Hexamethylene diacrylate

Endpoint summary

Description of key information

Skin (in vivo):

acc. OECD 404; rabbit, 4 h, semiocclussive: irritating to skin (Draize) (HRC, 1987)

comp. OECD 404; rabbit, 20 h, occlussive: irritating to skin (BASF, 1974)

Eye (in vivo):

comp. OECD 405; rabbit, 24 h, substance was not washed out: not irritating (Draize) (BASF, 1971)

rabbit, 24 h, substance was not washed out: not irritating (Draize) (TNO,1978)
rabbit, 24 h, substance was not washed out: not irritating (Draize) (Litton Bionetics, 1972)
rabbit, 24 h, substance was not washed out: Risk of serious damage to eyes (Draize) (Fraunhofer Gesellschaft, 1979)
rabbit, 24 h, substance was not washed out: Risk of serious damage to eyes (Draize) (TNO, 1978)

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

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

OECD Guideline 404 (Acute Dermal Irritation / Corrosion)

GLP compliance:

yes (incl. QA statement)

Species:

rabbit

Strain:

New Zealand White

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: Buckmasters, Henham, GB
- Age at study initiation: 11-13 weeks
- Weight at study initiation: 2.4 - 2.9 kg
- Housing: individually in metal cages with perforated floors
- Diet: SDS Standard Rabbit Diet, ad libitum
- Water: tap water, ad libitum
- Acclimation period: yes (not further specified)

ENVIRONMENTAL CONDITIONS
- Temperature: 19 °C
- Humidity: 30 - 70 %
- Air changes: approx. 19 per hour
- Photoperiod: 12 hrs dark / 12 hrs light

Type of coverage:

semiocclusive

Preparation of test site:

shaved

Vehicle:

unchanged (no vehicle)

Controls:

other: the untreated sites of the same animal served as control.

Amount / concentration applied:

0.5 ml undiluted test material

Duration of treatment / exposure:

4 hours

Observation period:

14 days

Number of animals:

3 animals

Details on study design:

Approximately 24 hours prior to application of the test substance, hair was removed with electric clippers from the dorso-lumbar region of each rabbit exposing an area of skin approximately 10 cm square.
A 0.5 ml aliquot of HDDA was applied under a 2.5 cm square gauze pad to one intact skin site on each animal.
Each treatment site was occluded with "Elastoplast" elastic adhesive dressing for a four hour period. The animals were not restrained during the exposure period and were returned to their cages.
At the end of the exposure period, the semi-occlusive dressing and gauze pad were removed and the treatment site was washed using water to remove any residual test substance.

Examination of the treated skin was made on Day 1 (i.e. approximately 30 minutes after removal of the patches) and on Days 2, 3 and 4. Additional observations were made on Days 5 through 14.

Grading and scoring of the dermal reactions were performed using the prescribed numerical scoring system according to Draize.

Irritation parameter:

erythema score

Basis:

animal #1

Time point:

24/48/72 h

Score:

2

Max. score:

4

Reversibility:

not fully reversible within: 14 days

Remarks on result:

other: desquamation was seen on days 9 through 14

Irritation parameter:

erythema score

Basis:

animal #2

Time point:

24/48/72 h

Score:

2

Max. score:

4

Reversibility:

not fully reversible within: 14 days

Remarks on result:

other: desquamation was seen on days 9 through 14

Irritation parameter:

erythema score

Basis:

animal #3

Time point:

24/48/72 h

Score:

2

Max. score:

4

Reversibility:

not fully reversible within: 14 days

Remarks on result:

other: desquamation was seen on days 9 through 14

Irritation parameter:

edema score

Basis:

animal #1

Time point:

24/48/72 h

Score:

2.67

Max. score:

4

Reversibility:

fully reversible within: 14 days

Irritation parameter:

edema score

Basis:

animal #2

Time point:

24/48/72 h

Score:

2.67

Max. score:

4

Reversibility:

not fully reversible within: 14 days

Irritation parameter:

edema score

Basis:

animal #3

Time point:

24/48/72 h

Score:

2.67

Max. score:

4

Reversibility:

not fully reversible within: 14 days

Irritant / corrosive response data:

The single semi-occlusive application of HDDA to intact rabbit skin for four hours elicited persistent well-defined to moderate dermal irritation.

Table 1: Erythema and edema scores of the individual animals from day 1 to day 14

	Animal 1		Animal 2		Animal 3
Day	Erythema	Edema	Erythema	Edema	Erythema	Edema
1	2	3	2	3	2	3
2	2	3	2	3	2	3
3	2	2	2	2	2	2
4	2	3	2	2	2	2
5	2	2	2	2	2	2
6	2	2	2	2	2	2
7	2	1	2	1	2	2
8	2	1	2	1	2	2
9	2	2	2	2	2	2
10	2	2	2	2	2	2
11	2	1	2	2	2	2
12	2	1	2	1	2	1
13	1	1	2	1	1	1
14	1	0	1	1	1	1

Conclusions:

Under the conditions of the test, the test substance fulfils the requirements to be classified according to GHS (Irritant category 2) criteria.

