Benzenepropanal, 2-methyl-4-(2-methylpropyl)-

Eye irritation

Administrative data

Endpoint:

eye irritation: in vivo

Type of information:

experimental study

Adequacy of study:

key study

Study period:

Sep to Nov 2016

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2016

Report date:

2016

Materials and methods

Test guideline

Test guideline 1

Qualifier:

according to guideline

Guideline:

OECD Guideline 405 (Acute Eye Irritation / Corrosion)

Version / remarks:

2012

Deviations:

no

Test guideline 2

Qualifier:

according to guideline

Guideline:

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

Version / remarks:

2008

Deviations:

no

Test guideline 3

Qualifier:

according to guideline

Guideline:

EPA OPPTS 870.2400 (Acute Eye Irritation)

Version / remarks:

1998

Deviations:

no

GLP compliance:

yes

Test material

Test material information

Constituent 1

Reference substance name:

3-[2-methyl-4-(2-methylpropyl)phenyl]propanal

EC Number:

811-285-3

Cas Number:

1637294-12-2

Molecular formula:

C14H20O

IUPAC Name:

3-[2-methyl-4-(2-methylpropyl)phenyl]propanal

Test material form:

liquid

Specific details on test material used for the study:

Identification: NYMPHEAL
Appearance: Colourless to pale yellow liquid
Batch: SC00018060
Purity/Composition: See Certificate of Analysis
Test item storage: At room temperature protected from light
Stable under storage conditions until: 28 April 2017 (expiry date)

Test animals / tissue source

Species:

rabbit

Strain:

New Zealand White

Remarks:

Albino rabbit, New Zealand White, (SPF-Quality)

Details on test animals or tissues and environmental conditions:

Number of animals 3 Males
Age and body weight At start of dosing, the animals were between 12 and 24 weeks old and body weights were at least 1.5 kg.
Identification Earmark.
Health inspection At least prior to dosing. It was ensured that the animals were healthy and that the eyes were free from any abnormality.
Conditions
Environmental controls for the animal room were set to maintain 18 to 24°C, a relative humidity of 40 to 70%, at least 10 air changes/hour, and a 12-hour light/12-hour dark cycle. Any variations to these conditions were maintained in the raw data and had no effect on the outcome of the study.
Accommodation
Animals were individually housed in labeled cages with perforated floors (Ebeco, Germany, dimensions 67 x 62 x 55 cm) and shelters (Ebeco, Germany, dimensions 40 x 32 x 23 cm). Acclimatization period was at least 5 days before start of treatment under laboratory conditions.
Diet
Pelleted diet for rabbits (Global Diet 2030 from Harlan Teklad®, Mucedola, Milanese, Italy) approximately 100 grams per day. Hay (TecniLab-BMI BV, Someren, The Netherlands) and wooden sticks (Swedish aspen wood, Bioservices, Uden, The Netherlands) were available during the study period.
Water
Free access to tap water.
Diet, water, bedding and cage enrichment evaluation for contaminants and/or nutrients was performed according to facility standard procedures. There were no findings that could interfere with the study.

Test system

Vehicle:

unchanged (no vehicle)

Controls:

yes

Amount / concentration applied:

0.1 mL of Nympheal (100%)

Duration of treatment / exposure:

Single samples of 0.1 mL of NYMPHEAL were instilled into one eye of each of three rabbits. Observations were made 1, 24, 48 and 72 hours and 7 days after instillation.

Observation period (in vivo):

7 days

Number of animals or in vitro replicates:

3 male rabbits

Details on study design:

The study was performed in a stepwise manner and was started by treatment of a single rabbit (sentinel). The two other animals were treated in a similar manner 1 week later, after considering the degree of eye irritation observed in the first animal.
One hour prior to instillation of the test item, buprenorphine (Buprenodale®, Dechra Ltd., Stoke-on-Trent, United Kingdom) 0.01 mg/kg was administered by subcutaneous injection in order to provide a therapeutic level of systemic analgesia.
Five minutes prior to instillation of the test item, two drops of the topical anesthetic alcaine 0.5% (SA Alcon-Couvreur NV, Puurs, Belgium) were applied to both eyes.
Each animal was treated by instillation of 0.1 mL of the test item, in the conjunctival sac of one of the eyes after gently pulling the lower lid away from the eyeball. The lids were then gently held together for about one second to prevent loss of the test item. The other eye remained untreated and served as the reference control.
Immediately after the 24-hour observation, a solution of 2% fluorescein (Merck, Darmstadt, Germany) in water (adjusted to pH 7.0) was instilled into both eyes of each animal to quantitatively determine corneal epithelial damage. This procedure was repeated to assess recovery. Any bright green stained area, indicating epithelial damage, was estimated as a percentage of the total corneal area.
Immediately after fluorescein examination on Day 2, in order to provide a continued level of systemic analgesia, buprenorphine 0.01 mg/kg and meloxicam (Metacam®, Boehringer Vetmed GmbH, Ingelheim/Rhein, Germany) 0.5 mg/kg were administered by subcutaneous injection.
After the final observation, the animals were sacrificed by intra-venous injection of Euthasol® 20% (AST Farma BV, Oudewater, The Netherlands).

