Dimethyloctadecyl[3-(trimethoxysilyl)propyl]ammonium chloride

Toxicity to reproduction

Administrative data

Endpoint:

one-generation reproductive toxicity

Remarks:

based on test type (migrated information)

Type of information:

experimental study

Adequacy of study:

key study

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: Data is from peer reviewed journal

Data source

Reference

Reference Type:

publication

Title:

A Developmental Toxicity Study in Rats.

Author:

SIDDIQUI et.al

Year:

1993

Bibliographic source:

FUNDAMENTAL AND APPLIED TOXICOLOGY (1993)

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

other: as mentioned below

Principles of method if other than guideline:

Developmental Toxicity Study of Quaternary Silsesquioxane in rats

GLP compliance:

not specified

Limit test:

no

Test material

Test material information

Constituent 1

Reference substance name:

Dimethyloctadecyl[3-(trimethoxysilyl)propyl]ammonium chloride

EC Number:

248-595-8

EC Name:

Dimethyloctadecyl[3-(trimethoxysilyl)propyl]ammonium chloride

Cas Number:

27668-52-6

Molecular formula:

C26H58NO3Si.Cl

IUPAC Name:

dimethyl(octadecyl)[3-(trimethoxysilyl)propyl]azanium chloride

Test material form:

other: Liquid

Details on test material:

- Name of test material (as cited in study report):Quaternary Silsesquioxane
- Molecular formula :C26H58NO3Si.Cl
- Molecular weight :496.287 g/mole
- Substance type:Organic
- Physical state:Liquid

Test animals

Species:

rat

Strain:

Sprague-Dawley

Sex:

female

Details on test animals or test system and environmental conditions:

Details on test animals and env. conditions
TEST ANIMALS
- Source: Charles River Breeding Laboratories, Inc. (Portage, MI).
- Age at study initiation: 13 weeks
- Weight at study initiation: 206 to 275 g at gestation day 0
- Fasting period before study: No data available
- Housing: Animal were housed individually, except during mating, in suspended stainless steel wire mesh cages from receipt until sacrifice.
- Use of restrainers for preventing ingestion (if dermal): No data available
- Diet (e.g. ad libitum): basal laboratory diet of Certified Rodent Chow 5002 (Ralston Purina Co., St. Louis, MO), ad libitum
- Water (e.g. ad libitum): tap water, ad libitum
- Acclimation period: 12 days

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 17 -20°C
- Humidity (%):Relative humidity: 30-70%
- Air changes (per hr): No data available
- Photoperiod (hrs dark / hrs light): 12 hrs

IN-LIFE DATES: From: To: No data available

Administration / exposure

Route of administration:

oral: gavage

Type of inhalation exposure (if applicable):

not specified

Vehicle:

corn oil

Details on exposure:

Details on oral exposure
PREPARATION OF DOSING SOLUTIONS: Quat-Silsesquioxane was suspended fresh daily in corn oil

DIET PREPARATION
- Rate of preparation of diet (frequency): No data available
- Mixing appropriate amounts with (Type of food): No data available
- Storage temperature of food: No data available

VEHICLE
- Justification for use and choice of vehicle (if other than water): corn oil.
- Concentration in vehicle: 0, 100, 300, and 1000 mg/kg/day
- Amount of vehicle (if gavage): 10 ml/kg.
- Lot/batch no. (if required): No data available
- Purity: No data available

Details on mating procedure:

- M/F ratio per cage:1:1
- Length of cohabitation:No data available
- Proof of pregnancy: [vaginal plug / sperm in vaginal smear] referred to as [day 0 / day 1] of pregnancy:Copulatory plug referred to as 0 of pregnancy
- After ... days of unsuccessful pairing replacement of first male by another male with proven fertility.:No data available
- Further matings after two unsuccessful attempts: No data available
- After successful mating each pregnant female was caged (how):stainless steel wire mesh cages: Individually
- Any other deviations from standard protocol:No data available

Analytical verification of doses or concentrations:

not specified

Duration of treatment / exposure:

10 days

Frequency of treatment:

Daily from gestation days 6 to 15

Details on study schedule:

No data available

Doses / concentrations

Remarks:

Doses / Concentrations:
0, 100, 300 and 1000 mg/kg/day
Basis:
other: Dosage levels were selected from the results obtained in a range-finding developmental toxicity study

No. of animals per sex per dose:

25 rats per doses

Control animals:

yes, concurrent vehicle

Details on study design:

- Dose selection rationale: Dosage levels were selected from the results obtained in a range-finding developmental toxicity study. In that study neither maternalnor developmental toxicity was seen at dosage levels of up to 1000 mg/kg/day.
- Rationale for animal assignment (if not random): Mated females were assigned consecutively, in the order the mating was detected
- Rationale for selecting satellite groups: No data available
- Post-exposure recovery period in satellite groups:No data available
- Section schedule rationale (if not random):No data available

Positive control:

No data available

Examinations

Parental animals: Observations and examinations:

CAGE SIDE OBSERVATIONS: Yes
- Time schedule: twice daily
- Cage side observations checked in table [No.?] were included. For changes in appearance, behavior and mortality.