Endpoint conclusion

Endpoint conclusion:

adverse effect observed (irritating)

Eye irritation

Link to relevant study records

Reference

Reference 1

Endpoint:

eye irritation: in vivo

Type of information:

experimental study

Adequacy of study:

weight of evidence

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: Meets generally accepted scientific principles.

Qualifier:

equivalent or similar to guideline

Guideline:

OECD Guideline 405 (Acute Eye Irritation / Corrosion)

Deviations:

yes

Remarks:

[volume of 0.05 ml applied (OECD: volume of 0.1 ml); 2 animals were used (OECD: 3); observation period was 8 days (OECD: 21); examination using fluorescein (OECD: no use of fluorescein)]

Principles of method if other than guideline:

BASF-TEST:
Before OECD guideline 405 was established, eye irritation was tested using an internal method. White Vienna rabbits were used. Usually approximately 50 µl of the test substance were applied to the conjunctival sac of one eye of each of 2 animals. The non- or saline- treated eye served as control. In studies with solids, talcum powder was used as control. The animals were observed several times on the treatment day and up to 8 days afterwards, and findings were recorded on working days. The eyes were not washed out after 24 h as specified in OECD Guideline 405.

GLP compliance:

no

Remarks:

; GLP was not compulsory at the time the study was conducted

Species:

rabbit

Strain:

Vienna White

Details on test animals or tissues and environmental conditions:

TEST ANIMALS
- Weight at study initiation: 3.09 kg, 2.81 kg

Vehicle:

unchanged (no vehicle)

Controls:

other: the second eye of the same rabbit was treated with 50 µl NaCl saline

Amount / concentration applied:

undiluted
Amount applied: 0.05 ml

Duration of treatment / exposure:

24 h; the substance was not washed out

Observation period (in vivo):

8 days

Number of animals or in vitro replicates:

2 animals, 1 male and 1 female

Details on study design:

50 µl of the undiluted test substance was applied to the right conjuntival sac of one male and one female Vienna White rabbit. The left eye treated with physiological saline served as a control. The substance was not washed out.
Ocular reactions were recorded 10 min, 1, 3 and 24 hours, as well as 2, 5, 7 and 8 days after instillation using a BASF-scoring system, which is convertible into the current OECD Draize scheme. For the evaluation, the BASF scores given in the raw data were converted to Draize scores. The reading time points used for assessment were 24, 48 and 72 hours after application. At day 8, the eyes were additionally examined by using fluorescein.

Irritation parameter:

conjunctivae score

Basis:

animal #1

Time point:

24/48 h

Score:

1

Max. score:

3

Reversibility:

fully reversible within: 7 days

Irritation parameter:

conjunctivae score

Basis:

animal #2

Time point:

24/48 h

Score:

1

Max. score:

3

Reversibility:

fully reversible within: 7 days

Irritation parameter:

cornea opacity score

Basis:

animal #1

Time point:

24/48 h

Score:

0

Max. score:

4

Irritation parameter:

cornea opacity score

Basis:

animal #2

Time point:

24/48 h

Score:

0

Max. score:

4

Irritation parameter:

iris score

Basis:

animal #1

Time point:

24/48 h

Score:

0

Max. score:

2

Irritation parameter:

iris score

Basis:

animal #2

Time point:

24/48 h

Score:

0

Max. score:

2

Irritation parameter:

chemosis score

Basis:

animal #1

Time point:

24/48 h

Score:

0

Max. score:

4

Irritation parameter:

chemosis score

Basis:

animal #2

Time point:

24/48 h

Score:

0

Max. score:

4

Other effects:

Details on irritation response:
In both tested animals secretion was observed in the substance-treated eye up to 3 hours after instillation of the test substance.
Both animals showed slight redness of conjunctivae during the first 5 days (see table 1). However, this effect was fully reversible within 7 days. Cornea and iris were inconspicious.
The left eye of both animals which was treated with saline and served as control showed no effects.

Table 1: Eye irritation parameters; the scores of the BASF study were converted according to the method of Draize

Reading time point	Animal 1, treated eye (right)
	Cornea score	Iris score	Conjunctiva Redness	Conjunctiva Chemosis	Additional findings
10 min	0	0	1	0	secretion
1 h	0	0	1	0	secretion
3 h	0	0	1	0	secretion
24 h	0	0	1	0
48 h	0	0	1	0
5 d	0	0	1	0
7 d	0	0	0	0
8 d	0	0	0	0
Reading time point	Animal 2, treated eye (right)
	Cornea	Iris	Conjunctiva Redness	Conjunctiva Chemosis	Additional findings
10 min	0	0	1	0	secretion
1 h	0	0	1	0	secretion
3 h	0	0	1	0	secretion
24 h	0	0	1	0
48 h	0	0	1	0
5 d	0	0	1	0
7 d	0	0	0	0
8 d	0	0	0	0

Conclusions:

Under the conditions of the test, the test material does not fulfil the requirements to be classified according to EU (as conjunctivae score < 2.5) or GHS (as conjunctivae score < 2) criteria.

