Registration Dossier

Under the test conditions, Reaction mass of 3,6-dihydro-4-methyl-2-phenyl-2H-pyran and tetrahydro-4-methylene-2-phenyl-2H-pyran is not classified as irritating to skin or eyes according to the Directive 67/548/EEC and the CLP Regulation.

Reference

Endpoint:

skin irritation: in vivo

Type of information:

experimental study

Adequacy of study:

key study

Study period:

1981

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: see 'Remark'

Remarks:

Non-GLP study conducted similarly to OECD Guideline 404 with deviations: no data about purity and no certificate of analysis of the test substance; no details on environmental conditions; occlusive patches applied for 24 h and scored at 24 and 72 h after application; observations not followed until the reversibility of the effects

Reason / purpose for cross-reference:

reference to same study

Reason / purpose for cross-reference:

reference to other study

Qualifier:

equivalent or similar to guideline

Guideline:

OECD Guideline 404 (Acute Dermal Irritation / Corrosion)

Deviations:

yes

Remarks:

no GLP statement; no data about purity; no certificate of analysis of test substance; no details on environmental conditions; occlusive patches applied for 24 h and scored at 24 and 72 h after application; observations not followed until the reversibility

Principles of method if other than guideline:

Not applicable

GLP compliance:

yes

Species:

rabbit

Strain:

New Zealand White

Details on test animals or test system and environmental conditions:

- Age at study initiation: Adult

Type of coverage:

occlusive

Preparation of test site:

other: intact or abraded skin

Vehicle:

unchanged (no vehicle)

Controls:

not required

Amount / concentration applied:

TEST MATERIAL
- Amount(s) applied (volume or weight with unit): 0.5 mL

Duration of treatment / exposure:

24 h

Observation period:

72 h

Number of animals:

12 rabbits (6 with intact skin and 6 with abraded skin)

Details on study design:

- Area of exposure: Back of the animals
- % coverage: Test substance (0.5 mL) was applied under a surgical patch (1 inch x 1 inch) to the intact or abraded skin site on each animal.
- Type of wrap used: The patches were fixed to the application site by means of adhesive tape and the entire trunk of the rabbits was wrapped with an impervious material to maintain the test patches in position and to retard evaporation of volatile substances.

REMOVAL OF TEST SUBSTANCE
- After an exposure period of 24 h, the patches and the applied material were removed.

SCORING SYSTEM:
- Skin reactions were scored at 24 and 72 h after application according to Draize scoring system (1944).

Irritation parameter:

erythema score

Basis:

mean

Remarks:

of 6 animals

Time point:

other: 24 and 72 h

Score:

1.3

Max. score:

4

Reversibility:

no data

Remarks on result:

other: intact skin

Irritation parameter:

edema score

Basis:

mean

Remarks:

of 6 animals

Time point:

other: 24 and 72 h

Score:

0.3

Max. score:

4

Reversibility:

no data

Remarks on result:

other: intact skin

Irritant / corrosive response data:

- After 24 h, very slight or well-defined erythema was generally noted in animals.
- After 72 h, very slight erythema, slight to distinct scaliness and very slight oedema were noted in 4/12 rabbits.
- After 24 and 72 h, focal haemorrhages were noted on the abraded skin of one rabbit. It was stated by the author that this rabbit had an abnormally sensitive skin.
- No distinct differences were noted between the reactions on the intact skin and abraded skin.

Other effects:

None

Table 7.3.1/1: Skin irritation data for individual rabbits

Rabbit number	Irritation scores (Intact skin)
Rabbit number	24 h		72 h		Mean (24 and 72 h)
	Erythema	Oedema	Erythema	Oedema	Erythema	Oedema
1	2	1	1	1	1.5	1.0
2	1	0	2	0	1.5	0.0
3	2	0	1	1	1.5	0.5
4	1	0	1	0	1.0	0.0
5	1	0	1	0	1.0	0.0
6	1	0	1	0	1.0	0.0
Mean (all 6 animals)					1.3	0.3

Interpretation of results:

not irritating

Remarks:

Migrated information Criteria used for interpretation of results: EU

Conclusions:

Under the test conditions, Reaction mass of 3,6-dihydro-4-methyl-2-phenyl-2H-pyran and tetrahydro-4-methylene-2-phenyl-2H-pyran is not classified as irritating to skin according to the Directive 67/548/EEC and the CLP Regulation.

Executive summary:

In a primary dermal irritation study performed similarly to OECD Guideline 404, 12 New Zealand White rabbits were dermally exposed to 0.5 mL of Reaction mass of 3,6-dihydro-4-methyl-2-phenyl-2H-pyran and tetrahydro-4-methylene-2-phenyl-2H-pyran, under an occlusive patch (1 inch X 1 inch) to intact or abraded skin of the dorsal region. After an exposure period of 24 h, the patches and the applied material were removed and skin reactions were scored by Draize method. A second reading was recorded 48 h later (72 h after application). Irritation scores at 48 h after application were derived using the worst case scores recorded at 24 or 72 h.

