Nonane-1,9-diol

Skin sensitisation

Administrative data

Endpoint:

skin sensitisation: in vivo (LLNA)

Type of information:

experimental study

Adequacy of study:

weight of evidence

Study period:

2003-12-03 to 2003-12-08

Reliability:

3 (not reliable)

Rationale for reliability incl. deficiencies:

study well documented, meets generally accepted scientific principles, acceptable for assessment

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2004

Report date:

2004

Materials and methods

Test guideline

Qualifier:

equivalent or similar to guideline

Guideline:

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

Version / remarks:

2002

Deviations:

yes

Remarks:

Lymph node proliferation was assessed by total cell count and not via tritiated thymidine incorporation.

GLP compliance:

yes (incl. QA statement)

Type of study:

mouse local lymph node assay (LLNA)

Test material

Test material information

Constituent 1

Reference substance name:

Nonane-1,9-diol

EC Number:

223-517-5

EC Name:

Nonane-1,9-diol

Cas Number:

3937-56-2

Molecular formula:

C9H20O2

IUPAC Name:

nonane-1,9-diol

Specific details on test material used for the study:

SOURCE OF TEST MATERIAL
- Chemical name: 1,9-Nonanediol
- CAS no.: 3937-56-2
- Source and lot/batch No.of test material: : BASF / 42638
- Expiration date of the lot/batch: March 2003
- Molecular weight: 160.254 g/mol
- Purity: 98.8%

In vivo test system

Test animals

Species:

mouse

Strain:

CBA/Ca

Sex:

female

Details on test animals and environmental conditions:

Weight at dosing: 19.5 - 25.0g
Age: 9 wks
Source: Charles River Deutschland GmbH, Sulzfeld, Germany
Acclimation period: 15 days
Diet: Kliba-Labordiat (Provimi), ad libitum
Water: Municipal water, ad libitum
Housing: Singly housed
Temperature: 20-24°C
Humidity: 30-70%
Air changes: not stated
Photoperiod: 12 hours light/dark

Study design: in vivo (LLNA)

Vehicle:

propylene glycol

Concentration:

0, 10, 30, 60%

No. of animals per dose:

6

Details on study design:

1,9-Nonanediol was administered on 3 consecutive days to the dorsum of the ear of 6 female CBA mice/dose level. On each day of treatment the animals received an open application of 25 µL of the dose formulation. On day 6 all animals were sacrificed and each pair of draining auricular lymph nodes were collected from each animal. A single suspension of lymph node cells from each paired sample were prepared. Cell count was determined using a Casy-Counter.

Positive control substance(s):

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

Statistics:

Wilcoxon test

Results and discussion

Positive control results:

The positive control, alpha-hexylcinnamaldehyde, tech. 85% had a sensitising potential in the LLNA assay, thereby demonstrating the sensitivity and specificity of the assay.

In vivo (LLNA)

Results

Results 1

Parameter:

other: Relative lymph node weight index

Value:

ca. 1

Test group / Remarks:

Vehicle control / 6 animals

Results 2

Parameter:

other: Relative lymph node weight index

Value:

ca. 0.95

Test group / Remarks:

10% in propylene glycol / 6 animals

Results 3

Parameter:

other: Relative lymph node weight index

Value:

ca. 0.87

Test group / Remarks:

30% in propylene glycol / 6 animals

Results 4

Parameter:

other: Relative lymph node weight index

Value:

ca. 0.76

Test group / Remarks:

60% in propylene glycol / 6 animals

Results 5

Parameter:

other: Relative lymph node cell count index

Value:

ca. 1

Test group / Remarks:

Vehicle control / 6 animals

Results 6

Parameter:

other: Relative lymph node cell count index

Value:

ca. 1.05

Test group / Remarks:

10% in propylene glycol / 6 animals

Results 7

Parameter:

other: Relative lymph node cell count index

Value:

ca. 0.92

Test group / Remarks:

30% in propylene glycol / 6 animals

Results 8

Parameter:

other: Relative lymph node cell count index

Value:

ca. 0.88

Test group / Remarks:

60% in propylene glycol / 6 animals

Results 9

Parameter:

SI

Test group / Remarks:

Vehicle control / 6 animals

Remarks on result:

not measured/tested

Results 10

Parameter:

SI

Test group / Remarks:

10% propylene glycol / 6 animals

Remarks on result:

not measured/tested

Results 11

Parameter:

SI

Test group / Remarks:

30% in propylene glycol / 6 animals

Remarks on result:

not measured/tested

Results 12

Parameter:

SI

Test group / Remarks:

60% in propylene glycol

Remarks on result:

not measured/tested

Cellular proliferation data / Observations:

refer to Table 7.4.1/01

Any other information on results incl. tables

There were no clinical signs of toxicity observed, with all animals gaining weight. All animals receiving 1,9-Nonanediol at 10, 30 and 60% did not induce a statistically significant increase in either lymph node weight or lymph node cell counts.