Reference 2

Endpoint:

eye irritation: in vivo

Type of information:

experimental study

Adequacy of study:

weight of evidence

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: Meets generally accepted scientific principles.

Qualifier:

equivalent or similar to guideline

Guideline:

OECD Guideline 405 (Acute Eye Irritation / Corrosion)

Principles of method if other than guideline:

A Draize test was conducted. Eye irritancy was studied by direct application of the test material into the conjunctival sac of each test animal.

GLP compliance:

no

Remarks:

; GLP was not compulsory at the time the study was conducted.

Species:

rabbit

Strain:

New Zealand White

Details on test animals or tissues and environmental conditions:

TEST ANIMALS
- Average weight at study initiation: 1.85 kg

Vehicle:

unchanged (no vehicle)

Controls:

other: the untreated eye of the same animal served as control

Amount / concentration applied:

With an assistent holding the animal and forming a pouch of the lower eyelid, a sample of 0.1 ml of the test material was delivered directly into the conjunctival sac.

Duration of treatment / exposure:

The substnce was not washed out.

Observation period (in vivo):

72 hours

Number of animals or in vitro replicates:

6 animals were used.

Details on study design:

The chosen eye (usually left) of each rabbit was stained with fluorescein and examined with the aid of magnification and fluorescent lighting to ascertain that it was clear of any lesions before application of the test material. With an assistant holding the animal and forming a pouch of the lower eyelid, a sample of 0.1 ml of the material was delivered directly into the conjunctival sac. After delivery of the material, the eyelid was released and the lids gently pressed together for a few seconds. Following this, the animal was released and returned to his cage until time for scheduled observations. Washing was not performed. Thus, this constitutes the most severe form of the Draize test. The opposite eye remained untreated and served as a control. One hour after the initial application, each eye was examined. The examination was repeated at four hours, at 24 hours, at 48 hours, and at 72 hours.

Irritation parameter:

cornea opacity score

Basis:

mean

Remarks:

of all 6 animals

Time point:

24/48/72 h

Score:

0

Max. score:

4

Reversibility:

other: not applicable

Irritation parameter:

iris score

Basis:

mean

Remarks:

of all 6 animals

Time point:

24/48/72 h

Score:

0

Max. score:

2

Reversibility:

other: not applicable

Irritation parameter:

chemosis score

Basis:

mean

Remarks:

of all 6 animals

Time point:

24/48/72 h

Score:

0

Max. score:

4

Reversibility:

other: not applicable

Irritation parameter:

conjunctivae score

Basis:

mean

Remarks:

of 5 animals

Time point:

24/48/72 h

Score:

0.33

Max. score:

3

Reversibility:

fully reversible within: 48 h

Irritation parameter:

conjunctivae score

Basis:

animal #6

Time point:

24/48/72 h

Score:

0

Max. score:

3

Reversibility:

other: not applicable

Table 1: Eye irritation parameters; scores according to the method of Draize
Reading time point	Animal 1, treated eye
	Cornea score	Iris score	Conjunctivae score	Chemosis	Additional findings
24 h	0	0	1	0
48 h	0	0	0	0
72 h	0	0	0	0
Reading time point	Animal 2, treated eye
	Cornea score	Iris score	Conjunctivae score	Chemosis	Additional findings
24 h	0	0	1	0
48 h	0	0	0	0
72 h	0	0	0	0
Reading time point	Animal 3, treated eye
	Cornea score	Iris score	Conjunctivae score	Chemosis	Additional findings
24 h	0	0	1	0
48 h	0	0	0	0
72 h	0	0	0	0
Reading time point	Animal 4, treated eye
	Cornea score	Iris score	Conjunctivae score	Chemosis	Additional findings
24 h	0	0	1	0
48 h	0	0	0	0
72 h	0	0	0	0
Reading time point	Animal 5, treated eye
	Cornea score	Iris score	Conjunctivae score	Chemosis	Additional findings
24 h	0	0	1	0
48 h	0	0	0	0
72 h	0	0	0	0
Reading time point	Animal 6, treated eye
	Cornea score	Iris score	Conjunctivae score	Chemosis	Additional findings
24 h	0	0	0	0
48 h	0	0	0	0
72 h	0	0	0	0

Conclusions:

Under the conditions of the test, the test material does not fulfil the requirements to be classified according to GHS criteria.

Reference 3

Endpoint:

eye irritation: in vivo

Type of information:

experimental study

Adequacy of study:

weight of evidence

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

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

Qualifier:

according to guideline

Guideline:

other: Federal Register 28 (119), 5582, 1963

Principles of method if other than guideline:

New Zealand White rabbits were used. Approximately 100 µl of the test substance was applied to the conjunctival sac of one eye of each of 6 animals.The non- or saline- treated eye served as control. In studies with solids, talcum powder was used as control. The animals were observed after 1 h, 24 h, 48 h, 72 h and 7 days after instillation of the test material.
The eyes were not washed out after 24 h as specified in OECD Guideline 405. However, at the time the study was conducted, this requirement was not compulsory. This fact could be critical for solids which thus remained on the cornea for several days, causing mechanical damage. Probably, this would have been less severe if it had been washed out after 1 day.

