ANSES’s work on titanium dioxide

Expert appraisals that contributed to it being banned as a food additive

The food additive E171, used for its colouring and opacifying properties, contains particles of titanium dioxide. Between 2017 and 2022, ANSES carried out several expert appraisals on the risks associated with its ingestion. Each of these concluded that it was not possible to resolve the uncertainties regarding the safety of the additive E171. Some research results suggest that TiO2 may promote the development of cancer or be genotoxic, but the available data are not sufficiently robust to be able to rule on the toxicity of the food additive. These uncertainties led to its use in foodstuffs being suspended in France in January 2020 and banned in the European Union in January 2022 following an assessment by the European Food Safety Authority (EFSA). 

Proposal to classify the substance as carcinogenic by inhalation

In 2015, ANSES submitted a request to the European Chemicals Agency (ECHA) to classify TiO2 as a presumed carcinogen by inhalation (Category 1B) under the CLP Regulation on the classification, labelling and packaging of dangerous substances and mixtures. According to ANSES, based on several studies, TiO2 is a proven carcinogen by inhalation for animals.

In 2017, ECHA's Committee for Risk Assessment concluded that TiO2 in all its forms should be classified as a suspected human carcinogen (Category 2) by inhalation[JA1] . In 2019, this decision was ratified by the European Commission, obliging manufacturers to inform workers of the risks involved in handling products containing TiO2, through the use of appropriate labelling.

However, this classification was challenged by manufacturers and annulled by the General Court of the European Union on 1 August 2025, following the rejection by the Court of Justice of the European Union of an appeal lodged by the French government in support of the European Commission. Manufacturers are therefore no longer legally required to apply this harmonised classification.

Additional data requested on potential respiratory toxicity under REACH

ANSES is also responsible for assessing the hazards and risks of TiO2 for human health and the environment under the European REACH Regulation on the registration, evaluation, authorisation and restriction of chemicals. Titanium dioxide has been included in the Community rolling action plan (CoRAP) due to concerns about its potential carcinogenic and mutagenic properties.

Following ANSES's assessment of TiO2 under this regulation, manufacturers producing TiO2 are currently carrying out toxicology studies into the mechanisms of action involved in the respiratory toxicity of 13 forms (nano or micro) of TiO2. The titanium dioxide industry consortium must provide these additional data to the Agency by the end of 2026. On this basis, if justified by the data produced, additional studies of repeated inhalation toxicity may be carried out.

Threshold values to protect the general population and workers

In order to address the challenges of managing industrial facilities and sites in France, ANSES was asked to define a chronic toxicity reference value (TRV) by inhalation for nanoscale TiO2. This is the first TRV developed for a nanomaterial in France. The Agency recommended a long-term TRV by inhalation of 0.12 µg.m-3 for the P25 form of TiO2. This value is designed to prevent lung inflammation. Following on from this work and to strengthen risk prevention in the workplace, ANSES recommended an occupational exposure limit over 8 hours (8h-OEL) of 0.8 µg.m-3 for nanoparticulate TiO2. It also recommended not exceeding the concentration of 4 µg.m-3 over a 15-minute period, in order to limit the size and number of exposure peaks over the working day. Lastly, the Agency recommended developing and validating methods for monitoring concentrations of nanoparticulate TiO2 in the workplace.

Assessment of the safety of TiO2 in cosmetics

TiO2 is a cosmetic ingredient authorised as a colorant and UV filter. Its uses are governed by Annexes III (colorants) and VI (UV filters) of  Regulation (EC) No 1223/2009 (the European Cosmetics Regulation). Following concerns expressed by EFSA about its potential genotoxicity, the European Commission asked its Scientific Committee on Consumer Safety (SCCS) to reassess its safety. In 2024, the SCCS concluded that it was not possible to rule out a potential genotoxic effect of most forms of TiO2 used in cosmetics. This assessment was subject to a public consultation, during which ANSES submitted comments supporting the conclusions of the SCCS on the need for additional data to be able to reach a conclusion about whether cosmetic products containing TiO2 are safe to use.

In response to the SCCS's assessment, in May 2024 a group of manufacturers shared a roadmap with the Member States and the European Commission, proposing an approach for providing additional data. This was mainly based on an approach that groups the different forms of TiO2 according to their physico-chemical characteristics. ANSES was asked to analyse this proposal by the Directorate General for Health (DGS) and the Directorate General for Competition Policy, Consumer Affairs and Fraud Control (DGCCRF). It identified some methodological weaknesses and recommended in particular taking account of parameters other than just the physico-chemical characteristics proposed by manufacturers. The Agency also stressed the importance of demonstrating the representativeness of the grades chosen for testing. However, the Agency's conclusions do not prejudge any assessment that may be carried out by the SCCS.

Funding of research

As part of its National Research Programme for Environmental and Occupational Health (PNR EST), ANSES funds projects aimed at acquiring knowledge about the health effects of TiO2. The results are currently being published in order to share them with the scientific community.

Monitoring and assessing nanomaterials

Nanoscale TiO2 is one of the four most widely produced and imported nanomaterials in France. ANSES manages the annual reporting register for nanomaterials (R-Nano), which lists the various uses of nanoscale substances. The Agency has conducted several studies on nanomaterials, whether on risk assessment or the adoption of a common definition for all industry sectors.

