2,4,6-trichloroaniline

Endpoint summary

Key value for chemical safety assessment

Genetic toxicity in vitro

Description of key information

Gene mutation in vitro:

Ames test:

Gene mutation toxicity study was performed to determine the mutagenic nature of the test chemical. The study was performed using Salmonella typhimurium strains TA98, TA97, TA100 and TA1535 in the presence and absence of S9 metabolic activation system. The chemical was dissolved in DMSO as solvent and used at dose levels 0, 1.0, 3.3, 10, 33, 67, 100, 200, 333, 667 µg/plate by the preincubation method. The doses were selected on the basis of preliminary dose range finding study and concurrent solvent and positive controls were included in the study. The test chemical did not induce gene mutation in Salmonella typhimurium TA98, TA100, TA1538 in the presence and absence of S9 metabolic activation system and hence is not likely to classify as a gene mutant in vitro.

Chromosome aberration study:

In vitro mammalian chromosome aberration test for the test chemical. The study was performed usingChinese hamster lung (CHL) cells in the presence and absence of S9 metabolic activation system. The test chemical was dissolved in DMSO and used at dose level of0.04-0.16 mg/mL (24 hrs; -S9), 0.04-0.24 mg/mL (48 hrs; -S9), 0.025-0.1 mg/mL (6 hrs, -S9) and 0.025-0.2 mg/mL (6 hrs, +S9). 6 hrs treatment was followed by 18 hrs recovery period. The test chemical did not induce chromosomal aberration in the Chinese hamster lung (CHL) cells and hence it is not likely to classify as a gene mutant in vitro.

Link to relevant study records

Reference

Reference 1

Endpoint:

in vitro gene mutation study in bacteria

Remarks:

Type of genotoxicity: gene mutation

Type of information:

experimental study

Adequacy of study:

key study

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

data from handbook or collection of data

Justification for type of information:

Data is from peer reviewed publication

Qualifier:

according to guideline

Guideline:

other: Similar to OECD 471

Principles of method if other than guideline:

Gene mutation toxicity study was performed to evaluate the mutagenic nature of the test chemical

GLP compliance:

not specified

Type of assay:

bacterial gene mutation assay

Target gene:

Histidine

Species / strain / cell type:

S. typhimurium, other: TA 100, TA 1535, TA97 and TA98

Remarks:

Lab 1

Details on mammalian cell type (if applicable):

Not applicable

Additional strain / cell type characteristics:

not specified

Cytokinesis block (if used):

No data

Metabolic activation:

with and without

Metabolic activation system:

S9 metabolic activation 10% and 30% hamster liver S9 and 10% and 30% rat liver S9

Test concentrations with justification for top dose:

Lab 1: 0, 1.0, 3.3, 10, 33, 67, 100, 200, 333, 667 µg/plate

Vehicle / solvent:

- Vehicle(s)/solvent(s) used: DMSO
- Justification for choice of solvent/vehicle: The test chemical was soluble in DMSO

Untreated negative controls:

not specified

Negative solvent / vehicle controls:

yes

Remarks:

DMSO

True negative controls:

not specified

Positive controls:

yes

Positive control substance:

other: sodium azide

Remarks:

For strain TA1535 and TA100

Untreated negative controls:

not specified

Negative solvent / vehicle controls:

yes

Remarks:

DMSO

True negative controls:

not specified

Positive controls:

yes

Positive control substance:

9-aminoacridine

Remarks:

For strain TA97

Untreated negative controls:

not specified

Negative solvent / vehicle controls:

yes

Remarks:

DMSO

True negative controls:

not specified

Positive controls:

yes

Positive control substance:

other: 4-nitro-o-phenylenediamine

Remarks:

For strain TA98

Untreated negative controls:

not specified

Negative solvent / vehicle controls:

yes

True negative controls:

not specified

Positive controls:

yes

Positive control substance:

other: 2-aminoanthracene.

Remarks:

For metabolic activation with all strains

Details on test system and experimental conditions:

METHOD OF APPLICATION: Preincubation

DURATION
- Preincubation period: 20 mins
- Exposure duration: 2 days
- Expression time (cells in growth medium): 2 days

Rationale for test conditions:

No data

Evaluation criteria:

The plates were observed for a dose dependent increase in the number of Histidine- independent (his+) colonies.

Evaluations were made at both the individual trial and chemical levels.

