Polyurea, produced by reacting aryl isocyanate with alkyl amines

Endpoint summary

Description of key information

In vivo studies on dermal and ocular irritation have been conducted on Diurea 8. No classifiable irritant responses were observed when applied to skin. For potential eye irritancy, Diurea 8 was unclassified according to the Classification, Labelling and Packaging Regulation.
No data were identified relating to irritation to the respiratory tract. Given the results from the skin and eye irritation studies it is unlikely that Diurea 8 would cause significant respiratory irritation.

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:

The study was performed between 15 November 2011 and 18 November 2011

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: Study conducted in compliance with agreed protocols, with no or minor deviations from standard test guidelines and/or minor methodological deficiencies, which do not affect the quality of the relevant results.

Qualifier:

according to guideline

Guideline:

OECD Guideline 404 (Acute Dermal Irritation / Corrosion)

Deviations:

no

Qualifier:

according to guideline

Guideline:

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

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Species:

rabbit

Strain:

New Zealand White

Details on test animals or test system and environmental conditions:

Three New Zealand White (Hsdlf:NZW) strain rabbits were supplied by Harlan Laboratories UK Ltd., Leicestershire, UK. At the start of the study the animals weighed 2.25 to 3.20 kg and were twelve to twenty weeks old. After an acclimatisation period of at least five days each animal was given a number unique within the study which was written with a black indelible marker-pen on the inner surface of the ear and on the cage label.
The animals were individually housed in suspended cages. Free access to mains drinking water and food (2930 Teklad Global Certified Rabbit diet supplied by Harlan Laboratories UK Ltd., Oxon, UK) was allowed throughout the study. The diet and drinking water were considered not to contain any contaminant of a level that might have affected the purpose or integrity of the study.
The temperature and relative humidity were set to achieve limits of 17 to 23°C and 30 to 70% respectively. Any occasional deviations from these targets were considered not to have affected the purpose or integrity of the study. The rate of air exchange was at least fifteen changes per hour and the lighting was controlled by a time switch to give twelve hours continuous light (06:00 to 18:00) and twelve hours darkness.
The animals were provided with environmental enrichment items which were considered not to contain any contaminant of a level that might have affected the purpose or integrity of the study.

Type of coverage:

semiocclusive

Preparation of test site:

other: clipped

Vehicle:

other: test material was moistened with 0.5 ml of distilled water.

Controls:

no

Amount / concentration applied:

0.5 g of the test item, moistened sufficiently with 0.5 ml of distilled water,

Duration of treatment / exposure:

4 hours

Observation period:

72 hours

Number of animals:

3

Details on study design:

On the day before the test each of a group of three rabbits was clipped free of fur from the dorsal/flank area using veterinary clippers. Only animals with a healthy intact epidermis by gross observation were selected for the study.
On the day of the test a suitable test site was selected on the back of each rabbit. At each test site a quantity of 0.5 g of the test item, moistened sufficiently with 0.5 ml of distilled water, was introduced under a 2.5 cm x 2.5 cm cotton gauze patch. The patch was secured in position with a strip of surgical adhesive tape. To prevent the animals interfering with the patches, the trunk of each rabbit was wrapped in an elasticated corset and the animals were returned to their cages for the duration of the exposure period.
Four hours after application the corset and patches were removed from each animal and any residual test item removed by gentle swabbing with cotton wool soaked in distilled water.

Irritation parameter:

erythema score

Basis:

animal: 71324 male

Time point:

other: Highest score at 1, 24, 48 and 72 hours

Score:

0

Max. score:

4

Reversibility:

other: No evidence of skin irritation

Irritation parameter:

erythema score

Basis:

animal: 71325 Male

Time point:

other: Highest score at 1, 24, 48 and 72 hours

Score:

0

Max. score:

4

Reversibility:

other: No evidence of skin irritation

Irritation parameter:

erythema score

Basis:

animal: 71326 male

Time point:

other: Highest score at 1, 24, 48 and 72 hours

Score:

0

Max. score:

4

Reversibility:

other: No evidence of skin irritation

Irritation parameter:

other: Oedema Formation

Basis:

animal: 71324 male

Time point:

other: Highest score at 1, 24, 48 and 72 hours

Score:

0

Max. score:

4

Reversibility:

other: No evidence of skin irritation

Irritation parameter:

edema score

Basis:

animal: 71325 male

Time point:

other: Highest score at 1, 24, 48 and 72 hours

Score:

0

Max. score:

4

Reversibility:

other: No evidence of skin irritation

Irritation parameter:

edema score

Basis:

animal: 71326 male

Time point:

other: Highest score at 1, 24, 48 and 72 hours

Score:

0

Max. score:

4

Reversibility:

other: No evidence of skin irritation

Irritant / corrosive response data:

The individual scores for erythema/eschar and oedema are given in Table 1.
No evidence of skin irritation was noted during the study.

