3,4-dichlorophenyl isocyanate

Endpoint summary

Key value for chemical safety assessment

Genetic toxicity in vitro

Description of key information

- Bacterial reverse mutation test (Ames): not mutagenic to S.thyphimurium TA 98, TA 100, TA 1535, TA 1537, TA 1538 and E. coli WP2 (eq. OECD 471, 2 non-GLP studies, key, rel.2)

- In vitro mammalian chromosome aberration test: not clastogenic to V79 cells (eq. OECD 473, non-GLP, key, rel.2).

Link to relevant study records

Reference

Reference 1

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:

other: well documented and scientifically acceptable

Qualifier:

according to guideline

Guideline:

OECD Guideline 473 (In Vitro Mammalian Chromosome Aberration Test)

GLP compliance:

yes

Type of assay:

in vitro mammalian chromosome aberration test

Target gene:

no data

Species / strain / cell type:

Chinese hamster lung fibroblasts (V79)

Additional strain / cell type characteristics:

not specified

Metabolic activation:

with and without

Metabolic activation system:

S9-mix

Test concentrations with justification for top dose:

2, 10, 20 µg/ml in the absence of metabolic activation
5, 25, 50 µg/ml in the presence of S9-mix

Vehicle / solvent:

no data

Key result

Species / strain:

Chinese hamster lung fibroblasts (V79)

Metabolic activation:

with and without

Genotoxicity:

negative

Cytotoxicity / choice of top concentrations:

cytotoxicity

Remarks:

25 µg/ml without metanolic activation, 75 µg/ml with metabolic activation

Vehicle controls validity:

valid

Untreated negative controls validity:

valid

True negative controls validity:

not specified

Positive controls validity:

valid

3,4 -dichlorophenyl isocyanate does not induce chromosome mutations (=aberrations) in V79 chinese hamster cells, neither in the presence nor in the absence of a metabolic activation system, under the experimental conditions described

Executive summary:

method: cytogenetic assay in vitro with V79 chinese hamster cells (according OECD 473)

result: negative

Reference 2

Endpoint:

in vitro gene mutation study in bacteria

Type of information:

experimental study

Adequacy of study:

key study

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: well documented and scientifically acceptable

Qualifier:

equivalent or similar to guideline

Guideline:

OECD Guideline 471 (Bacterial Reverse Mutation Assay)

GLP compliance:

yes

Type of assay:

bacterial reverse mutation assay

Species / strain / cell type:

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

Species / strain / cell type:

S. typhimurium TA 1538

Metabolic activation:

with and without

Metabolic activation system:

S-9 mix

Test concentrations with justification for top dose:

0.0032 up to 4 µg/plate

Vehicle / solvent:

no data

Species / strain:

E. coli WP2 uvr A

Remarks:

Please refer to second key study including the description of the E.coly study

Metabolic activation:

with and without

Genotoxicity:

negative

Cytotoxicity / choice of top concentrations:

not specified

Vehicle controls validity:

valid

Untreated negative controls validity:

valid

Positive controls validity:

valid

Key result

Species / strain:

S. typhimurium TA 98

Metabolic activation:

with and without

Genotoxicity:

negative

Cytotoxicity / choice of top concentrations:

not specified

Vehicle controls validity:

valid

Untreated negative controls validity:

valid

True negative controls validity:

not examined

Positive controls validity:

valid

Key result

Species / strain:

S. typhimurium TA 100

Metabolic activation:

with and without

Genotoxicity:

negative

Cytotoxicity / choice of top concentrations:

not specified

Vehicle controls validity:

valid

Untreated negative controls validity:

valid

True negative controls validity:

not specified

Positive controls validity:

valid

Key result

Species / strain:

S. typhimurium TA 1535

Metabolic activation:

with and without

Genotoxicity:

negative

Cytotoxicity / choice of top concentrations:

not specified

Vehicle controls validity:

valid

Untreated negative controls validity:

valid

True negative controls validity:

not examined

Positive controls validity:

valid

Key result

Species / strain:

S. typhimurium TA 1537

Metabolic activation:

with and without

Genotoxicity:

negative

Cytotoxicity / choice of top concentrations:

not specified

Vehicle controls validity:

valid

Untreated negative controls validity:

valid

True negative controls validity:

not specified

Positive controls validity:

valid

Key result

Species / strain:

S. typhimurium TA 1538

Metabolic activation:

with and without

Genotoxicity:

negative

Cytotoxicity / choice of top concentrations:

not specified

Vehicle controls validity:

valid

Untreated negative controls validity:

valid

True negative controls validity:

not specified

Positive controls validity:

valid

Remarks on result:

other: all strains/cell types tested

Remarks:

Migrated from field 'Test system'.

