Lithium chloride

Genetic toxicity: in vitro

Administrative data

Endpoint:

in vitro gene mutation study in bacteria

Type of information:

experimental study

Adequacy of study:

key study

Study period:

1999-11-25 to 2000-01-17

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

1999

Report date:

2000

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

OECD Guideline 471 (Bacterial Reverse Mutation Assay)

Version / remarks:

July 1997

Deviations:

no

Principles of method if other than guideline:

Not applicable

GLP compliance:

yes

Type of assay:

bacterial reverse mutation assay

Test material

Test material information

Constituent 1

Reference substance name:

Lithium hydroxide

EC Number:

215-183-4

EC Name:

Lithium hydroxide

Cas Number:

1310-65-2

Molecular formula:

HLiO

IUPAC Name:

Lithium hydroxide (Li(OH))

Test material form:

solid

Method

Target gene:

The Salmonella typhimurium histidine (his) reversion system measures his- -> his+ reversions. The Salmonella typhimurium strains are constructed to differentiate between base pair (TA 1535, TA 100) and frameshift (TA 1537, TA 98) mutations. The Escherichia coli WP2 uvrA (trp) reversion system measures trp– -> trp+ reversions. The Escherichia coli WP2 uvrA detect mutagens that cause other base-pair substitutions (AT to GC).

Species / strain

Species / strain 1

Species / strain / cell type:

S. typhimurium TA 1535, TA 1537, TA 98 and TA 100

Additional strain / cell type characteristics:

not specified

Species / strain 2

Species / strain / cell type:

E. coli WP2 uvr A

Additional strain / cell type characteristics:

not specified

Metabolic activation:

with and without

Metabolic activation system:

S9 Mix

Test concentrations with justification for top dose:

Lithium Hydroxide was tested in concentrations of 3, 10, 33, 100, 333, 1000, 3330 and 5000 µg/plate with and without S9 mix.

Vehicle / solvent:

None

Controls

Controls 1

Untreated negative controls:

yes

Negative solvent / vehicle controls:

yes

True negative controls:

yes

Positive controls:

yes

Positive control substance:

sodium azide

Remarks:

TA 1535 without S9 Migrated to IUCLID6: NaN3

Controls 2

Untreated negative controls:

yes

Negative solvent / vehicle controls:

yes

True negative controls:

yes

Positive controls:

yes

Positive control substance:

9-aminoacridine

Remarks:

TA 1537 without S9 Migrated to IUCLID6: 9AA

Controls 3

Untreated negative controls:

yes

Negative solvent / vehicle controls:

yes

True negative controls:

yes

Positive controls:

yes

Positive control substance:

other: daunomycine (DA)

Remarks:

TA 98 without S9

Controls 4

Untreated negative controls:

yes

Negative solvent / vehicle controls:

yes

True negative controls:

yes

Positive controls:

yes

Positive control substance:

methylmethanesulfonate

Remarks:

TA 100 without S9 Migrated to IUCLID6: MMS

Controls 5

Untreated negative controls:

yes

Negative solvent / vehicle controls:

yes

True negative controls:

yes

Positive controls:

yes

Positive control substance:

4-nitroquinoline-N-oxide

Remarks:

WP2uvrA without S9

Controls 6

Untreated negative controls:

yes

Negative solvent / vehicle controls:

yes

True negative controls:

yes

Positive controls:

yes

Positive control substance:

other: 2-aminoanthracene (2-AA)

Remarks:

TA 1537, TA 1535, TA 98, TA 100, E. coli WP2uvrA with S9

Details on test system and experimental conditions:

The test substance was dissolved in Milli-Q-water. The test substance was ground and the stock solution was filter (0.22 µm)-sterilized. Test substance concentrations were prepared directly prior to use.

Range finding study:
Lithium Hydroxide was tested in the tester strains TA 100 and WP2uvrA with concentrations of 3, 10, 33, 100, 333, 1000, 3330 and 5000 µg/plate in the absence and in the presence of S9 mix.

