Allyl isothiocyanate

Endpoint summary

Key value for chemical safety assessment

Genetic toxicity in vitro

Description of key information

Overall, both positive and negative results have been observed with AITC in genotoxicity tests in bacterial and mammalian cells in vitro in the absence of metabolic activation, with positive results occurring usually at or near cytotoxic concentrations.

Link to relevant study records

Reference

Reference 1

Endpoint:

in vitro gene mutation study in bacteria

Type of information:

experimental study

Adequacy of study:

key study

Study period:

1980

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

study well documented, meets generally accepted scientific principles, acceptable for assessment

Principles of method if other than guideline:

The mutagenicity of isothiocyanates and related compounds was tested by the method of Ames et al. with some modifications.

GLP compliance:

not specified

Type of assay:

bacterial reverse mutation assay

Species / strain / cell type:

S. typhimurium TA 100

Species / strain / cell type:

S. typhimurium, other: TA1535, TA1537,TA1538

Metabolic activation:

with and without

Metabolic activation system:

S-9 Mix

Vehicle / solvent:

DMSO

Species / strain:

S. typhimurium, other: TA100, TA98

Metabolic activation:

without

Genotoxicity:

positive

Cytotoxicity / choice of top concentrations:

not specified

Vehicle controls validity:

not specified

Untreated negative controls validity:

not specified

Positive controls validity:

not specified

Species / strain:

S. typhimurium, other: TA1535, TA1537, TA1538

Metabolic activation:

not specified

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:

There was no activating effect on mutagenicity by the pretreatment of these samples with S-9 Mix.

Conclusions:

It was found that all of the isohiocyanates tested showed mutagenicity on Salmonella typhimurium TA100, though the degree varied with each sample. Especially, allyl isothiocyanate have the highest potency among these compunds.

Reference 2

Endpoint:

in vitro cytogenicity / chromosome aberration study in mammalian cells

Type of information:

experimental study

Adequacy of study:

key study

Study period:

1987

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

data from handbook or collection of data

Principles of method if other than guideline:

Results from the testing of 108 coded chemicals in Chinese hamster ovary (CHO) cells for the induction of chromosome aberrations and sister chromatid exchanges (SCEs) are presented. All chemicals were tested with and without exogenous metabolic activation, using protocols designed to allow testing up to toxic doses.

GLP compliance:

not specified

Type of assay:

in vitro mammalian cell transformation assay

Species / strain / cell type:

Chinese hamster Ovary (CHO)

Metabolic activation:

with and without

Metabolic activation system:

S9 mix

Species / strain:

Chinese hamster Ovary (CHO)

Metabolic activation:

with and without

Genotoxicity:

positive

Remarks:

Weakly positive

Cytotoxicity / choice of top concentrations:

not specified

Conclusions:

The aberration test was weakly positive, with increases primarily in simple deletions. A chromosome aberration test in Chinese hamster cells with and without S9 was also reported by Kamasaki et al. (1982).

Reference 3

Endpoint:

genetic toxicity in vitro, other

Remarks:

Sister Chromatid Exchange

Type of information:

experimental study

Adequacy of study:

supporting study

Study period:

1987

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

data from handbook or collection of data

Principles of method if other than guideline:

Results from the testing of 108 coded chemicals in Chinese hamster ovary (CHO) cells for the induction of chromosome aberrations and sister chromatid exchanges (SCEs) are presented. All chemicals were tested with and without exogenous metabolic activation, using protocols designed to allow testing up to toxic doses.

GLP compliance:

not specified

Type of assay:

sister chromatid exchange assay in mammalian cells

Species / strain / cell type:

Chinese hamster Ovary (CHO)

Metabolic activation:

with and without

Metabolic activation system:

S9 Mix

Conclusions:

In the SCE test without S9, there was evidence for a trend, but no responses were elevated 20% over the control level. With S9, a more convincing increase in SCEs was seen. Polyploid cells were noted at 0.16 pg/ml or more without S9 and at 0.5 pg/ml or more with S9.

Reference 4

Endpoint:

in vitro gene mutation study in bacteria

Type of information:

experimental study

Adequacy of study:

key study

Study period:

1982

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

study well documented, meets generally accepted scientific principles, acceptable for assessment

Principles of method if other than guideline:

The mutagenicity test was conducted in the Salmonella/microsome mutagenicity assay on plates according to the method of Ames (Ames et al., 1975), with the S. typhimurium histidine (-) mutants, TA98 and TA100.

GLP compliance:

not specified

Type of assay:

bacterial reverse mutation assay

Species / strain / cell type:

S. typhimurium TA 100

Species / strain / cell type:

S. typhimurium TA 98

Metabolic activation:

with and without

Metabolic activation system:

S9 mix

Vehicle / solvent:

DMSO

Species / strain:

S. typhimurium, other: TA 98 and TA100

Metabolic activation:

with and without

Genotoxicity:

negative

Cytotoxicity / choice of top concentrations:

not specified

Conclusions:

In the mutation test none of the flavorings exhibited significant induction of his + revertants in Salmonella typhimurium TA98 or TA100, either with or without rat liver microsome as the metabolic activation system.

