may not represent all titanium dioxide products used in foods.

The Bottom Line

This research suggests that safety testing done on titanium dioxide is likely relevant to the titanium dioxide used in American food coloring, based on their similar physical properties. However, food safety decisions should consider this research along with other studies and ongoing monitoring. Confidence level: Moderate—this is one technical study that supports but doesn’t definitively prove safety.

Food safety regulators and scientists should pay attention to this research. People concerned about titanium dioxide in their food should know that the US still allows it, while the EU banned it. If you have specific health concerns, talk to your doctor. This research is most relevant to policymakers deciding on food additive regulations.

This is a laboratory study, not a health intervention, so there’s no timeline for personal health benefits. The findings may influence food safety policy decisions over months to years as regulators review the research.

Want to Apply This Research?

  • Track foods you consume that contain titanium dioxide (listed as ‘TiO2’ or ‘E171’ on ingredient labels) and note any digestive symptoms or concerns. Record the frequency of consumption weekly.
  • If concerned about titanium dioxide exposure, users can use the app to identify and reduce consumption of heavily processed foods that contain this additive, focusing on whole foods instead.
  • Maintain a long-term log of processed food intake and any health observations. Share this data with your healthcare provider if you have specific health concerns related to food additives.

This research examines the physical properties of titanium dioxide particles and does not directly test health effects in humans or animals. While this study helps regulators understand whether previous safety testing applies to current food products, it does not prove that titanium dioxide is safe or unsafe to eat. Food safety decisions are made by regulatory agencies like the FDA based on multiple studies and evidence. If you have specific health concerns about food additives, consult with your healthcare provider. This information is for educational purposes and should not replace professional medical advice.