Registration Dossier

Administrative data

Endpoint:
in vivo mammalian cell study: DNA damage and/or repair
Remarks:
Type of genotoxicity: DNA damage and/or repair
Type of information:
experimental study
Adequacy of study:
key study
Reliability:
2 (reliable with restrictions)

Data source

Reference
Reference Type:
publication
Title:
Testing of 24 Foods, Drug, Cosmetic, and Fabric Dyes in the In Vitro and the In Vivo/ In Vitro Rat Hepatocyte Primary Culture/ DNA Repair Assays
Author:
Douglas Kornbrust and Thomas Barfknecht
Year:
1985
Bibliographic source:
Environmental Mutagenesis 7:101-120 (1985)

Materials and methods

Test guideline
Qualifier:
according to
Guideline:
other: as mentioned below
Principles of method if other than guideline:
DNA damage and/or repair toxicity performed on Sprague Dawley cesarean-derived rats
GLP compliance:
no
Type of assay:
other: In Vivo/ In Vitro Rat Hepatocyte Primary Culture/ DNA Repair Assays

Test material

Reference
Name:
Unnamed
Type:
Constituent
Type:
Constituent
Details on test material:
- Name of test material (as cited in study report): Food black (2519-30-4)- Molecular formula (if other than submission substance): Not applicable- Molecular weight (if other than submission substance): Not applicable- Substance type: organic - Physical state: solid- Purity: 95%- Impurities (identity and concentrations):5%

Test animals

Species:
rat
Strain:
Sprague-Dawley
Sex:
male
Details on test animals and environmental conditions:
Details on test animals and env conditionsTEST ANIMALS- Source: No data available - Age at study initiation: No data available- Weight at study initiation: 200-300 g- Assigned to test groups randomly: [no/yes, under following basis: ] No data available- Fasting period before study: No data available- Housing: No data available- Diet (e.g. ad libitum): Diet (ad libitum)- Water (e.g. ad libitum): Water (ad libitum)- Acclimation period: No data availableENVIRONMENTAL CONDITIONS- Temperature (°C): No data available- Humidity (%):12-hr light/dark cycles- Air changes (per hr): No data available- Photoperiod (hrs dark / hrs light): 12-hr light/dark cyclesIN-LIFE DATES: From: To: No data available

Administration / exposure

Route of administration:
oral: gavage
Vehicle:
Aqueous solution Or corn oil
Details on exposure:
No data available
Duration of treatment / exposure:
At specific times prior to the isolation of hepatocytes
Frequency of treatment:
One
Post exposure period:
No data available
Doses / concentrations
Remarks:
Doses / Concentrations:500 mg/kgBasis:no data
No. of animals per sex per dose:
No data available
Positive control(s):
Solvent Yellow 3 (0-aminoazotoluene)

Examinations

Tissues and cell types examined:
Rat hepatocytes
Details of tissue and slide preparation:
No data available
Evaluation criteria:
Net nuclear grains (NNG) were determined by counting the number of grains in each nuclei and subtracting the average number of grains present in three equal-size adjacent cytoplasmic areas.Net nuclear grains (NNG) were measured are as follows:Average net nuclear grain counts of 5 or greater were assumed to constitute a positive response. For those dyes that produced responses between zero and 5 average net nuclear grains, it was generally not possible to demonstrate a statistically significant difference from the control value within a given experiment. Therefore, these responses were judged to be equivocal. Net nuclear grain counts below zero were considered negative responses.
Statistics:
No data available

Results and discussion

Test results
Sex:
male
Genotoxicity:
negative
Toxicity:
not specified
Vehicle controls validity:
not specified
Negative controls validity:
not specified
Positive controls validity:
not specified

Any other information on results incl. tables

- Statistical evaluation:

 

Responses Produced by Various Dyes in the In Vivo/In Vitro HPC/DR Assay

Dye

Dose

(mg/kg b.w.)

Time PTPa

(hr)

Avg. NNGb

Percent cells<5 NNG

Res-

ponse

Food Black 1

500

2

15

-0.7 (±3.3)

-1.5 (± 2.8)

5

3

N

aTime that dye was administered prior to start of liver perfusion and isolation of hepatocytes.

bAverage net nuclear grains (as defined in the Methods section); mean + standard deviation from 60 cells.

CPercent of cells with > 5 net nuclear grains.

dP. Positive; WP, weak positive; E, equivocal; N, negative (as per the criteria defined in the methods section).

Applicant's summary and conclusion

Conclusions:
Interpretation of results (migrated information): negativeThe genetic toxicity of Food black 1 (CAS No 2519-30-4) in Rat hepatocytes cell line was found to be negative.
Executive summary:

The genetic toxicity test was performed on rat using Food black 1.Rats given the 500 mg/kg ofFood black 1.Dye were administered to the animals as aqueous solutions or corn oil suspensions (for the non-water-soluble dyes), by gavage, at specific times prior to the isolation of hepatocytes.

Rat hepatocytes were isolated and cultured by the two-step in situ liver perfusion

Method.2 X 105viable hepatocytes were seeded into 25-mm wells and were allowed to attach to plastic cover slips for 2 hr.The cells were then incubated for 4 hr with [3H]-thymidine.

Net nuclear grains (NNG) were determined by counting the number of grains in each nuclei and subtracting the average number of grains present in three equal-size adjacent cytoplasmic areas.

Average net nuclear grain counts of 5 or greater were assumed to constitute apositiveresponse. For those dyes that produced responses between zero and 5 average net nuclear grains, it was generally not possible to demonstrate a statistically significant difference from the control value within a given experiment. Therefore, these responses were judged to beequivocal. Net nuclear grain counts below zero were considerednegativeresponses.

From the above table it was found that Avg. NNG forFood black 1 was found to be below zero.

 

Therefore, from the study in vivogenetic toxicity of Food black 1 (CAS No 2519-45-9)was found to be negative.