GLP compliance:

no

Remarks:

; GLP was not compulsory at the time the study was conducted

Species:

rabbit

Strain:

New Zealand White

Details on test animals or tissues and environmental conditions:

TEST ANIMALS
- Housing: individual; 1 animal per cage
- The animals did not receive any hay or other extraneous material that might enter the eyes

Vehicle:

unchanged (no vehicle)

Controls:

other: the second eye of the same rabbit served as control and was not treated

Amount / concentration applied:

undiluted
Amount applied: 0.1 ml

Duration of treatment / exposure:

24 h; The substance was not washed out

Observation period (in vivo):

7 days

Number of animals or in vitro replicates:

6

Details on study design:

100 µl of the undiluted test substance was applied to the conjuntival sac of the right eye of each animal. The second eye was not treated and served as a control. The substance was not rinsed or washed out.
Ocular reactions were recorded 1 h, 24 h, 48 h, 72 h and 8 days after instillation and were evaluated using Draize scores. The reading time points used for assessment were 24, 48 and 72 hours after application.

Irritation parameter:

cornea opacity score

Basis:

mean

Remarks:

for each animal

Time point:

24/48/72 h

Score:

0

Max. score:

4

Remarks on result:

other: in no animal effects were seen

Irritation parameter:

iris score

Basis:

mean

Remarks:

for each animal

Time point:

24/48/72 h

Score:

0

Max. score:

2

Remarks on result:

other: in no animal effects were seen

Irritation parameter:

chemosis score

Basis:

mean

Remarks:

for each animal

Time point:

24/48/72 h

Score:

0

Max. score:

4

Remarks on result:

other: effects were observed after 1 hour only in 4 of 6 animals

Irritation parameter:

conjunctivae score

Basis:

animal #1

Time point:

24/48/72 h

Score:

0.33

Max. score:

3

Reversibility:

fully reversible within: 48 h

Irritation parameter:

conjunctivae score

Basis:

animal #2

Time point:

24/48/72 h

Score:

0

Max. score:

3

Irritation parameter:

conjunctivae score

Basis:

animal #3

Time point:

24/48/72 h

Score:

0.33

Max. score:

3

Reversibility:

fully reversible within: 48 hours

Irritation parameter:

conjunctivae score

Basis:

animal #4

Time point:

24/48/72 h

Score:

0.33

Max. score:

3

Reversibility:

fully reversible within: 48 hours

Irritation parameter:

conjunctivae score

Basis:

animal #5

Time point:

24/48/72 h

Score:

0.33

Max. score:

3

Reversibility:

fully reversible within: 48 hours

Irritation parameter:

conjunctivae score

Basis:

animal #6

Time point:

24/48/72 h

Score:

1

Max. score:

3

Reversibility:

fully reversible within: 7 days

Other effects:

Details on irritation response:
During the first day after instillation slight redness of the conjunctivae was observed in all six rabbits; chemosis was only seen after one hour in 4 of 6 animals. Redness of the conjunctivae was fully reversible in all animals within 7 days.
Cornea and iris were inconspicuous. 3 animals showed discharge at 1 hour after application.

Table 1: Eye irritation parameters
Reading time point	Animal 1, treated eye (right)
	Cornea score	Iris score	Conjunctivae score	Chemosis	Additional findings
1 h	0	0	1	1	discharge
24 h	0	0	1	0
48 h	0	0	0	0
72 h	0	0	0	0
7 d	0	0	0	0
Reading time point	Animal 2, treated eye (right)
	Cornea score	Iris score	Conjunctivae score	Chemosis	Additional findings
1 h	0	0	1	1
24 h	0	0	0	0
48 h	0	0	0	0
72 h	0	0	0	0
7 d	0	0	0	0
Reading time point	Animal 3, treated eye (right)
	Cornea score	Iris score	Conjunctivae score	Chemosis	Additional findings
1 h	0	0	1	0
24 h	0	0	1	0
48 h	0	0	0	0
72 h	0	0	0	0
7 d	0	0	0	0
Reading time point	Animal 4, treated eye (right)
	Cornea score	Iris score	Conjunctivae score	Chemosis	Additional findings
1 h	0	0	1	1	discharge
24 h	0	0	1	0
48 h	0	0	0	0
72 h	0	0	0	0
7 d	0	0	0	0
Reading time point	Animal 5, treated eye (right)
	Cornea score	Iris score	Conjunctivae score	Chemosis	Additional findings
1 h	0	0	1	0
24 h	0	0	1	0
48 h	0	0	0	0
72 h	0	0	0	0
7 d	0	0	0	0
Reading time point	Animal 6, treated eye (right)
	Cornea score	Iris score	Conjunctivae score	Chemosis	Additional findings
1 h	0	0	1	1	discharge
24 h	0	0	1	0
48 h	0	0	1	0
72 h	0	0	1	0
7 d	0	0	0	0

Conclusions:

Under the conditions of the test, the test material will not be classified according to GHS criteria.

