1,2,3-trichlorobenzene

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

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: Comparable to guideline study with acceptable restrictions

Data source

Reference

Reference Type:

publication

Title:

Salmonella Mutagenicity Test results for 250 Chemicals

Author:

Haworth S, Lawlor T, Mortelmans K, Speck W, and Zeiger E

Year:

1983

Bibliographic source:

Environmental Mutagenesis Supplement 1:3-142

Materials and methods

Test guideline

Qualifier:

equivalent or similar to guideline

Guideline:

OECD Guideline 471 (Bacterial Reverse Mutation Assay)

Deviations:

yes

Remarks:

Only 4 strain tested instead of 5. Positive control: 2-aminoantracene was only indicator of efficiency of S9-mix. Individual plate reading not reported.

GLP compliance:

not specified

Type of assay:

bacterial reverse mutation assay

Test material

Test material information

Constituent 1

Reference substance name:

1,2,4-trichlorobenzene

EC Number:

204-428-0

EC Name:

1,2,4-trichlorobenzene

Cas Number:

120-82-1

Molecular formula:

C6H3Cl3

IUPAC Name:

1,2,4-trichlorobenzene

Details on test material:

- Name of test material (as cited in study report): 1,2,3-Trichlorobenzene
- Analytical purity: 97%
- Lot/batch No.: HC 060787
-Source: Radian Corporation, Austin, TX, USA

Method

Target gene:

his

Species / strain

Species / strain / cell type:

other: Salmonella typhimurium TA 98, TA 100, TA 1535, TA 1537

Additional strain / cell type characteristics:

not specified

Metabolic activation:

with and without

Metabolic activation system:

microsomal enzyme reaction mix (S9-mix)

Test concentrations with justification for top dose:

0.0, 3.3, 10.0, 33.3, 100.0, 333.3 ug/plate

Vehicle / solvent:

- Vehicle/solvent used: DMSO

Controls

Untreated negative controls:

no

Negative solvent / vehicle controls:

yes

True negative controls:

no

Positive controls:

yes

Positive control substance:

other: 2-aminoanthracene (2-AA): in all strains in presence of rat and hamster S-9. 4-Nitro-o-phenylenediamine (NOPD): on TA98, without S-9. sodium azide (SA) : on TA100 and TA 1535, without S-9. 9-aminoacridine (9-AAD) was tested on 1537, without S-9.

Remarks:

The actual concentration for each positive control chemical used for each strain and activation condition was selected by the individual laboratory based on dose-response curves generated at the beginning of the testing program (see table 1)

Details on test system and experimental conditions:

METHOD OF APPLICATION: preincubation

DURATION
- Preincubation period: 20 min
- Exposure duration: 48h
- Selection time (if incubation with a selection agent): 48h
- Concentration of S9 mix: 10% for both Hamster S9 mix and Rat S9 mix

SELECTION AGENT (mutation assays): L- histidine

NUMBER OF REPLICATIONS: 2 trial per strain and 3 dishes per dose




DETERMINATION OF CYTOTOXICITY
- Method: other: viability on complete medium and reduced numbers of revertant colonies per plate and/or thinning or absence of the bacterial lawn

Evaluation criteria:

A positive response was indicated by a reproducible, dose-related increase, whether it be twofold over background or not.
An equivocal response was defined as an increase in revertants which was not dose-related, not reproducible, or was of insufficient magnitude to support a determination of mutagenicity. A negative response was obtained when no increase in revertant colonies is observed following chemical treatment.

Results and discussion

Test results

Species / strain:

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

Metabolic activation:

with and without

Genotoxicity:

negative

Cytotoxicity / choice of top concentrations:

cytotoxicity

Vehicle controls validity:

valid

Untreated negative controls validity:

not examined

Positive controls validity:

valid

Additional information on results:

RANGE-FINDING/SCREENING STUDIES: to select the dose range for the mutagenesis assay, the test chemicals were checked for toxicity to TA 100 up to a concentration of 10 mg/plate or the limit of solubility, both in the presence and absence of S-9 mix. If toxicity was not apparent in the preliminary toxicity determination, the highest dose tested was 10 mg/plate; otherwise the upper limit of solubility was used. If toxicity was observed, the doses of test chemical were chosen so that the high dose exhibited some degree of toxicity. Occasionally, in the earlier tests, the high dose was greater than 10 mf/plate.

Remarks on result:

other: all strains/cell types tested

Remarks:

Migrated from field 'Test system'. Remarks: Salmonella typhimurium TA 98, TA 100, TA 1535, TA 1537

Any other information on results incl. tables

TA 100

TA 1535

TA 1537

TA 98

Dose

NA

RLI

HLI

NA

RLI

HLI

NA

RLI

HLI

NA

RLI

HLI

0.0

124±9.9

138±7.0

131±7.3

25±6.0

12±2.9

14±0.9

11±2.7

20±0.3

26±3.5

25±2.4

22±5.0

35±3.4

3.3

122±13.2

122±9.7

114±4.1

17±1.7

10±2.2

16±2.0

8±2.1

15±3.2

18±3.0

20±3.0

26±2.2

32±1.0

10.0

134±14.0

131±7.5

122±7.2

20±4.6

14±0.3

13±0.3

12±1.3

14±3.5

22±3.0

16±4.8

24±1.7

31±3.2

33.3

91±3.8

131±11.6

135±10.6

17±2.3

14±2.9

16±1.5

6±1.3

13±3.8

18±1.5

20±0.7

23±3.7

32±5.1

100.0

11± 6.9s

91±6.4

124±10.2

0±0.0s

8±1.5

14±3.8

0±0.0s

11±1.8

21±3.3

10±2.9s

27±0.6

31±2.0

333.3

t

t

80±2.8s

t

4±2.2s

6±0.7s

t

0±0.0s

6±1.0s

t

6±3.2s

18±6.2s

POS

550±8.1

596±29.5

556±9.5

438±5.3

334±51.3

367±6.2

163±24.0

287±3.6

467±13.0

474±16.3

388±25.1

934±19.9

Table 1 Mutagenic responses of Salmonella strains TA100, TA 1535, TA 1537, and TA 98 (mean±SEM) to 1,2,3-trochlorobenzene.

 Abbreviations:NA, not activated; RLI, rat liver S-9, Aroclor1254 induced; HLI, hamster liver S-9, Aroclor1254 induced, t=complete clearing background, s=slight clearing of background lawn

Applicant's summary and conclusion

Conclusions:

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

Executive summary:

HaworthS, 1983

Ames test was performed with theSalmonella typhimurium strains TA1535, TA1537, TA98 and TA100 at 0, 3.3, 10, 33.3, 100, and 333.3µg 1,2,3-TCB/plate with and without S-9 from Aroclor 1254 induced rat and hamster livers using the preincubation procedure. Test doses were chosen following checks for toxicity: in the absence of toxicity a maximum of 10 mg/plate was used. 1,2,3-trichlorobenzene resulted to be not mutagenic.

The test was conducted according to OECD guideline 471 with deviations (Only 4 strains tested instead of 5. Positive control: 2-aminoantracene was only indicator of efficiency of S9-mix.Individual plate reading not reported).