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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:
1987-03-02 to 1987-10-23
Reliability:
1 (reliable without restriction)
Rationale for reliability incl. deficiencies:
other: Guideline study

Data source

Reference
Reference Type:
study report
Title:
Unnamed
Year:
1987
Report date:
1987

Materials and methods

Test guidelineopen allclose all
Qualifier:
according to guideline
Guideline:
OECD Guideline 475 (Mammalian Bone Marrow Chromosome Aberration Test)
Qualifier:
according to guideline
Guideline:
EU Method B.11 (Mutagenicity - In Vivo Mammalian Bone-Marrow Chromosome Aberration Test)
GLP compliance:
yes
Type of assay:
chromosome aberration assay

Test material

Constituent 1
Chemical structure
Reference substance name:
2,2,4(or 2,4,4)-trimethylhexane-1,6-diamine
EC Number:
247-063-2
EC Name:
2,2,4(or 2,4,4)-trimethylhexane-1,6-diamine
Cas Number:
25513-64-8
Molecular formula:
C9H22N2
IUPAC Name:
2,2,4-trimethylhexane-1,6-diamine; 2,4,4-trimethylhexane-1,6-diamine
Test material form:
liquid
Details on test material:
Batch: botteld on October 31st 1986

Test animals

Species:
hamster, Chinese
Strain:
other: Han-Chinese
Sex:
male/female
Details on test animals or test system and environmental conditions:
TEST ORGANISMS: 
- Age: 3 to 4 months
- Source: Zentralinstitut für Versuchstierkunde, Hannover (Germany)
- Weight at study initiation: males 30 to 40 g; females 27 to 55 g
- No. of animals per dose: 5 males + 5 females
- Diet: Ssniff R pelleted diet, ad libitum
- Water: ad libitum, controlled visually
- Acclimation period: 4 weeks
ENVIRONMENTAL CONDITIONS
- Temperature (°C): 21,5 C +- 1,5 C
- Humidity (%): 65 % +- 10 %
- Air changes (per hr): 16 times per hour
- Photoperiod (hrs dark / hrs light): 12 hours daily from 7.00 a.m. to 7.00 p.m.

Administration / exposure

Route of administration:
intraperitoneal
Vehicle:
water
Details on exposure:
ADMINISTRATION: 
- Vehicle: water (aqua ad injectabilia); 10 ml/kg bw applied
- Duration of test: 24 hours; 22 hours after application: Treatment with  3.3 mg colcemid/kg bw
- Control groups and treatment:   
Positive: 20 mg cyclophosphamide/kg bw   
Negative: Vehicle
Duration of treatment / exposure:
single dose
Frequency of treatment:
1 time
Post exposure period:
24 hours
Doses / concentrations
Remarks:
Doses / Concentrations:
3.75; 15; 60 mg/kg bw
Basis:
nominal conc.
No. of animals per sex per dose:
5
Control animals:
yes, concurrent vehicle
Positive control(s):
20 mg cyclophosphamide/kg bw   

Examinations

Tissues and cell types examined:
EXAMINATIONS:    
Evaluation of 50 metaphase cells/animal (= 500/dose level)  
Mitotic index determined from 1000 cells/animal
Details of tissue and slide preparation:
Sampling times and number of samples: 24 hours after application:  Killing by cervical dislocation, removal of femurs, dislocation of  epiphysis, 
rinsing with Hanks solution (37 °C) from diaphysis to obtain  bone marrow, centrifugation, incubation for 20 minutes at 37 °C in 1 %  trisodium 
citrate, two times centrifugation / fixation in methanol/acetic  acid (3:1), drying, staining with Giemsa.
Evaluation criteria:
- Criteria for evaluating results: Significant increase of aberration  rate (as compared with the negative control) with at least one dose level.
Statistics:
The mitotic index was statistically compared using a one factorial analysis of variance with subsequent Scheffe-test.
Group mean values might be compared employing the U-test of Mann-Whitney (chromosomale aberrations)

Results and discussion

Test results
Sex:
male/female
Genotoxicity:
negative
Toxicity:
yes
Remarks:
Animals of the 60 mg/kg bw dose group showed transient and slight loss of activity.
Vehicle controls validity:
valid
Negative controls validity:
not applicable
Positive controls validity:
valid
Additional information on results:
MORTALITY: No animal died at any dose level.
CLINICAL SIGNS: Animals of the 60 mg/kg bw dose group showed transient  and slight loss of activity.
-------------------------------------------
MITOTIC INDEX AND CHROMOSOMAL ABERRATIONS (excl. gaps): 
-------------------------------------------
Dose level             % M.I.          % C.A.
-------------------------------------------   
neg. control         3.78             1.6   
pos. control          1.88 p<0.05    3.8 *    
3.75 mg/kg bw       4.02            1.0   
15 mg/kg bw          3.30           1.0   
60 mg/kg bw          3.98            0.6
* Borderline of significance; highly significant (p<0.001) result including gaps.

Any other information on results incl. tables

no further remarks

Applicant's summary and conclusion

Conclusions:
Interpretation of results (migrated information): negative
The results of this study indicate that under the test conditions, the test substance 2,2,4(or 2,4,4)-trimethylhexamethylenediamine did not induce chromosome aberrations in the bone-marrow of male and female Chinese Hamster.
Executive summary:

2,2,4(or 2,4,4)-trimethylhexamethylenediamine was tested for its ability to induce in vivo chromosomal aberrations in the bone marrow of Chinese Hamsters. Each 5 male and 5 female Chinese Hamsters were exposed to 3.75, 15.0, and 60.0 mg/kg/bw by intraperitoneal injection. Bone marrow were collected 24 hours after single treatment and metaphase cells were examined microscopically for chromosomal aberrations. The analyse of metaphase cells showed that the test substance 2,2,4(or 2,4,4)- trimethylhexamethylene diamine did not induce chromosome aberration in the bone-marrow of Chinese Hamsters. Therefore, 2,2,4(or 2,4,4)-trimethylhexa methylenediamine is considered to be non-mutagenic in this chromosome aberration assay.