Titanium dioxide has been approved for use in Europe for a century, with studies repeatedly showing no harmful effects to the public or workers.
Titanium dioxide (TiO2) is a vital and important ingredient in hundreds of products, including paints, plastics, inks, papers, cosmetics, pharmaceuticals and food. Its varied properties mean it can be used in many ways, for example as a vibrant white colourant, to protect from UV radiation, and to reduce pollution.
It has been used safely for around 100 years in a staggering number of products. It has a history of regulatory approval, with thorough and continuous scientific assessment of its uses and production.
- TiO2 is derived from one of the most abundant natural materials on earth and its chemically stable state provides a base for its safe use in numerous applications.
- European regulators have consistently approved its use in paints and other coatings, plastics, food, cosmetics, and other everyday products.
- Several long-term studies on workers with regular exposure to titanium dioxide showed no harmful effects.
TiO2 is one of the most versatile compounds in the world, found in an extraordinarily diverse range of products and technologies we see and use every day, including paint, plastics, cosmetics, sunscreens, food, glass, and even catalytic converters.
TiO2 has been assessed for safety by a large number of regulatory authorities and has consistently been found safe for all its intended applications.
Over the years, however, its omnipresence has led to questioning and research to determine whether it has any impact on our health, as well as any associated side effects linked to exposure. This concern is particularly the case in relation to its use within the food and cosmetic industries.
Is titanium dioxide safe for consumers?
Sourced from one of the most common elements on earth, titanium dioxide (TiO2) has been consistently confirmed by a large number of regulatory bodies to be a nontoxic, inert, and safe material.
Its vibrant white colour makes it an ideal substance for many of its uses, and its nontoxicity makes it safe for those who use or benefit from these products. It is also safely used as a colourant and thickener in food and cosmetics, as there are near to no instances of allergy or intolerance associated with its consumption or application.
In September 2016, the European Food Safety Authority’s (EFSA) Scientific Panel on Food Additives and Nutrient Sources published an Opinion confirming TiO2 is considered safe for use in food.
It is also approved for use in a variety of products and materials, including sunscreen, toothpaste and pharmaceuticals.
Risks from inhalation
Any concerns raised about the safety of TiO2 are predominantly about risks from inhalation of TiO2 in powder form, which are based solely on the study of inhalation exposure studies in rats, showing lung overload conditions. In commentary from industry experts and extensive third-party studies, there has been no robust evidence to suggest TiO2 is harmful to humans.
The International Agency for Research on Cancer (IARC) has suggested titanium dioxide inhalation is “possibly carcinogenic to humans” (Group 2B) on the basis of limited research carried out on rats and in one study using very high dose levels. The rats used in the study suffered the effects of ‘lung overload’ something not seen in other species studied, or in humans.
The IARC conclusion was based on three rat studies; it found no association between human exposure to titanium dioxide and cancer risk in the human studies reviewed.
One animal study, carried out in 2005, exposed rats to intratracheal administration of titanium dioxide, that is, using a suspension fed into the animals breathing system. The other two studies (two others reviewed had negative findings) were carried out in 1985-1986 and 1995. The studies positive findings were the result of exposing rats to relatively high levels of titanium dioxide via inhalation for an extended period of time.
Organisation for Economic Cooperation and Development (OECD) guidelines, for testing chemicals on animals, have since been updated. For example, new guidelines for texting acute inhalation toxicity were adopted in 2009. The methods used in the earlier rat studies do not meet up-to-date testing guidelines now used in the EU.
On 9 June 2017, the Committee for Risk Assessment (RAC) of the European Chemicals Agency (ECHA) proposed that TiO2 should be classified as a suspected carcinogen (cat. 2). The RAC did not accept all the data used by IARC but still reached the draft classification opinion based on the observations seen in rats, exposed to very high levels of TiO2.
The RAC opinion goes against a vast body of scientific evidence that does not support a classification of TiO2 for humans, which is supported by over 50 years of epidemiological data on more than 24,000 workers and demonstrates there is no link between cancer in humans and exposure to titanium dioxide.
Additionally, as titanium dioxide tends to be fully incorporated into the end product, potential consumer exposure to TiO2 in powder form is extremely low.
Click here for more information on cancer and titanium dioxide.
Is titanium dioxide production safe?
In nature, titanium is often associated with other common elements such as iron. Two methods are used to separate these substances to form pure TiO2: a sulphate process and a chloride process.
The same production processes are used to manufacture titanium metals for the aerospace, medical, shipbuilding, and construction industries. As with all chemical processes, both TiO2 methods employ and adhere to stringent health, safety, and handling standards.
The manufacture of titanium dioxide is optimised to recycle or reuse raw materials. Typically, chlorine and sulphuric acid are recycled and iron is converted into valuable co-products.
TiO2 production is regulated via EU-wide standards and leading producers in Europe also comply with Responsible Care® codes.
