N-[3-(trimethoxysilyl)propyl]butylamine

Developmental toxicity / teratogenicity

Administrative data

Endpoint:

developmental toxicity

Type of information:

experimental study

Adequacy of study:

key study

Study period:

24 September 2001 to 06 September 2002

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

comparable to guideline study

Cross-reference

Reason / purpose for cross-reference:

reference to same study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2002

Report date:

2002

Materials and methods

Test guideline

Test guideline 1

Qualifier:

equivalent or similar to guideline

Guideline:

other: OECD 422 (Combined Repeated Dose Toxicity Study with the Reproduction / Developmental Toxicity Screening Test) (1996)

Deviations:

yes

Remarks:

(additionally 10 females per dose group were added to the study to determine the repeated dose toxicity to females)

Test guideline 2

Qualifier:

equivalent or similar to guideline

Guideline:

other: USEPA Health Effects test guideline OPPTS 870.3650 (2000)

GLP compliance:

yes

Limit test:

no

Test material

Test material information

Constituent 1

Reference substance name:

N-(3-(trimethoxysilyl)propyl)ethylenediamine

EC Number:

217-164-6

EC Name:

N-(3-(trimethoxysilyl)propyl)ethylenediamine

Cas Number:

1760-24-3

Molecular formula:

C8H22N2O3Si

IUPAC Name:

N-(3-(trimethoxysilyl)propyl)ethylenediamine

Test animals

Species:

rat

Strain:

Sprague-Dawley

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Strain: Crl:CD (SD)IGBS VAF/Plus
- Source: Charles River Laboratories, Inc. , Portage, MI
- Age at study initiation: 8 weeks
- Weight at study initiation: males 253-301 g, females 181-229 g
- Fasting period before study: None
- Housing: individually in suspended wire-mesh cages elevated over Bed-O'Cobs bedding; during cohabitation the females were pared 1 to 1 with a male in a suspended wire-mesh cage; pregnant females were moved into shoebox cages containing Enviro-dri and Bed-O'Cobs combination bedding (no later than three days prior to their expected delivery date until remainder of the study)
- Diet: PMI Certified Rodent Chow #5002 (PMI Nutritional International, St. Luis, MO), ad libitum
- Watert: Municipal water, further purified by reverse osmosis, ad libitum
- Acclimation period: 5 days

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 19-25
- Humidity (%): 30-70
- Air changes (per hr): 10-15
- Photoperiod (hrs dark / hrs light): 12/12

IN-LIFE DATES: From: 01 October 2001 to: 11 April 2002

Administration / exposure

Route of administration:

oral: gavage

Vehicle:

corn oil

Details on exposure:

PREPARATION OF DOSING SOLUTIONS:
The dosing formulations were prepared daily by adding an appropriate amount of test substance to a measured amount of vehicle (dried and de-acidified) under nitrogen atmosphere. The dosing formulations were maintained under nitrogen atmosphere until the time of dosing.

VEHICLE
- Justification for use and choice of vehicle: Corn oil was dried and de-acidified to remove residual water before use as test substance hydrolyses in contact with moisture.
- Lot/batch no.: 070K0127
- Purity: 100%

Analytical verification of doses or concentrations:

yes

Details on analytical verification of doses or concentrations:

Concentration, homogeneity and stability of the test substance in the vehicle were verified by gas chromatopgraphy with a flame ionisation detection (FID). Concentration verification was conducted on a weekly basis.

Details on mating procedure:

- Impregnation procedure: cohoused
- If cohoused:
- M/F ratio per cage: 1:1
- Length of cohabitation: Until evidence of copulation occurred or up to 2 weeks
- Proof of pregnancy: vaginal plug or sperm in vaginal smear referred to as day 0 of pregnancy
- M/F ratio per cage: 1:1 ratio
- Length of cohabitation: Until evidence of copulation occurred or up to 2 weeks
- Proof of pregnancy:vaginal plug or sperm in vaginal smear referred to as day 0 of pregnancy
- Further matings after unsuccessful attempt: no (non-pregnant females were sacrificed 21 days post mating)
- After successful mating each pregnant female was caged in shoebox cages containing Enviro-dri and Bed-O'Cobs combination bedding (no later than three days prior to their expected delivery date until remainder of the study)

Duration of treatment / exposure:

Males: 28 days (beginning 2 weeks prior to mating)
Toxicity phase female: 29 days (beginning 2 week prior to mating)
Reproductive phase females: 39-44 days (2 weeks prior to mating, throughout mating and pregnancy until day 3 postpartum)

Frequency of treatment:

Daily (seven days/week)

Duration of test:

Up to 44 days

Doses / concentrations

Doses / concentrations 1

Dose / conc.:

25 mg/kg bw/day (actual dose received)

Doses / concentrations 2

Dose / conc.:

125 mg/kg bw/day (actual dose received)

Doses / concentrations 3

Dose / conc.:

500 mg/kg bw/day (actual dose received)

No. of animals per sex per dose:

10 males and 20 females (10 females in reproductive group and 10 females in toxicity group)

Control animals:

yes, concurrent vehicle

Details on study design:

- Dose selection rationale: Based on the results of a 7 day oral range-finding study

Examinations

Maternal examinations:

CAGE SIDE OBSERVATIONS: Yes
- Time schedule: Twice daily for morbidity, moribundity and mortality. General clinical observations were made at least once per day, approximately one hour after dosing.