Expert appraisals that contributed to it being banned as a food additive

The food additive E171, used for its colouring and opacifying properties, contains particles of titanium dioxide. Between 2017 and 2022, ANSES carried out several expert appraisals on the risks associated with its ingestion. Each of these concluded that it was not possible to resolve the uncertainties regarding the safety of the additive E171. Some research results suggest that TiO2 may promote the development of cancer or be genotoxic, but the available data are not sufficiently robust to be able to rule on the toxicity of the food additive. These uncertainties led to its use in foodstuffs being suspended in France in January 2020 and banned in the European Union in January 2022 following an assessment by the European Food Safety Authority (EFSA). 

Proposal to classify the substance as carcinogenic by inhalation

In 2015, ANSES submitted a request to the European Chemicals Agency (ECHA) to classify TiO2 as a presumed carcinogen by inhalation (Category 1B) under the CLP Regulation on the classification, labelling and packaging of dangerous substances and mixtures. According to ANSES, based on several studies, TiO2 is a proven carcinogen by inhalation for animals.

In 2017, ECHA's Committee for Risk Assessment concluded that TiO2 in all its forms should be classified as a suspected human carcinogen (Category 2) by inhalation[JA2] . In 2019, this decision was ratified by the European Commission, obliging manufacturers to inform workers of the risks involved in handling products containing TiO2, through the use of appropriate labelling.

However, this classification was challenged by manufacturers and annulled by the General Court of the European Union on 1 August 2025, following the rejection by the Court of Justice of the European Union of an appeal lodged by the French government in support of the European Commission. Manufacturers are therefore no longer legally required to apply this harmonised classification.

Additional data requested on potential respiratory toxicity under REACH

ANSES is also responsible for assessing the hazards and risks of TiO2 for human health and the environment under the European REACH Regulation on the registration, evaluation, authorisation and restriction of chemicals. Titanium dioxide has been included in the Community rolling action plan (CoRAP) due to concerns about its potential carcinogenic and mutagenic properties.

Following ANSES's assessment of TiO2 under this regulation, manufacturers producing TiO2 are currently carrying out toxicology studies into the mechanisms of action involved in the respiratory toxicity of 13 forms (nano or micro) of TiO2. The titanium dioxide industry consortium must provide these additional data to the Agency by the end of 2026. On this basis, if justified by the data produced, additional studies of repeated inhalation toxicity may be carried out.

Threshold values to protect the general population and workers

In order to address the challenges of managing industrial facilities and sites in France, ANSES was asked to define a chronic toxicity reference value (TRV) by inhalation for nanoscale TiO2. This is the first TRV developed for a nanomaterial in France. The Agency recommended a long-term TRV by inhalation of 0.12 µg.m-3 for the P25 form of TiO2. This value is designed to prevent lung inflammation. Following on from this work and to strengthen risk prevention in the workplace, ANSES recommended an occupational exposure limit over 8 hours (8h-OEL) of 0.8 µg.m-3 for nanoparticulate TiO2. It also recommended not exceeding the concentration of 4 µg.m-3 over a 15-minute period, in order to limit the size and number of exposure peaks over the working day. Lastly, the Agency recommended developing and validating methods for monitoring concentrations of nanoparticulate TiO2 in the workplace.

Assessment of the safety of TiO2 in cosmetics

TiO2 is a cosmetic ingredient authorised as a colorant and UV filter. Its uses are governed by Annexes III (colorants) and VI (UV filters) of  Regulation (EC) No 1223/2009 (the European Cosmetics Regulation). Following concerns expressed by EFSA about its potential genotoxicity, the European Commission asked its Scientific Committee on Consumer Safety (SCCS) to reassess its safety. In 2024, the SCCS concluded that it was not possible to rule out a potential genotoxic effect of most forms of TiO2 used in cosmetics. This assessment was subject to a public consultation, during which ANSES submitted comments supporting the conclusions of the SCCS on the need for additional data to be able to reach a conclusion about whether cosmetic products containing TiO2 are safe to use.

In response to the SCCS's assessment, in May 2024 a group of manufacturers shared a roadmap with the Member States and the European Commission, proposing an approach for providing additional data. This was mainly based on an approach that groups the different forms of TiO2 according to their physico-chemical characteristics. ANSES was asked to analyse this proposal by the Directorate General for Health (DGS) and the Directorate General for Competition Policy, Consumer Affairs and Fraud Control (DGCCRF). It identified some methodological weaknesses and recommended in particular taking account of parameters other than just the physico-chemical characteristics proposed by manufacturers. The Agency also stressed the importance of demonstrating the representativeness of the grades chosen for testing. However, the Agency's conclusions do not prejudge any assessment that may be carried out by the SCCS.

Funding of research

As part of its National Research Programme for Environmental and Occupational Health (PNR EST), ANSES funds projects aimed at acquiring knowledge about the health effects of TiO2. The results are currently being published in order to share them with the scientific community.

Monitoring and assessing nanomaterials

Nanoscale TiO2 is one of the four most widely produced and imported nanomaterials in France. ANSES manages the annual reporting register for nanomaterials (R-Nano), which lists the various uses of nanoscale substances. The Agency has conducted several studies on nanomaterials, whether on risk assessment or the adoption of a common definition for all industry sectors.