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Diss Factsheets

Administrative data

Endpoint:
acute toxicity: oral
Type of information:
read-across based on grouping of substances (category approach)
Adequacy of study:
key study
Justification for type of information:
Systemic mammalian toxicity will be influenced by the degree to which the substances are capable of being absorbed via the appropriate route of exposure.

At physiological pH, the substances dissociate and release boric acid and lithium ions as a result of relevant transformation pathways. It will be the boric acid component of the substances which will drive the mammalian toxicity endpoints. In order to minimise animal testing, only one substance in the category was tested, dilithium tetraborate. For all other substances in the category, read-across is proposed.

Data source

Materials and methods

Test material

Constituent 1
Chemical structure
Reference substance name:
lithium(1+) tetrahydroxyboranuide
EC Number:
818-953-3
Cas Number:
12006-96-1
Molecular formula:
LiB(OH)4
IUPAC Name:
lithium(1+) tetrahydroxyboranuide

Results and discussion

Effect levels
Key result
Sex:
female
Dose descriptor:
LD50
Effect level:
500 mg/kg bw
Based on:
test mat.

Applicant's summary and conclusion

Interpretation of results:
Category 4 based on GHS criteria
Conclusions:
At physiological pH, the substances dissociate and release boric acid and lithium ions as a result of relevant transformation pathways. It will be the boric acid component of the substances which will drive the mammalian toxicity endpoints. Read-across to the result for dilithium tetraborate is proposed for this endpoint which quotes an oral LD50 value for dilithium tetraborate in Wistar rats in the range of 300-2000 mg/kg body weight. The same result is therefore quoted for lithium tetrahydroxyborate.
Executive summary:

The oral LD50 value of dilithium tetraborate in Wistar rats was established to be within the range of 300-2000 mg/kg body weight. According to the OECD 423 test guideline, the LD50 cut-off value was considered to be 500 mg/kg body weight.

 

Based on these results, dilithium tetraborate should be classified as Category 4 based on GHS criteria. Variations in structure (trigonal vs tetrahedral) between the substances are not expected to lead to any changes as at physiological pH as all the substances dissociate to provide the same common compounds. It can be concluded that all substances in the category including lithium tetrahydroxyborate should be classified as acute toxicity, category 4.