N-(3-(trimethoxysilyl)propyl)ethylenediamine

Genetic toxicity: in vivo

Administrative data

Endpoint:

in vivo mammalian somatic cell study: cytogenicity / erythrocyte micronucleus

Type of information:

experimental study

Adequacy of study:

key study

Study period:

1988-03-15 to 1988-04-08

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

comparable to guideline study with acceptable restrictions

Remarks:

Only 1000 cells/animal were scored for micronuclei.

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

1988

Report date:

1988

Materials and methods

Test guideline

Test guideline 1

Qualifier:

equivalent or similar to guideline

Guideline:

OECD Guideline 474 (Mammalian Erythrocyte Micronucleus Test)

Deviations:

yes

Remarks:

number of micronucleated PCEs scored per 1000 cells, not 2000

Test guideline 2

Qualifier:

according to guideline

Guideline:

other: EPA Health Effect T G, EPA Report 560/6-83-001

GLP compliance:

yes

Type of assay:

micronucleus assay

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:

mouse

Strain:

Swiss Webster

Sex:

male/female

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: Charles River Laboratories, Portage, MI
- Age at study initiation: 5 weeks
- Weight at study initiation: male - 22.5 g - 28.0 g. female - 19.8 g - 21.7 g
- Assigned to test groups randomly: randomised separately by sex
- Fasting period before study: no
- Housing: 5 mice/sex/cage in shoe-box type plastic cages
- Diet (e.g. ad libitum): ad libitum
- Water (e.g. ad libitum): ad libitum


ENVIRONMENTAL CONDITIONS
- Temperature (°C): controlled but not specified
- Humidity (%): controlled but not specified
- Air changes (per hr): not known
- Photoperiod (hrs dark / hrs light): 12 hr light/dark cycle

Administration / exposure

Route of administration:

intraperitoneal

Vehicle:

- Vehicle(s)/solvent(s) used: corn oil
- Justification for choice of solvent/vehicle: incompatible with water thus corn oil was used
- Concentration of test material in vehicle: 200 mg/kg

Duration of treatment / exposure:

single i p dose

Frequency of treatment:

One treatment only

Post exposure period:

30, 48 and 72 hours

Doses / concentrations

Doses / concentrations 1

Dose / conc.:

87.5 mg/kg bw/day

Doses / concentrations 2

Dose / conc.:

175 mg/kg bw/day

Doses / concentrations 3

Dose / conc.:

280 mg/kg bw/day

No. of animals per sex per dose:

5

Control animals:

yes

Positive control(s):

Triethylenemelamine
- Justification for choice of positive control(s): known to demonstrate the sensitivity and responsiveness of the animals in the definitive test.
- Route of administration: i p
- Doses / concentrations: 0.3 mg/kg bw

Examinations

Tissues and cell types examined:

Blood was collected by nicking the tail of each animal with a scalpel and slides prepared for each animal per sampling time. Polychromatic erythrocytes (PCE's) were examined.

Details of tissue and slide preparation:

CRITERIA FOR DOSE SELECTION: Determination of the PCE/NCE ratio for the groups of animals with partial mortality was used to evaluate the possibility of bone marrow cytotoxicity from the test chemical. Three dose levels of approximately 80%, 50% and 25% of the LD50 value were evaluated for effects upon the incidence of micronuclei.

TREATMENT AND SAMPLING TIMES (in addition to information in specific fields): i.p. injection followed by sampling times of 30, 48 and 72 hours

DETAILS OF SLIDE PREPARATION: Slides were stained with Gurr's R-66 Giemsa diluted in phosphate buffer. Slides were coded by animal number only and read blindly.

METHOD OF ANALYSIS: A minimum of 1000 PCE's were examined microscopically for each animal per sample time. The PCE/NCE ratio for approximately 1000 total cells was calculated and recorded. The number of micronucleated PCE/1000 NCE was recorded.

Evaluation criteria:

A test result is considered to be negative if no statistically significant or dose related increases are apparent between the vehicle control and groups of animals treated with Organofunctional Silane A-1120.

Statistics:

Fisher's Exact Test (Sokal and Rohlf, 1981)

Results and discussion

Test results

Key result

Sex:

male/female

Genotoxicity:

negative

Toxicity:

yes

Remarks:

LD50 354 mg/kg bw and above. PCE/NCE ratio was reduced at highest concentration, 48 h exposure and at all doses, 72 h exposure.

