PDI oligomers, isocyanurate (3x)

Skin irritation / corrosion

Administrative data

Endpoint:

skin irritation: in vivo

Type of information:

experimental study

Adequacy of study:

key study

Study period:

6 February 2017 - 10 April 2017

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Justification for type of information:

An in vivo study was conducted for registration purposes in China.

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2017

Report date:

2017

Materials and methods

Test guideline

Test guideline 1

Qualifier:

according to guideline

Guideline:

OECD Guideline 404 (Acute Dermal Irritation / Corrosion)

Version / remarks:

28 July 2015

Deviations:

no

Test guideline 2

Qualifier:

according to guideline

Guideline:

other: ''Regulation on Test Methods for Chemical Substances”, Notification No. 2016-27, National Institute of Environmental Research, Republic of Korea

Version / remarks:

19 December 2016

Deviations:

no

GLP compliance:

yes

Test material

Test material information

Constituent 1

Reference substance name:

1,3,5-tris(5-isocyanatopentyl)-1,3,5-triazinane-2,4,6-trione

Cas Number:

119934-71-3

Molecular formula:

C21 H30 N6 O6

IUPAC Name:

1,3,5-tris(5-isocyanatopentyl)-1,3,5-triazinane-2,4,6-trione

Constituent 2

Reference substance name:

2-methylpropyl N-(5-isocyanatopentyl)-N-(5-isocyanatopentylcarbamoyl)carbamate

Molecular formula:

C18 H30 N4 O5

IUPAC Name:

2-methylpropyl N-(5-isocyanatopentyl)-N-(5-isocyanatopentylcarbamoyl)carbamate

Test material form:

liquid: viscous

Details on test material:

Appearance: colourless or light yellow viscous liquid
Storage conditions: at room temperature, container tightly closed, flushed with nitrogen.

Test animals

Species:

rabbit

Strain:

New Zealand White

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: Yonam College, Yonam Laboratory Animal (breeder); Orientbio Inc., Republic of Korea (supplier)
- Age at study initiation: 11 weeks
- Weight at study initiation: 2.16-2.25 kg
- Housing: one animal per cage in stainless wire mesh cages
- Diet: purina experimental diet for rabbit (38302AF; Cargill Agri Purina Inc.), ad libitum
- Water: tap water, filtered and irradiated by ultraviolet light, provided ad libitum
- Acclimation period: at least 5 days

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 19.1–22.1
- Humidity (%): 41.3–53.7
- Air changes (per hr): 10–15
- Photoperiod (hrs dark / hrs light): 12/12

IN-LIFE DATES: From: 21 February 2017 To: 9 March 2017

Test system

Type of coverage:

semiocclusive

Preparation of test site:

clipped

Vehicle:

unchanged (no vehicle)

Controls:

yes, concurrent no treatment

Amount / concentration applied:

Test material: 0.5 mL (applied on a patch)
Negative control: untreated patch

Duration of treatment / exposure:

4 hours

Observation period:

14 days

Number of animals:

3 (in a sequential manner)

Details on study design:

TEST SITE
- Area of exposure: 2.5 x 2.5 cm
- Type of wrap if used: application sites were covered with gauze (DaeHan Medical Supply Co., Ltd., Republic of Korea) and animals were wrapped with elastic bandage (3M Co., Ltd., Republic of Korea)

REMOVAL OF TEST SUBSTANCE The residual test substance was gently wiped off the test substance site with cotton moistened with tepid water.
- Time after start of exposure: 4 hours

OBSERVATION TIME POINTS
- Clinical signs: once daily
- Body weights: on the day of dosing (day 0) and the day of final observations (day 14)
- Evaluation of skin irritation: at 1, 24, 48 and 72 hours after patch removal and continued daily until day 14.


SCORING SYSTEM: According to OECD guideline 404

Results and discussion

In vivo

Results

Results 1

Irritation parameter:

erythema score

Basis:

animal: all three animals

Time point:

24/48/72 h

Score:

2

Max. score:

4

Remarks on result:

other: Erythema score 1 hour after patch removal: 1

Results 2

Irritation parameter:

edema score

Basis:

animal: all three animals

Time point:

24/48/72 h

Score:

0

Max. score:

4

Results 3

Irritation parameter:

erythema score

Basis:

animal: all three animals

Time point:

other: day 4 to day 8

Score:

1

Max. score:

4

Reversibility:

fully reversible within: 9 days

Irritant / corrosive response data:

The control sites did not reveal any sign of adverse skin reactions during the observation period.

Other effects:

- Other adverse local/systemic effects: scale, which was considered to be caused by the secondary change of stimulation, was observed in the initial and confirmatory tests from day 4 to day 14.
- Clinical signs: No adverse signs or symptoms were observed in any animal throughout the course of the study.
- Body weights: All animals exhibited normal body weight gain. The mean body weight gain throughout the observation period was 0.34 kg.

Applicant's summary and conclusion

Interpretation of results:

Category 3 (mild irritant) based on GHS criteria

Conclusions:

Based on the results of a skin irritation study, performed according to OECD 404 guideline, STABiO D-376N was considered to be ‘Slightly irritant’ to rabbit skin, and it was classified ‘Mild irritant (Category 3)’ according to the GHS classification.

Executive summary:

A skin irritation study was performed according to OECD 404 guideline and GLP principles. An initial test and a confirmatory test was performed, using 1 and 2 New Zealand White male rabbits, respectively. The test substance was applied undiluted on a patch, which was held in contact with the skin by a semi-occlusive dressing for 4 hours. After removal of the patch, observations of application sites were conducted at 1, 24, 48 and 72 hours. Because skin irriation was observed at 72 hours after patch removal, additional observation were conducted until day 14. Erythema (score 1 -2) was observed from 1 hour after patch removal to day 9. No edema was found but erythema (score 2) was well defined seen in all three animals at 24, 48 and 72 hours after patch removal. This effect was fully reversed after 9 days. No clinical signs or abnormal body weights were observed in any animal. Based on these results, STABiO D-376N was considered to be ‘Slightly irritant’ to rabbit skin, and it was classified ‘Mild irritant (Category 3)’ according to the GHS classification.