Individual trials were judged mutagenic (+), weakly mutagenic (+ W), questionable (?), or nonmutagenic (-), depending on the magnitude of the increase in his+ revertants, and the shape of the dose response. A trial was considered questionable (?) if the dose-response was judged insufficiently high to support a call of “+ W”, if only a single dose was elevated over the control, or if a weak increase was not dose-related. The distinctions between a questionable response and a nonmutagenic or weakly mutagenic response, and between a weak mutagenic response and mutagenic response are highly subjective. It was not necessary for a response to reach two-fold over background for a trial to be judged mutagenic.

A chemical was judged mutagenic (+) or weakly mutagenic (+W) if it produced a reproducible, dose-related response over the solvent control, under a single metabolic activation condition, in replicate trials. A chemical was judged questionable (?) if the results of individual trials were not reproducible, if increases in his+ revertants did not meet the criteria for a “+W” response, or if only single doses produced increases in his+ revertants in repeat trials. Chemicals were judged nonmutagenic (-) if they did not meet the criteria for a mutagenic or questionable response.

Statistics:

Mean, SEM

Species / strain:

S. typhimurium, other: TA 100, TA 1535, TA97 and TA98

Metabolic activation:

with and without

Genotoxicity:

negative

Cytotoxicity / choice of top concentrations:

not specified

Vehicle controls validity:

valid

Untreated negative controls validity:

not specified

Positive controls validity:

valid

Additional information on results:

TEST-SPECIFIC CONFOUNDING FACTORS
- Effects of pH: No data
- Effects of osmolality: No data
- Evaporation from medium: No data
- Water solubility: No data
- Precipitation: No data
- Other confounding effects: No data

RANGE-FINDING/SCREENING STUDIES: All chemicals were run initially in a toxicity assay to determine the appropriate dose range for the mutagenicity assay. The toxicity assay was performed using TA100. Toxic concentrations were defined as those that produced a decrease in the number of his+ colonies, or a clearing in the density of the background lawn, or both.

COMPARISON WITH HISTORICAL CONTROL DATA: No data

ADDITIONAL INFORMATION ON CYTOTOXICITY: No data

Remarks on result:

other: No mutagenic potential

Table: Results for the test chemical

Dose (µg/plate)	TA100
	NA		10% HLI		30% HLI		10% RLI		30% RLI
	Mean	SEM	Mean	SEM	Mean	SEM	Mean	SEM	Mean	SEM
0	147	7.5	102	3.5	150	8.3	121	4.5	176	6.6
1	107	5.2
3.3	120	7.8	101	6.1			115	1.5
10	115	3.4	110	3.2	147	13.7	108	9.6	178	4.9
33	115	1.5	115	3.5	141	9.4	110	3.2	162	7.4
67			119	6.3	148	15.4	115	3.7	166	5.0
100			63s	23.2			26s	22.9
200					129	5.9			6s	4.7
333					T				T
667
Positive control	444	19.3	279	10.1	658	122.3	1197	32.6	1262	30.1

 

Dose (µg/plate)	TA1535
	NA		10% HLI		30% HLI		10% RLI		30% RLI
	Mean	SEM	Mean	SEM	Mean	SEM	Mean	SEM	Mean	SEM
41	8.4	23	0.7	15	3.9	25	3.5	17	0.6	6.6
1	42	4.4
3.3	41	1.9	18	1.2	12	0.99	25	2.0	10	0.6
10	42	1.5	22	1.5	14	1.2	25	1.9	14	0.7
33	36	2.1	25	0.7	17	0.9	24	2.9	14	1.5
67	23s	5.0
100			17	3.3	23	2.1	17	2.1	18	0.9
200			6s	1.0			7s	3.5
333					17s	1.7			4s	2.5
667
Positive control	277	14.0	65	6.9	249	1.8	271	7.7	266	7.8

 

Dose (µg/plate)	TA97
	NA		10% HLI		30% HLI		10% RLI		30% RLI
	Mean	SEM	Mean	SEM	Mean	SEM	Mean	SEM	Mean	SEM
0	118	4.5	135	6.9	176	4.9	117	5.2	190	3.0
1	115	4.4
3.3	119	4.3	103	4.0	189	5.8	140	7.0	172	10.5
10	117	9.3	120	12.3	187	7.8	135	7.0	155	9.5
33	111	2.8	124	1.8	214	4.7	145	7.3	192	5.0
67	96s	5.5
100			153s	10.0	218	10.6	159s	5.6	199	18.4
200			91s	25.0			86s	1.0
333					146s	15.4			T
667
Positive control	387	72.7	1061	4.3	1341	17.0	1993	3.9	1232	71.6