After 24 h, very slight or well-defined erythema was generally noted in animals. After 72 h, very slight erythema, slight to distinct scaliness and very slight oedema were noted in 4/12 rabbits. After 24 and 72 h, focal haemorrhages were noted on the abraded skin of one rabbit. It was stated by the author that this rabbit had an abnormally sensitive skin. No distinct differences were noted between the reactions on the intact skin and abraded skin.

The calculated mean scores for each individual lesion for all animals within scoring times (24 and 72 h) were as follows: 1.3 for erythema score (intact skin) and 0.3 for oedema score (intact skin).

Under the test conditions, Reaction mass of 3,6-dihydro-4-methyl-2-phenyl-2H-pyran and tetrahydro-4-methylene-2-phenyl-2H-pyran is not classified as irritating to skin according to the Directive 67/548/EEC and the CLP Regulation.

Endpoint conclusion:

no adverse effect observed (not irritating)

Reference

Endpoint:

eye irritation: in vivo

Type of information:

experimental study

Adequacy of study:

key study

Study period:

1981

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: Non GLP study conducted similarly to OECD Guideline 405 with deviations: no data about purity and no certificate of analysis of the test substance; no details on environmental conditions; age of animals at the start of study was not reported

Reason / purpose for cross-reference:

reference to same study

Reason / purpose for cross-reference:

reference to other study

Qualifier:

equivalent or similar to guideline

Guideline:

OECD Guideline 405 (Acute Eye Irritation / Corrosion)

Deviations:

yes

Remarks:

no GLP statement; no data about purity and no certificate of analysis of the test substance; no details on environmental conditions; age of animals at the start of study was not reported

Principles of method if other than guideline:

Not applicable

GLP compliance:

yes

Species:

rabbit

Strain:

New Zealand White

Details on test animals or tissues and environmental conditions:

- Housing: Animals were housed individually in cages.

Vehicle:

unchanged (no vehicle)

Controls:

not required

Amount / concentration applied:

TEST MATERIAL
- Amount(s) applied (volume or weight with unit): 0.1 mL
- Concentration (if solution): Undiluted

Duration of treatment / exposure:

24 h

Observation period (in vivo):

7 days

Number of animals or in vitro replicates:

Six

Details on study design:

REMOVAL OF TEST SUBSTANCE
- Washing: Eyes were not washed following instillation and the animals were released immediately.

SCORING SYSTEM: Ocular lesions were observed at 24, 48 and 72 h and 7 days after instillation and graded according to a scale comparable to OECD guideline 405.

TOOL USED TO ASSESS SCORE: Ocular reactions were read using a binocular magnifying glass. The diagnosis of corneal damage was confirmed, if necessary, by staining the eyes of the animals with fluorescein-impregnated papers. After flushing the excess fluorescein solution, the eyes were examined in a dark room under UV illumination.

Irritation parameter:

cornea opacity score

Basis:

mean

Remarks:

of 6 animals

Time point:

other: average of 24, 48 and 72 h

Score:

0

Max. score:

4

Reversibility:

other: not applicable

Irritation parameter:

iris score

Basis:

mean

Remarks:

of 6 animals

Time point:

other: average of 24, 48 and 72 h

Score:

0

Max. score:

2

Reversibility:

other: not applicable

Irritation parameter:

conjunctivae score

Basis:

mean

Remarks:

of 6 animals

Time point:

other: average of 24, 48 and 72 h

Score:

0.5

Max. score:

3

Reversibility:

fully reversible within: 7 days

Irritation parameter:

chemosis score

Basis:

mean

Remarks:

of 6 animals

Time point:

other: average of 24, 48 and 72 h

Score:

0.11

Max. score:

4

Reversibility:

fully reversible within: 2 days

Irritant / corrosive response data:

- Slight redness and slight swelling of the conjunctivae were noted in 5/6 and 2/6 rabbits, respectively.
- Within 7 days, these lesions had cleared up completely.

Other effects:

None

Table 7.3.2/1: Scores for ocular lesions

Animal no.	Cornea				Iris				Conjunctivae redness				Conjunctivae chemosis
Animal no.	24 h	48 h	72 h	Mean*	24 h	48 h	72 h	Mean*	24 h	48 h	72 h	Mean*	24 h	48 h	72 h	Mean*
1	0	0	0	0	0	0	0	0	1	1	0	0.67	1	0	0	0.33
2	0	0	0	0	0	0	0	0	1	0	0	0.33	0	0	0	0.00
3	0	0	0	0	0	0	0	0	1	1	0	0.67	0	0	0	0.00
4	0	0	0	0	0	0	0	0	1	1	1	1.00	1	0	0	0.33
5	0	0	0	0	0	0	0	0	1	0	0	0.33	0	0	0	0.00
6	0	0	0	0	0	0	0	0	0	0	0	0.00	0	0	0	0.00
Mean^#				0				0				0.50				0.11

*mean of scores at 24, 48 and 72 h

^#mean of scores of all 6 animals

Interpretation of results:

not irritating

Remarks:

Migrated information Criteria used for interpretation of results: EU

Conclusions:

Under the test conditions, Reaction mass of 3,6-dihydro-4-methyl-2-phenyl-2H-pyran and tetrahydro-4-methylene-2-phenyl-2H-pyran is not classified as irritating to eyes according to the Directive 67/548/EEC and the CLP Regulation.

