The regulatory study found some products contained carcinogens and toxic ingredients.
Nearly 300 samples of tooth whitening products have been found to be non-compliant with European Union cosmetic regulations.
The tooth whiteners and whitening strips were assessed in a Market Surveillance Study by the European Directorate for the Quality of Medicines and HealthCare (EDQM).
According to the survey, nearly 80% of brush-on whiteners and more than 50% of tray-based teeth whiteners were at fault.
The issues concerned included hydrogen peroxide content, which was higher than permitted and the presence of a CMR substance, which was classified as carcinogenic, mutagenic or toxic for reproduction.
As well as non-compliant ingredients, several products tested were found not to be registered in the Cosmetics Products Notification Portal (CPNP) and some were incorrectly labelled, despite most products being manufactured in European countries.
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