 

Dose (µg/plate)	TA98
	NA		10% HLI		30% HLI		10% RLI		30% RLI
	Mean	SEM	Mean	SEM	Mean	SEM	Mean	SEM	Mean	SEM
0	24	2.0	39	0.3	28	4.3	37	5.5	29	3.3
1	20	1.5
3.3	25	1.7	39	4.8			35	2.6
10	25	2.6	41	3.8	33	4.1	37	4.6	32	3.5
33	19	1.9	37	3.8	28	2.9	36	0.9	27	0.6
67	14s	1.8
100			37	3.7	32	1.5	26	2.8	34	3.8
200			18s	3.2			14s	10.5	6s	4.7
333					19s	9.5			6s	2.8
667					T				T
Positive control	309	19.1	230	7.5	138	12.3	201	11.2	335	9.3

 

T: Toxic

Conclusions:

The test chemical did not induce gene mutation in Salmonella typhimurium TA98, TA100, TA1538 in the presence and absence of S9 metabolic activation system and hence is not likely to classify as a gene mutant in vitro.

Executive summary:

Gene mutation toxicity study was performed to determine the mutagenic nature of the test chemical. The study was performed using Salmonella typhimurium strains TA98, TA97, TA100 and TA1535 in the presence and absence of S9 metabolic activation system. The chemical was dissolved in DMSO as solvent and used at dose levels 0, 1.0, 3.3, 10, 33, 67, 100, 200, 333, 667 µg/plate by the preincubation method. The doses were selected on the basis of preliminary dose range finding study and concurrent solvent and positive controls were included in the study. The test chemical did not induce gene mutation in Salmonella typhimurium TA98, TA100, TA1538 in the presence and absence of S9 metabolic activation system and hence is not likely to classify as a gene mutant in vitro.

Reference 2

Endpoint:

in vitro cytogenicity / chromosome aberration study in mammalian cells

Type of information:

experimental study

Adequacy of study:

key study

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

data from handbook or collection of data

Justification for type of information:

Data is from authoritative database

Qualifier:

according to guideline

Guideline:

other: Refer below principle

Principles of method if other than guideline:

In vitro mammalian chromosome aberration test for the test chemical

GLP compliance:

not specified

Type of assay:

other: In vitro mammalian chromosome aberration test

Target gene:

No data

Species / strain / cell type:

mammalian cell line, other: CHL cells

Details on mammalian cell type (if applicable):

No data

Additional strain / cell type characteristics:

not specified

Cytokinesis block (if used):

No data

Metabolic activation:

with and without

Metabolic activation system:

Rat, Liver, S-9, Sodium Phenobarbital And 5,6-Benzoflavone

Test concentrations with justification for top dose:

Continuous treatment (24 hrs; -S9): 0.04-0.16 mg/mL
Continuous treatment (48 hrs; -S9): 0.04-0.24 mg/mL
Short term treatment (6 hrs, -S9): 0.025-0.1 mg/mL
Short term treatment (6 hrs, +S9): 0.025-0.2 mg/mL

Vehicle / solvent:

- Vehicle(s)/solvent(s) used: DMSO
- Justification for choice of solvent/vehicle: The test chemical was soluble in DMSO

Untreated negative controls:

not specified

Negative solvent / vehicle controls:

not specified

True negative controls:

not specified

Positive controls:

not specified

Positive control substance:

not specified

Details on test system and experimental conditions:

METHOD OF APPLICATION: in medium

DURATION
- Preincubation period: No data
- Exposure duration: No data
- Expression time (cells in growth medium): No data
- Selection time (if incubation with a selection agent): No data
- Fixation time (start of exposure up to fixation or harvest of cells): No data

SELECTION AGENT (mutation assays): No data
SPINDLE INHIBITOR (cytogenetic assays): No data
STAIN (for cytogenetic assays): No data

NUMBER OF REPLICATIONS: No data

NUMBER OF CELLS EVALUATED: No data

DETERMINATION OF CYTOTOXICITY
- Method: mitotic index; cloning efficiency; relative total growth; other: No data

OTHER EXAMINATIONS:
- Determination of polyploidy: No data
- Determination of endoreplication: No data
- Other: No data

OTHER: No data

Rationale for test conditions:

No data

Evaluation criteria:

The cell line was observed for chromosomal aberrations

Statistics:

No data

Species / strain:

mammalian cell line, other: CHL cells

Metabolic activation:

with and without

Genotoxicity:

negative

Cytotoxicity / choice of top concentrations:

not specified

Vehicle controls validity:

not specified

Untreated negative controls validity:

not specified

Positive controls validity:

not specified

Additional information on results:

No data

Remarks on result:

other: No mutagenic potential

Conclusions:

The test chemical did not induce chromosomal aberration in the Chinese hamster lung (CHL) cells and hence it is not likely to classify as a gene mutant in vitro.