Reference 5

Endpoint:

in vitro cytogenicity / chromosome aberration study in mammalian cells

Type of information:

experimental study

Adequacy of study:

key study

Study period:

1982

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

study well documented, meets generally accepted scientific principles, acceptable for assessment

Principles of method if other than guideline:

CH cell line B241 was used it for the chromosome test in culture stages between the 5th and 8th passages. Exponentially growing cells at one day after seeding were exposed to each of the chemicals for 24 h, and then incubated another 24 h without the chemicals followed by treatment with colchicine (1 x 10 - 7 M) for 2-3 h.

GLP compliance:

not specified

Type of assay:

other: chromosome aberration test

Vehicle / solvent:

Chemicals were dissolved in DMSO at a concentration of 50 mM and then were diluted with the medium.

Species / strain:

other: Chinese-hamster B241 cells

Metabolic activation:

with and without

Genotoxicity:

positive

Cytotoxicity / choice of top concentrations:

not specified

Vehicle controls validity:

not specified

Untreated negative controls validity:

not specified

Positive controls validity:

not specified

Conclusions:

The results of the chromosome test showed significant increases in chromosome aberrations in the Chinese-hamster B241 cells by 8 out of the 9 agents, regardless of the presence or absence of S9 mix. In particular, trcinnamaldehyde (tr-CA) and allylisothiocyanate (AITC) exhibited high potentials for inducing aberrations. The total frequency of the aberrations indicated a dose dependent increase at a certain dose range.

Reference 6

Endpoint:

in vitro gene mutation study in bacteria

Type of information:

experimental study

Adequacy of study:

supporting study

Study period:

1982

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

study well documented, meets generally accepted scientific principles, acceptable for assessment

Principles of method if other than guideline:

reverse mutations in Eschericia coli WP67

GLP compliance:

not specified

Type of assay:

bacterial reverse mutation assay

Species / strain / cell type:

E. coli, other: Wp67 (trp uvrA polA)

Metabolic activation:

with and without

Species / strain:

E. coli, other: WP67 (trp uvrA polA)

Metabolic activation:

with

Genotoxicity:

positive

Additional information on results:

The authors noted that the degree of mutagenicity was related to the source and protein content of the metabolic activation system. Microsomal fractions from the liver of phenobarbital-treated rats, goats and monkeys were reported to be more active at a lower protein content than those prepared from mice and hamsters.

Conclusions:

AITC induced reverse mutations in Eschericia coli WP67 (trp uvrA polA) only in the presence of metabolic activation in an assay with 120 minutes incubation (Rihová, 1982). Bacteriotoxicity was higher in the absence of metabolic activation than in the presence. The authors noted that the degree of mutagenicity was related to the source and protein content of the metabolic activation system. Microsomal fractions from the liver of phenobarbital-treated rats, goats and monkeys were reported to be more active at a lower protein content than those prepared from mice and hamsters.

Reference 7

Endpoint:

in vitro cytogenicity / chromosome aberration study in mammalian cells

Type of information:

experimental study

Adequacy of study:

key study

Study period:

1985

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

study well documented, meets generally accepted scientific principles, acceptable for assessment

Principles of method if other than guideline:

induction of chromosomal aberrations in Chinese hamster ovary cells

GLP compliance:

not specified

Type of assay:

other: chromosomal aberration

Species / strain:

Chinese hamster Ovary (CHO)

Metabolic activation:

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

Conclusions:

An induction of chromosomal aberrations in Chinese hamster ovary cells which were exposed to AITC concentrations up to 10 nmol/l (0.99 ng/ml) without metabolic activation was reported by Kasamaki et al. (1982) and Kasamaki and Urasawa (1985).

Endpoint conclusion

Endpoint conclusion:

no study available (further information necessary)

Genetic toxicity in vivo

Description of key information

In vivo, the results were consistently negative in assays for micronucleus formation in mice and rats and unscheduled DNA synthesis in rats after oral application as well as in a dominant lethal mutation assay in mice after intraperitoneal injection.

Link to relevant study records

Reference

Reference 1

Endpoint:

in vivo mammalian somatic cell study: cytogenicity / erythrocyte micronucleus

Type of information:

experimental study

Adequacy of study:

key study

Study period:

1993

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

study well documented, meets generally accepted scientific principles, acceptable for assessment

Qualifier:

according to guideline

Guideline:

OECD Guideline 474 (Mammalian Erythrocyte Micronucleus Test)

Deviations:

yes

Remarks:

Only a single sex was used.

GLP compliance:

not specified

Species:

mouse

Strain:

B6C3F1

Sex:

male

Route of administration:

intraperitoneal

Vehicle:

Each chemical was prepared in the appropriate solvent (PBS for water soluble chemicals, corn oil for water-insoluble chemicals).

Duration of treatment / exposure:

Three consecutive day

Frequency of treatment:

Daily

Post exposure period:

48 hr after the third treatment, the surviving mice were euthanized

Dose / conc.:

37.5 mg/kg bw/day (nominal)

Dose / conc.:

75 mg/kg bw/day (nominal)

Dose / conc.:

150 mg/kg bw/day (nominal)

No. of animals per sex per dose:

Groups of 5 mice were administered the test chemicals.

