Titanium Dioxide (E171) – EU Court Challenges Titanium Dioxide Declassification as Carcinogen

Since our previous article regarding titanium dioxide and the EU’s ban on its use as a food additive in August 2022, the regulatory landscape for titanium dioxide (TiO₂, or E-number E171) has continued to evolve, particularly within the EU where there has been renewed judicial scrutiny and disagreement among the EU’s institutions on whether it should be classed as a carcinogen and regulated accordingly. 

Potted history of titanium dioxide as a food additive

Titanium dioxide is a naturally occurring oxide of titanium. It is a white opaque powder which has a wide range of applications, from use as a white pigment in paints and inks as well as being used as a food additive, and as a UV filter for cosmetics and sunscreen.

Prior to its classification as a carcinogen and subsequent ban as a food additive in 2022 across the EU, titanium dioxide was permitted as a food additive, primarily for its ability to whiten or brighten the appearance of food.

On a local level in the EU, France had already banned the additive in 2019, and the Netherlands Food and Consumer Product Safety Authority had also expressed concerns on its possible health effects. The European Food Safety Authority (“EFSA”) conducted a review in 2016, which concluded that the substance should not be considered safe as a food additive due to uncertainties around possible inflammation and neurotoxicity. Following this review and the adoption of Commission Regulation (EU) 2022/63, amending Annexes II and III to Regulation (EC) No 1333, EFSA implemented a ban on its use in food, halting the legal sale of food containing titanium dioxide in the EU from 7 August 2022.

• Ultimately the use of the substance as an ingredient in foods has been banned since August 2022.

Potted history of titanium dioxide for cosmetic and industrial uses

In 2020, the European Commission, acting on the recommendation of the European Chemicals Agency’s (“ECHA”) Risk Assessment Committee (“RAC”), classified certain powder forms of titanium dioxide as a Category 2 carcinogen by inhalation under Regulation (EC) No 1272/2008 on the classification, packaging and labelling of chemical substances and mixtures (the “CLP Regulation”). This classification was based on studies indicating potential carcinogenic effects when inhaled, particularly in occupational settings. With this came mandatory requirements for products containing the substance to carry specific hazard warning labels and safety measures.

However, the EU General Court subsequently annulled the Commission’s decision in November 2022, because it considered that the scientific information on which the Commission relied was in fact unreliable. The ECHA’s RAC had apparently not adequately examined the accumulation of nano-sized titanium dioxide particles and its impact on particle density when assessing toxicity. The General Court concluded that the carcinogenicity observed by the RAC was not an inherent property of titanium dioxide itself, but rather a result of the physical accumulation of particles in the lungs which caused an inflammatory response.

• Ultimately, the substance was classed as a carcinogen in 2020 and permitted only with specified safety warnings. However, this was annulled in November 2022 due to scientific evidence, rendering the classification as a carcinogen to be void.

Recent scrutiny

The legal status of titanium dioxide’s classification came under recent scrutiny from a regulatory legislative point of view on 6 February 2025. With the support of the French Government and the European Commission, the EU Advocate General issued a non-binding recommendation to the European Court of Justice (“ECJ”) that the General Court’s annulment be overturned and the original classification as a suspected carcinogen be reinstated.

The basis for its recommendation is that the General Court exceeded its judicial mandate by substituting its own scientific assessment for that of the RAC, rather than limiting its review to procedural aspects. In its challenge, the Advocate General argued that:

• Under the CLP Regulation, the concept of “intrinsic properties” should be interpreted broadly, encompassing not only chemical composition but also physical characteristics and their impact on health.
• The General Court had dismissed the RAC’s conclusions, favouring the stance that “decisive” evidence was needed. This was inconsistent with the comprehensive assessment principle of the CLP Regulation. Under the CLP framework, when scientific evidence is uncertain, the European Commission (guided by the RAC) have the final say in interpreting such data.

Whilst the Advocate General’s opinion is not binding, it puts forward a legal basis for the ECJ to potentially reinstate the carcinogenic classification. It is expected that the ECJ will issue its decision later this year.

Implications of the recent scrutiny for the food and chemicals industry

If the ECJ follow the recommendation and reinstate the classification manufacturers and importers of titanium dioxide in the EU would face renewed obligations, including updated labelling, safety data sheets, and potentially reformulation of products to comply with stricter regulatory standards. There is also a risk of reduced consumer confidence and market demand for products containing titanium dioxide.

In addition to this, reinstatement of the classification without addressing scientific ambiguities set out by the General Court, could set a precedent for future substance classifications based on precaution rather than robust scientific consensus. The EU often applies the precautionary principle in its approach to chemical safety. Under this principle, if there is uncertainty about the safety of a substance and it cannot be conclusively demonstrated to be safe, the EU may restrict or even ban its use as a protective measure for public health and the environment. This approach can result in substances being outlawed even in the absence of definitive evidence of harm, prioritising caution where scientific data is inconclusive.

By contrast, the UK has not followed the EU in outlawing titanium dioxide in any products, nor have the UK regulatory authorities classified titanium dioxide in the same way as the EU, and it remains permitted for use in products within the UK. This divergence highlights the current differences in regulatory approach: while the EU may act to restrict substances on the basis of precaution, the UK requires a higher threshold of scientific evidence before imposing similar restrictions.

Co-authored by Rebecca Shipton, Trainee Solicitor at CMS.