Executive summary:

In vitro mammalian chromosome aberration test for the test chemical. The study was performed usingChinese hamster lung (CHL) cells in the presence and absence of S9 metabolic activation system. The test chemical was dissolved in DMSO and used at dose level of0.04-0.16 mg/mL (24 hrs; -S9), 0.04-0.24 mg/mL (48 hrs; -S9), 0.025-0.1 mg/mL (6 hrs, -S9) and 0.025-0.2 mg/mL (6 hrs, +S9). 6 hrs treatment was followed by 18 hrs recovery period. The test chemical did not induce chromosomal aberration in the Chinese hamster lung (CHL) cells and hence it is not likely to classify as a gene mutant in vitro.

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed (negative)

Genetic toxicity in vivo

Description of key information

Gene mutation in vivo:

Gene mutation in vivo was performed for the test chemical using Drosophila melanogaster. 72-h-old larvae of Drosophila melanogaster, trans-heterozygous for the mutations multiple wing hair (mwh, 3-0.0) and flare (fir, 3-38.8), were fed the test compound (5mM (9823 mg/L)) for 48 h. Test compound was dissolved in an aqueous solution containing 3% absolute ethanol and 1% Tween 80 and used to prepare Drosophila Instant Medium (Formula 4- 24, Carolina Biological Supply Company, Burlington, NC, U.S.A.) at dose of 5mM. In order to determine the spontaneous mutation frequency, additional larvae were simultaneously exposed to the solvent only. The larvae were treated, and the wings prepared and scored for induced spots. Statistical analysis of the data was carried out as described by Frei and Würgler (1988). The test chemical is considered to be positive for inducing somatic and recombinant mutation using Drosophila melanogaster.

Link to relevant study records

Reference

Endpoint:

in vivo mammalian germ cell study: gene mutation

Remarks:

Type of genotoxicity: gene mutation

Type of information:

experimental study

Adequacy of study:

key study

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

data from handbook or collection of data

Justification for type of information:

Data is from peer reviewed publication

Qualifier:

according to guideline

Guideline:

other: Refer below principle

Principles of method if other than guideline:

The test chemical was investigated for genotoxicity in Drosophila.

GLP compliance:

not specified

Type of assay:

somatic mutation and recombination test in Drosophila

Species:

Drosophila melanogaster

Strain:

not specified

Sex:

not specified

Details on test animals or test system and environmental conditions:

TEST ANIMALS:
- Age at study initiation: 72 hr old larvae
- Diet (e.g. ad libitum): Drosophila Instant Medium

Route of administration:

oral: feed

Vehicle:

- Vehicle(s)/solvent(s) used: absolute ethanol and Tween 80
- Concentration of test material in vehicle: 5mM (9823 mg/L)
- Amount of vehicle (if gavage or dermal): No data

Details on exposure:

Details on exposure
For oral route
PREPARATION OF DOSING SOLUTIONS: Test compound were dissolved in an aqueous solution containing 3% absolute ethanol and 1% Tween 80 and used to prepare Drosophila Instant Medium (Formula 4- 24, Carolina Biological Supply Company, Burlington, NC, U.S.A.).

Duration of treatment / exposure:

48 hrs

Frequency of treatment:

No data available

Post exposure period:

No data available

Remarks:

Doses / Concentrations:
5mM (9823 mg/L)
Basis:
nominal in diet

No. of animals per sex per dose:

No data

Control animals:

yes, concurrent vehicle

Positive control(s):

No data

Tissues and cell types examined:

Multiple wing hair and flare

Details of tissue and slide preparation:

No data

Evaluation criteria:

Induced spots on wings were examined acc. to Graf et al.

Statistics:

Statistical analysis of the data was carried out as described by Frei and Würgler (1988).

