The SCCS has concluded that MBBT is of no concern when applying the substance dermally, at the nanoscale.
However, the EC appointed Committee did find that some aspects of the substance requires further investigation, including possible irritation effects via a cosmetovigilance programme and identification of the substance in selected tissues to monitor for potential bioaccumulation, given its lipophilicity.
MBBT is also known to be toxic to the aquatic environment, and use of the substance in sunscreen could thus lead to environmental exposure. The SCCS also stated that no conclusion can be drawn with regard to the genotoxity of the substance due to lack of data.
Impurities of the MBBT
According to the document, typical impurities of MBBT were determined by means of HPLC-DAD and HPLC-MS with the concentration limit for the determination of impurities set to 0.08 per cent (area/area).
The SCCS looked at known impurities and possible impurities which could come from the last steps of synthesis and also assessed volatile impurities by means of thermo-desorption coupled with GC/MSD.
"In this chemical characterisation study, only one relevant impurity peak was detected by HPLC and identified as an isomer of the UV-absorbing ingredient.The volatile impurities Isopropanol, Dibutylamine, Xylene (mixture of ortho-, meta- and para-isomers) and formaldehyde were identified and shown to have a concentration in or below the ppm range."
The opinion is open for public comment until 26 April here.
Committee kept busy of late
Of late, the European Commission has been keeping the SCCS busy determining the safety/risk of certain hair dye and cosmetic ingredients before putting forward for public comment.
At its most recent plenary meeting, the Committee gave the opinion that the current data on hair dye ingredient 2,6-diaminpyridine was insufficient to assess its safety in consumer products.
More information has now been collected, and the European Commission has requested the Committee reconsider the safety of the substance for use in consumer hair dye products.