N-[3-(Triethoxysilyl)propyl]formamide

Skin sensitisation

Administrative data

Endpoint:

skin sensitisation: in vivo (LLNA)

Type of information:

experimental study

Adequacy of study:

key study

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: GLP guideline study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2012

Report date:

2012

Materials and methods

Test guideline

Test guideline 1

Qualifier:

according to guideline

Guideline:

OECD Guideline 429 (Skin Sensitisation: Local Lymph Node Assay)

Deviations:

no

Test guideline 2

Qualifier:

according to guideline

Guideline:

EU Method B.42 (Skin Sensitisation: Local Lymph Node Assay)

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Remarks:

Hess. Ministerium für Umwelt, Energie, Landwirtschaft und Verbraucherschutz, Mainzer Straße 80, D65189 Wiesbaden

Type of study:

mouse local lymph node assay (LLNA)

Test material

Test material information

Constituent 1

Reference substance name:

N-[3-(triethoxysilyl)propyl]formamide

EC Number:

700-340-6

Cas Number:

76524-94-2

Molecular formula:

C10H23NO4Si

IUPAC Name:

N-[3-(triethoxysilyl)propyl]formamide

Details on test material:

- Name of test material (as cited in study report): Y-15864
- Physical state: liquid
- Lot/batch No.: TER00010-68-31
- Expiration date of the lot/batch: September 12, 2012
- Stability under test conditions: Not indicated by the sponsor
- Internal Test Item Number: S 1279711

In vivo test system

Test animals

Species:

mouse

Strain:

other: CBA/CaCrl (pre-test), CBA/CaOlaHsd (main experiment)

Sex:

female

Details on test animals and environmental conditions:

TEST ANIMALS
- Source: Pre-test: Charles River UK, Manston Road, Margate, Kent CT9 4LT, United Kingdom; Main experiment: Harlan Laboratories B.V., Postbus 6174, 5960 AD Horst / The Netherlands
- Age at study initiation: Pre-test: 10 - 11 weeks (beginning of treatment); Main study: 9 – 10 weeks (beginning of treatment)
- Weight at study initiation: Mean: 21.8 ± 1.4; Range: 18.9 - 24.1
- Housing: group housing in Makrolon Type II / III cages with wire mesh top (EHRET GmbH, 79302 Emmendingen, Germany) and granulated soft wood bedding (Rettenmaier & Söhne GmbH + Co. KG, 73494 Rosenberg, Germany)
- Diet: pelleted standard diet, ad libitum (Harlan Laboratories B.V., 5960 AD Horst, Netherlands)
- Water: tap water, ad libitum (Gemeindewerke, 64380 Rossdorf, Germany)
- Acclimation period: At least 5 days prior to the start of dosing under test conditions

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 22 ± 2
- Humidity (%): 45 - 70
- Photoperiod (hrs dark / hrs light): 12/12

IN-LIFE DATES: From: To:

Study design: in vivo (LLNA)

Vehicle:

acetone/olive oil (4:1 v/v)

Concentration:

25%, 50% (w/v), and 100% (undiluted test item)

No. of animals per dose:

4 females (nulliparous and non-pregnant)

Details on study design:

RANGE FINDING TESTS:
- Compound solubility: A solubility experiment was performed according to the recommendations given by OECD 429. The highest test item concentration, which can be technically used, was 100% of the undiluted test item.
- Irritation: Pre-test with two animals was performed, highest non-irritating dose was 100%


MAIN STUDY
ANIMAL ASSIGNMENT AND TREATMENT
- Name of test method: Local Lymphnode Assay
- Criteria used to consider a positive response: Exposure to at least one concentration of the test item resulted in an incorporation of 3
HTdR at least 3-fold or greater than that recorded in control mice and a clear dose response.

TREATMENT PREPARATION AND ADMINISTRATION:
- The application volume, 25 µL/ear/day, was spread over the entire dorsal surface (8mm diameter) of each ear once daily for three consecutive days
- A further group of mice was treated with an equivalent volume of the relevant vehicle alone (control animals).
- 3 H-methyl thymidine (3HTdR) was purchased from Hartmann Analytic, 38124 Braunschweig, Germany (specific activity, 2 Ci/mmol; concentration, 1 mCi/mL).
- Five days after the first topical application (day 6) 250 µL of phosphate-buffered saline (PBS) containing 20.4 VCi of 3 HTdR (equivalent to 3 HTdR 81.4 VCi/mL) were injected into each test and control mouse via the tail vein.
- Approximately five hours after treatment with 3HTdR all mice were euthanised by intraperitoneal injection of Pentobarbital-Natrium (Release, WDT, 30827 Garbsen,Germany).
- 8 lymph nodes per group were pooled and level of 3HTdR incorporation was measured as the number of radioactive disintegrations per minute (DPM).

Positive control substance(s):

hexyl cinnamic aldehyde (CAS No 101-86-0)

Statistics:

The EC3 value was calculated according to the equation

EC3=(a-c) [(3-d)/(b-d)] + c

where EC3 is the estimated concentration of the test item required to produce a 3-fold increase in draining lymph node cell proliferative activity; (a, b) and (c, d) are respectively the coordinates of the two pair of data lying immediately above and below the S.I. value of 3 on the local lymph node assay dose response plot.

Results and discussion

In vivo (LLNA)

Results

Results 1

Parameter:

SI

Remarks on result:

other: 25%: 1.24 50%: 4.68 100%: 14.81

Results 2

Parameter:

other: disintegrations per minute (DPM)

Remarks on result:

other: DPM/lymph node: 0 % (negative control): 140.3 25%: 173.3 50%: 656.4 100%: 2076.8

Any other information on results incl. tables

Calculation of EC3 (EC3 = Estimated concentration for a S.I. of 3) value:

EC3 = (a-c) [(3-d)/(b-d)] + c = 37.8% (w/v)

a,b,c,d = Co-ordinates of the two pairs of data lying immediately above and below the S.I. value of 3 on the LLNA dose response plot

Applicant's summary and conclusion

Interpretation of results:

sensitising

Remarks:

Migrated information Criteria used for interpretation of results: EU

Conclusions:

CLP: Skin sensitiser Cat. 1B, H317
DSD: Sensitising, R43

Executive summary:

In a study according to OECD guideline 429 the test item Y-15864 was assessed for its possible skin sensitising potential by a local lymph node assay (LLNA). Concentrations of 25, 50% (w/v), and 100% (undiluted test item) were administered to 4 CBA mice per group. The animals did not show any signs of systemic toxicity or local skin irritation during the course of the study and no cases of mortality were observed. Stimulation Indices (S.I.) of 1.24, 4.68, and 14.81 were determined with the test item at concentrations of 25%, 50% (w/v), and 100% (undiluted test item) in acetone:olive oil (4+1 v/v), respectively. A clear dose response was observed. The test item Y-15864 was found to be a skin sensitiser and an EC3 value of 37.8% (w/v) was derived.