Registration Dossier

Administrative data

Key value for chemical safety assessment

Effects on fertility

Additional information

Due to rapid hydrolysis of TiOSO4 in contact with wet material to produce final hydrolysis products TiO2 and H2SO4, the final hydrolysis products are the relevant potentially toxic species.

The absorbance of TiO2 from the gastro-intestinal tract has been shown to be below the limit of detection in a toxicokinetic study in rats (Landford-Pollard 2003). Similar results are to be expected for absorption via the respiratory route. Therefore the exposure of progeny towards titanium species stemming from TiOSO4 exposure is deemed negligible.

As the pH effects resulting from sulphuric acid are not of relevance for this assessment, the hazard characterisation shall be based on the other final hydrolysis product titanium dioxide.

Based on column 2 of the table given in REACH Annex IX, the study on reproduction toxicity needs not to be conducted if the substance has been proven to have little toxic activity. This is deemed to be the case for titanium dioxide, as demonstrated in the other toxicity sections of the dossier.

This assessment is in line with the assessments of the potential of the two hydrolysis products to cause reproductive toxicity or teratogenicity:

Citation from the TiO2 REACH dossier: “Based on the weight of evidence from the available long-term toxicity/carcinogenicity studies in rodents and the relevant information on the toxicokinetic behaviour in rats it is concluded that TiO2 does not present a reproductive toxicity hazard.” Based on this information, neither target compound TiOSO4, nor the final hydrolysis products TiO2 and H2SO4 are deemed to have any potential to cause developmental toxicity, teratogenicity or effects on fertility.

Based on these grounds further testing is scientifically unjustified.


Short description of key information:
The conduct of reproduction toxicity studies direct on the unstable target compound titanium oxide sulphate is technically not feasible. Read-across with studies on the final hydrolysis products titanium dioxide and sulphuric acid is being proposed. Conduct of studies is waived as titanium dioxide has been proven to have little toxic activity. Based on the knowledge available, neither target compound TiOSO4, nor the final hydrolysis products TiO2 and H2SO4 are deemed to have any potential to cause developmental toxicity, teratogenicity or effects on fertility.

Effects on developmental toxicity

Description of key information
Neither target compound TiOSO4, nor the final hydrolysis products TiO2 and H2SO4 are deemed to have any potential to cause developmental toxicity, teratogenicity or effects on fertility. 
Additional information

See discussion above (Effects on fertility).

Justification for classification or non-classification

Neither target compound TiOSO4, nor the final hydrolysis products TiO2 and H2SO4 are deemed to have any potential to cause developmental toxicity, teratogenicity or effects on fertility. Based on this no classification of target substance TiOSO4 is warranted.

Additional information