Mutation assay:
Based on the results of the dose range finding study, Lithium Hydroxide was tested up to concentrations of 5000 µg/plate in the absence and in the presence of S9-mix in two mutation experiments. The first mutation experiment was performed with the strains TA 1535, TA 1537 and TA 98 and the second mutation experiment was performed with the strains TA 1535, TA 1537, TA 98 TA 100 and WP2uvrA.

Evaluation criteria:

A test substance is considered negative (not mutagenic) in the test if:
a) The total number of revertants in any tester strain at any concentration is not greater than two times the solvent control value, with or without metabolic activation.
b) The negative response should be reproducible in at least one independently repeated experiment.

A test substance is considered positive (mutagenic) in the test if:
a) It induces a number of revertant colonies, dose related, greater than two-times the number of revertants induced by the solvent control in any tester strains, either with or without metabolic activation.
However, any mean plate count of less than 20 is considered to be not significant.
b) The positive response should be reproducible in at least one independently repeated experiment.

Statistics:

Not indicated

Results and discussion

Test results

Test results 1

Key result

Species / strain:

S. typhimurium TA 100

Genotoxicity:

negative

Cytotoxicity / choice of top concentrations:

no cytotoxicity

Vehicle controls validity:

valid

Untreated negative controls validity:

valid

Positive controls validity:

valid

Test results 2

Key result

Species / strain:

S. typhimurium TA 98

Metabolic activation:

with and without

Genotoxicity:

negative

Cytotoxicity / choice of top concentrations:

no cytotoxicity

Vehicle controls validity:

valid

Untreated negative controls validity:

valid

Positive controls validity:

valid

Test results 3

Key result

Species / strain:

S. typhimurium TA 1537

Metabolic activation:

with and without

Genotoxicity:

negative

Cytotoxicity / choice of top concentrations:

no cytotoxicity

Vehicle controls validity:

valid

Untreated negative controls validity:

valid

Positive controls validity:

valid

Test results 4

Key result

Species / strain:

S. typhimurium TA 1535

Metabolic activation:

with and without

Genotoxicity:

negative

Cytotoxicity / choice of top concentrations:

no cytotoxicity

Vehicle controls validity:

valid

Untreated negative controls validity:

valid

Positive controls validity:

valid

Test results 5

Key result

Species / strain:

E. coli WP2 uvr A

Metabolic activation:

with and without

Genotoxicity:

negative

Cytotoxicity / choice of top concentrations:

no cytotoxicity

Vehicle controls validity:

valid

Untreated negative controls validity:

valid

Positive controls validity:

valid

Additional information on results:

GENOTOXICITY:
Please refer to tables 1 and 2, which are presented under Sect. "Remarks on results including tables and figures"
- without metabolic activation: No increase in the number of revertants/plate observed
- with metabolic activation: No increase in the number of revertants/plate observed

CYTOTOXICITY:
No reduction of the bacterial background lawn was observed in all dose levels tested.

Remarks on result:

other: all strains/cell types tested

Remarks:

Migrated from field 'Test system'.

Any other information on results incl. tables

Experiment 1

Mutagenic response of Lithium Hydroxide in the Salmonella typhimurium reverse mutation assay and the Escherichia coli reverse mutation assay:

Dose (μg/plate)	Mean number of revertant colonies/3 replicate plates (±S.D.) with different strains of Salmonella typhimurium and one Escherichia coli strain
	TA 1535	TA 1537	TA 98	TA 100	WP2uvrA
Without S9-mix
positive control	219±33	435±100	371±39	466±22	172±32
solvent control	12±6	7±3	16±3	65±2	9±2
3				77±13	12±3
10				72±7	11±3
33				79±8	8±2
100	12±1	7±5	18±3	74±8	12±3
333	15±1	7±1	16±4	65±7	7±3
1000	14±3	4±2	19±3	80±8	9±2
3330	11±3	8±3	12±4	77±13	5±2
5000	12±1	6±2	12±5	77±11	4±1
With S9-mix [1]
positive control	296±23	703±22	1346±230	1199±176	237±37
solvent control	14±6	6±2	26±3	90±10	11±3
3				96±4	12±3
10				99±5	12±4
33				95±9	9±3
100	11±3	6±3	31±4	78±11	12±2
333	15±1	4±1	27±9	101±5	10±1
1000	18±7	9±1	26±6	83±12	11±3
3330	15±6	5±1	25±3	86±14	7±4
5000	14±2	4±1	22±3	65±1	4±1

Solvent control: 0.1 ml Milli-Q water

[1]The S9-mix contained 5% (v/v) S9 fraction

Experiment 2

Mutagenic response of Lithium Hydroxide in the Salmonella typhimurium reverse mutation assay and in the escherichia coli reverse mutation assay:

Dose (μg/plate)	Mean number of revertant colonies/3 replicate plates (±S.D.) with different strains of Salmonella typhimurium and one Escherichia coli strain
	TA 1535	TA 1537	TA 98	TA 100	WP2uvrA
Without S9-mix
positive control	195±2	287±105	642±125	608±24	696±16
solvent control	10±1	4±2	15±4	69±10	8±1
100	12±4	4±2	13±2	79±13	10±1
333	8±3	4±3	16±7	68±10	8±3
1000	12±5	5±2	15±2	70±7	11±2
3330	11±4	4±2	10±4	60±11	6±1
5000	7±1	5±2	11±3	64±8	7±3
With S9-mix [1]
positive control	203±14	367±45	551±25	709±131	70±8
solvent control	9±1	3±2	23±3	67±6	11±5
100	10±4	3±1	23±3	84±14	12±3
333	8±2	3±3	25±4	70±8	12±2
1000	9±4	6±3	22±6	68±11	7±2
3330	11±5	3±2	14±4	49±6	7±2
5000	5±3	3±2	13±2	54±8	3±1

 

Solvent control: 0.1 ml Milli-Q water

[1]The S9-mix contained 5% (v/v) S9 fraction

Applicant's summary and conclusion

Conclusions:

Interpretation of results (migrated information):
negative with and without metabolic activation

Based on the results of this study it is concluded that Lithium Hydroxide is not mutagenic in the Salmonella typhimurium reverse mutation assay and in the Escherichia coli reverse mutation assay.

Executive summary:

A Bacteria Reverse Mutation test with Lithium chloride is not available. Consequently, read across was applied using study results obtained from Lithium hydroxide.

Lithium Hydroxide was tested in the Salmonella typhimurium reverse mutation assay according to OECD Guideline 471. The test was performed with four histidine-requiring strains of Salmonella typhimurium (TA 1535, TA 1537, TA 100 and TA 98) and in the Escherichia coli reverse mutation assay with a tryptophane-requiring strain of Escherichia coli WP2uvrA in two independent experiments. Lithium Hydroxide was tested up to concentrations of 5000 µg/plate in the absence and presence of S9 -mix. Lithium Hydroxide did not precipitate on the plates at this dose level. The bacterial background lawn was not reduced at all concentrations tested. Reduction in the number of revertants was observed in the tester strain TA 1535, TA 98, TA 100 and WP2uvrA. Lithium Hydroxide did not induce a dose-related, two-fold, increase in the number of revertant (His+) colonies in each of the four tester strains (TA 1535, TA 1537, TA 98 and TA 100) and in the number of revertant (Trp+) colonies in the tester strain WP2uvrA both in the absence and presence of S9 -metabolic activation. These results were confirmed in an independently repeated experiment. Based on the results of this study it is concluded that Lithium Hydroxide is not mutagenic in the Salmonella typhimurium reverse mutation assay and in the Escherichia coli reverse mutation assay.