Reference 4

Endpoint:

eye irritation: in vivo

Type of information:

experimental study

Adequacy of study:

weight of evidence

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

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

Qualifier:

according to guideline

Guideline:

other: Code of Federal Regulations, Title 16, Section 1500.42

Principles of method if other than guideline:

New Zealand White rabbits were used. Approximately 100 µl of the test substance was applied to the conjunctival sac of one eye of each of 6 animals. The non- or saline- treated eye served as control. In studies with solids, talcum powder was used as control. The animals were observed after 24 h, 48 h, 72 h and after 8 days following application.
The eyes were not washed out after 24 h as optionally recommended in OECD Guideline 405. However, at the time the study was conducted, this requirement was not compulsory. This fact could be critical for solids which thus remained on the cornea for several days, causing mechanical damage. Probably, this would have been less severe if it had been washed out after 1 day.

GLP compliance:

no

Remarks:

; GLP was not compulsory at the time the study was conducted

Species:

rabbit

Strain:

New Zealand White

Details on test animals or tissues and environmental conditions:

TEST ANIMALS
- Source: W. Ostrop, Meerbusch
- Weight at study initiation: 2.0 kg average weight
- Housing: individual; 1 animal per cage
- Diet: Mümmel Z (ssniff, Soest), ad libitum
- Water: ad libitum
- Acclimation period: 4-6 days


ENVIRONMENTAL CONDITIONS
- Temperature (°C): 16-18 °C
- Humidity (%): 40 %
- Photoperiod: daylight rhythm

Vehicle:

unchanged (no vehicle)

Controls:

other: the second eye of the same rabbit served as control and was not treated

Amount / concentration applied:

undiluted
Amount applied: 0.1 ml

Duration of treatment / exposure:

24 h; the substance was not washed out

Observation period (in vivo):

8 days

Number of animals or in vitro replicates:

6

Details on study design:

100 µl of the undiluted test substance was applied to the conjuntival sac of the right eye of each animal. The left eye was not treated and served as a control. The substance was not rinsed or washed out.
Ocular reactions were recorded 24 h, 48 h, 72 h and 8 days after instillation and were evaluated using Draize scores. The reading time points used for assessment were 24, 48 and 72 hours after application. And ophthalmoscope was used and fluorescein was used on day 8.

Irritation parameter:

cornea opacity score

Basis:

animal #1

Time point:

24/48/72 h

Score:

2

Max. score:

4

Reversibility:

not fully reversible within: 8 days

Irritation parameter:

cornea opacity score

Basis:

animal #2

Time point:

24/48/72 h

Score:

1

Max. score:

4

Reversibility:

fully reversible within: 8 days

Irritation parameter:

cornea opacity score

Basis:

animal #4

Time point:

24/48/72 h

Score:

0

Max. score:

4

Irritation parameter:

cornea opacity score

Basis:

animal #5

Time point:

24/48/72 h

Score:

1

Max. score:

4

Reversibility:

fully reversible within: 8 days

Irritation parameter:

iris score

Basis:

animal #1

Time point:

24/48/72 h

Score:

1

Max. score:

2

Reversibility:

not fully reversible within: 8 days

Irritation parameter:

iris score

Basis:

animal #2

Time point:

24/48/72 h

Score:

0

Max. score:

2

Irritation parameter:

iris score

Basis:

animal #4

Time point:

24/48/72 h

Score:

0

Max. score:

2

Irritation parameter:

iris score

Basis:

animal #5

Time point:

24/48/72 h

Score:

0.67

Max. score:

2

Reversibility:

fully reversible within: 8 days

Irritation parameter:

conjunctivae score

Basis:

animal #1

Time point:

24/48/72 h

Score:

2.33

Max. score:

3

Reversibility:

not fully reversible within: 8 days

Irritation parameter:

conjunctivae score

Basis:

animal #2

Time point:

24/48/72 h

Score:

3

Max. score:

3

Reversibility:

not fully reversible within: 8 days

Irritation parameter:

conjunctivae score

Basis:

animal #4

Time point:

24/48/72 h

Score:

2

Max. score:

3

Reversibility:

not fully reversible within: 8 days

Irritation parameter:

conjunctivae score

Basis:

animal #5

Time point:

24/48/72 h

Score:

3

Max. score:

3

Reversibility:

not fully reversible within: 8 days

Irritation parameter:

chemosis score

Basis:

animal #1

Time point:

24/48/72 h

Score:

2.33

Max. score:

4

Reversibility:

not fully reversible within: 8 days

Irritation parameter:

chemosis score

Basis:

animal #2

Time point:

24/48/72 h

Score:

3.66

Max. score:

4

Reversibility:

not fully reversible within: 8 days

Irritation parameter:

chemosis score

Basis:

animal #4

Time point:

24/48/72 h

Score:

2.33

Max. score:

4

Reversibility:

not fully reversible within: 8 days

Irritation parameter:

chemosis score

Basis:

animal #5

Time point:

24/48/72 h

Score:

3.66

Max. score:

4

Reversibility:

not fully reversible within: 8 days

Irritation parameter:

other: cornea, iris, conjunctiva and chemosis score

Basis:

animal: #3 and #6 each

Time point:

24/48/72 h

Score:

0

Max. score:

4

Remarks on result:

other: No effects were seen in these 2 animals.