Other effects:

Individual bodyweights and bodyweight changes are given in Table 2.
All animals showed expected gain in bodyweight during the study.

Measurement of pH

The pH of the test item was determined prior to commencement of the study and found to be as follows:

Preparation	pH Measurement
	immediately	after 10 minutes
10% w/w aqueous preparation of the test item	9.1	9.1

Table 1              Individual Skin Reactions

Skin Reaction	Observation Time (following patch removal)	Individual Scores – Rabbit Number and Sex			Total
		71324Male	71325Male	71326Male
Erythema/Eschar Formation	Immediately	0	0	0	(0 )
	1 Hour	0	0	0	( 0 )
	24 Hours	0	0	0	0
	48 Hours	0	0	0	( 0 )
	72 Hours	0	0	0	0
Oedema Formation	Immediately	0	0	0	( 0 )
	1 Hour	0	0	0	( 0 )
	24 Hours	0	0	0	0
	48 Hours	0	0	0	( 0 )
	72 Hours	0	0	0	0
Sum of 24 and 72‑HourReadings(S)      :          0
Primary Irritation Index (S/6)                   :          0/6 = 0.0
Classification                                        :          NON‑IRRITANT

 

(   ) = Total values not used for calculation of primary irritation index

Table 2              Individual Bodyweights and Bodyweight Changes

Rabbit Number and Sex	Individual Bodyweight (kg)		Bodyweight Change (kg)
	Day 0	Day 3
71324Male	2.25	2.35	0.10
71325Male	2.33	2.44	0.11
71326Male	3.20	3.34	0.14

Interpretation of Results

Calculation of Primary Irritation Index and Grading of Irritancy Potential Using the Draize Scheme

The scores for erythema and oedema at the 24 and 72-hour readings were totalled for the three test rabbits (12 values) and this total was divided by six to give the primary irritation index of the test material. The test material was classified according to the following scheme devised by Draize J H (1959) "Dermal Toxicity" In: Appraisal of the Safety of Chemicals in Foods, Drugs and Cosmetics. Association of Food and Drug Officials of the,,, p.47:

Primary Irritation Index	Classification of Irritancy
0	Non-irritant
> 0 to 2	Mild irritant
> 2 to 5	Moderate irritant
> 5 to 8	Severe irritant

If irreversible alteration of the dermal tissue is noted in any rabbit, as judged by the Study Director, which include ulceration and clear necrosis or signs of scar tissue, the test material is classified as corrosive to rabbit skin. Classification according to Draize may, therefore, not be applicable.

The results were also evaluated according to the Classification, Labelling and Packaging Regulation and the Globally Harmonised System of Classification and Labelling of Chemicals.

Interpretation of results:

not irritating

Remarks:

Migrated information Criteria used for interpretation of results: other: Draize

Conclusions:

The test item produced a primary irritation index of 0.0 and was classified as non irritant to rabbit skin according to the Draize classification scheme. No corrosive effects were noted.
The test item did not meet the criteria for classification according to the Classification, Labelling and Packaging Regulation or the Globally Harmonised Classification System.

Executive summary:

Introduction. The study was performed to assess the irritancy potential of the test item to the skin of the New Zealand White rabbit. The method was designed to be compatible with the following:

OECD Guidelines for the Testing of Chemicals No. 404 “Acute Dermal Irritation/Corrosion” (adopted 24 April 2002)

Method B4 Acute Toxicity (Skin Irritation) of CommissionRegulation (EC) No. 440/2008

Results. A single 4‑Hour, semi-occluded application of the test item to the intact skin of three rabbits produced no evidence of skin irritation.

Conclusion. The test item produced a primary irritation index of 0.0 and was classified as non‑irritant to rabbit skin according to the Draize classification scheme. No corrosive effects were noted.