DETAILED CLINICAL OBSERVATIONS: Yes
- Time schedule: twice daily

BODY WEIGHT: Yes
- Time schedule for examinations: daily on Gestation Days 0,6,9, 12, 16, and 20.

FOOD CONSUMPTION AND COMPOUND INTAKE (if feeding study):Yes
- Food consumption for each animal determined and mean daily diet consumption calculated as g food/kg body weight/day: Yes
- Compound intake calculated as time weighted averages from the consumption and body weight gain data: No data available

FOOD EFFICIENCY:
- Body weight gain in kg/food consumption in kg per unit time X 100 calculated as time-weighted averages from the consumption and body weight gain data: No data available

WATER CONSUMPTION AND COMPOUND INTAKE (if drinking water study): No data available
- Time schedule for examinations: No data available

other:
organ weight: liver and gravid uterine weight was recorded

Oestrous cyclicity (parental animals):

Nongravid Uteri were examined for Corpora lutea, Total implantation and Postimplantation loss.

Sperm parameters (parental animals):

No data available

Litter observations:

viable fetuses, crown-rump length, fetal body weight and sex ratio were examined.

Postmortem examinations (parental animals):

SACRIFICE
- Male animals: No data available
- Maternal animals: Yes, gross pathology were examined.

Postmortem examinations (offspring):

Postmortem examinations (offspring)
SACRIFICE: Yes

GROSS NECROPSY: Yes

HISTOPATHOLOGY: Yes
One-half of the fetuses were examined for soft tissue and remaining half for subsequent skeletal examination.

Statistics:

1)Mean maternal body weights and liver weights, maternal feed consumption, numbers of corpora lutea, total implantations, live fetuses, gravid uterine weight, and mean fetal body weights were compared by one-way analysis of variance (ANOVA), Bartlett's test for homogeneity of variance, and the appropriate test for equal and unequal variance (Steel and Torrie, 1960) using Dunnett's multiple comparison.
2) The proportions of resorbed and dead fetuses and postimplantation losses were compared by the Mann-Whitney t/test.
3) Male to female fetal sex ratios and the proportions of litters with malformations and developmental variations were compared using the x1 test criterion with Yate's correction for 2 X 2 contingency tables and/or
Fisher's exact probability test.

Reproductive indices:

Fertility and gestation were examined.

Offspring viability indices:

yes, viable fetuses were examined.

Results and discussion

Results: P0 (first parental generation)

General toxicity (P0)

Clinical signs:

no effects observed

Body weight and weight changes:

no effects observed

Food consumption and compound intake (if feeding study):

no effects observed

Organ weight findings including organ / body weight ratios:

effects observed, treatment-related

Histopathological findings: non-neoplastic:

not specified

Other effects:

not specified

Description (incidence and severity):

Test substance intake: No data available

Reproductive function / performance (P0)

Reproductive function: oestrous cycle:

no effects observed

Reproductive function: sperm measures:

not specified

Reproductive performance:

no effects observed

Details on results (P0)

Mortality – No effect on survival of treated female rats were observed as compared to contorl.

Clinical signs- No clinical signs or behavioral changes were observed in treated female rats as compared to control.

Body weights – No body weight changes were observed in treated femlae rats as compared to contorl.

Feed consumption - No feed consumption changes were observed in treated female rats as compared to control.

Reproductive funtion: estrous cycle:
No adverse effects on mean number of corpora lutea, number of live fetuses per litter, litter size, mean fetal body weight, or mean crown-rump length.

Reproductive performance:
Ratio of male and female pups at the 1000 mg/ kg/day dose level was significantly different from the control group but was not considered treatment related.

Organ weight - Slight but significant increase in relative liver weight of treated female rats was observed as compared to control.

Effect levels (P0)

Dose descriptor:

NOAEL

Effect level:

300 mg/kg bw/day (nominal)

Based on:

test mat.

