3,5-DIMETHOXY-4-(1-METHYLPROPOXY)BENZALDEHYDE

Skin sensitisation

Administrative data

Endpoint:

skin sensitisation: in vivo (LLNA)

Type of information:

experimental study

Adequacy of study:

key study

Study period:

26 January 2004 to 16 February 2004

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: Guideline study under GLP

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2004

Report date:

2004

Materials and methods

Test guideline

Test guideline 1

Qualifier:

according to guideline

Guideline:

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

Test guideline 2

Qualifier:

according to guideline

Guideline:

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

Test guideline 3

Qualifier:

according to guideline

Guideline:

EPA OPPTS 870.2600 (Skin Sensitisation)

GLP compliance:

yes

Type of study:

mouse local lymph node assay (LLNA)

Test material

Test material information

Constituent 1

Reference substance name:

4-(butan-2-yloxy)-3,5-dimethoxybenzaldehyde

EC Number:

607-081-7

Cas Number:

224586-49-6

Molecular formula:

C13H18O4

IUPAC Name:

4-(butan-2-yloxy)-3,5-dimethoxybenzaldehyde

Test material form:

other: liquid

Details on test material:

- Name of test material (as cited in study report): v175023
- Physical state: brown liquid
- Analytical purity: 99.05%
- Lot/batch No.: v175023/P8B
- Expiration date of the lot/batch: 15 Dec 2004
- Storage condition of test material: at room temperature protected from light

In vivo test system

Test animals

Species:

mouse

Strain:

CBA

Sex:

female

Details on test animals and environmental conditions:

TEST ANIMALS
- Source: Charles River France, L'Arbresle Cedex, France
- Age at study initiation: ca 11 weeks
- Weight at study initiation: 17-26 g
- Housing: individually in Macrolon cages (MI)
- Diet: pelleted laboratory animal diet ad libitum (Altromin (VRF1), Lage, Germany)
- Water: tap water ad libitum
- Acclimation period:> 5 days

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 17.4-21.6°C
- Humidity (%): 26-68 %
- Air changes (per hr): 15
- Photoperiod (hrs dark / hrs light): 12/12

Study design: in vivo (LLNA)

Vehicle:

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

Remarks:

based on in-house trials

Concentration:

PIT: 100, 50, 25 and 10 %
Main: 100, 50, 10 and 0%

No. of animals per dose:

PIT: 1 female/dose
Main: 5 females/dose

Details on study design:

Preliminary Irritation Test: treatment on 2 consecutive days, ear was cleaned with tapwater 4 hours after last application
- Irritation: no irritation at any concentration
- Lymph node proliferation response: not measured

MAIN STUDY
ANIMAL ASSIGNMENT AND TREATMENT
- Name of test method: LLNA
- Criteria used to consider a positive response: stimulation index >=3

TREATMENT PREPARATION AND ADMINISTRATION:
Epidermal induction on the dorsal ear (25 uL) for 3 consecutive days at 0 (vehicle), 10, 50 and 100%. On day 6 injection with radiolabelled thymidine. After ca 5 hours animals were killed, draining lymphnodes were excised, examined visually (size estimated) and pooled per animal in 3 mL PBS. Tissues were processed and radioactivity was assessed using a scintilliation counter.

Positive control substance(s):

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

Statistics:

not performed

Results and discussion

In vivo (LLNA)

Results

Results 1

Parameter:

SI

Remarks on result:

other: see table

Results 2

Parameter:

other: disintegrations per minute (DPM)

Remarks on result:

other: see table

Any other information on results incl. tables

 

Concentration (% v/v) in acetone/ olive oil 4:1	dpm /group	Stimulation Index	Result
Vehicle	248 ± 119	1.0
10	196 ± 252	0.8 ± 1.4	Negative
50	634 ± 465	2.6 ± 0.9	Negative
100	369 ± 259	1.5 ± 0.8	Negative

 

Mortality/clinical signs: none

Body weight: no effects

Irritation: no effects

Applicant's summary and conclusion

Interpretation of results:

GHS criteria not met

Conclusions:

The substance is not sensitizing to the skin

Executive summary:

In a local lymphnode assay mice (3 females/treatment) received 3 daily applications of the substance at 0, 10, 50 and 100% at the dorsal site of the ear. After injection with radiolabelled thymidine, the SI was < 3 for all concentrations tested Therefore the substance is considered not sensitizing to the skin.