Other effects:

During the first day after instillation slight corneal opacity was observed in three out of six rabbits, slight iritis in one and lesions of the conjunctivae
in four rabbits. In 4 animals corneal opacity, iritis, conjunctival redness, chemosis and sometimes secretion were reported. Effects only in part were seen to be reversible within 8 days.
The remaining 2 rabbits (animal #3 and animal #6) were free of symptoms during the whole observation period.

Table 1: Eye irritation parameters; scores according to the method of Draize
Reading time point	Animal 1, treated eye (right)
	Cornea score	Iris score	Conjunctivae score	Chemosis	Additional findings
24 h	2	1	3	3	secretion
48 h	2	1	2	3	secretion
72 h	2	1	2	1
8 d	1	1	2	3
Reading time point	Animal 2, treated eye (right)
	Cornea score	Iris score	Conjunctivae score	Chemosis	Additional findings
24 h	1	0	3	3
48 h	1	0	3	4	secretion
72 h	1	0	3	4	secretion
8 d	0	0	2	4	secretion
Reading time point	Animal 3, treated eye (right)
	Cornea score	Iris score	Conjunctivae score	Chemosis	Additional findings
24 h	0	0	0	0
48 h	0	0	0	0
72 h	0	0	0	0
8 d	0	0	0	0
Reading time point	Animal 4, treated eye (right)
	Cornea score	Iris score	Conjunctivae score	Chemosis	Additional findings
24 h	0	0	2	3
48 h	0	0	2	2
72 h	0	0	2	2	secretion
8 d	0	0	1	2	secretion
Reading time point	Animal 5, treated eye (right)
	Cornea score	Iris score	Conjunctivae score	Chemosis	Additional findings
24 h	1	0	3	3
48 h	1	1	3	4	secretion
72 h	1	1	3	4	secretion
8 d	0	0	2	3
Reading time point	Animal 6, treated eye (right)
	Cornea score	Iris score	Conjunctivae score	Chemosis	Additional findings
24 h	0	0	0	0
48 h	0	0	0	0
72 h	0	0	0	0
8 d	0	0	0	0

Conclusions:

According to GHS criteria, the test material has to be classified as Category 1 "Irritating to eye".

Reference 5

Endpoint:

eye irritation: in vivo

Type of information:

experimental study

Adequacy of study:

weight of evidence

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

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

Qualifier:

according to guideline

Guideline:

other: Fed. Reg. 28 (119), 5582, 1963

Deviations:

yes

Remarks:

Eyes, were not washed after 24 h

Principles of method if other than guideline:

New Zealand White rabbits were used. Approximately 100 µl of the test substance were applied to each conjunctival sac of one eye of 6 animals.The non- or saline- treated eyes served as control. In studies with solids, talcum powder was used as control. The animals were observed after 1 h, 24 h, 48 h, 72 h and 7 days after instillation of the test material.
The eyes were not washed out after 24 h as specified in OECD Guideline 405. However, at the time the study was conducted, this requirement was not compulsory. This fact could be critical for solids which thus remained on the cornea for several days, causing mechanical damage. Probably, this would have been less severe if it had been washed out after 1 day.

GLP compliance:

no

Remarks:

; GLP was not compulsory at the time the study was conducted

Species:

rabbit

Strain:

New Zealand White

Details on test animals or tissues and environmental conditions:

TEST ANIMALS
- Housing: individual; 1 animal per cage
- The animals do not receive any hay or other extraneous material that might enter the eyes

Vehicle:

unchanged (no vehicle)

Controls:

other: the second eye of the same rabbit served as control and was not treated

Amount / concentration applied:

undiluted
Amount applied: 0.1 ml

Duration of treatment / exposure:

24 h; The substance was not washed out

Observation period (in vivo):

7 days

Number of animals or in vitro replicates:

6

Details on study design:

100 µl of the undiluted test substance was applied to the conjuntival sac of the right eye of each animal. The second eye was not treated and served as a control. The substance was not rinsed or washed out.
Ocular reactions were recorded 1 h, 24 h, 48 h, 72 h and 8 days after instillation and were evaluated using Draize scores. The reading time points used for assessment were 24, 48 and 72 hours after application.

Irritation parameter:

cornea opacity score

Basis:

mean

Remarks:

for all animals

Time point:

24/48/72 h

Score:

0.78

Max. score:

4

Reversibility:

other: in 2 animals no reversibility was seen after 7 days

Remarks on result:

other: animal #1: 0; #2: 1; #3: 1.33; #4: 1.33; #5: 1.0; #6: 0

Irritation parameter:

iris score

Basis:

mean

Remarks:

for all animals

Time point:

24/48/72 h

Score:

0.5

Max. score:

2

Reversibility:

other: in 1 animal no reversibility was seen after 7 days

Remarks on result:

other: animal #1: 0; #2: 0.67; #3: 0.67; #4: 0.67; #5: 1.0; #6: 0

Irritation parameter:

conjunctivae score

Basis:

mean

Remarks:

for all animals

Time point:

24/48/72 h

Score:

1.22

Max. score:

3

Reversibility:

other: in 2 animals no reversibility was seen after 7 days

Remarks on result:

other: animal #1: 1.0; #2: 1.0; #3: 1.33; #4: 1.66; #5: 1.33; #6: 1.0

Irritation parameter:

chemosis score

Basis:

mean

Remarks:

for all animals

Time point:

24/48/72 h

Score:

1.22

Max. score:

4

Reversibility:

other: in 2 animals no reversibility was seen after 7 days

Remarks on result:

other: animal #1: 0; #2: 0.67; #3: 1.66; #4: 2.33; #5: 1.33; #6: 0.33

Other effects:

During the first day after instillation slight corneal opacity was observed in four out of six rabbits, slight iritis in two out of six rabbits and slight or moderate redness/chemosis of the conjunctivae in all six rabbits.
In the course of the seven-day observation period some recovery occurred. At the end of this period slight or moderate corneal opacity was still observed in two rabbits, slight iritis in one rabbit and slight or moderate redness/chemosis of the conjunctivae in two rabbits.
In addition, increased eye discharge, in some cases with moistening of the lids and hairs just adjacent to lids was seen in all animals. In one case discharge lasted up to day 7.

Table 1: Eye irritation parameters; scores according to the method of Draize
Reading time point	Animal 1, treated eye (right)
	Cornea score	Iris score	Conjunctivae score	Chemosis	Additional findings
1 h	0	0	1	2	discharge
24 h	0	0	1	0
48 h	0	0	1	0
72 h	0	0	1	0
7 d	0	0	0	0
Reading time point	Animal 2, treated eye (right)
	Cornea score	Iris score	Conjunctivae score	Chemosis	Additional findings
1 h	0	0	1	1	discharge
24 h	1	1	1	1	discharge
48 h	1	1	1	1	discharge
72 h	1	0	1	0
7 d	0	0	0	0
Reading time point	Animal 3, treated eye (right)
	Cornea score	Iris score	Conjunctivae score	Chemosis	Additional findings
1 h	0	0	1	2	discharge
24 h	1	0	1	1	discharge
48 h	1	1	2	2	discharge
72 h	2	1	1	2	discharge
7 d	2	1	1	2	discharge
Reading time point	Animal 4, treated eye (right)
	Cornea score	Iris score	Conjunctivae score	Chemosis	Additional findings
1 h	0	0	1	2	discharge
24 h	1	0	2	2	discharge
48 h	1	1	2	3	discharge
72 h	2	1	1	2	discharge
7 d	1	0	0	0
Reading time point	Animal 5, treated eye (right)
	Cornea score	Iris score	Conjunctivae score	Chemosis	Additional findings
1 h	0	0	1	2	discharge
24 h	1	1	1	1	discharge
48 h	1	1	2	2	discharge
72 h	1	1	1	1
7 d	0	0	0	0
Reading time point	Animal 6, treated eye (right)
	Cornea score	Iris score	Conjunctivae score	Chemosis	Additional findings
1 h	0	0	1	1	discharge
24 h	0	0	1	0	discharge
48 h	0	0	1	0
72 h	0	0	1	1
7 d	0	0	1	1

Conclusions:

According to GHS criteria, the test material has to be classified as Category 1, as the symptoms observed were not fully reversible after 7 days.

Endpoint conclusion

Endpoint conclusion:

adverse effect observed (irritating)

Respiratory irritation

Endpoint conclusion

Endpoint conclusion:

no study available

Additional information

There are valid in vivo data available for the assessment of the skin and eye irritation potential of 1,6-hexanedioldiacrylate.

 

Skin

In a skin irritation test, according to OECD guideline 404, a 0.5 ml aliquot of HDDA was applied under a 2.5 cm square gauze pad to one intact skin site on each of three animals. The test material was applied under semiocclusive conditions for 4 hours. Grading and scoring of the dermal reactions were performed using the scoring system according to Draize. The single semi-occlusive application of HDDA to intact rabbit skin for four hours elicited persistent well-defined to moderate dermal irritation. Very slight to well-defined erythema with or without very slight to moderate edema was seen in all three animals throughout the study. Desquamation was seen in all animals from days 9 through 14 (HRC, 1987).

A further skin irritation test was performed with two White Vienna rabbits (comp. OECD 404). A 20-hour occlusive exposure to ca. 1 ml of the undiluted test substance produced a moderate erythema exceeding application area and edema (in some cases brownish) during day 1 to day 4 in both treated animals. The mean score for the 24, 48 and 72 h reading for erythema was 2.5, for edema it was 2.83, respectively. At the end of the observation period (day 8), erythema (grade 2) was still observed in one animal and scaling was seen in two animals (BASF, 1974).

In several further studies which were predominantly conducted within the framework of a ring study, rabbits were exposed to the unchanged test substance for 24 h under occlusive conditions, according to the method of Draize. The results, determined by different testing laboratories, showed a broad variation of the individual irritating scores obtained. No differences in skin irritation were seen, when different technical products were tested in comparison with distilled hexanedioldiacrylate in the same species under the same experimental conditions. Despite of the varying irritating scores obtained in the individual studies, a clear skin irritation potential for 1,6-hexanedioldiacrylate was demonstrated in all studies (BASF, 1974; Hazleton Laboratories, 1979; IFREB, 1979; BASF,1979; IFREB, 1979; INBIFO, 1979; Fraunhofer Gesellschaft,1979; TNO, 1979; LPT, 1979; IBR, 1979; Covance 1997 and 1999; Gelbke, 1979).