Sex:

female

Basis for effect level:

other: No effect on survival, Clinical signs, Body weight, Organ weight and reproductive performance

Results: F1 generation

General toxicity (F1)

Clinical signs:

not specified

Mortality / viability:

no mortality observed

Body weight and weight changes:

no effects observed

Sexual maturation:

not specified

Organ weight findings including organ / body weight ratios:

not specified

Gross pathological findings:

no effects observed

Histopathological findings:

no effects observed

Details on results (F1)

Viability: No effect on viability of fetuses were observed as compated to control.

Body weight: No significant effect were observed on fetal body weight as compared to control.

Gross pathology :No significant external malformations were observed in treated fetuses as compared to control.

Histopathology :
When treated with 1000 mg/kg bw, One fetus with bent limb bones, Two fetuses from different mothers with microphthalmia and two other fetuses with omphalocele were observed in treated fetuses as compared to control.

When treated with 300 mg/kg bw, single fetus with multiple malformations were observed in treated fetuses as compared to control.
The incidence of developmental variations in the treated litters was not significantly increased over the control incidence. They occurred in low frequency and were distributed randomly across the Quat-Silsesquioxane treated and control groups.

Effect levels (F1)

Dose descriptor:

NOAEL

Generation:

F1

Effect level:

1 000 mg/kg bw/day

Based on:

test mat.

Sex:

male/female

Basis for effect level:

other: No effect on Viability , body weight, gross pathology and histopathology

Overall reproductive toxicity

Reproductive effects observed:

not specified

Any other information on results incl. tables

TABLE 1

Summary of Maternal Body Weight Gain, Food Consumption, and Liver Weights

		Dose levels (mg/kg/day)
Gestation day		0	100	300	1000
		Mean body weight change (g)
0-6		26 ± 7^a	25 ±7	27 ±7	29 ±8
6-9		3 ± 8	3 ± 8	7±7	6 ± 8
9-12		16 ± 10	19 ±6	15 ± 4	15 ± 9
12-16		27 + 7	26 ± 12	22 ± 8	22 ± 11
16-20		59 ± 11	61 ± 17	62 ± 13	60 ± 15
0-20		131 ± 19	133 ±25	132 ± 19	132 ±25
0-20 adjusted^b		61 + 13	62 ± 14	62+13	66 ± 13
Mean food consumption (g/dam/day)
0-6	21.5 + 2		21.5 ±2	22.3 ±2	22.0 ± 4
6-9	17.8 ± 4		15.2 ±3*	17.9 ± 3	19.9 ± 8
9-12	17.9 ± 2		17.9 ± 2	19.9 ±3*	21.2 ±8
12-16	19.8 ± 2		21.1 ±5	20.4 ± 3	20.2 ±4
16-20	27.3 ± 2		27.4 ±3	26.2 ±6	28.0 ±2
0-20	21.3+1		21.2 ± 2	21.7 ± 2	22.5 ± 3
Mean maternal liver weight(20 days of gestation)
Absolute (g)	15.4 + 2.9		15.3 ±2.9	16.1 ±2.6	16.5 ±2.5
Relative (%)	4.4 ± 0.4		4.4 ± 0.3	4.5 ±0.3	4.6 ± 0.2*

^aMean ± SD.

^bDam body weight minus the uterus and its contents.

* Significantly different from controls; ANOVA, Welch Test, P < 0.05            

          

TABLE 2

Summary of Observations at Time of Cesarean Sections

	Dose levels (mg/kg/day)
	0	100	300	1000
Animals examined at cesarean sections	25	25	25	25
Nongravid	7	7	5	4
Gravid	18	18	20	21
Dams with resorptions only	0	0	0	0
Dams with viable fetuses	18	18	20	21
Viable fetuses/dam^a	13.3 ±2.7	13.3 ± 3.3	13.2 ± 4.2	12.4 ± 4.0
Postimplantation loss/dam^a	1.1 ±0.8	0.6 ± 0.61	1 5 ± 2.31	0.8 + 0.8
Total implantation/dam^a	14.4 ±2.5	13.9 ± 3.5	14.7 ± 3.4	13.2 ± 4.4
Corpora lutea/dam^a	17.8 ±3.3	15.8 ± 2.6	17.7 ± 2.9	16.2 ± 3.2
Mean crown-rump length (cm)	3.5 ±0.1	3.5 ± 0.2	3.5 ± 0 1	3.5 ± 0 1
Group mean uterine weights (g)	70.1 ±14.1	71.3 ±17.7	70.3 ±21.2	66.5 ± 18.2
Group mean preimplantation loss (%)	18.8	12.0	17.2	18.2
Group mean postimplantation loss (%)	7.7	4.4	9.9	6.1
Mean fetal body weight (g)	3.4 ±0.2	3.5 ± 0.5	3.4 ± 0.2	3.4 + 0.3
Fetal sex ratio—m:f (%)	44:56	49:51	50:50	55:45*

^aMean ± SD.