The test item did not meet the criteria for classification according to the Classification, Labelling and Packaging Regulation or the Globally Harmonised Classification System.

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:

The study was performed between 24 November 2011 and 08 December 2011

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: Study conducted in compliance with agreed protocols, with no or minor deviations from standard test guidelines and/or minor methodological deficiencies, which do not affect the quality of the relevant results.

Qualifier:

according to guideline

Guideline:

OECD Guideline 405 (Acute Eye Irritation / Corrosion)

Deviations:

no

Qualifier:

according to guideline

Guideline:

EU Method B.5 (Acute Toxicity: Eye Irritation / Corrosion)

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Species:

rabbit

Strain:

New Zealand White

Details on test animals or tissues and environmental conditions:

Three New Zealand White (Hsdlf:NZW) strain rabbits were supplied by Harlan Laboratories UK Ltd., Leicestershire, UK. At the start of the study the animals weighed 2.45 to 2.75 kg and were twelve to twenty weeks old. After an acclimatisation period of at least five days each animal was given a number unique within the study which was written with a black indelible marker-pen on the inner surface of the ear and on the cage label.
The animals were individually housed in suspended cages. Free access to mains drinking water and food (2930 Teklad Global Certified Rabbit diet supplied by Harlan Laboratories UK Ltd., Oxon, UK) was allowed throughout the study. The diet and drinking water were considered not to contain any contaminant of a level that might have affected the purpose or integrity of the study.
The temperature and relative humidity were set to achieve limits of 17 to 23°C and 30 to 70% respectively. Any occasional deviations from these targets were considered not to have affected the purpose or integrity of the study. The rate of air exchange was at least fifteen changes per hour and the lighting was controlled by a time switch to give twelve hours continuous light (06:00 to 18:00) and twelve hours darkness.
The animals were provided with environmental enrichment items which were considered not to contain any contaminant of a level that might have affected the purpose or integrity of the study.

Vehicle:

unchanged (no vehicle)

Controls:

other: The left eye remained untreated and was used for control purposes.

Amount / concentration applied:

0.1 ml of the test item, which was found to weigh approximately 75 mg

Duration of treatment / exposure:

Up to 1 hour

Observation period (in vivo):

Approximately 1 hour and 24, 48 and 72 hours following treatment

Number of animals or in vitro replicates:

3 animals were tested in total. (After consideration of the ocular responses produced in the first treated animal, two additional animals were treated. )

Details on study design:

Immediately before the start of the test, both eyes of the provisionally selected test rabbits were examined for evidence of ocular irritation or defect with the aid of a light source from a standard ophthalmoscope. Only animals free of ocular damage were used.
Initially, a single rabbit was treated. A volume of 0.1 ml of the test item, which was found to weigh approximately 75 mg (as measured by gently compacting the required volume into an adapted syringe) was placed into the conjunctival sac of the right eye, formed by gently pulling the lower lid away from the eyeball. The upper and lower eyelids were held together for about one second immediately after treatment, to prevent loss of the test item, and then released. The left eye remained untreated and was used for control purposes. Immediately after administration of the test item, an assessment of the initial pain reaction was made according to the six point scale shown in Appendix 1.
After consideration of the ocular responses produced in the first treated animal, two additional animals were treated.
Assessment of ocular damage/irritation was made approximately 1 hour and 24, 48 and 72 hours following treatment, according to the numerical evaluation given in Appendix 2, (from Draize J H (1977) "Dermal and Eye Toxicity Tests" In: Principles and Procedures for Evaluating the Toxicity of Household Substances, National Academy of Sciences, Washington DC p.48 to 49).
Any other ocular effects were also noted. Examination of the eye was facilitated by the use of the light source from a standard ophthalmoscope.
Any clinical signs of toxicity, if present, were also recorded.
Individual bodyweights were recorded on Day 0 (the day of dosing) and at the end of the observation period.