Executive summary:

In an eye irritation study conducted similarly to the OECD Guideline 405, six rabbits of the New Zealand White strain were exposed to 0.1 mL of Reaction mass of 3,6-dihydro-4-methyl-2-phenyl-2H-pyran and tetrahydro-4-methylene-2-phenyl-2H-pyran in their one eye, while the other eye remained untreated and served as control. The eyelids were then gently held together for 1 second to avoid any loss of the test material. Eyes were not washed and ocular reactions were read at 24, 48 and 72 h and 7 days following instillation using a binocular magnifying glass. The diagnosis of corneal damage was confirmed, if necessary, by staining the eyes of the animals with fluorescein-impregnated papers. After flushing the excess fluorescein solution, the eyes were examined in a dark room under UV illumination. Ocular reactions were graded according to a scale comparable to the OECD Guideline 405.

Slight redness and slight swelling of the conjunctivae were noted in 5/6 and 2/6 rabbits, respectively. Within 7 days, these lesions had cleared up completely. The calculated mean scores for each individual lesion for all animals within three scoring times (24, 48 and 72 h) were as follows: 0.00 for cornea score; 0.00 for iris score; 0.50 for conjunctivae score and 0.11 for chemosis score. In this study, 2-phenyl-4-methyldihydropyran is not considered as irritating to eyes in rabbits.

Under the test conditions, Reaction mass of 3,6-dihydro-4-methyl-2-phenyl-2H-pyran and tetrahydro-4-methylene-2-phenyl-2H-pyran is not classified as irritating to eyes according to the Directive 67/548/EEC and the CLP Regulation.

Endpoint conclusion:

no adverse effect observed (not irritating)

Endpoint conclusion:

no study available

In a primary skin irritation study, 12 New Zealand White rabbits were dermally exposed to 0.5 mL of Reaction mass of 3,6-dihydro-4-methyl-2-phenyl-2H-pyran and tetrahydro-4-methylene-2-phenyl-2H-pyran, under an occlusive patch (1 inch X 1 inch) to intact or abraded skin of the dorsal region. After an exposure period of 24 h, the patches and the applied material were removed and skin reactions were scored by Draize method. A second reading was recorded 48 h later (72 h after application). Irritation scores at 48 h after application were derived using the worst case scores recorded at 24 or 72 h.

After 24 h, very slight or well-defined erythema was generally noted in animals. After 72 h, very slight erythema, slight to distinct scaliness and very slight oedema were noted in 4/12 rabbits. After 24 and 72 h, focal haemorrhages were noted on the abraded skin of one rabbit. It was stated by the author that this rabbit had an abnormally sensitive skin. No distinct differences were noted between the reactions on the intact skin and abraded skin. The calculated mean scores for each individual lesion for all animals within scoring times (24 and 72 h) were as follows: 1.3 for erythema score (intact skin) and 0.3 for oedema score (intact skin).

In an eye irritation study conducted similarly to the OECD Guideline 405, six rabbits of the New Zealand White strain were exposed to 0.1 mL of Reaction mass of 3,6-dihydro-4-methyl-2-phenyl-2H-pyran and tetrahydro-4-methylene-2-phenyl-2H-pyran in their one eye, while the other eye remained untreated and served as control. The eyelids were then gently held together for 1 second to avoid any loss of the test material. Eyes were not washed and ocular reactions were read at 24, 48 and 72 h and 7 days following instillation using a binocular magnifying glass. The diagnosis of corneal damage was confirmed, if necessary, by staining the eyes of the animals with fluorescein-impregnated papers. After flushing the excess fluorescein solution, the eyes were examined in a dark room under UV illumination. Ocular reactions were graded according to a scale comparable to the OECD Guideline 405.

Slight redness and slight swelling of the conjunctivae were noted in 5/6 and 2/6 rabbits, respectively. Within 7 days, these lesions had cleared up completely. The calculated mean scores for each individual lesion for all animals within three scoring times (24, 48 and 72 h) were as follows: 0.00 for cornea score; 0.00 for iris score; 0.50 for conjunctivae score and 0.11 for chemosis score. In this study, Reaction mass of 3,6-dihydro-4-methyl-2-phenyl-2H-pyran and tetrahydro-4-methylene-2-phenyl-2H-pyran is not considered as irritating to eyes in rabbits.

No respiratory irritation study available. However, such effects are unlikely as Rosyrane is not irritating to the skin or eyes of rabbits and its low volatility indicates that significant inhalation is unlikely under anticipated conditions of use.

Justification for selection of skin irritation / corrosion endpoint:
Reliable in vivo study

Justification for selection of eye irritation endpoint:
Reliable in vivo study

Based on the results of a reliable in vivo skin irritation and eye irritation study, and supported by data from acute dermal toxicity and skin sensitisation studies, classification under the EU DSD or CLP regulations as a skin or eye irritant is not required.

Similarly, Rosyrane does not meet the criteria for classification as a respiratory tract irritant.