Nonanoic acid

Skin irritation / corrosion

Administrative data

Endpoint:

skin irritation: in vivo

Type of information:

experimental study

Adequacy of study:

key study

Study period:

From 18 SEP 2001 to 16 OCT 2001

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2001

Report date:

2001

Materials and methods

Test guideline

Test guideline 1

Qualifier:

according to guideline

Guideline:

EU Method B.4 (Acute Toxicity: Dermal Irritation / Corrosion)

Test guideline 2

Qualifier:

according to guideline

Guideline:

OECD Guideline 404 (Acute Dermal Irritation / Corrosion)

GLP compliance:

yes (incl. QA statement)

Remarks:

in accordance with SN EN 45001 (Swiss legislation)

Test material

Test material information

Constituent 1

Reference substance name:

Nonanoic acid

EC Number:

203-931-2

EC Name:

Nonanoic acid

Cas Number:

112-05-0

Molecular formula:

C9H18O2

IUPAC Name:

nonanoic acid

Test material form:

liquid

Details on test material:

- Name of test material (as cited in study report): N-nonanoic acid
- Physical state: liquid
- Analytical purity: 97.27 %
- Stability under test conditions: stable under storage conditions (room temperature, away from sunlight)

Test animals

Species:

rabbit

Strain:

New Zealand White

Test system

Type of coverage:

semiocclusive

Preparation of test site:

shaved

Vehicle:

unchanged (no vehicle)

Controls:

no

Amount / concentration applied:

undiluted

Duration of treatment / exposure:

4 hour(s)

Observation period:

immediately after end of exposure, 24, 48 and 72 h and 7, 10 and 14 days post exposure

Number of animals:

3

Details on study design:

SCORING SYSTEM: according to guideline OECD 404F

Results and discussion

In vivo

Results

Results 1

Irritation parameter:

erythema score

Basis:

animal #1

Time point:

24/48/72 h

Score:

3

Max. score:

4

Reversibility:

fully reversible within: 14 days

Results 2

Irritation parameter:

erythema score

Basis:

animal #2

Time point:

24/48/72 h

Score:

3.33

Max. score:

4

Reversibility:

fully reversible within: 14 days

Results 3

Irritation parameter:

erythema score

Basis:

animal #3

Time point:

24/48/72 h

Score:

2.33

Max. score:

4

Reversibility:

fully reversible within: 14 days

Results 4

Irritation parameter:

edema score

Basis:

animal #1

Time point:

24/48/72 h

Score:

2

Max. score:

4

Reversibility:

fully reversible within: 14 days

Results 5

Irritation parameter:

edema score

Basis:

animal #2

Time point:

24/48/72 h

Score:

2.33

Max. score:

4

Reversibility:

fully reversible within: 14 days

Results 6

Irritation parameter:

edema score

Basis:

animal #3

Time point:

24/48/72 h

Score:

2

Max. score:

4

Reversibility:

fully reversible within: 14 days

Any other information on results incl. tables

After 1 h post-exposure: Well-defined erythema (score 2/2/2) and very slight to slight edema (score 2/2/1)

After 24 h: Moderate to severe erythema (score 3/3/2) and slight edema(score 2/2/2).
After 48 h: Moderate to severe erythema (score 3/3/3)and slight edema (score 2/2/2)

After 72 h: Well-defined to severe erythema (score 3/4/2)and slight edema (score 2/3/2), scaling in one animal

After 7 days: Very slight to well-defined erythema (score 2/2/1)and very slight edema (score 1/1/1), scaling in all animals

After 10 days: Very slight erythema (score 1/1/1)and very slight edema (score 1/0/1), scaling in all animal

After 14 days: no edema, no erythema, scaling in 2 of 3 animals

The mean scores across the 3 animals were 
       Erythema     Edema
===============================
24 h     2.7           2
48 h     3             2
72 h     3             2.3
================================

The mean scores across three scoring times (24, 48, 72 h) for the individual animals were 3.00, 3.33,  and 2.33 (erythema/eschar) and 2.00, 2.33, and 2.00 (edema),  respectively. Well-defined to moderate/severe erythema in all animals for  72 h, and very slight to moderate edema for up to 10 d, all effects disappearing 14 d after treatment.  

No corrosive effects were noted.

In a pre-study with exposure for 3 min and 1 h in one animal, skin  reactions appeared in the form of well-defined to moderate erythema  within one to 24 h p.a. and were still visible after 7d.

Applicant's summary and conclusion

Interpretation of results:

Category 2 (irritant) based on GHS criteria

Conclusions:

Under the conditions of this study, the test substance was irritating.

Executive summary:

3 New Zealand white rabbits were dermally exposed to the undiluted test substance (purity: 97.27%; 0.5 mL fluid were soaked into 6 cm² gauze patch) according to guidelines EU B4 and OECD 404. After 4 h of semiocclusive exposure, the test substance caused well-defined to severe erythema (mean score: 2.89) and very slight to moderate edema (mean score: 2.11). After 72 h, one animal out of three showed scaling of the treated area, after 7 and 10 days all animals and after 14 days 2 of 3 animals. The test item thus revealed irritating effects (Celanese/RCC, 2001).

This study was judged to be reliable (RL1).