A statistically significant increase in ear weight was observed in animals treated at 30%, this however was not deemed biologically relevant as it was not dose related.

Table 7.4.1/01:
Individual and group mean data

Group (%)	Lymph node weight (mg)	Lymph node weight index^1	Lymph node cell count	Lymph node index^1	Ear weight (mg)	Ear weight index^1
Untreated	4.3 ±0.7	0.89	6296833	0.89	27.8 ±2.3	0.97
Vehicle (propylene glycol)	4.9± 0.5	1.00	7082167	1.00	28.7 ±1.8	1.00
10%	4.6 ±0.4	0.95	7458833	1.05	30.4 ±1.3	1.06
30%	4.3 ±0.5	0.87	6546500	0.92	31.1 ±1.8	1.08*
60%	3.7 ±0.8	0.76	6232167	0.88	29.9 ±0.9	1.04
Positive control
Vehicle (acetone)	-	1.00	-	1.00	-	1.00
1% HCA in acetone	-	1.08	-	1.25	-	1.07*
3% HCA in acetone	-	1.21*	-	1.56*	-	1.14**
10% HCA in acetone	-	1.73**	-	2.58**	-	1.14**
* test group / vehicle control * p<0.05; ** p<0.01

Deficiencies:

Lymph node proliferation was assessed by total cell count and not via tritiated thymidine incorporation.

Ear erythema was not assessed by thickness at the end of treatment, but via ear weight. A defined area of 0.8 cm was punched out of the apical part of each ear and for each animal the weight of the pooled punches was determined in order to obtain an indication of possible skin irritation.

Evidence of skin sensitisation was based on statistically significant increases in lymph node cell count and/or lymph node weight compared to the vehicle control. Whilst it is recognised that this study is insufficient in addressing the endpoint sufficiently, a weight of evidence approach has been taken to address this endpoint conclusively.

Applicant's summary and conclusion

Interpretation of results:

study cannot be used for classification

Conclusions:

Under the condition of the study, administration of 1,9-Nonanediol to mice at concentrations of 10%, 30% or 60% resulted in lymph node cell counts and lymph node weights which were comparable to the vehicle control. In accordance with the criteria defined by Ulrich et al (2001) 1,9-Nonanediol was not considered to be a skin sensitizer. This study provides supportive information but it is not suitable for classification and labelling purposes.

Executive summary:

1,9-Nonanediol was administered on 3 consecutive days to the dorsum of the ear of 6 female CBA mice/dose level. On each day of treatment the animals received an open application of 25 µL of the dose formulation. On day 6 all animals were sacrificed and each pair of draining auricular lymph nodes were collected from each animal. A single suspension of lymph node cells from each paired sample were prepared. Cell count was determined using a Casy-Counter. 

The weight of ear punches taken from the areas of test article application as a measure of inflammatory ear swelling was determined, serving as an indicator for the irritant action of the test article.

A positive control study was conducted using hexylcinnamic aldehyde (HCA) approximately six-months before the study on 1,9-Nonanediol and confirmed the specificity and sensitivity of the assay.

There were no clinical signs of toxicity observed, with all animals gaining weight. All animals receiving 1,9-Nonanediol at 10, 30 and 60% did not induce a statistically significant increase in either lymph node weight or lymph node cell counts.

A statistically significant increase in ear weight was observed in animals treated at 30%, this however was not deemed biologically relevant as it was not dose related.

Under the condition of the study, administration of 1,9-Nonanediol to mice at concentrations of 10%, 30% or 60% resulted in lymph node cell counts and lymph node weights which were comparable to the vehicle control. In accordance with the criteria defined by Ulrich et al (2001) 1,9-Nonanediol was not considered to be a skin sensitizer. This study provides supportive information but it is not suitable for classification and labelling purposes.