Registration Dossier

Administrative data

Description of key information

According to REACH Regulation (EC) No. 1907/2006, Annex VII, column 2, and Guidance Chapter R7a, a study on skin irritation/corrosion and eye corrosion/irritation does not need to be conducted if the available information indicates that the criteria are met for classification as corrosive. Since titanium oxide sulphate releases sulphuric acid when in contact with wet materials, no testing required.

Key value for chemical safety assessment

Skin irritation / corrosion

Endpoint conclusion
Endpoint conclusion:
adverse effect observed (corrosive)

Eye irritation

Endpoint conclusion
Endpoint conclusion:
adverse effect observed (irritating)

Additional information

Titanium oxide sulphate is hydrolyses immediately when in contact with wet materials.

TiOSO4 + H2O↔TiO2 + H2SO4

The hydrolysis reaction proceeds when the resulting sulphuric acid is being neutralised. Therefore, under physiologically and environmentally relevant conditions titanium oxide sulphate hydrolyses rapidly according to above stated reaction to sulphuric acid and to titanium dioxide.

Skin and eye corrosion:

Sulphuric acid, which is produced as a product of hydrolysis, eventually accounts for the corrosive character of target chemical titanium oxide sulphate. Sulphuric acid≥ 15% is labelled as C; R35 under Directive 67/548/EEC, and as Skin corr. 1A, H314 "Causes severe skin burns and eye damage" under CLP, regulation 1272/2008.

No data available on respiratory irritation, however neither sulphuric acid nor titanium dioxide are noted to cause respiratory irritation effects.


Effects on skin irritation/corrosion: corrosive

Effects on eye irritation: corrosive

Effect level: empty Endpoint conclusion: Adverse effect observed

Justification for classification or non-classification

Discussions on skin corrosion classification:

According to the harmonised classification and labelling, Annex VI of Regulation 1272/2008 (016 -020 -00 -8), sulphuric acid is subject to harmonised classification as Skin Corr. 1A H314 if c(H2SO4) ≥ 15%. As sulphuric acids results from hydrolysis of target chemical titanium oxide sulphate in eqimolar amounts, classification as skin Corr. 1A H314 applies to titanium oxide sulphate solutions containing c(TiOSO4) ≥ 15%. In case 5%≤ c(TiOSO4) <15%, Skin irrit. 2 H315 and Eye irrit. 2 H319 would apply. No classification necessary if c(TiOSO4) < 5%.

No data available on respiratory irritation, however neither sulphuric acid nor titanium dioxide are noted to cause respiratory irritation effects.

Proposed classification and labelling for titanium oxide sulphate acc. to CLP Regulation 1272/2008 (classification based on the fact that sulphuric acid results in equimolar amounts from the hydrolysis of target chemical titanium oxide sulphate when getting in contact with wet materials):

Hazard class and code in case c(TiOSO4) = c(H2SO4) ≥ 15%:

Skin Corr. 1A, H314

Labelling: GHS05, Danger

Hazard class and code in case c(TiOSO4) = c(H2SO4) < 15% but ≥ 5 %

Skin Irrit. 2, H315

Labelling: GHS07, Warning

Proposed classification and labelling for titanium oxide sulphate according to Directive 67/548/EEC (classification based on the fact that sulphuric acid results in equimolar amounts from the hydrolysis of target chemical titanium oxide sulphate when getting in contact with wet materials):

Hazard class and code in case c(TiOSO4) = c(H2SO4) ≥ 15%:

Corrosive, R35

Labelling: C and R35

Hazard class and code in case c(TiOSO4) = c(H2SO4) < 15% but≥ 1 %:

Irritating, R38

Labelling: Xi and R38

Hydrolysis of titanium oxide sulphate produces sulphuric acid, which is sufficient to justify the classification of target chemical titanium oxide sulphate. This conclusion is confirmed by test results and by accidental human exposure.