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Toxicological information

Genetic toxicity: in vivo

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Administrative data

Endpoint:
in vivo mammalian somatic cell study: cytogenicity / erythrocyte micronucleus
Type of information:
experimental study
Adequacy of study:
key study
Reliability:
1 (reliable without restriction)
Rationale for reliability incl. deficiencies:
guideline study

Data source

Reference
Reference Type:
study report
Title:
Unnamed

Materials and methods

Test guideline
Qualifier:
according to guideline
Guideline:
OECD Guideline 474 (Mammalian Erythrocyte Micronucleus Test)
GLP compliance:
yes

Test material

Constituent 1
Chemical structure
Reference substance name:
2-(1,3-benzodioxol-5-ylamino)ethanol hydrochloride
EC Number:
303-085-5
EC Name:
2-(1,3-benzodioxol-5-ylamino)ethanol hydrochloride
Cas Number:
94158-14-2
Molecular formula:
C9H11NO3.ClH
IUPAC Name:
2-(1,3-benzodioxol-5-ylamino)ethanol hydrochloride
Test material form:
solid: crystalline

Test animals

Species:
mouse
Strain:
NMRI
Sex:
male/female

Administration / exposure

Route of administration:
intraperitoneal
Vehicle:
Distilled water
Duration of treatment / exposure:
Single administration 24 and 48 hours (high dose only) before sacrifice
Doses / concentrationsopen allclose all
Dose / conc.:
0 mg/kg bw/day
Remarks:
control group
Dose / conc.:
25 mg/kg bw/day
Dose / conc.:
125 mg/kg bw/day
Dose / conc.:
250 mg/kg bw/day
No. of animals per sex per dose:
5
Control animals:
yes
Positive control(s):
positive control groups received 40 mg/kg bw cyclophosphamide (CPA), dissolved in deionised water

Examinations

Details of tissue and slide preparation:
Femoral bone marrow was sampled from mice after sacrifice (24 hours after dosing) for all dose groups except for the high dose group (48 h after dosing). Bone marrow of the negative and positive control animals were sampled 24 h after administration. Slides were prepared from the bone marrow preparations, stained with May-Grünwald/Giemsa, and evaluated (without knowledge of the dose group) for the number of polychromatic erythrocytes (PCE) with micronuclei. At least 2000 PCEs per animal were analysed. In addition, the ratio between polychromatic and total erythrocytes per animal was determined. Five animals per sex and test group were evaluated as described above.

Results and discussion

Test results
Sex:
male/female
Genotoxicity:
negative
Toxicity:
yes
Remarks:
but only in the high dose group. toxic signs noted: palpebral closure and lethargy within the first hour after administration and lethargy for up to 6 hours after start of treatment.
Vehicle controls validity:
valid
Positive controls validity:
valid

Applicant's summary and conclusion

Conclusions:
HYDROXYETHYL-3,4-METHYLENEDIOXYANILINE HCL was not mutagenic in the in vivo micronucleus test using NMRI mice after a single intraperitoneal administration at doses up to the maximum tolerated dose of 250 mg/kg bw.
Executive summary:

HYDROXYETHYL-3,4-METHYLENEDIOXYANILINE HCL,dissolved in distilled water, was administered intraperitoneally to groups of 5 male and 5 female NMRI mice (supplied by HARLAN WINKELMANN, Germany; 7-12 weeks old at start of the treatment, mean bw 25.2±1.2 g (males) and 22.2±1.3 g (females)) at doses of 25, 125 and 250 mg/kg bw. For the high dose, two groups were treated to allow sampling after 24 and 48 hours. Single doses were administered in a total volume of 10 ml/kg bw to animals. Dose selection was based on findings in the pre-experiment in which doses of 250 and 1000 mg/kg bw were administered to three female and three male mice under the same treatment procedure. Negative control groups received distilled water and positive control groups received 40 mg/kg bw cyclophosphamide (CPA), dissolved in deionised water. Femoral bone marrow was sampled from mice after sacrifice (24 hours after dosing) for all dose groups except for the high dose group (48 h after dosing). Bone marrow of the negative and positive control animals were sampled 24 h after administration. Slides were prepared from the bone marrow preparations, stained with May-Grünwald/Giemsa, and evaluated (without knowledge of the dose group) for the number of polychromatic erythrocytes (PCE) with micronuclei. At least 2000 PCEs per animal were analysed. In addition, the ratio between polychromatic and total erythrocytes per animal was determined. Five animals per sex and test group were evaluated as described above. The animals were examined for acute toxic signs three times within the first 24 hours after treatment and the high dose group additionally 48 hours after administration. Stability and homogeneity data are not provided in the study. However, the test solution was prepared freshly prior to administration. In addition, a sufficient stability and solubility of HYDROXYETHYL-3,4-METHYLENEDIOXYANILINE HCL in water was analytically confirmed. In the pre-experiment, at 1000 mg/kg bw all animals (3 male and 3 female mice) died within 24 hours. At 250 mg/kg bw toxic signs noted were palpebral closure and lethargy within the first hour after administration and lethargy for up to 6 hours after start of treatment. No mortality occurred. Based on these findings, doses of 25, 100 and 250 mg/kg bw were chosen for the main study. In the main study, toxic signs like those described in the pre-experiment (250 mg/kg bw) were noted in all animals of the high dose group within the first hour after substance administration. The ratio between PCEs and total erythrocytes was not affected by the test item at any test concentration or sampling time as compared to the ratio observed in the vehicle control. However, the observed signs of systemic toxicity indicate that the test item was systemically distributed and bio-available. This assumption is further supported byin vivoandin vitrokinetic studies, in which a very good bioavailability after oral administration of aqueous formulations of HYDROXYETHYL-3,4-METHYLENE-DIOXYANILINE HCLwas demonstrated. There was no statistically significant or biologically relevant increase in the number of micronuclei per 2000 PCEs in the mice of any of the HYDROXYETHYL-3,4-METHYLENE-DIOXYANILINE HCL treated groups compared to the respective vehicle control groups. The positive control (CPA) induced a statistically significant increase in micronucleated PCEs and the values from the vehicle control groups were well within the range of historical control data of the performing laboratory. This demonstrates the validity and sensitivity of the used test system.

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