Lithium 2-methylpropan-2-olate

Skin irritation / corrosion

Administrative data

Endpoint:

skin corrosion: in vitro / ex vivo

Type of information:

experimental study

Adequacy of study:

key study

Study period:

1999-08-02 to 1999-08-09

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

test procedure in accordance with generally accepted scientific standards and described in sufficient detail

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2000

Report date:

2000

Materials and methods

Test guideline

Qualifier:

no guideline available

Principles of method if other than guideline:

The Corrositex assay is used as a standardized and quantitative in vitro corrosivity test. The test is based on the time that is required for the test sample to pass through a biobarrier membrane and produce a change in the Chemical Detection System (CDS). The Packing Group is determined by the time interval required to break through the biobarrier matrix.

GLP compliance:

yes

Test material

Test material information

Constituent 1

Reference substance name:

Lithium 2-methylpropan-2-olate

EC Number:

217-611-5

EC Name:

Lithium 2-methylpropan-2-olate

Cas Number:

1907-33-1

Molecular formula:

C4H10O.Li

IUPAC Name:

lithium 2-methylpropan-2-olate

Test material form:

solid

In vitro test system

Test system:

artificial membrane barrier model

Results and discussion

In vitro

Results

Irritation / corrosion parameter:

other: Mean breakthrough time

Vehicle controls validity:

not applicable

Negative controls validity:

not applicable

Positive controls validity:

valid

Remarks on result:

other: Mean breakthrough time of 17 minutes was determined.

Any other information on results incl. tables

The results of the Categorization Screen indicated that the test article, Lithium t-butoxide in tetrahydrofuran (621 -01a), fell into category 1. Therefore it was evaluated using the timetable in table 1.

The test article was examined in a single trial (four replicates) to determine the packing group and the mean breakthrough time. Table 3 summarizes the results of the definitive Corrositex assay for the test article and the positive control. The results of the positive control, NaOH (EM Science, lot# 34277449, > 97% purity), fell within two standard deviations of the historical mean, thereby meeting the acceptance criteria.

Table 3: Results of the definitive Corrositex assay

Test article	Breakthrough Time (min:sec)						pH*
	Vial 1	Vial 2	Vial 3	Vial 4	Mean	Packing Group
Lithium t-butoxide	16:40	17:45	16:45	16:50	17:00	II	14
NaOH	11:22	NA	NA	NA	11:22	NA	NA

* 100 µL : 1 mL solution in deionized water

NA: Not Applicable

Applicant's summary and conclusion

Interpretation of results:

Category 1B (corrosive) based on GHS criteria

Conclusions:

The test substance was corrosive in the corrositex assay.

Executive summary:

The purpose of this Corrositex Assay was to evaluate the potential corrosivity of the test substance, as measured by its penetration through a calibrated biobarrier into a chemical detection system (CDS). The test article was tested in one definitive assay (four replicates) to measure the mean break through time. Based on the determined break through time of 17 minutes, the test substance is considered to be corrosive.