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Toxicological information

Genetic toxicity: in vivo

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Administrative data

Endpoint:
in vivo mammalian somatic cell study: cytogenicity / bone marrow chromosome aberration
Remarks:
Type of genotoxicity: chromosome aberration
Type of information:
experimental study
Adequacy of study:
key study
Study period:
1.3.1975-25.2.1976
Reliability:
2 (reliable with restrictions)
Rationale for reliability incl. deficiencies:
other: Comparable to Guideline study study with acceptable restrictions.

Data source

Referenceopen allclose all

Reference Type:
study report
Title:
Unnamed
Year:
1976
Report Date:
1976
Reference Type:
publication
Title:
The development of a human amnion strain of cells.
Author:
Fernandes, M.V.
Year:
1956
Bibliographic source:
Texas Repts. Biol. Med., 16, 48.
Reference Type:
publication
Title:
Chromosome Cytology.
Author:
Moorhead, P.S. and P.C. Nowell
Year:
1964
Bibliographic source:
In Methods In Medical Research, H. N. Eisen, Ed. Yearbook Medical Publ., Inc., Chicago, p. 310.
Reference Type:
publication
Title:
Virus-cell interaction with tumor producing virus.
Author:
Vogt, M. and R. Dulbecco
Year:
1960
Bibliographic source:
Proc. Nat. Acad. Sci., 46, 365 - 370
Reference Type:
publication
Title:
Chromosome Praparations of Leukocytes Cultured from Humn Peripheral Blood
Author:
Moorhead, P.S:, Nowell, W.J., Mellman, W.J., Battips, D.M., Hunger, D.A.
Year:
1960
Bibliographic source:
Expt.Cell Res., 20: 613

Materials and methods

Test guideline
Qualifier:
equivalent or similar to
Guideline:
OECD Guideline 475 (Mammalian Bone Marrow Chromosome Aberration Test)
Principles of method if other than guideline:
Kidney cells from kidney tissue removed at autopsy were cultured by the trypsinization method of Fernandes (1958). Cultures were maintained in Eagle's medium as modified by Vogt and Dulbecco (1960). Cells were processed for spreading on slides by the method of Moorhead & Newell (1964). Slides were stained with Giemsa stain. Chromosomes were counted and morphological aberrations were examined from photographic negatives of up to 50 metaphase cells [ Lee, et al., (1976)].DEVIATIONS FROM OECD PROTOCOL #475. This study was carried out on rats that had been dosed in their diet for 5 and 13 weeks, respectively. The study also had no positive control. Two hundred cells were evaluated / rat for measuring cell ploidy. Kidney samples from fewer than five rats total were evaluated. The report does not specify whether the kidneys were from males, females, or both. Mitotic indices were not calculated.
GLP compliance:
not specified
Type of assay:
chromosome aberration assay

Test material

Reference
Name:
Unnamed
Type:
Constituent
Details on test material:
- Name of test material (as cited in study report): TNG, trinitroglycerin- Source: SDM No.17, Atlas Chemicals Division, ICI America Inc., Wilmington, Del.)- Physical state. a 10% mixture on lactose

Test animals

Species:
rat
Strain:
other: CD® rats
Sex:
male/female
Details on test animals and environmental conditions:
TEST ANIMALS- Source: Charles River Breeding Lab., Wilmington, Mass.- Fasting period before study: ad libitum- Housing: plastic cage with filter tops- Diet (e.g. ad libitum): ad libitum- Water (e.g. ad libitum): ad libitum- Acclimation period: 2 weeksENVIRONMENTAL CONDITIONS- Temperature (°C): 75+/-5°F- Humidity (%):50+/-10%- Air changes (per hr):10 air chenges per hour- Photoperiod (hrs dark / hrs light): 12-hour on and 12-hour off