Vehicle controls validity:

valid

Negative controls validity:

not applicable

Positive controls validity:

valid

Additional information on results:

RESULTS OF RANGE-FINDING STUDY
- Dose range: 125 mg/kg bw - 2000 mg/kg b
- Solubility: Incompatible with water thus corn oil was used
- Clinical signs of toxicity in test animals: All mice dosed at 1000 mg/kg bw and 2000 mg/kg bw died. 500 mg/kg bw was lethal to 4 out of 5 females and all the male mice. One female tested at 250 mg/kg bw died.
- Evidence of cytotoxicity in tissue analyzed: a decrease in the PCE/NCE ratio to 80% of the control value was observed at the 48 hour treatment interval. At 72 hours the PCE/NCE ratios had increased.
- Harvest times: 48 hours


RESULTS OF DEFINITIVE STUDY

- Induction of micronuclei (for Micronucleus assay): negative.
- Ratio of PCE/NCE (for Micronucleus assay): PCE/NCE ratio was slightly decreased at 72 hour treatment interval.
- Appropriateness of dose levels and route: Both dose levels and route were appropriate.
- Statistical evaluation: Analysis of variance indicated no sex-related differences in the incidence of micronuclei. No statistically significant (p ≤ 0.01) or treatment related increases in the numbers of micronuclei were observed at any dose or treatment interval.

Any other information on results incl. tables

Table 3: Summary of micronucleus results

	30 hours				48 hours				72 hours
Treatment groups mg/kg bw	Number of PCE’s with micronuclei per 1000 PCE’s		Mean PCE’s/1000 NCE (SD)		Number of PCE’s with micronuclei per 1000 PCE’s		Mean PCE’s/1000 NCE (SD)		Number of PCE’s with micronuclei per 1000 PCE’s		Mean PCE’s/1000 NCE (SD)
	Male	Female	Group mean	SD	Male	Female	Group mean	SD	Male	Female	Group mean	SD
Vehicle control	4.0 (2.00)	1.6 (0.89)	33.7	5.52	2.4 (2.70)	3.6 (1.14)	36.4	4.24	3.8 (2.05)	3.8 (2.68)	42.9	3.25
87.5	5.0 (2.55)	3.6 (1.52)	31.8	6.79	3.0 (1.73)	2.2 (0.84)	36.0	0.28	6.4 (2.19)	2.8 (1.64)	33.9	2.12
175	2.6 (1.52)	4.0 (1.22)	34.9	8.06	3.2 (1.10)	3.8 (1.64)	37.2	7.92	2.3 (0.96)	5.2 (3.96)	35.5	6.68
280	3.4 (2.19)	3.6 (2.19)	35.4	4.81	3.4 (3.29)	3.0 (1.22)	30.4	3.39	3.8 (1.92)	1.2 (0.84)	27.9	1.27
Positive control	36.2 (16.84)	28.6 (10.31)	27.4	9.05	Not evaluated		Not evaluated		Not evaluated		Not evaluated

Table 4 Summary of micronucleus frequency and statistical differences from controls (Fisher's exact test, one-tailed)

Treatment/dose mg/kg bw	No. PCE observed	PCE with micronuclei	Statistical significance
	30 hour sample
Vehicle control	10 000	28	NS
87.5	10 000	43	0.05>p>0.01*
175	10 000	33	NS
280	10 000	35	NS
Positive control	10 000	324	p<0.001
	48 hour sample
Vehicle control	10 000	30	NS
87.5	10 000	26	NS
175	10 000	35	NS
280	10 000	32	NS
	72 hour sample
Vehicle control	10 000	38	NS
87.5	10 000	46	NS
175	10 000	35	NS
280	10 000	25	NS

Results from sexes are combined as no sex-related differences were shown.

* not considered of biological significance

Applicant's summary and conclusion

Conclusions:

N-(3-(trimethoxysilyl)propyl)ethylenediamine has been tested in a reliable study according to EPA Health Effect T G, Report 560/6-83-001, which is similar to OECD 474, and under GLP conditions. No treatment related increases in numbers of micronuclei in PCE's of Swiss-Webster mice were observed. Relatively high dose levels of the test compound were tested up to 80% of the LD50 with no indication of significant induction of micronuclei. The PCE/NCE ratio was reduced at the highest concentration, 48 h exposure and at all doses, 72 h exposure, indicating exposure of the target tissue to the test substance. The test compound is considered to be negative for the induction of micronuclei under the conditions of this test.