Dilanthanum tricarbonate

Genetic toxicity: in vitro

Administrative data

Endpoint:

in vitro gene mutation study in bacteria

Remarks:

Type of genotoxicity: gene mutation

Type of information:

experimental study

Adequacy of study:

key study

Study period:

02 Nov- 30 Nov 2005

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: GLP-Guideline study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2006

Report date:

2006

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

OECD Guideline 471 (Bacterial Reverse Mutation Assay)

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Remarks:

Hess. Ministerium für Umwelt, ländlichen Raum und Verbraucherschutz, Mainzer Straße 80, 65189 Wiesbaden, Germany

Type of assay:

bacterial reverse mutation assay

Test material

Test material information

Constituent 1

Reference substance name:

Dilanthanum tricarbonate

EC Number:

209-599-5

EC Name:

Dilanthanum tricarbonate

Cas Number:

587-26-8

Molecular formula:

La2(CO3)3

IUPAC Name:

dilanthanum tricarbonate

Method

Target gene:

His operon

Species / strain

Species / strain / cell type:

S. typhimurium, other: TA 1535, TA 1537, TA 98, TA 100, TA 102

Metabolic activation:

with and without

Metabolic activation system:

Induced rat liver S9 is used as metabolic activation system. S9 is prepared from 8-12 weeks old male Wistar Hanlbm rats induced by applications of 80 mg/kg bw Phenobarbital (i.p.) and beta-Naphthoflavone p.o. each on three consecutive days.

Test concentrations with justification for top dose:

Pre-experiment / Experiment I: with and without S9: 3, 10, 33, 100, 333, 1000, 2500 and 5000 µg/plate
Experiment II: with and without S9: 33, 100, 333, 1000, 2500 and 5000 µg/plate

Vehicle / solvent:

- Vehicle(s)/solvent(s) used: DMSO (test substance and positive controls 4-nitro-o-phenylene-diamine and 2-aminoanthracene) and deionised water (positive controls sodium azide and methylmethanesulfonate)
- Justification for choice of solvent/vehicle: DMSO was chosen for the test substancebecause of its solubility properties and its relative non-toxicity to bacteria

Controls

Untreated negative controls:

yes

Negative solvent / vehicle controls:

yes

True negative controls:

no

Positive controls:

yes

Positive control substance:

other: -S9: TA1535 and TA100: 10 µg/plate sodium azide; TA1537+TA98: 4-nitro-o-phenylene-diamine (50µg/plate in TA1537 and 10 µg/plate in TA98); TA102: methylmethanesulfonate (4µL/plate); +S9: all strains 2-aminoanthracene (2.5 µg/plate; 10 µg/plate in TA102)

Details on test system and experimental conditions:

METHOD OF APPLICATION: plate incorporation test (experiment I) and preincubation assay (experiment II)

DURATION
- Preincubation period: none for the experiment I (direct plate incorporation)
- Preincubation period: 60 minutes for the experiment II
- Incubation time: 48 hours


NUMBER OF REPLICATIONS: 2 (for each strain and dose level including the untreated, vehicle and positive controls three plates were used)

Evaluation criteria:

A test item is considered as a mutagen if a biologically relevant increase in the number of revertants exceeding the threshold of twice (strains TA 98, TA 100, and TA 102) or thrice (strains TA 1535 and TA 1537) the colony count of the corresponding solvent control is observed.
A dose dependent increase is considered biologically relevant if the threshold is exceeded at more than one concentration.
An increase exceeding the threshold at only one concentration is judged as biologically relevant if reproduced in an independent second experiment.
A dose dependent increase in the number of revertant colonies below the threshold is regarded as an indication of a mutagenic potential if reproduced in an independent second experiment. However, whenever the colony counts remain within the historical range of negative and solvent controls such an increase is not considered biologically relevant.

Results and discussion

Test results

Species / strain:

S. typhimurium, other: TA 1535, TA 1537, TA 98, TA 100, TA 102

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

Remarks on result:

other: all strains/cell types tested

Remarks:

Migrated from field 'Test system'.