Administration / exposure

Route of administration:
oral: feed
Vehicle:
- Vehicle(s)/solvent(s) used: lactose- Justification for choice of solvent/vehicle: TNG was desensitized in lactose.- Concentration of test material in vehicle: 10%
Details on exposure:
DIET PREPARATION- Rate of preparation of diet (frequency): weekly- Mixing appropriate amounts with (Type of food): standard rodent chow- Storage temperature of food: room temperature
Duration of treatment / exposure:
4 weeks or 13 weeks
Frequency of treatment:
24 hrs/day - The animal feeders were refilled after the 4th day and emptied completely after the 7th day before the freshly prepared TNG-feed mixture was used.
Post exposure period:
4 weeks
Doses / concentrationsopen allclose all
Remarks:
Doses / Concentrations:59 mg/kg/day Basis:nominal in dietmale average daily intake for first 5 weeks (from highest dose level), TNG intake was corrected for evaporation loss.
Remarks:
Doses / Concentrations:229.5 mg/kg/dayBasis:nominal in dietmale average daily intake for weeks 6-13, incl. (from highest dose level). TNG intake was corrected for evaporation loss.
Remarks:
Doses / Concentrations:59.3 mg/kg/dayBasis:nominal in dietfemale average daily intake for first 5 weeks (from highest dose level). TNG intake was corrected for evaporation loss.
Remarks:
Doses / Concentrations:233.8 mg/kg/dayBasis:nominal in dietfemale average daily intake for weeks 6-13, incl. (from highest dose level). TNG intake was corrected for evaporation loss.
No. of animals per sex per dose:
16 females and 16 males per dose
Control animals:
yes, concurrent vehicle

Examinations

Tissues and cell types examined:
kidney cultures
Details of tissue and slide preparation:
CRITERIA FOR DOSE SELECTION: Since the rat kidneys were from the highest dose group and the investigators concluded that there appeared to be no effect on the parameters measured, chromosome aberration analyses were not carried out on kidney cells from rats dosed at lower levels.KIDNEY CULTURESKidney tissue samples were removed at necropsy and cultured by the trypsinization method of Fernandes. All cultures were maintained in Eagle´s medium as modified by Vogt and Dulbecco.CHROMOSOME ANALYSISActively dividing kidney cultures and phytohemaglutin-stimulated lymphocytes were arrested in metaphase by short-term colchicine treatment. The cells were trypsinized, swollen in hypotonic solution and processed for spreading on glass slide by the method Moorhead and Nowell. Slides were stained with giemsa and scanned under low power optics. Cell polyploidy was estimated by examination of 200 cells. Slides showing minimum scattering of cells in metaphase were selected for analysis under oil immersion optics.
Evaluation criteria:
Chromosomes were counted and morphological aberration were examined from photographic negatives of up to 50 metaphase cells.

Results and discussion

Test results
Sex:
not specified
Genotoxicity:
negative
Vehicle controls validity:
not specified

Any other information on results incl. tables

Rat kidney cells

Daily dose (mg/kg)

No.of rats

Chromosome frequency

Tetraploids per 100 cells

40

41

42

43

44

WKS 1-5

 

 

 

 

 

 

 

0

4

41

4

42

1

0

0.59±0.192

Ave.59

3

3

1

44

1

0

0.65±0.33

WKS 6-13

 

 

 

 

 

 

 

0

4

4

4

42

1

0

0.59±0.19

Ave.229.5

4

4

2

43

1

0

0.75±0.25

1mean,2mean±standard error

Dose (mg/kg)

No. of rats

Chromatid breaks&gaps/50 cells

Translocations/50 cells

Total aberrations/50 cells

WKS 1-5

 

 

 

 

0

4

1.5±0.31

0.5±0.6

2±0.3

Ave.59

3

2±0.6

1±0.1

2±1.3

WKS 6-13

 

 

 

 

0

4

1.5±0.3

0.5±0.3

2±0.3

Ave.233.8

4

1±0.7

0.5±0.3

1.5±0.9

1mean

Applicant's summary and conclusion

Conclusions:
Interpretation of results (migrated information): negativeThe data are indicative, but incomplete by contemporary standards. There is no apparent suggestion of an effect, but the small number of control and test rats evaluated and the lack of information as to the sexes involved make statistical evaluation of the results questionable. The test animal standard errors usually were larger than those for the control animal physical aberration measurements, suggesting more scatter in the test animal measurements, but there does not appear to be any real suggestion of an effect.