Responsible Care® helps ensure sustainable production and improvements to how TiO2 is manufactured. Life Cycle Assessment has been carried out to measure the environmental impact of manufacturing titanium dioxide.
Find out more about the sustainability measures.
Is TiO2 safe for workers?
Current evidence shows that workers at titanium dioxide manufacturing plants such as those in the EU, which follow standard occupational health and safety requirements, should not be concerned about TiO2 exposure.
In addition to national bodies, which monitor the substances being used in their respective countries, the European Union’s REACH legislation monitors the safety of all chemicals being used. This requires industries to assess any hazards and manage any potential risks related to those substances.
In its registration of TiO2 under REACH, the industry gathered and assessed all available scientific data on TiO2 and determined that there was no evidence of hazard according to the REACH evaluation criteria.
TiO2 production is carefully managed by the industry. Producers take all necessary measures to comply with EU and member state laws and regulations for the safe handling of materials used in the manufacturing of TiO2.
Moreover, titanium dioxide has been commercially available for around 100 years. Over this period, extensive studies of workers in the TiO2 manufacturing industry have found no evidence of an increased risk of lung problems.
Four large epidemiology studies in North America and Europe, involving more than 24,000 workers in the titanium dioxide manufacturing industry, indicated no association with increased risk of cancer or with any other adverse effects from exposure to TiO2.
Is titanium dioxide safe in food?
The European Food Safety Authority (EFSA) oversees the food industry – issuing each additive with a unique ‘E’ number and setting safe daily consumption limits. It lists titanium dioxide as E171.
The effectiveness of TiO2 as a whitener to enhance and brighten colour and its high opacity makes E171 a popular additive in food. In 2016, the EFSA’s Scientific Panel on Food Additives and Nutrient Sources published an Opinion confirming TiO2 is considered safe for use in food.
When used as a food additive, food-grade titanium dioxide consists mainly of larger particles. It is only in this size that producers benefit from its white colour and opacity properties. Smaller particles (nanoparticles) are transparent and have no colorant properties.
A characteristic of TiO2 is that, in practice, nano-size particles bind together to form larger particles. Given the low addition levels of E171 in food, the proportion of particles that may actually be nano size is likely to be very low.
E171 was recently subject to a thorough re-evaluation by the European Food Safety Authority (EFSA) as part of a comprehensive investigation into the food colours permitted for use in the European Union prior to 2009. Based on recent scientific information, TiO2 was found to be safe to use.
In fact, when used in food and pharmaceutical packaging, such as milk containers or medicine vials, TiO2 protects the products by shielding them from daylight, including UV light and the associated degradation processes.
Discover more about the use of titanium dioxide in food.
Future regulation of titanium dioxide
In May 2016, the French food safety agency ANSES requested that titanium dioxide be categorised as a 1B carcinogen (possibly carcinogenic to humans). In its proposal, the agency cited the same research on rats (mentioned earlier) as evidence of the potential harmful effects (on humans) of titanium dioxide.
In considering the ANSES proposal, ECHA carried out a consultation. More than 500 responses were received during the public consultation; this was a very large number of responses, with the overwhelming view that titanium dioxide is safe and that no such classification was needed.
The consultation and review period has now finished, with the ECHA Committee for Risk Assessment (RAC) concluding that titanium dioxide met criteria to be classified under a less severe category (2), based on inhalation. This is despite the body of scientific evidence and the views of hundreds of respondents to the consultation, indicating no such classification is needed.
The European Commission will now evaluate the opinion and decide what, if any, regulatory measures will be taken.
Scientific assessments carried out by the industry, as outlined in the REACH dossier, and further supported by the comments submitted in the public consultation, demonstrate ‘no classification’ is needed for the substance, in all its forms.
With a legacy of around 100 years of safe production and commercial use across a vast number of industries, titanium dioxide has brought major benefits to society, with no harmful effects on people or the environment.
Long-term studies have shown that the consumption, usage and production of titanium dioxide do not harm human beings and many regulatory bodies have classed it non-toxic and non-carcinogenic to humans.
Visit What is titanium dioxide? to find more information.
-  What is titanium dioxide?
-  What is titanium dioxide? (from page 193)
-  About titanium dioxide
-  IARC Monographs on the Evaluation of Carcinogenic Risks to Humans (pages 225-227 and page 273)
-  OECD guideline for the testing of chemicals
-  Analysis of the Simplification of the Titanium Dioxide Directives
-  Titanium dioxide
-  Epidemiologic study of workers exposed to titanium dioxide
-  Food colours: titanium dioxide marks re-evaluation milestone
-  Titanium dioxide nanoparticles in food (additive E171)
-  Comments and response to comments on CLH: Proposal and justification
-  Harmonised classification and labelling previous consultations
-  What it titanium dioxide?