Irritation parameter:

cornea opacity score

Basis:

animal: 71360 Male

Time point:

other: Highest score at 1, 24, 48 and 72 hours

Score:

0

Max. score:

4

Reversibility:

other: No effects observed

Irritation parameter:

cornea opacity score

Basis:

animal: 71413 Male

Time point:

other: Highest score at 1, 24, 48 and 72 hours

Score:

0

Max. score:

4

Reversibility:

not specified

Remarks:

No effects observed

Irritation parameter:

cornea opacity score

Basis:

animal: 71414 Male

Time point:

other: Highest score at 1, 24, 48 and 72 hours

Score:

0

Max. score:

4

Reversibility:

other: No effects observed

Irritation parameter:

iris score

Basis:

animal: 71360 Male

Time point:

other: Highest score at 1, 24, 48 and 72 hours

Score:

0

Max. score:

2

Reversibility:

other: no effects observed

Irritation parameter:

iris score

Basis:

animal: 7413 Male

Time point:

other: Highest score at 1, 24, 48 and 72 hours

Score:

0

Max. score:

2

Reversibility:

other: no effects observed

Irritation parameter:

iris score

Basis:

animal: 7414 Male

Time point:

other: Highest score at 1, 24, 48 and 72 hours

Score:

0

Max. score:

2

Reversibility:

other: no effects observed

Irritation parameter:

other: redness

Basis:

animal: 71360 Male

Time point:

other: Highest score at 1, 24, 48 and 72 hours

Score:

1

Max. score:

3

Reversibility:

fully reversible within: 48 hours

Irritation parameter:

other: redness

Basis:

animal: 7413 Male

Time point:

other: Highest score at 1, 24, 48 and 72 hours

Score:

1

Max. score:

3

Reversibility:

fully reversible within: 24 hours

Irritation parameter:

other: redness

Basis:

animal: 7414 Male

Time point:

other: Highest score at 1, 24, 48 and 72 hours

Score:

1

Max. score:

3

Reversibility:

fully reversible within: 48 hours

Irritation parameter:

chemosis score

Basis:

animal: 71360 Male

Time point:

other: Highest score at 1, 24, 48 and 72 hours

Score:

1

Max. score:

4

Reversibility:

fully reversible within: 72 hours

Irritation parameter:

chemosis score

Basis:

animal: 71413 Male

Time point:

other: Highest score at 1, 24, 48 and 72 hours

Score:

1

Max. score:

4

Reversibility:

fully reversible within: 48 hours

Irritation parameter:

chemosis score

Basis:

animal: 71414 Male

Time point:

other: Highest score at 1, 24, 48 and 72 hours

Score:

1

Max. score:

4

Reversibility:

fully reversible within: 72 hours

Irritant / corrosive response data:

Ocular Reactions
Individual and group mean scores for ocular irritation are given in Table 1 and Table 2.
No corneal or iridial effects were noted during the study.
Minimal conjunctival irritation was noted in all treated eyes one and 24 hours after treatment. Minimal conjunctival discharge persisted in one treated eye at the 48 Hour observation.
Two treated eyes appeared normal at the 48 Hour observation and one treated eye appeared normal at the 72 Hour observation

Other effects:

Bodyweight
Individual bodyweights and bodyweight changes are given in Table 3.
All animals showed expected gain in bodyweight during the study.

 Interpretation of Results

The numerical values corresponding to each animal, tissue and observation time were recorded. The data relating to the conjunctivae were designated by the letters A (redness), B (chemosis) and C (discharge), those relating to the iris designated by the letter D and those relating to the cornea by the letters E (degree of opacity) and F (area of cornea involved). For each tissue the score was calculated as follows:

Score for conjunctivae        =         (A + B + C) x 2
Score for iris                         =         D x 5
Score for cornea                  =         (E x F) x 5

Using the numerical data obtained a modified version of the system described by Kay J H and Calandra J C (1962), J. Soc. Cosmet. Chem.13, 281‑289 (see Appendix 3) was used to classify the ocular irritancy potential of the test item. This was achieved by adding together the scores for the cornea, iris and conjunctivae for each time point for each rabbit. The group means of the total scores for each observation were calculated. The highest of these group means (the maximum group mean score) together with the persistence of the reactions enabled classification of the eye irritancy potential of the test item.

If evidence of irreversible ocular damage is noted, the test item will be classified as corrosive to the eye.