The results obtained under occlusive conditions should all be considered as overpredictive due to the harsh test conditions if compared to actual guideline recommendations (4 h under semiocclusive conditions).

 

Eye

No signs of eye irritation were seen in a Draize test, which was performed with two White Vienna rabbits (comp. OECD 405). Eyes were left unwashed after application of 0.05 ml 1,6-hexanedioldiacrylate and the animals were observed for 8 days. The mean score for conjunctivae redness for the 24, 48 and 72 h reading was 1.0 and was fully reversible in 2/2 animals within 7 days. Scores for iritis, cornea opacity and conjunctivae chemosis were 0 at any time point (BASF, 1974).

This non-irritating result was confirmed in two further Draize tests, which were conducted with 0.1 ml of 1,6-hexanedioldiacrylate: Also here, no signs of eye irritation were seen after application of the test substance into one eye of 6 New Zealand White rabbits in each study. The eyes were left unwashed after application of the substance and the animals were observed for 7 days. Until 24 hours after instillation of the test material, slight redness and chemosis of the conjunctivae was observed, but all effects were fully reversible in all animals at the latest of 7 days (TNO, 1978; Litton Bionetics, 1972).

There are two further studies available which clearly provided signs of serious eye irritation. However, these results should be considered as overpredictive due to the harsh test conditions if compared to actual guideline recommendations (substance was not washed out after 24 hours, observation period was completed after 8 days). Additionally, no information was available in terms of the amount and definition of impurities within the test material. Nevertheless, the test substance was legally classified as Category 2 according to GHS-criteria (1272/2008/EC) as a precautionary measurement:

The first study, clearly showing signs of serious eye irritation, was conducted with 6 New Zealand White rabbits; the eyes were left unwashed after application of 0.1 ml 1,6-hexanedioldiacrylate and the animals were observed for 8 days. During the first day after instillation slight corneal opacity was observed in three out of six rabbits, slight iritis was seen in one and lesions of the conjunctivae were seen in four rabbits. In 4 animals corneal opacity, iritis, conjunctival redness, chemosis and sometimes secretion were reported during the study period. Effects were seen to be reversible only in part within 8 days. The remaining 2 rabbits were free of symptoms during the whole observation period (Fraunhofer Gesellschaft, 1979).

The result of the second study also clearly indicates a severe eye irritating potential of 1,6-hexanedioldiacrylate. 0.1 ml 1,6-Hexanedioldiacrylate was applied to one eye of each of 6 New Zealand White rabbits, the eyes were also left unwashed after application and the animals were observed for 7 days. During the first day after instillation slight corneal opacity was observed in 4/6 rabbits, slight iritis 2/6 rabbits and slight or moderate redness/chemosis of the conjunctivae in all six rabbits. In the course of the seven-day observation period some recovery occurred. At the end of this period slight or moderate corneal opacity was still observed in two rabbits, slight iritis in one rabbit and slight or moderate redness/chemosis of the conjunctivae in two rabbits. In addition, increased eye discharge, in some cases with moistening of the lids and hairs just adjacent to lids was seen in all animals. In one case discharge lasted up to day (TNO, 1978). 

Justification for classification or non-classification

Skin

Due to the skin irritation effects observed, 1,6-hexanedioldiacrylate fulfills the requirements to be classified as skin irritant according to (1272/2008/EC) as Category 2.

 

Eye

For the eye, the data currently available present an unequivocal result:

On the one hand, in three studies no or only slight effects were observed in the eyes of the tested animals, which were all fully reversible after an observation period of 7 or, in one case, 8 days.

On the other hand, severe eye irritation effects were observed on corneal opacity, iritis, conjunctival redness and chemosis in two studies, which would -at first glance- justify a category 1 classification. However, due to the harsh test conditions applied, compared to actual guideline recommendations, the results obtained are considered to be overpredictive, as the substance was not washed out after 24 hours and the observation periods were completed after only 8 days. Additionally, no information was available in terms of the amount and definition of impurities within the test material. Considering the whole observation period from the moment of application until observation day 8, a tendency of decreasing effects in the eyes of the animals can be seen with preceding time (which presumably would have been fully reversible after an observation period of 21 days). Additionally, the effects observed would presumably have been less severe if 1,6-hexanedioldiacrylate had been washed out after 24 hours. Nevertheless it was demonstrated in these studies that 1,6-hexanedioldiacrylate holds a distinct irritating potential to the eye.

Therefore, taken the results together, on the basis of an weight of evidence approach and as a precautionary measure, 1,6-hexanedioldiacrylate has to be classified as eye irritant according to GHS-criteria (1272/2008/EC) as Category 2.

 

Respiratory system

Actually, there are no data available for a classification according to this endpoint.