Control animals:

yes

Sex:

male

Genotoxicity:

negative

Toxicity:

no effects

Vehicle controls validity:

valid

Conclusions:

AITC did not increase the number of micronuclei in bone marrow cells.

Reference 2

Endpoint:

in vivo mammalian cell study: DNA damage and/or repair

Type of information:

experimental study

Adequacy of study:

supporting study

Study period:

1998

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

study well documented, meets generally accepted scientific principles, acceptable for assessment

Principles of method if other than guideline:

Allylisothiocyanate (AITC) has been evaluated for its ability to initiate unscheduled DNA synthesis (UDS) in the livers of male rats in vivo. Specific Pathogen Free
outbred albino Hsd/Ola Sprague-Dawley rats were exposed by oral gavage to 37.5 or 125 mg/kg AITC in corn oil and hepatocytes assessed for UDS by autoradiography 2 and 14 h later.

GLP compliance:

not specified

Type of assay:

unscheduled DNA synthesis

Species:

rat

Strain:

Sprague-Dawley

Details on species / strain selection:

Specific Pathogen Free outbred albino Hsd/Ola Sprague-Dawley rats were treated.

Sex:

male

Route of administration:

oral: gavage

Vehicle:

corn oil.

Details on exposure:

A dose level of 125 mg/kg bodyweight was found to be the maximum tolerated dose under the conditions of this test. Clinical signs occurred in the 250 and 500 mg/kg body weight dose groups accompanied by mortality of one and two of four animals in each group, respectively. A dosage of 125 mg/kg body weight was therefore chosen as the maximum for use in the DNA repair test.

Duration of treatment / exposure:

Once

Dose / conc.:

37.5 mg/kg bw/day (nominal)

Dose / conc.:

125 mg/kg bw/day (nominal)

Control animals:

yes, concurrent vehicle

Positive control(s):

Animals in the positive control group were treated with dimethylnitrosamine at 4 mg/kg for the 2 h expression or 2-acetylaminofluorene at 50 mg/kg for the 14 h expression.

Tissues and cell types examined:

Hepatocytes were isolated from each rat by enzymatic dissociation of the liver.

Sex:

male

Genotoxicity:

negative

Toxicity:

no effects

Vehicle controls validity:

valid

Positive controls validity:

valid

Conclusions:

AITC did not induce UDS at either dose level at either time point. These data are consistent with all other evidence indicating that AITC does not act as a genotoxin in vivo.

Reference 3

Endpoint:

in vivo mammalian germ cell study: cytogenicity / chromosome aberration

Type of information:

experimental study

Adequacy of study:

supporting study

Study period:

1972

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

study well documented, meets generally accepted scientific principles, acceptable for assessment

Qualifier:

according to guideline

Guideline:

OECD Guideline 478 (Genetic Toxicology: Rodent Dominant Lethal Test)

Deviations:

yes

Remarks:

lower number of animals and of dose levels used, limited report of experimental observations.

GLP compliance:

not specified

Type of assay:

rodent dominant lethal assay

Species:

mouse

Strain:

Swiss

Sex:

male/female

Route of administration:

intraperitoneal

Dose / conc.:

3.8 mg/kg bw/day (nominal)

Dose / conc.:

19 mg/kg bw/day (nominal)

No. of animals per sex per dose:

7 male rats/ 3.8 mg/kg
9 male rats/19 mg/kg

Control animals:

yes, concurrent vehicle

Conclusions:

AITC was investigated in a dominant lethal mutation assay. The substance was administered to male ICR/Ha Swiss mice as a single intraperitoneal injection at doses of 3.8 or 19 mg/kg bw. The incidence of early fetal death or pre-implantation losses in females mated with the treated males was not increased over a period of eight weeks

Reference 4

Endpoint:

in vivo mammalian somatic cell study: cytogenicity / erythrocyte micronucleus

Type of information:

experimental study

Adequacy of study:

supporting study

Study period:

1988

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

study well documented, meets generally accepted scientific principles, acceptable for assessment

Principles of method if other than guideline:

Allyl isothiocyanatc (AITC) was given in doses of 0, 10, 20, or 40 mg/kg (5 days/week) by oral intubation to male rats for up to 6 weeks.

GLP compliance:

not specified

Species:

rat

Strain:

other: Shoe: WIST

Sex:

male

Route of administration:

oral: gavage

Vehicle:

Paraffin oil

Duration of treatment / exposure:

Up to 6 weeks

Frequency of treatment:

daily

Dose / conc.:

10 mg/kg bw/day (nominal)

Dose / conc.:

20 mg/kg bw/day (nominal)

Dose / conc.:

40 mg/kg bw/day (nominal)

Control animals:

yes, concurrent vehicle

Conclusions:

Cell number, and the percentage of polychromatic erythrocytes and erythrocytes with micronuclei in the femoral marrow, indicative of the clastogenicity of chemicals, were not affected.

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed (negative)

Justification for classification or non-classification

According to the available information and in particular according to in vivo study results, AITC is not classified as genotoxic.