Titanium dioxide should remain classified as carcinogenic within the EU—despite industry interference.
Titanium dioxide (TiO2), often used for its whitening capacity and found in daily products such as sunscreens and cosmetics, is suspected of causing cancer. But the hazard classification of the substance as a suspected carcinogen has been a long and winding road, with the scientific and political battle culminating in a legal row at the European Union’s highest court—to the detriment of citizens and workers.
TiO2 is widely used in industrial and consumer goods, including hairspray and lipstick. It was however recently banned as a food additive by the European Commission. And as the body of scientific evidence of potential harm via oral exposure continues to grow, TiO2 is increasingly being removed voluntarily from products such as toothpaste and medicines.
After a thorough scientific assessment by the European Chemicals Agency (ECHA), in 2020 TiO2 was classified as a suspected carcinogen, when used in certain powder forms, under the EU regulation for classification, labelling and packaging of substances and mixtures (CLP). That does not mean a ban: the purpose of the CLP hazard classification is to inform workers and the public about the danger(s) of a substance or mixture, via warning and labelling, and provide guidance for protective measures to be taken by workers and consumers.
After years of aggressive industry lobbying to avoid this classification—essential adequately to inform those handling the substance—several manufacturers however took the matter to court. In a disappointing turn of events, the EU General Court of Justice annulled the classification last year.
Why did the court rule in favour of the industry’s arguments? Its reasoning was that the study used for the classification was not sufficiently reliable and that carcinogenicity was not an intrinsic property of TiO2, because particles were found to be carcinogenic ‘only’ in powder form.
This was though in contradiction to the scientific opinion of ECHA’s Risk Assessment Committee—which recognised the relevance of the physico-chemical characteristics of a substance (here the powder form) for a hazard classification. Both France and the commission have appealed the court’s decision, so the story is not over.
Troubling trend
Lessons can however be drawn on the effect of industry interference on evidence-based decision-making. The case of TiO2 is not isolated and indeed reveals a troubling trend, whereby powerful industry players, having already invested huge resources to hamper essential protective regulation, turn to the courts when they do not get their way.
This is notably the case for hazard classifications under the CLP regulation. But it also applies to identifications of substances of very high concern (SVHC) under the REACH regulation (for instance, bisphenol A), as well as to non-approvals or non-renewals of active substances in pesticides—such as the recent non-renewal of the genotoxic and neurotoxic chlorpyrifos-methyl, although in the end that was upheld by the court.
The multiplication of such costly legal processes is not only meant to intimidate regulators taking protective actions on chemicals of concern. It also takes its toll on the uptake of independent science in regulatory contexts by systematically challenging the evidence base. This costs the EU institutions and member states significant resources and precious time—which could otherwise be allocated to accelerating regulatory assessments and actions, to match the scientifically established emergency to address chemical pollution.
Urgency of reform
We are once again left with the importance and urgency of reforming the chemicals legislative framework, starting with CLP and REACH. Core principles—‘no data, no market’, the burden of proof on industry, the ‘polluter pays’ and precaution—must be enacted to untap the full protective potential of these cornerstone pieces of law.
Yet while CLP reform is well under way and is expected to help classify substances of concern more quickly, more efficiently and more protectively, the REACH revision has been postponed and will not see the light of day in this mandate. Candidate MEPs should make the overhaul of chemical-safety assessment and regulation a priority for the next term, after the elections in June, so that Europe plays its part in alleviating the burden of chemical pollution on our environment and our health.
If one lesson is to be learnt from the TiO2 classification limbo, it is that we urgently need reformed CLP and REACH regulations to allow stricter, more timely and better hazard classifications and subsequent restrictions of such substances of concern in the future. There is no justification for keeping European citizens exposed to harmful substances—including potential carcinogens—in the dark.