DETAILED CLINICAL OBSERVATIONS: Yes
- Time schedule: Once before the first dosing and weekly thereafter.

BODY WEIGHT: Yes
- Time schedule for examinations: Individual body weights were recorded weekly beginning approximately one week prior to test substance administration, on the first day of dosing and just prior to scheduled necropsy.

FOOD CONSUMPTION:
Individual food consumption was recorded weekly for female animals in the toxicity group for four weeks. Individual food consumption for the male animals and the reproductive group females were recorded during the first two weeks of treatment. Food consumption was not measured during the cohabitation period. Food consumption was measured for the reproductive group females throughout gestation until terminal sacrifice.

HAEMATOLOGY: Yes
- Time schedule for collection of blood: On the day of scheduled sacrifice
- Anaesthetic used for blood collection: Yes, ketamine HCl/Xylazine
- Animals fasted: Yes, overnight
- How many animals: All male and toxicity group females
- Parameters checked in table 1 were examined.

CLINICAL CHEMISTRY: Yes
- Time schedule for collection of blood: On the day of scheduled sacrifice
- Animals fasted: Yes
- How many animals: All male and toxicity group females
- Parameters checked in table 1 were examined.

FUNCTIONAL OBSERVATIONAL BATTERY (FOB): Yes
- Time schedule for examinations: Prior to the start of dosing and during the fourth week of the treatment. The assessments were conducted following the daily dose administration.
- Dose groups that were examined: All male and toxicity group females.
- Battery of functions tested: cageside observations, hand-held observations, open field observations, categorical observations, measurements/counts, motor activity.

Ovaries and uterine content:

The ovaries and uterine content was examined after termination: Yes
Examinations included:
- Gravid uterus weight: No
- Number of corpora lutea: Yes
- Number of implantations: Yes
- Number of early resorptions: No
- Number of late resorptions: No

Fetal examinations:

SACRIFICE
- Postpartum day 4

GROSS NECROPSY
- Gross necropsy consisted of external and internal examinations including the cervical, thoracic, and abdominal viscera.

HISTOPATHOLOGY / ORGAN WEIGHTS
Not conducted.

Statistics:

All data analysis was carried out using SAS. In all comparisons, the family wise error rate was held at 5% (alpha=0.05). Prior to this analysis, an exploratory analysis was carried out on all variables tested. Bartlett's test was used to check for heterogeneity of variances and a Kolmogorov-smirnov test was used to test normality of the data. Parametric data was then tested using one-way Analysis of Variance (ANOVA) followed by Dunnett's Test (if significant). Non-parametric data were tested by Kruskal Wallis Test followed by Wilcoxon (if significant). For variables that had multiple measurements across time Repeated Measurement ANOVA was used to analyse the data. Categorical data were tested for equal proportions using the Fisher's Exact Test.

Statistically significant probabilities are reported at either the p≤0.05 or p≤0.01 levels.

Indices:

Viability and fertility

Results and discussion

Results: maternal animals

Maternal developmental toxicity

Details on maternal toxic effects:

Maternal toxic effects:no effects

Details on maternal toxic effects:
No significant adverse systemic effects in maternal animals were observed throughout the study period.

Effect levels (maternal animals)

1

Dose descriptor:

NOAEL

Effect level:

>= 500 mg/kg bw/day (actual dose received)

Based on:

test mat.

Basis for effect level:

other: maternal toxicity

2

Dose descriptor:

NOAEL

Effect level:

>= 500 mg/kg bw/day (actual dose received)

Based on:

test mat.

Basis for effect level:

other: developmental toxicity

Results (fetuses)

Details on embryotoxic / teratogenic effects:

Embryotoxic / teratogenic effects:no effects

Details on embryotoxic / teratogenic effects:
No abnormal behaviour or effects, including teratogenic, were observed in the offspring throught the study period.

Effect levels (fetuses)

Dose descriptor:

NOAEL

Effect level:

>= 500 mg/kg bw/day (actual dose received)

Based on:

test mat.

Sex:

male/female

Basis for effect level:

other: no effects observed

Fetal abnormalities

Abnormalities:

not specified

Overall developmental toxicity

Developmental effects observed:

not specified

Applicant's summary and conclusion

Conclusions:

In an oral gavage study conducted similar to OECD 422 and to GLP the NOAEL for N-(3-(trimethoxysilyl)propyl)ethylenediamine relating to repeated dose (systemic) effects and to developmental toxicity was at least 500 mg/kg bw/day, as no significant adverse effects were observed up to the highest dose of 500 mg/kg bw/day tested in rats.