Barium titanium trioxide

Endpoint summary

Description of key information

skin irritation
read-across, in vivo, rabbit: not irritant (GLP, OECD Draft Proposal for a new guideline; Verbaan, 2010)
eye irritation
in vivo, rabbit: not irritant (GLP, OECD 405; TÜV SÜD PSB, 2012)
respiratory irritation
no data available

Key value for chemical safety assessment

Skin irritation / corrosion

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed (not irritating)

Eye irritation

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed (not irritating)

Respiratory irritation

Endpoint conclusion

Endpoint conclusion:

no study available

Additional information

There are reliable studies available to assess the potential of the analogous test substance for skin irritation and

to assess the potential of the test substance for eye irritation.

For read-across barium chloride is adopted as it is also an inorganic barium salt whose relevant toxicological nature depends on the common cation barium whereas the toxicological nature of the anion is negligible. The substances differ in solubility. Barium chloride is soluble while barium titanium trioxide is slightly soluble. But this difference is considered as negligible as it is supported by the absence of any adverse findings in acute toxicity for the analogue substance. In conclusion, read-across for the endpoint irritation is justified.

Skin irritation

A draft guideline in vitro study using Reconstructed human Epidermis (RhE) was used to assess the acute skin irritation of the analogous test substance barium chloride dihydrate (CAS no 10326-27-9) (purity: 100.6 %). The test substance was incubated on a total of three tissues. Skin irritation is measured using cell viability as read out. Cell viability is measured by enzymatic conversion of the vital dye MTT into a blue formazan salt which is quantitatively measured after extraction from tissues. The amount of extracted formazan was determined spectrophotometrically at 570 nm. Cell viability was calculated for each tissue as a percentage of the mean of the negative control tissues. The relative mean tissue viability obtained after 15 minutes treatment with barium chloride dihydrate compared to negative control tissue was 80 %. Since the mean relative tissue viability for barium chloride dihydrate was above 50 % (the defined threshold level for identification of irritants) barium chloride dihydrate is considered to be non-irritant.

 

Under the test conditions chosen the test substance barium chloride dihydrate does not show a skin irritation potential in the in vitro skin irritation test.

Eye irritation

 

To assess the acute eye irritation/corrosion three female New Zealand White rabbits were treated with the test substance barium titanium trioxide (purity: > 99 weight-%) according to OECD guideline 405 (TÜV SÜD PSB, 2012). An amount of 0.1 g of the test substance was applied to one eye of each rabbit (stepwise procedure starting with one animal and supplementing two additional animals). About one hour after application the eye was rinsed with saline. The ocular reactions were assessed approximately 1, 24, 48 and 72 hours after application. Some blood vessels hyperaemic (injected) were observed one hours after application. No other adverse effects were observed during the observation period. The ocular reactions were reversible in all animals within 24 hours after application.

The average score (24 to 72 hours) for irritation was calculated to be 0.0 for corneal opacity, iris, chemosis and conjunctival redness.

 

Considering the described ocular reactions as well as the average score for irritation, barium titanium trioxide does not show an eye irritation potential under the test conditions chosen.

Justification for classification or non-classification

Classification, Labeling, and Packaging Regulation (EC) No. 1272/2008:

Based on the results, the classification of the test substance for skin and eye irritation under Regulation 1272/2008 is not warranted.