2-(4-tert-butylbenzyl)propionaldehyde

Skin sensitisation

Administrative data

Endpoint:

skin sensitisation: in vivo (LLNA)

Type of information:

experimental study

Adequacy of study:

weight of evidence

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: Comparable to guideline standards with acceptable restrictions (no data on GLP status)

Data source

Reference

Reference 1

Reference Type:

publication

Title:

Ethanol and diethyl phthalate: Vehicle effects in the local lymph node assay

Author:

Lalko J., Isola D. and Api A.M

Year:

2004

Bibliographic source:

International Journal of Toxicology, 23, 171-177

Reference 2

Reference Type:

secondary source

Title:

Vehicle effects in the murine Local Lymph Node Assay (LLNA)

Author:

Isola D. and Lalko J.

Year:

2001

Bibliographic source:

International Journal of Toxicology, 20(6), 401 [as cited in RIFM and FEMA Fragrance and Flavour Database (online), 188, Location 38352, updated 28-Apr-08]

Reference 3

Reference Type:

secondary source

Title:

Report to RIFM by Johnson et al - Local Lymph Node Assay with p-t-Butyl-a-methylhydrocinnamic aldehyde - Local Lymph Node Assay skin mouse

Author:

Johnson I.R., Parker G. and Allen S.

Year:

2001

Bibliographic source:

RIFM and FEMA Fragrance and Flavour Database (online), 188, Location 37065, 37066, 37067, 37068, updated 25-Apr-08

Materials and methods

Test guideline

Qualifier:

equivalent or similar to guideline

Guideline:

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

Version / remarks:

(1992)

Principles of method if other than guideline:

Kimber & Basketter 1992, Kimber et al. 1994

GLP compliance:

not specified

Type of study:

mouse local lymph node assay (LLNA)

Test material

Test material information

Constituent 1

Reference substance name:

2-(4-tert-butylbenzyl)propionaldehyde

EC Number:

201-289-8

EC Name:

2-(4-tert-butylbenzyl)propionaldehyde

Cas Number:

80-54-6

Molecular formula:

C14H20O

IUPAC Name:

3-(4-tert-butylphenyl)-2-methylpropanal

Details on test material:

- Source: Givaudan (Switzerland)
- Analytical purity: 98.6%

In vivo test system

Test animals

Species:

mouse

Strain:

other: CBA/CA/Ola/Hsd

Sex:

male

Details on test animals and environmental conditions:

TEST ANIMALS
- Source: Harlan Interfauna UK, Shaw's Farm, Blackthorne, Bicester, Oxon, UK)
- Age at study initiation: 8-12 weeks
- Housing: 4/cage
- Diet: ad libitum, Special Diets Services Ltd [SDS] Porton Combined Diet [PCD] pelleted diet
- Water: ad libitum

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 19-25
- Humidity (%): 30-70
- Photoperiod (hrs dark / hrs light): 12/12

Study design: in vivo (LLNA)

Vehicle:

other: Trial 1: ethanol, Trial 2: diethyl phthalate (DEP), Trial 3: 25% ethanol/75% diethyl phthalate (DEP), Trial 4: 75% ethanol/25% diethyl phthalate (DEP)

Concentration:

0; 0.3; 1; 3; 10; 30; 50 %

No. of animals per dose:

4

Details on study design:

ANIMAL ASSIGNMENT AND TREATMENT
- in accordance to guideline 429 (OECD)

TREATMENT PREPARATION AND ADMINISTRATION:
- Number of animals /group: n=4
- Site of application: dorsum of both ears
- Volume of applied: 25µl
- Frequency of application: once daily for 3 days
- Administration of radioactive marker: 48 h after application of test substance
- Radioactive marker: 20 µCi of a 2.0 Ci/mmol specific activity (3)H-methyl thymidine (in 250µl PBS)
- Sacrifice: 5 hours post application of radioactive marker
- Preparation of Lymph nodes: Pursuant to guideline 429 (OECD), pooled treatment group approach

Positive control substance(s):

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

Statistics:

The results are expressed as counts per minute (cpm) value per lymph node for each group. The activity of each test group is then divided by the activity of the vehicle control group to give a test:control ratio for each concentration.

Results and discussion

In vivo (LLNA)

Results

Results 1

Parameter:

SI

Remarks on result:

other: see tables below

Results 2

Parameter:

other: disintegrations per minute (DPM)

Remarks on result:

other: see tables below

Any other information on results incl. tables

Table 1: Tabular representation of the results of trial 1 (based on 8 lymph nodes assayed).

Trial 1 (vehicle: ethanol)
Doses (%)	CPM	CPM per lymph node / 100	Stimulation index
1	1728	2.16	1.62
3*	3216	4.02	3.02
10*	4816	6.02	4.53
30*	8968	11.2	8.41
50*	16672	20.8	15.67

Table 2: Tabular representation of the results of trial 2 (based on 8 lymph nodes assayed)

Trial 2 (vehicle: diethyl phthalate (DEP))
Doses (%)	CPM	CPM per lymph node / 100	Stimulation index
1	2858	3.57	1.93
3	3894	4.87	2.63
10*	7178	8.97	4.85
30*	8767	10.96	5.92
50*	13642	17.05	9.22

Table 3: Tabular representation of the results of trial 3 (based on 8 lymph nodes assayed)

Trial 3 (vehicle: 25% ethanol/75% diethyl phthalate (DEP))
Doses (%)	CPM	CPM per lymph node /100	Stimulation index
0.3	2816	3.65	1.27
1	2979	3.72	1.30
3	2910	3.64	1.27
10	5889	7.36	2.56
30*	11036	13.80	4.81

Table 4: Tabular representation of the results of trial 1 (based on 8 lymph nodes assayed)

Trial 4 (vehicle: 75% ethanol/25% diethyl phthalate (DEP))
Doses (%)	CPM	CPM per lymph node / 100	Stimulation index
0.3	1304	1.63	0.87
1	1577	1.97	1.05
3	2341	2.93	1.57
10*	4914	6.14	3.28
30*	12776	15.57	8.54

For tables  1-4; * denotes concentrations with an increase in isotope incorporation greater than 3-fold

Concentration of the test substance required to produce a 3-fold increase (EC3, calculated)

- Trial 1: 2.97% (w/v) in ethanol

- Trial 2: 4.17 % (w/v) in diethyl pthalate

- Trial 3: 13.91 % (w/v) in 25% ethanol/75% DEP

- Trial 4: 8.85% (w/v) in 75% ethanol/25% DEP