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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
Type of information:
experimental study
Adequacy of study:
weight of evidence
Study period:
This study was accepted for publication on 17 October 1983
Reliability:
2 (reliable with restrictions)
Rationale for reliability incl. deficiencies:
data from handbook or collection of data
Remarks:
Reliability 2 was assigned as the study was conducted to a recognised procedure it is a comparative study with no clear endpoint data.

Data source

Reference
Reference Type:
publication
Title:
Unnamed
Year:
1983

Materials and methods

Test guideline
Qualifier:
no guideline followed
Principles of method if other than guideline:
The micronucleus test was performed in mice according to the established procedures (Schmid, 1976; Heddle and Salamone, 1981). Male and female mice were given the test compounds orally, dissolved in polyethyleneglycol (PEG 400), in doses up to acutely toxic levels. 24 h after this single dose, the mice were sacrificed and the bone marrow cells were flushed out into foetal calf serum. In the case of a negative outcome of the test, a second assay was performed with fixation times of 24, 48, and 72 h, resp. After centrifugation at 400 g, the cells were spread onto slides, air-dried and stained with May-Grünwald/Giemsa. In this case, the slides were coded and analysed by two individuals separately.
GLP compliance:
no
Type of assay:
other: Chromosomal aberration

Test material

Reference
Name:
Unnamed
Type:
Constituent
Test material form:
liquid: viscous
Specific details on test material used for the study:
Resorcinoi diglycidyl ether (RDGE) was synthesized according to pub- lished methods (Ross et al., 1964); briefly, the parent compounds, N-methylaniline, aniline, and resorcinol, resp., were first reacted with an approximately 10-fold excess of epichloro- hydrin at slightly elevated temperatures. Upon completion of the reaction, a 50% sodium hydrox- ide solution was added slowly over a period of 1-3h in an amount equivalent to the number of reactive sites. The product was finally dissolved in toluene, washed with water and dried over anhydrous sodium sulfate. The solvent was then removed in vacuo and the product was purified by vacuum distillation. The purified product was analyzed by HPLC (on a silica column, with the same solvent as above) and was estimated to contain less than 2% impurities. The alkylating potency of the epoxide was measured in the 4-(4-nitro-benzyl)pyridine (NBP) assay according to Friedman and Boger (1961).

Test animals

Species:
mouse
Strain:
ICR
Sex:
male/female
Details on test animals and environmental conditions:
Mice of the ICR-strain were obtained from the Institute of Animal Husbandry of the University of Zurich

Administration / exposure

Route of administration:
oral: gavage
Vehicle:
Polyethylene glycol (PEG 400)
Details on exposure:
Male and female mice of body weight circa 25 g, were given the test compounds orally, dissolved in polyethylene-glycol (PEG 400), in doses up to acutely toxic levels.
Duration of treatment / exposure:
once
Frequency of treatment:
once
Post exposure period:
24h
Doses / concentrationsopen allclose all
Dose / conc.:
300 mg/kg bw (total dose)
Remarks:
first assay: 24 after single dose
Dose / conc.:
600 mg/kg bw (total dose)
Remarks:
second assay was performed with fixation times of 24, 48 and 72 h
No. of animals per sex per dose:
4 males and 4 females
Control animals:
no

Examinations

Tissues and cell types examined:
polychromatic erythrocytes from the bone marrow
Details of tissue and slide preparation:
24 h after this single dose, the mice were sacrificed and the bone marrow cells were flushed out into foetal calf serum. In the case of a negative outcome of the test, a second assay was performed with fixation times of 24, 48, and 72 h, resp. After centrifugation at 400 g, the cells were spread onto slides, air-dried and stained with May-Grtinwald/ Giemsa.
Evaluation criteria:
Not specified
Statistics:
There the standard deviation of the frequency of micronucleated erythrocytes (per thousand polychromatic erythrocytes) was calculated. The spontaneous frequency of micronucleated polychromatic erythrocytes (3-5 per thousand polychromatic erythrocytes, standard deviation 1.8) has been subtracted.

Results and discussion

Test results
Key result
Sex:
male/female
Genotoxicity:
negative
Toxicity:
yes
Remarks:
one out of four mice died within 48 h in each group
Vehicle controls validity:
not specified
Negative controls validity:
not specified
Positive controls validity:
not specified
Additional information on results:
Mice were given solutions of the test compound orally in dosages up to the LD50, and the polychromatic erythrocytes from the bone marrow of such treated animals were checked for the presence of micronuclei. The in vitro much more active RDGE, on the other hand, proved to be completely inactive. The inability of RDGE to induce micronuclei in the bone marrow of mice in vivo could not be traced to some influence on the length of the cell cycle, since the compound was also inactive at 48 and 72 h after dosage, nor was the dose given insufficient, since 1 out of 4 mice died within 48 h in each experimental group.

Any other information on results incl. tables

Table 1 INDUCTION OF MICRONUCLEATED POLYCHROMATIC ERYTHROCYTES 1N THE BONE MARROW OF MICE TREATED WITH RESORCINOL DIGLYCIDYL ETHER

 Fixation Time (h)

 Frequency (and standard deviation) of micronucleated erythrocytes (per thousand polychromatic erythrocytes) at dose (mg/kg p.o.) of                   

   300  400  500  600  800  1000  1500
 24  0.0 (1.5)      0.0 (1.9)      
 48        0.9 (1.3)      
 72        0.4 (0.6)      

The spontaneous frequency of micronucleated polychromatic erythrocytes (3-5 per thousand polychromatic erythrocytes, standard deviation 1.8) has already been subtracted.

Applicant's summary and conclusion

Conclusions:
The article has demonstrated that resorcinol diglycidyl ether (RDGE) was completely inactive in vivo micronucleus assay in mice.
Executive summary:

The micronucleus test was performed in male and female mice of the ICR-strain. The test item resorcinol diglycidyl ether (RDGE) dissolved in polyethylene-glycol (PEG 400) was given orally in doses up to acutely toxic level. 24 h after the single dose (300 mg/kg po), the mice were sacrificed and the bone marrow cells were flushed out into foetal clf serum. In the case of negative outcome of the test, a second assay was performed with fixation times of 24, 48 and 72 h, respectively. After centrifugation at 400 g, the cells were spread onto slides, air-dried and stained with May-Grünwald/Giemsa. The slides were coded and analysed by two individuals separately. The polychromatic erythrocytes from the bone marrow of treated animals were checked for the presence of micronuclei. RDGE proved to be completely inactive. The inability of RDGE to induce micronuclei in the bone marrow of mice in vivo could not be traced to some influence on the length of the cell cycle, since the compound was also inactive at 48 and 72 h after dosage, nor was the dose given insufficient, since 1 out of 4 mice died within 48 h.