Sex:

not specified

Genotoxicity:

positive

Toxicity:

not specified

Vehicle controls validity:

not specified

Negative controls validity:

not specified

Positive controls validity:

not specified

Additional information on results:

No data

Compound and concentration	Number of wings	Spots per wing and statistical diagnoses
		Small single spots m= 2.0	Large single spots m= 5.0	Twin spots m= 5.0	Total spots m= 2.0
2,4,6-TCA 5 mM	80	0.45 +	0.08 -	0.01 i	0.54 +

Note: += positive; -= negative; i= inconclusive

Conclusions:

The test chemical is considered to be positive for inducing somatic and recombinant mutation using Drosophila melanogaster.

Executive summary:

Gene mutation in vivo was performed for the test chemical using Drosophila melanogaster. 72-h-old larvae of Drosophila melanogaster, trans-heterozygous for the mutations multiple wing hair (mwh, 3-0.0) and flare (fir, 3-38.8), were fed the test compound (5mM (9823 mg/L)) for 48 h. Test compound was dissolved in an aqueous solution containing 3% absolute ethanol and 1% Tween 80 and used to prepare Drosophila Instant Medium (Formula 4- 24, Carolina Biological Supply Company, Burlington, NC, U.S.A.) at dose of 5mM. In order to determine the spontaneous mutation frequency, additional larvae were simultaneously exposed to the solvent only. The larvae were treated, and the wings prepared and scored for induced spots. Statistical analysis of the data was carried out as described by Frei and Würgler (1988). The test chemical is considered to be positive for inducing somatic and recombinant mutation using Drosophila melanogaster.

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed (negative)

Additional information

Gene mutation in vitro:

Data available for the test chemical was reviewed to determine the mutagenic nature of 2,4,6 -trichloroaniline, The studies are as mentioned below:

Gene mutation toxicity study was performed to determine the mutagenic nature of the test chemical. The study was performed using Salmonella typhimurium strains TA98, TA97, TA100 and TA1535 in the presence and absence of S9 metabolic activation system. The chemical was dissolved in DMSO as solvent and used at dose levels 0, 1.0, 3.3, 10, 33, 67, 100, 200, 333, 667 µg/plate by the preincubation method. The doses were selected on the basis of preliminary dose range finding study and concurrent solvent and positive controls were included in the study. The test chemical did not induce gene mutation in Salmonella typhimurium TA98, TA100, TA1538 in the presence and absence of S9 metabolic activation system and hence is not likely to classify as a gene mutant in vitro.

In vitro mammalian chromosome aberration test for the test chemical. The study was performed usingChinese hamster lung (CHL) cells in the presence and absence of S9 metabolic activation system. The test chemical was dissolved in DMSO and used at dose level of0.04-0.16 mg/mL (24 hrs; -S9), 0.04-0.24 mg/mL (48 hrs; -S9), 0.025-0.1 mg/mL (6 hrs, -S9) and 0.025-0.2 mg/mL (6 hrs, +S9). 6 hrs treatment was followed by 18 hrs recovery period. The test chemical did not induce chromosomal aberration in the Chinese hamster lung (CHL) cells and hence it is not likely to classify as a gene mutant in vitro.

In another study, gene mutation toxicity study was performed to determine the mutagenic nature of the test chemical. The study was performed using Salmonella typhimurium strains TA98, TA100 and TA1535 in the presence and absence of S9 metabolic activation system. The chemical was dissolved in DMSO as solvent and used at dose levels 0, 1.0, 3.0, 10, 33, 66, 100, 166, 333, 666, 1000, 3333 µg/plate by the preincubation method. The doses were selected on the basis of preliminary dose range finding study and concurrent solvent and positive controls were included in the study. The test chemical did not induce gene mutation in Salmonella typhimurium TA98, TA100 (30% RLI), TA1538 in the presence and absence of S9 metabolic activation system. It however induced gene mutation in Salmonella typhimurum strain TA100 in the presence of 30% HLI. Based on the observations made, the test chemical is not likely to classify as a gene mutant in vitro.

Salmonella/microsome test was performed to determine the mutagenic nature of test chemical. The study was performed using Salmonella typhimurium strains TA98, TA1537 and TA100 in the presence and absence of S9 metabolic activation system. The test chemical was dissolved in DMSO. To 4 ml of top agar at 45°C, 0.2 ml of S. typhimurium (about 4 × 10⁸bacteria) 0.1 ml of drug in DMSO, and 1.0 ml of S9 mix were added. The resulting mixture was then dispersed rapidly with a 5-ml disposable pipette and 2 ml was plated on top of 20 ml agar in each of 2 plates. Top agar was spread by tilting the plates, allowed to harden and incubated for 40 h at 37°.The revertant count for each point was the average of duplicate plates scored on a modified Artek Model 870 Colony Counter.The test chemical did not induce gene mutation inSalmonella typhimurium strains TA98, TA1537 and TA100 in the presence and absence of S9 metabolic activation systemand hence it is not likely to classify as a gene mutant in vitro.

