Registration Dossier

Toxicological information

Developmental toxicity / teratogenicity

Currently viewing:

Administrative data

Endpoint:
developmental toxicity
Type of information:
migrated information: read-across from supporting substance (structural analogue or surrogate)
Adequacy of study:
weight of evidence
Reliability:
1 (reliable without restriction)
Rationale for reliability incl. deficiencies:
other: very well documented publication

Data source

Reference
Reference Type:
publication
Title:
Unnamed
Year:
1987

Materials and methods

Test guideline
Qualifier:
no guideline followed
Principles of method if other than guideline:
Following literature references on teratology research
GLP compliance:
yes

Test material

Reference
Name:
Unnamed
Type:
Constituent
Details on test material:
Ethylenediamine dihydrochloride: Approximately 80 kg of EDA • 2HCI were received from Union Carbide Corp. (UCC South Charleston, WV). The sample was prepared from UCC's high-punty-grade ethylenediamine and ACS reagent grade concentrated aqueous HO obtained from Allied Chemical Corp. The synthesis was carried out at approximately 85°C in a 100-gallon glass-lined autoclave at a large-scale pilot plant in South Charleston, West Virginia. Following cooling and crystallization, EDA-2HC1 was recovered by centrifugation and washed with methanol to remove impurities. The yield of EDA • 2HC1 in this process was approximately 45%. The high-purity EDA used in the synthesis was 99.9% pure. On the basis of various analyses (elemental, water, infrared spectroscopy, emission spectrography, and high-pressure liquid chromatography (HPLC). the dihydrochloride was also
shown to be free from impurities.

Test animals

Species:
rat
Strain:
Fischer 344
Details on test animals and environmental conditions:
182 male and 192 female Fischer 344 rats, approximately 58 days of age, were received from Charles River Breeding Laboratories, Inc. (Kingston, NY).
Animals were housed in stainless-steel cages with food and water available ad libitum. Ground diet was supplied in 12-oz opal glass jars, and water was provided by an automatic dispensing system with demand-controlled valves in each cage.

Administration / exposure

Route of administration:
oral: feed
Details on exposure:
Ethylenediamine dihydrochloride (EDA-2HC1) was fed to groups of 20 (40 controls) timed-pregnant rats on Gestation Days 6 through 15 at 1.0,
0.25,0.05, or 0 g/kg/day. The day of discovery of a vaginal plug was considered gestation day 0.
On Gestation Day 21, the fetuses were delivered by cesarean section, and the standard endpoints for teratogenicity were evaluated.
Ethylenediamine dihydrochloride was added to the diet at concentrations based on established diet consumption data and an established growth curve for pregnant female Fischer 344 rats to produce dosage goals of 1.00, 0.25 and 0.05 g/kg/day. These dosages were selected based on the results of a 90-day study in which the same three dose levels had been used.
Frequency of treatment:
Ethylenediamine dihydrochloride (EDA-2HC1) was fed to groups of 20 (40 controls) timed-pregnant rats on Gestation Days 6 through 15 at 1.0,
0.25,0.05, or 0 g/kg/day. The day of discovery of a vaginal plug was considered gestation day 0.
On Gestation Day 21, the fetuses were delivered by cesarean section, and the standard endpoints for teratogenicity were evaluated.
Doses / concentrations
Remarks:
Doses / Concentrations:
100, 250, 50 and 0 mg/kg/day
Basis:
nominal in diet
No. of animals per sex per dose:
182 male and 192 female Fischer 344 rats, approximately 58 days of age, were received from Charles River Breeding Laboratories,
Inc. (Kingston, NY).

Examinations

Statistics:
The unit of statistical comparison was the pregnant female. Results of the quantitative continuous variables (e.g., maternal body weight gain and
liver weights) were compared using the following tests: Bartlett's test for homogeneity of variance (Sokal and Rohlf, 1981), analysis of variance and Duncan's multiple range test (Snedecor and Cochran, 1967). Whenever the F value for the analysis of variance was significant, the Duncan's multiple range test was used to denote which groups differed significantly from the control group. Where Bartlett's test indicated heterogeneous variances and for other nonparametric data, the Kruskal-Wallis test (Sokal and Rohlf, 1981) followed by individual Mann-Whitney U tests (Sokal and Rohlf, 1981) were used. Frequency data were compared by Fisher's exact test (Sokal and Rohlf, 1981). Fetal weights and lengths were compared using a nested analysis of variance (Sokal and Rohlf, 1981) and the method of Weil (1970).

Results and discussion

Results: maternal animals

Effect levels (maternal animals)

Dose descriptor:
NOAEL
Effect level:
ca. 250 mg/kg bw/day
Based on:
test mat.
Basis for effect level:
other: maternal toxicity

Results (fetuses)

Fetal abnormalities

Abnormalities:
not specified

Overall developmental toxicity

Developmental effects observed:
not specified

Applicant's summary and conclusion

Conclusions:
NOAEL= 250 mg/kg /day during gestation (effect: maternal toxicity)
Executive summary:

There was no evidence of teratogenicity in Fischer 344 rats from EDA-2HC1 ingestion during organogenesis.

The dose of 1000 mg/kg/day during gestation resulted in maternal toxicity, leading to reduced fetal weight, crown-rung length and increased litter resorption.

NOAEL = 250 mg/kg/day