Ammonium fluoride

Genetic toxicity: in vitro

Administrative data

Endpoint:

in vitro cytogenicity / chromosome aberration study in mammalian cells

Remarks:

Type of genotoxicity: chromosome aberration

Type of information:

migrated information: read-across from supporting substance (structural analogue or surrogate)

Adequacy of study:

key study

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: Meets generally accepted scientific standards and accepatble for assessment - restrictions: incomprehensive reporting

Data source

Reference

Reference 1

Reference Type:

publication

Title:

Primary mutagenicity screening of food additives currently used in Japan

Author:

Ishidate M. Jr., Sofuni T., Yoshikawa M., Nohmi T., Sawada M., Matsuoka A.

Year:

1984

Bibliographic source:

Fd. Chem. Toxic., 22: 623-636

Reference 2

Reference Type:

publication

Title:

A comparative analysis of data on the clastogenicity of 951 chemical substances tested in mammalian cell cultures

Author:

Ishidate M. Jr., Harnois MC., and Sofuni T.

Year:

1988

Bibliographic source:

Mutat. Res., 195: 151-213

Reference 3

Reference Type:

publication

Title:

Micronucleus tests in mice on 39 food additives and eight miscellaneous chemicals

Author:

Hayashi, M., Kishi, M., Sofuni, T. and Ishidate, M.

Year:

1988

Bibliographic source:

Food and Chemical Toxicology 26(6): 487-500

Reference 4

Reference Type:

review article or handbook

Title:

SIDS Initial Assessment Report For SIAM 17 - Ammonium Chloride (12125-02-9)

Author:

OECD SIDS

Year:

2004

Bibliographic source:

UNEP Publications

Report date:

2004

Reference 5

Reference Type:

review article or handbook

Title:

Unnamed

Year:

2010

Report date:

2010

Materials and methods

Principles of method if other than guideline:

According to the method Ishidate, M.,Jr. und Odashima, S.: Mutation Research 48, 337

GLP compliance:

not specified

Type of assay:

in vitro mammalian chromosome aberration test

Test material

Test material information

Constituent 1

Reference substance name:

Ammonium chloride

EC Number:

235-186-4

EC Name:

Ammonium chloride

Cas Number:

12125-02-9

IUPAC Name:

ammonium chloride

Details on test material:

- Name of test material (as cited in study report): Ammonium chloride
- Source: Japan Food Additives Association, Tokyo
- Analytical purity: 99.7%

Method

Target gene:

not applicable

Species / strain

Species / strain / cell type:

other: Chinese hamster lung fibroblasts (CHL)

Details on mammalian cell type (if applicable):

- Origins: The cell line was originally established from the lung of a newborn female at the Cancer Research Institute, Tokyo
- Modal number: 25
- Doubling time 15 hours

Metabolic activation:

without

Test concentrations with justification for top dose:

The authors reported that three doses were tested. However, results for only two doses were reported
- 0.3 and 0.4 mg/ml. The third dose tested could not be identified

Vehicle / solvent:

physiol. saline

Controls

Untreated negative controls:

yes

Remarks:

(untreated cells)

Negative solvent / vehicle controls:

yes

Positive controls:

yes

Remarks:

In the study a total of 242 substances were tested. Of these substances, 54 were positive for causing chromosomal aberration, of which some have been shown to be also positive for carcinogenicity in rodents.

Positive control substance:

other: example of positively tested substance (chromosomal aberration + carcinogenicity): potassium bromate

Remarks:

Based on arguments cited above, the test system is considered to be adequatedly sensitive in distinguishing between substance capable of causing chromosomal aberration and substances not causing chromosomal aberration.

Details on test system and experimental conditions:

DURATION
- Exposure duration: 24 and 48 hours

SPINDLE INHIBITOR (cytogenetic assays):
- Name: Colcemid
- Concentration: 0.2 µg/ml
- Time schedule for addition: 2 hours before harvesting

STAIN: Giemsa solution (1.5%, at pH 6.8; E. Merck) for 12-15 mins

NUMBER OF REPLICATIONS: In case no dose dependency was found in the first experiment, a repeat experiment was performed at similar dose levels

NUMBER OF CELLS EVALUATED: 100 well spread metaphases
The incidence of polyploid cells as well as cells with structural chromosomal aberrations such as chromatid or chromosomal gaps, breaks, exchanges, ring formations, fragmentations, and others, was recorded for each culture plate.

Evaluation criteria:

The result was considered to be
- negative if the incidence of aberration is less than 4.9%.
- ambiguous if the incidence of aberration is between 5.0-9.9%.
- positive if the incidence of aberration is above 10%.

Results and discussion

Test results

Species / strain:

other: Chinese hamster lung fibroblasts (CHL) cells

Metabolic activation:

without

Genotoxicity:

positive

Cytotoxicity / choice of top concentrations:

not specified

Vehicle controls validity:

valid

Untreated negative controls validity:

valid

Positive controls validity:

valid

Additional information on results:

RANGE-FINDING/SCREENING STUDIES:
- The maximum dose chosen was based on the cytotoxicity and osmolarity. The maximum dose chosen for the main study was the concentration needed for 50% cell growth inhibition, estimated using a cell dosimeter (Monocellater, Olympus Co. Ltd.).

Remarks on result:

other: all strains/cell types tested

Remarks:

Migrated from field 'Test system'.

Any other information on results incl. tables

The incidence of aberration in the untreated and solvent control was about 3.0%. The incidence of cells with structural chromosomal aberrations at 0.4 mg/ml after 48hr treatment was 47.0%. The incidences of structural aberrations at 0.3 mg/ml after 24 hours and 48 hours of exposure were 11.0% and 30%, respectively.

Applicant's summary and conclusion

Conclusions:

Interpretation of results (migrated information):
positive without metabolic activation