Reaction products of boric acid and lithium hydroxide

Endpoint summary

Description of key information

Based on the available in vivo test data for analogous substances which indicate an absence of skin sensitising effect, an absence of evidence from widespread consumer and occupational use of inorganic borates and very low dermal penetration, it can be concluded that all lithium borates are unlikely to cause sensitisation by skin contact.

Key value for chemical safety assessment

Skin sensitisation

Link to relevant study records

Reference

Endpoint:

skin sensitisation, other

Type of information:

read-across based on grouping of substances (category approach)

Adequacy of study:

weight of evidence

Justification for type of information:

A literature review of available data which is considered relevant to dilithium tetraborate was conducted to ascertain the potential for skin sensitisation effects.

At physiological pH, the substances dissociate and release boric acid and lithium ions as a result of relevant transformation pathways. The literature review looked at a range of borate substances including boric acid, disodium tetraborate anhydrous, disodium tetraborate pentahydrate and disodium tetraborate decahydrate which reported no signs of skin sensitisation. Data collected in the weight of evidence report also noted that it is unlikely that the lithium cation would cause sensitisation by skin contact. As lithium tetrahydroxyborate will dissociate to the same common compounds, then the weight of evidence report can also be used to cover the sensitisation endpoint for the REACH registration of the UVCB-Reaction products of boric acid and lithium hydroxide.

Key result

Remarks on result:

other: Weight of evidence approach

Remarks:

This is a weight of evidence which is based on different types of data which are considered relevant to the assessment of the likelihood of skin sensitising effects.

Interpretation of results:

GHS criteria not met

Conclusions:

Based on the available in vivo test data for analogous substances which indicate an absence of skin sensitising effect, an absence of evidence from widespread consumer and occupational use of inorganic borates and very low dermal penetration, it can be concluded that all lithium borates are unlikely to cause sensitisation by skin contact.

Executive summary:

A literature review of available data which is considered relevant to dilithium tetraborate was conducted to ascertain the potential for skin sensitisation effects. At physiological pH, the lithium borates dissociate and release boric acid and lithium ions as a result of relevant transformation pathways. The literature review looked at a range of borate substances including boric acid, disodium tetraborate anhydrous, disodium tetraborate pentahydrate and disodium tetraborate decahydrate which reported no signs of skin sensitisation.  Data collected in the weight of evidence report also noted that it is unlikely that the lithium cation would cause sensitisation by skin contact. As the UVCB-Reaction products of boric acid and lithium hydroxide will dissociate to the same common compounds as dilithium tetraborate, then the weight of evidence report can also be used to cover the sensitisation endpoint for the REACH registration of the UVCB-Reaction products of boric acid and lithium hydroxide. Classification as a skin sensitiser is therefore not required.

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed (not sensitising)

Justification for classification or non-classification

Based on the available in vivo test data for analogous substances which indicate an absence of skin sensitising effect, an absence of evidence from widespread consumer and occupational use of inorganic borates and very low dermal penetration, it can be concluded that all lithium borates are unlikely to cause sensitisation by skin contact.