Table 1              Individual Scores and Individual Total Scores for Ocular Irritation

Rabbit Number and Sex	71360Male				71413Male				71414Male
	IPR= 2				IPR = 2				IPR = 2
Time After Treatment	1 Hour	24 Hours	48 Hours	72 Hours	1 Hour	24 Hours	48 Hours	72 Hours	1 Hour	24 Hours	48 Hours	72 Hours
CORNEA
E = Degree of Opacity	0	0	0	0	0	0	0	0	0	0	0	0
F = Area of Cornea Involved	0	0	0	0	0	0	0	0	0	0	0	0
Score (E x F) x 5	0	0	0	0	0	0	0	0	0	0	0	0
IRIS
D	0	0	0	0	0	0	0	0	0	0	0	0
Score (D x 5)	0	0	0	0	0	0	0	0	0	0	0	0
CONJUNCTIVAE
A = Redness	1	1	0	0	1	1	0	0	1	1	0	0
B = Chemosis	1	1	0	0	1	0	0	0	1	0	0	0
C = Discharge	0	1	1	0	1	0	0	0	1	0	0	0
Score (A + B + C) x 2	4	6	2	0	6	2	0	0	6	2	0	0
Total Score	4	6	2	0	6	2	0	0	6	2	0	0

 

IPR=  Initial pain reaction

Table 2              Individual Total Scores and Group Mean Scores for Ocular Irritation

Rabbit Number and Sex	Individual Total Scores At:
	1 Hour	24 Hours	48 Hours	72 Hours
71360Male	4	6	2	0
71413Male	6	2	0	0
71414Male	6	2	0	0
Group Total	16	10	2	0
Group Mean Score	5.3	3.3	0.7	0.0

Table 3              Individual Bodyweights and Bodyweight Changes

Rabbit Number and Sex	Individual Bodyweight (kg)		Bodyweight Change (kg)
	Day 0	Day 3
71360Male	2.45	2.53	0.08
71413Male	2.75	2.82	0.07
71414Male	2.53	2.59	0.06

Interpretation of results:

other: mild irritant

Remarks:

Criteria used for interpretation of results: other: modified Kay and Calandra classification system

Conclusions:

The test item produced a maximum group mean score of 5.3 and was classified as a mild irritant (Class 4 on a 1 to 8 scale) to the rabbit eye according to a modified Kay and Calandra classification system.
The test item did not meet the criteria for classification according to the Classification, Labelling and Packaging Regulation or the Globally Harmonised Classification System.

Executive summary:

Introduction. The study was performed to assess the irritancy potential of the test item to the eye of the New Zealand White rabbit. The method was designed tobe compatible with thefollowing:

OECD Guidelines for the Testing of Chemicals No. 405 “Acute Eye Irritation/Corrosion” (adopted24 April 2002)

Method B5 Acute Toxicity (Eye Irritation) of CommissionRegulation (EC) No. 440/2008

Result. A single application of the test item to the non-irrigated eye of three rabbits produced minimal conjunctival irritation. Two treated eyes appeared normal at the 48‑Hour observation and one treated eye appeared normal at the 72‑Hour observation.

Conclusion. The test item produced a maximum group mean score of 5.3 and was classified as a mild irritant (Class 4 on a 1 to 8 scale) to the rabbit eye according to a modified Kay and Calandra classification system.

The test item did not meet the criteria for classification according to the Classification, Labelling and Packaging Regulation or the Globally Harmonised Classification System.

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed (not irritating)

Respiratory irritation

Endpoint conclusion

Endpoint conclusion:

no study available

Additional information

This summary is based upon two reliable (Klimisch 1) irritation studies (rabbit skin and rabbit eye) performed on Diurea 8 as provided but with slight moistening with water for the dermal study. In the dermal study, Diurea 8 produced a primary irritation index of 0.0 and no corrosive effects were noted. Diurea 8 did not meet the criteria for classification according to the Classification, Labelling and Packaging Regulation. When applied to rabbit eyes, Diurea 8 produced a maximum group mean score of 5.3 and did not meet the criteria for classification according to the Classification, Labelling and Packaging Regulation.

Justification for selection of skin irritation / corrosion endpoint:
Single study available

Justification for selection of eye irritation endpoint:
Single study available

Justification for classification or non-classification

Not classified as irritant to skin as the in vivo rabbit study was negative. Diurea 8 is also not classified as an irritant to the eye since the rabbit in vivo eye irritation study did not meet the criteria for classification according to the Classification, Labelling and Packaging Regulation.