Suspension assay was also performed to determine the mutagenic nature of test chemical. The study was performed using Salmonella typhimurium strains TA98, TA1537 and TA100 in the presence and absence of S9 metabolic activation system. To 0.2 ml of cells, 0.02 ml of drug in DMSO, and 1.0 ml of S9 mix were added in a 13 × 100 mm tube and incubated for 30 min at 37°C. Top agar was then added and the mixture was plated for 40 h at 37°.The test chemical did not induce gene mutation inSalmonella typhimurium strains TA98, TA1537 and TA100 in the presence and absence of S9 metabolic activation system in the suspension assay and hence it is not likely to classify as a gene mutant in vitro.

In yet another study, the hepatocyte/DNA repair test which measures unscheduled DNA synthesis (UDS) was performed to determine the genotoxicity of the test chemical using male ACI rat hepatocytes. The test was performed basically in accordance with the method of Williams et al. The test material was dissolved in DMSO, used at dose level of 10^-3, 10^-4, 10^-5, 10^-6M and the positive control used was N-2-fluorenylacetamide. The isolated hepatocytes were allowed to attach for 2 h on plastic coverslips in primary culture using Williams' Medium E. The cultures were then washed and exposed to the test chemical and [Me- 3H]thymidine (10 µCi/ml; 49 Ci/mmole) for 20 h. At the end of incubation, the cultures were washed, and the coverslips were mounted on glass slides. The slides were dipped in Sakura NR-M2 photographic emulsion and exposed for 14 days. Autoradiographic grains were counted on a television screen (Olympus, type S) with a microscopic attachment. The data were expressed as the average net counts/nucleus for 3 coverslips + the standard deviation (50 cells/coverslip). The test chemical was considered positive when the mean net nuclear grain count was more than 5 grains above background and statistically greater than that of controls. The test chemical did not induce unscheduled DNA synthesis in the rat hepatocyte/DNA repair test using male ACI rat hepatocytes and hence it is not likely to classify as a gene mutant in vitro.

Gene mutation in vivo:

Gene mutation in vivo was performed for the test chemical using Drosophila melanogaster. 72-h-old larvae of Drosophila melanogaster, trans-heterozygous for the mutations multiple wing hair (mwh, 3-0.0) and flare (fir, 3-38.8), were fed the test compound (5mM (9823 mg/L)) for 48 h. Test compound was dissolved in an aqueous solution containing 3% absolute ethanol and 1% Tween 80 and used to prepare Drosophila Instant Medium (Formula 4- 24, Carolina Biological Supply Company, Burlington, NC, U.S.A.) at dose of 5mM. In order to determine the spontaneous mutation frequency, additional larvae were simultaneously exposed to the solvent only. The larvae were treated, and the wings prepared and scored for induced spots. Statistical analysis of the data was carried out as described by Frei and Würgler (1988). The test chemical is considered to be positive for inducing somatic and recombinant mutation using Drosophila melanogaster.

In vivo mammalian chromosome aberration study was performed to determine the mutagenic nature of the test chemical. The study was performed using rats. The test chemical was dissolved in DMSO and used at dose level of 0, 0.4, 4 or 40 mg/Kg/day. Rats treated orally with 2,4,6-trichloroaniline at 40 mg/kg-day (but not 0.4 or 4 mg/kg-day) for 6 months showed a small but statistically significant increase (p < 0.05) in the number of bone marrow cells containing chromosomal aberrations when compared with controls (1.6% vs. 0.4%, respectively). Based on the observations made, the given test material is positive for inducing chromosome aberrations in the bone marrow cells of rat.

However, the studies mentoined above does not give a complete description to prove the mutagenic nature of the test chemical in vivo.

Based on the observations made, the test chemical does not exibit gene mutation in vitro and in vivo. Hence it is not likely to classify as a gene mutant in vitro and in vivo as per the criteria mentioned in CLP regulation.

Justification for classification or non-classification

Based on the observations made, the test chemical 2,4,6 -trichloroaniline (CAS no 634 -93 -5) does not exibit gene mutation in vitro and in vivo. Hence it is not likely to classify as a gene mutant in vitro and in vivo as per the criteria mentioned in CLP regulation.