Results and discussion

In vivo

Results

Results 1

Irritation parameter:

cornea opacity score

Basis:

animal: 195

Time point:

24/48/72 h

Score:

0

Results 2

Irritation parameter:

iris score

Basis:

animal: 195

Time point:

24/48/72 h

Score:

0

Results 3

Irritation parameter:

conjunctivae score

Basis:

animal: 195

Time point:

24/48/72 h

Score:

1.3

Reversibility:

fully reversible within: 7 days

Results 4

Irritation parameter:

chemosis score

Basis:

animal: 195

Time point:

24/48/72 h

Score:

0.7

Reversibility:

fully reversible within: 72hrs

Results 5

Irritation parameter:

cornea opacity score

Basis:

animal: 211

Time point:

24/48/72 h

Score:

0

Results 6

Irritation parameter:

iris score

Basis:

animal: 211

Time point:

24/48/72 h

Score:

0.3

Reversibility:

fully reversible within: 48hrs

Results 7

Irritation parameter:

conjunctivae score

Basis:

animal: 211

Time point:

24/48/72 h

Score:

2

Reversibility:

fully reversible within: 7 days

Results 8

Irritation parameter:

chemosis score

Basis:

animal: 211

Time point:

24/48/72 h

Score:

2.3

Reversibility:

fully reversible within: 7 days

Results 9

Irritation parameter:

cornea opacity score

Basis:

animal: 212

Time point:

24/48/72 h

Score:

0

Results 10

Irritation parameter:

iris score

Basis:

animal: 212

Time point:

24/48/72 h

Score:

0

Results 11

Irritation parameter:

conjunctivae score

Basis:

animal: 212

Time point:

24/48/72 h

Score:

2

Reversibility:

fully reversible within: 7 days

Results 12

Irritation parameter:

chemosis score

Basis:

animal: 212

Time point:

24/48/72 h

Score:

1.3

Reversibility:

fully reversible within: 7 days

Irritant / corrosive response data:

Irritation
Instillation of 0.1 mL of NYMPHEAL into one eye of each of three rabbits resulted in effects on the cornea, iris and conjunctivae. The effects on the cornea consisted of slight dulling of the normal luster of the cornea and epithelial damage with an area of 25% in one animal only. The corneal injury resolved within 72 hours. Iridial irritation was observed 24 hours after installation for one animal only. The irritation of the conjunctivae consisted of redness, chemosis and discharge and completely resolved within 7 days in all animals.
Corrosion
There was no evidence of ocular corrosion.

Other effects:

Coloration / Remnants
No staining of (peri) ocular tissues by the test item was observed and no test item remnants were seen.
Toxicity / Mortality
No signs of systemic toxicity were observed in the animals during the test period and no mortality occurred.

Any other information on results incl. tables

List of Study Plan Deviations

1. Deviations from the maximum level of daily mean relative humidity occurred.

Evaluation: Laboratory historical data do not indicate an effect of the deviations.

The study integrity was not adversely affected by the deviation.

List of Standard Operating Procedures Deviations

Any deviations from standard operating procedures were evaluated and filed in the study file. There were no deviations from standard operating procedures that affected the integrity of the study.

Applicant's summary and conclusion

Interpretation of results:

Category 2 (irritating to eyes) based on GHS criteria

Conclusions:

Based on these results NYMPHEAL should be classified as Irritating to eyes (Category 2) according to the Regulation (EC) No 1272/2008 on classification, labelling and packaging of items and mixtures (including all amendments).

Executive summary:

SUMMARY

Acute eye irritation/corrosion study with NYMPHEAL in the rabbit.The study was carried out based on the guidelines described in: OECD No.405 (2012) "Acute Eye Irritation / Corrosion" EC, No 440/2008, B5: "Acute Toxicity: Eye Irritation/Corrosion" EPA, OPPTS 870.2400 (1998): "Acute Eye Irritation" JMAFF Guidelines (2000), including the most recent revisions. Single samples of 0.1 mL of NYMPHEAL were instilled into one eye of each of three rabbits. Observations were made 1, 24, 48 and 72 hours and 7 days after instillation. Instillation of NYMPHEAL into one eye of each of three rabbits resulted in effects on the cornea, iris and conjunctivae. The effects on the cornea consisted of slight dulling of the normal luster of the cornea and epithelial damage with an area of 25% in one animal only. The corneal injury resolved within 72 hours. Iridial irritation was observed 24 hours after installation for one animal only. The irritation of the conjunctivae consisted of redness, chemosis and discharge and completely resolved within 7 days in all animals.

Based on these results NYMPHEAL should be classified as Irritating to eyes (Category 2) according to the Regulation (EC) No 1272/2008 on classification, labelling and packaging of items and mixtures (including all amendments).