Any other information on results incl. tables

Table 1a: Number of revertants per plate in pre-experiment / experiment I (mean of three plates)

	TA 1535				TA 1537				TA 98
Concentration [µg/plate]	- S9	+ S9	Precipitate (yes/no)	Cytotox (yes/no)	- S9	+ S9	Precipitate(yes/no)	Cytotox (yes/no)	- S9	+ S9	Precipitate(yes/no)	Cytotox (yes/no)
DMSO	19	27	no	no	11	16	no	no	21	30	no	no
Untreated	15	26	no	no	9	16	no	no	29	37	no	no
3	26	26	no	no	10	15	no	no	29	30	no	no
10	24	23	no	no	13	16	no	no	24	31	no	no
33	23	25	no	no	11	14	no	no	24	32	no	no
100	21	24	no	no	10	15	no	no	26	30	no	no
333	18	26	Yes (+S9)	no	11	22	Yes (+S9)	no	25	37	Yes (+S9)	no
1000	17	27	yes	no	11	17	yes	no	27	27	yes	no
2500	18	31	yes	no	12	16	yes	no	21	25	yes	no
5000	19	19	yes	no	6	9	yes	no	22	26	yes	no
NaN3	1361
4-NOPD					73				352
MMS
2-AA		220				244				1462

 

Table 1b: Number of revertants per plate in pre-experiment / experiment I (mean of three plates)

	TA 100				TA 102
Concentration [µg/plate]	- S9	+ S9	Precipit.ate (yes/no)	Cytotox (yes/no)	- S9	+ S9	Precipitate(yes/no)	Cytotox (yes/no)
DMSO	128	140	no	no	488	540	no	no
Untreated	140	170	no	no	474	590	no	no
3	141	138	no	no	478	608	no	no
10	121	140	no	no	471	496	no	no
33	135	150	no	no	418	537	no	no
100	125	140	no	no	433	504	no	no
333	136	146	Yes (+S9)	no	431	496	Yes (+S9)	no
1000	111	135	yes	no	467	457	yes	no
2500	122	144	yes	no	476	534	yes	no
5000	118	117	yes	no	336	460	yes	no
NaN3	2161
4-NOPD
MMS					4759
2-AA		1866				2042

NaN3: sodium azide; 4-NOPD: 4 -nitro-o-phenylene-diamine; MMS: methylmethanesulfonate; 2-AA: 2-aminoanthracene

Table 2a: Number of revertants per plate in experiment II (mean of three plates)

	TA 1535				TA 1537				TA 98
Concentration [µg/plate]	- S9	+ S9	Precipitate (yes/no)	Cytotox (yes/no)	- S9	+ S9	Precipitate(yes/no)	Cytotox (yes/no)	- S9	+ S9	Precipitate(yes/no)	Cytotox (yes/no)
DMSO	22	24	no	no	10	19	no	no	32	40	no	no
Untreated	26	21	no	no	13	25	no	no	25	38	no	no
33	24	25	no	no	7	19	no	no	25	38	no	no
100	20	27	no	no	11	18	no	no	32	36	no	no
333	21	29	no	no	10	18	no	no	19	35	no	no
1000	21	26	no	no	12	18	no	no	24	38	no	no
2500	21	28	no	no	11	15	no	no	27	38	no	no
5000	22	32	yes	no	9	15	yes	no	27	37	yes	no
NaN3	1274
4-NOPD					125				467
MMS
2-AA		262				129				1352

 

Table 2b: Number of revertants per plate in experiment II (mean of three plates)

	TA 100				TA 102
Concentration [µg/plate]	- S9	+ S9	Precipitate  (yes/no)	Cytotox (yes/no)	- S9	+ S9	Precipitate(yes/no)	Cytotox (yes/no)
DMSO	126	152	no	no	341	343	no	no
Untreated	176	136	no	no	372	390	no	no
33	126	109	no	no	339	367	no	no
100	113	128	no	no	344	429	no	no
333	128	133	no	no	358	457	no	no
1000	117	108	no	no	298	340	no	no
2500	111	132	no	no	321	419	no	no
5000	116	126	yes	no	324	417	yes	no
NaN3	1679
4-NOPD					1984
MMS
2-AA		1688				2112

NaN3: sodium azide; 4-NOPD: 4 -nitro-o-phenylene-diamine; MMS: methylmethanesulfonate; 2-AA: 2-aminoanthracene

The results of the second experiment are comparable to the first. No toxic effects occured in the test groups with and without metabolic activation.

Precipitation of the test solution in agar was observed from 1000 µg/plate without metabolic activation and from 333 µg/plate with metabolic activation in experiment I, and at 5000 µg/plate with and without S9 mix in experiment II. Due to precipitation of the test item the colonies were partly counted manually.

No substantial increase in revertant colony numbers in any of the five tester strains was observed following treatment with Lanthanum carbonate at any concentration level, neither in the presence nor absence of metabolic activation. In conclusion, it can be stated that during the described mutagenicity test and under the experimental conditions reported, the test item did not induce gene mutations by base pair changes or frameshifts in the genome of the strains used. Therefore, Lanthanum carbonate is considered to be non-mutagenic in this Salmonella typhimurium reverse mutation assay.

Applicant's summary and conclusion

Conclusions:

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