Registration Dossier

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Please be aware that this old REACH registration data factsheet is no longer maintained; it remains frozen as of 19th May 2023.

The new ECHA CHEM database has been released by ECHA, and it now contains all REACH registration data. There are more details on the transition of ECHA's published data to ECHA CHEM here.

Diss Factsheets

Environmental fate & pathways

Endpoint summary

Administrative data

Description of key information

A review of the structure of the test item has indicated that it consists of infinite (polymeric) chains of B2O42- units plus the Ca2+ counterions, and therefore, will be extremely insoluble in water. Therefore, it has been concluded that any test item that appears to have dissolved in aqueous solutions will actually exist in the solutions as the fully hydrolysed (i.e., polymeric B2O42- chains into borate) and fully dissociated species, i.e. as separate calcium cations and borate (boric acid) anions, depending on the pH of the aqueous solution.

Based on the dissociation constant of boric acid, i.e. 9.14 it can be concluded that hydrolysis and therefore apparent solubility of the test item at pH 9 will be slow and minimised. Hydrolysis and apparent solubility at pH 7 will be fairly rapid. Hydrolysis and apparent solubility at pH 4 will be very rapid and maximised.

Based on the extreme insolubility of the (parent) test item in water and the hydrolysis issues discussed above, it was concluded that hydrolysis testing of the (parent) test item was not feasible.

Additional information