Executive summary:

method: Ames test with Salmonela typhimurium TA 98, TA 100, TA 1535, TA 1537, TA 1538

with and without metabolic activation

result: negative

Reference 3

Endpoint:

in vitro gene mutation study in bacteria

Type of information:

experimental study

Adequacy of study:

key study

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: well documented and scientifically acceptable

Qualifier:

equivalent or similar to guideline

Guideline:

OECD Guideline 472 (Genetic Toxicology: Escherichia coli, Reverse Mutation Assay)

GLP compliance:

yes

Type of assay:

bacterial reverse mutation assay

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:

0.0032 to 4.0 µg/plate

Vehicle / solvent:

no data

Key result

Species / strain:

E. coli WP2 uvr A

Metabolic activation:

with and without

Genotoxicity:

negative

Cytotoxicity / choice of top concentrations:

not specified

Vehicle controls validity:

valid

Untreated negative controls validity:

valid

Positive controls validity:

valid

Executive summary:

method: Ames test with E.coli WP 2 uvr A with and without metabolic activation

result: negative

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed (negative)

Genetic toxicity in vivo

Endpoint conclusion

Endpoint conclusion:

no study available

Additional information

Table 7.6.1/1 : Summary of genotoxicity tests:

 

Test n°	Test Guideline / Reliability	Focus	Strains  / cells tested	Metabolic activation	Test concentration	Statement
1 (Engelbart, 1980a)	Ames Test (eq. OECD 471, non-GLP) K, rel.2	Gene mutation	S. thyphimurium TA 1535, TA 1537, TA 1538, TA 98, TA 100	-S9 +S9	up to 4 µg/plate	-S9: not mutagenic + S9: not mutagenic
2(Engelbart, 1980b)	Ames Test (eq. OECD 471, non-GLP) K, rel.2	Gene mutation	E. coli WP2 WP2 urvA	-S9 +S9	up to 4 µg/plate	-S9: not mutagenic + S9: not mutagenic
3 (Mueller, 1989)	CAT (eq. OECD 473, non-GLP) K, rel.2	Chromosomal aberration	CHO/V79	-S9 +S9	Up to 20 µg/mL (-S9), up to 50 µg/mL (+S9) (cytotoxic concentration)	-S9: not clastogenic + S9: not clastogenic

Gene mutation Assay (Test n° 1)

Two bacterial reverse mutation assay (Ames test) were performed with the substance (Test n°1 and 2). Both studies wereused to conclude on the potential of the substance to induce gene mutation in bacteria.

No significant increases in the frequency of revertant colonies were recorded for any of the bacterial strains with any dose of test material, either in the presence or absence of metabolic activation. The tests indicate that the substance does not induce gene mutations in bacteria whereas all positive control chemicals (with and without metabolic activation) induced significant increase of colonies. The substance is therefore considered as non-mutagenic according to the Ames test. 

 

Chromosomal aberration (Test n°2)

The clastogenic potential of the substance was determined using an in vitro chromosome aberration test in Chinese hamster ovary cells, which measures the potential of a substance to increase the incidence the of structural chromosome aberrations in cultured Chinese hamster ovary cells. None of the dose levels up to the cytotoxicity limit with the substance, either in the presence or absence of metabolic activation, induced significant increases in the frequency of cells with aberrations in either of two experiments, whereas both positive control chemicals (with and without metabolic activation) induced significant increases in the frequency of aberrant cells. The substance is therefore considered as negative for inducing chromosomal mutations in Chinese hamster ovary cells under activation and non-activation conditions used in this assay.

Justification for classification or non-classification

Harmonised classification: 

The substance has no harmonised classification for genetic toxicity according to the Regulation (EC) No. 1272/2008 (CLP). 

 

Self-classification: 

Based on the available information, no additional classification is proposed according to the CLP and the GHS.