Registration Dossier

Administrative data

Description of key information

Cyclohexane, 5 -isocyanato-1 -(isocyanatomethyl)-1,3,3 -trimethyl-, homopolymer, caprolactam-blocked (IPDI homopolymer, caprolactam blocked) is not irritating to skin (Hüls AG, 1986).

The test substance is slightly irritating to eyes (Hüls AG, 1986), which do not meet criteria according to EC Regulation 1272/2008 to be classified as "iiritating to eyes".

With regard to local effects in the respiratory tract the substance is classified for repeated toxicity with STOT RE 1 (see chapter 'Repeated Dose Toxicity').

Key value for chemical safety assessment

Skin irritation / corrosion

Link to relevant study records
Reference
Endpoint:
skin irritation: in vivo
Type of information:
experimental study
Adequacy of study:
key study
Study period:
1986-03-07 to 1986-03-13
Reliability:
1 (reliable without restriction)
Rationale for reliability incl. deficiencies:
other: Guideline study
Qualifier:
according to
Guideline:
OECD Guideline 404 (Acute Dermal Irritation / Corrosion)
GLP compliance:
no
Species:
rabbit
Strain:
other: Small white Russian, Chbb-SPF
Details on test animals and environmental conditions:
TEST ANIMALS: 
- Strain: Small white Russian, Chbb-SPF
- Source: Dr. Karl Thomae GmbH, Biberach (Germany)
- Sex: male
- Weight at study initiation: 2.0 - 2.3 kg
Environmental conditions:
- Room temperature: 20°C (+/- 1°C)
- Hhumidity: 60% (+/- 5%)
- Air change: 15 times/hour
- Light: 12 hour light/dark rhythm
- Feed: K4 complete feed for rabbits (Ssniff, Soest, Germany)
- Water: tap water ad libitum
Type of coverage:
occlusive
Preparation of test site:
shaved
Vehicle:
other: water
Controls:
not required
Amount / concentration applied:
0.5 g test item was wetted with 0.5 ml water
Duration of treatment / exposure:
4 hour(s)
Observation period:
Post exposure period: 6 days
Number of animals:
3 males
Details on study design:
ADMINISTRATION/EXPOSURE 
- Area of exposure: 6 cm2
- Total quantity applied: 0.5 g wetted with 0.5 ml water
- Occlusion: mull patch, polyethylene film, elastic dressing
- Removal of test substance: The test material had turned solid and stuck  to the skin together with the patch, thus some force had to be exerted  carefully. After rinsing with water, some small particles remained on the  skin. 
EXAMINATIONS
- Examination time points: 1, 24, 48, 72 hours and 6 days after patch  removal; evaluation based on readings 1-4
- Scoring system: OECD; evaluation: VCI notes on safety data sheet and  Appendix VI of 79/831/EEC
Irritation parameter:
overall irritation score
Basis:
mean
Time point:
other: 60 min, 24, 48, 72 hrs
Score:
0
Max. score:
8
Remarks on result:
other: none of the three rabbits showed any test item related changes; test substance: IPDI homopolymer, caprolactam-blocked, approx. 100%
Irritation parameter:
erythema score
Basis:
mean
Time point:
other: 60 min, 24, 48, 72 hrs
Score:
0
Max. score:
4
Irritation parameter:
edema score
Basis:
mean
Time point:
other: 60 min, 24, 48, 72 hrs
Score:
0
Max. score:
4
Irritant / corrosive response data:
AVERAGE SCORE
- Erythema: 0.0
- Edema: 0.0
Other effects:
no other effects

no further results

Conclusions:
Under the present test conditions, none of the three male rabbits exposed for 4 hours to 500 mg cyclohexane, 5-isocyanato-1-(isocyanatomethyl)-1,3,3-trimethyl-, homopolymer, caprolactam-blocked (IPDI homopolymer, caprolactam-blocked) per patch and animal (occlusive condition) showed any test item-related changes at the examination time-points 60 minutes, 24, 48 and 72 hours after patch removal. Therfore, cyclohexane, 5-isocyanato-1-(isocyanatomethyl)-1,3,3-trimethyl-, homopolymer, caprolactam-blocked is not irritating to skin.
Executive summary:

The acute skin irritation properties of cyclohexane, 5-isocyanato-1-(isocyanatomethyl)-1,3,3-trimethyl-, homopolymer, caprolactam-blocked (IPDI homopolymer, caprolactam-blocked) were estimated according to OECD Guideline 404. A dose of 500 mg test item per animal was applied to the shaved, intact dorsal skin of 3 male rabbits under occlusive conditions. The test substance was administered undiluted, wetted with water. After the 4 -hour exposure period the patch was removed and the resulting reactions were examined. The average scores at 60 min, 24, 48 and 72 hours after patch removal are as follows: erythema/eschar: 0, edema: 0. Therefore, cyclohexane, 5-isocyanato-1-(isocyanatomethyl)-1,3,3-trimethyl-, homopolymer, caprolactam-blocked is not irritating to skin.