* Significantly different; x2. P * 0.05.

TABLE 3

Summary of the Incidence of Fetal Malformations*

	Dose levels (mg/kg/day)
	No. examined
Litters	18	18	20	21
Fetuses externally	240	238	263	260
Fetuses viscerally	119	118	132	129
Fetuses skeletally	121	121	132	132
	No.of fetuses (No. Of litters) affected
Malformations observed
Anophthalmia	1 (1)
Microphthalmia				2(2)
Gastroschisis			1(1)
Omphalocele				2(2)
Tail agenesis			1(1)
Tarsal flexure			1(1)
Edema			1(1)
Malformed skull bones			1(1)
Bent clavicle			1(1)
Bent scapula			1(1)
Amelia			1(1)
Micromelia			1(1)
Bent limb bones	1(1)			1(1)
Vertebral agenesis			1(1)
Pelvic malformation			1(1)
Total fetuses (litters) with malformations	2(2)	0(0)	1(1)	5(4)

* No statistical significance was observed.

TABLE 4

Summary of the Incidence of Fetal Variations*

	Summary of the Incidence of Fetal Variations*
	Dose levels (mg/kg/day)
	0	100	300	1000
	No. examined
Litters	18	18	20	21
Fetuses externally	240	238	263	260
Fetuses viscerally	119	118	132	129
Fetuses skeletally	121	121	132	132
	No.of fetuses (No. Of litters) affected
Developmental variations observed
Renal papillae not developed		1(1)	1(1)
Distended ureter		1(1)	1(1)
Skull reduced in ossification	2(1)	3(2)	2(2)
Hyoid unossified	1(1)		1(1)	1(1)
25 presacral vertebrae			1(1)	2(2)
Greater than 13 pairs of full ribs			2(2)
14th rudimentary rib(s)	6(3)	7(4)	12(5)	6(5)
Bent ribs		1(1)		2(1)
7th cervical rib	3(3)		2(2)
Vertebrae reduced in ossification	1(1)		1(1)
Misaligned sternebra(e)	8(6)	6(5)	8(6)	4(3)
Sternebra 5 and/or 6 unossified	3(5)	7(6)	4(4)	8(6)
Other sternebra(e) unossified	1(1)		1(1)	1(1)
Ischia reduced in ossification	1(1)			2(1)
Total fetuses (litters) with developmental variations	22(12)	24(11)	30(14)	22(12)

* No statistical significance was observed.

Applicant's summary and conclusion

Conclusions:

NOAEL was considered to be 300 mg/kg bw for P generation and 1000 mg/kg for F1 generation when Sprague-Dawleyd female rats were treated with Quat-Silsesquioxane orally by gavage from day 6 to 15 of gestation.

Executive summary:

In a developmental toxicity study, Sprague-Dawley female rats were treated with Quat-Silsesquioxane in the concentration of 0, 100, 300, or 1000 mg/kg/day orally by gavage in corn oil.No maternal mortality and clinical signs or behavioral changes were observed in treated female rats as compared to control. No effect on body weight and feed consumption changes were observed in treated female rats as compared to control. Similarly, no effect on reproductive parameters such as number of corpora lutea, number of live fetuses per litter, litter size, mean fetal body weight, or mean crown-rump length was observed in treated rats. Ratio of male and female pups at the 1000 mg/ kg/day dose level was significantly different from the control group but was not considered treatment related. Slight but significant increase in relative liver weight of treated female rats was observed as compared to control. In addition, No effect on viability, fetal body weight and external malformations were observed in treated fetuses as compared to control. One fetus with bent limb bones, two fetuses from different mothers with microphthalmia and two other fetuses with omphalocele were observed at 1000 mg/kg/day and single fetus with multiple malformations were observed at 300 mg/kg/day in treated fetuses as compared to control. The incidence of developmental variations in the treated litters was not significantly increased over the control incidence. They occurred in low frequency and were distributed randomly across the Quat-Silsesquioxane treated and control groups. Therefore,NOAEL was considered to be 300 mg/kg bw for P generation and 1000 mg/kg for F1 generation when Sprague-Dawley female rats were treated with Quat-Silsesquioxane orally by gavage from day 6 to 15 of gestation.