It Is Justified By EFSA
As GIMDES, we have not been allowing the use of “Titanium Dioxide (E171)” because of its harmful effects on the health system and we have not been certifying products with TD.
Albeit years later, EFSA (European Food Safety Agency) concluded that titanium dioxide can no longer be considered as a safe food additive, and has made relevant updates on titanium dioxide as of May 6, 2021.
In its 2016 opinion, the ANS Panel recommended new studies be carried out to fill the gaps on possible effects on the reproductive system, which could enable them to set an Acceptable Daily Intake (ADI). Uncertainty around the characterisation of the material used as the food additive (E 171) was also highlighted, in particular with respect to particle size and particle size distribution of titanium dioxide used as E 171.
In 2019, EFSA published a statement on the review of the risk related to the exposure to food additive titanium dioxide (E171) performed by the French Agency for Food, Environment and Occupational Health Safety (ANSES). In its statement, EFSA highlighted that the ANSES opinion reiterated the uncertainties and data gaps previously identified by EFSA and did not present findings that invalidated the Authority’s previous conclusions on the safety of titanium dioxide.
In the same year (2019), the Netherlands Food and Consumer Product Safety Authority (NVWA) also delivered an opinion on possible health effects of food additive titanium dioxide, which highlighted the importance of examining immunotoxicological effects in addition to potential reprotoxicological effects.
After conducting a review of all the relevant available scientific evidence, EFSA concluded that a concern for genotoxicity of TiO2 particles cannot be ruled out. Based on this concern, EFSA’s experts no longer consider titanium dioxide safe when used as a food additive. This means that an Acceptable Daily Intake (ADI) cannot be established for E171. 
Alhamdulillah, realizing possible hazardous effects of titanium dioxide, long years before, GIMDES has decided not to issue Halal and Tayyib certificate for titanium dioxide and the products using it.
We pray Allah (SWT) keep us on His true path while providing Halal and Tayyib certification services.