Endpoint conclusion
Endpoint conclusion:
no adverse effect observed (not irritating)

Eye irritation

Link to relevant study records
Reference
Endpoint:
eye irritation: in vivo
Type of information:
experimental study
Adequacy of study:
key study
Study period:
1986-03-07 to 1986-03-13
Reliability:
1 (reliable without restriction)
Rationale for reliability incl. deficiencies:
other: Guideline study
Qualifier:
according to
Guideline:
OECD Guideline 405 (Acute Eye Irritation / Corrosion)
GLP compliance:
no
Species:
rabbit
Strain:
other: Small white Russian, Chbb-SPF
Details on test animals or tissues and environmental conditions:
TEST ANIMALS: 
- Strain: Small white Russian, Chbb-SPF
- Source: Dr. Karl Thomae GmbH, Biberach (Germany)
- Sex: female
- Weight at study initiation: 2.4 - 2.6 kg
- Controls: untreated eye
Environmental conditions:
- Room temperature: 20°C (+/- 1°C)
- Hhumidity: 60% (+/- 5%)
- Air change: 15 times/hour
- Light: 12 hour light/dark rhythm
- Feed: K4 complete feed for rabbits (Ssniff, Soest, Germany)
- Water: tap water ad libitum
Vehicle:
unchanged (no vehicle)
Controls:
other: untreated eye
Amount / concentration applied:
undiluted
Amount applied: 0.1 g
Duration of treatment / exposure:
72 hour(s)
Observation period (in vivo):
Postexposure observation period: 6 days
Number of animals or in vitro replicates:
3 females
Details on study design:
ADMINISTRATION/EXPOSURE 
- Vehicle: none
- rinsed after 72 h
- Postexposure observation period: 6 days
EXAMINATIONS
- Ophtalmoscopic examination: 60 min, 24, 48, 72 hours, and 6 days after  treatment
- Tool used to assess score: sodium fluorescein / ophthalmic lamp /  visual inspections
- Scoring system: Draize (1959); evaluation: VCI notes on safety data  sheet and Appendix VI of 79/831/EEC
Irritation parameter:
overall irritation score
Basis:
mean
Time point:
other: 1, 24, 48, 72 h
Score:
8
Max. score:
110
Reversibility:
fully reversible within: 72 h
Irritation parameter:
cornea opacity score
Basis:
mean
Time point:
other: 24, 48, 72 h
Score:
0.56
Max. score:
4
Reversibility:
fully reversible within: 48 h
Irritation parameter:
iris score
Basis:
mean
Time point:
other: 24, 48, 72 h
Score:
0.33
Max. score:
2
Reversibility:
fully reversible within: 48 h
Irritation parameter:
conjunctivae score
Basis:
mean
Time point:
other: 24, 48, 72 h
Score:
0.67
Max. score:
3
Reversibility:
fully reversible within: 72 h
Irritation parameter:
chemosis score
Basis:
mean
Time point:
other: 24, 48, 72 h
Score:
0.11
Max. score:
4
Reversibility:
fully reversible within: 48 h
Irritant / corrosive response data:
AVERAGE SCORE
- Cornea: 0.56
- Iris: 0.33
- Conjunctivae (Redness): 0.67
- Conjunctivae (Chemosis): 0.11
- Overall irritation score: 8
REVERSIBILITY: complete within 72 hours
Other effects:
no other effects

no other results

Conclusions:
Under the conditions of this study cyclohexane, 5-isocyanato-1-(isocyanatomethyl)-1,3,3-trimethyl-, homopolymer, caprolactam-blocked (IPDI homopoymer, caprolactam blocked) showed slightly eye irritating effects in rabbits, which do not meet criteria according to EC Regulation 1272/2008 to be classified as "irritant to eyes".

Executive summary:

A study was performed to examine eye irritating effects of cyclohexane, 5-isocyanato-1-(isocyanatomethyl)-1,3,3-trimethyl-, homopolymer, caprolactam-blocked (IPDI homopoymer, caprolactam blocked) according to OECD TG 405. An amount of 0.1 g of the undiluted test substance was instilled into the conjunctival sac of the right eye of each of three female rabbits, and the untreated left eye served as control. The fluorescein test was performed 72 hours after instillation and thereafter the treated eyes were rinsed with warm NaCl solution. The eye reactions were monitored until the changes observed have completely subsided, however not for more than 21 days after application. Eye irritation index was assessed using Draize scale.

The test was evaluated as follows (average of evaluation at 24, 48 and 72 hours respectively): cornea: 0.56, iris: 0.33, conjunctivae: redness: 0.67 and chemosis: 0.11 (mean scores on Draize scale). All irritating effects were fully reversible within 72 hours. Therefore, under the conditions of this study Cyclohexane, 5-isocyanato-1-(isocyanatomethyl)-1,3,3-trimethyl-, homopolymer, caprolactam-blocked showed slightly eye irritating effects in rabbits, which do not meet criteria according to EC Regulation 1272/2008 to be classified as "irritating to eyes".

Endpoint conclusion
Endpoint conclusion:
no adverse effect observed (not irritating)

Respiratory irritation

Endpoint conclusion
Endpoint conclusion:
no adverse effect observed (not irritating)

Additional information

Cyclohexane, 5-isocyanato-1-(isocyanatomethyl)-1,3,3-trimethyl-, homopolymer, caprolactam-blocked (IPDI homopoymer, caprolactam blocked) is not irritating to skin of rabbits (OECD 404; Hüls AG, 1986).

The test substance showed slightly eye irritating effects in rabbits (OECD 405, Hüls AG, 1986), which do not meet citeria according to EC Regulation 1272/2008 to be classified as "irritating to eyes".

With regard to local effects in the respiratory tract the substance is classified for repeated toxicity with STOT RE 1 (see chapter 'Repeated Dose Toxicity').


Justification for selection of skin irritation / corrosion endpoint:
Only one study available.

Justification for selection of eye irritation endpoint:
Only one study available.

Justification for classification or non-classification

Based on the assessment of two animal studies (skin and eye irritating) and according to criteria of EC Regulation 1272/2008 cyclohexane, 5-isocyanato-1-(isocyanatomethyl)-1,3,3-trimethyl-, homopolymer, caprolactam-blocked (IPDI homopoymer, caprolactam blocked) is not irritating to skin and eyes.

With regard to local effects in the respiratory tract the substance is classified for repeated toxicity with STOT RE 1.

Thus, according to EU Regulation 1272/2008 no classification for respiratory tract irritation is warranted.