3,3'-[methylenebis(oxymethylene)]bisheptane

Endpoint summary

Description of key information

2-ethylhexylal was identified as not irritating to skin and eyes in in vivo test performed according to OECD TG 404 and 405 (GLP). An in vitro test shows that 2-ethylhexylal is not corrosive OECD TG 431 and GLP).

Key value for chemical safety assessment

Skin irritation / corrosion

Link to relevant study records

Reference

Endpoint:

skin irritation: in vitro / ex vivo

Type of information:

experimental study

Adequacy of study:

key study

Study period:

From 2008-04-29 to 2008-05-02

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: GLP lab following OECD guideline

Qualifier:

according to guideline

Guideline:

other: OECD Guideline 431 (In vitro skin corrosion: Human Skin Model Test)

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Species:

human

Strain:

other: Episkin Standard Model

Type of coverage:

open

Vehicle:

unchanged (no vehicle)

Controls:

not required

Duration of treatment / exposure:

3, 60 and 240 minutes

Observation period:

3 hours after end of exposure

Irritation / corrosion parameter:

other: other: Cell Viability

Value:

> 35

Remarks on result:

other:

Remarks:

Basis: mean. Time point: 240 minutes. Reversibility: no data. Remarks: Following OECD Guideline 431: the cell viability is never below 35% even after 4 hours exposure. (migrated information)

Interpretation of results:

study cannot be used for classification

Remarks:

Migrated information: non corrosive

Conclusions:

According to the obtained results (cell viability never below 35% for tested exposure time) and reporting to the UN and EU classification criterias for corrosive chemical categorisation, we can conclude that the organic solvent 2-ethylhexylal can be classified as non corrosive.

Executive summary:

The objective of this study is to predict and classify the skin corrositivity potential of the chemical product 2-ethylhexylal according to chemical safety regulation, by assessment of its effect on a reconstructed human epidermis.

The principle of this test is based on the experience that corrosive chemicals show cytotoxic effect following short-term exposure on the stratum corneum of the epidermis. The test protocol does not provide adequate information on skin irritation. The assay was conducted according to the OECD guideline n° 431 "In vitro skin corrosion: Human Skin Model Test".

The Episkin is a highly differentiated and stratified epidermis validated model comprising the main basal, supra basal, spinous and granular layers and a functional stratum corneum obtained after a culture period. Its use for skin corrositivity testing involves topical application of the test material to the surface of the epidermis, and the subsequent assessment of its effects on cell viability.

The selected positive and negative reference chemicals are phosphate buffer saline and acetic acid glacial.

Corrositivity potential of 2-ethylhexylal involved topical application of test item to the surface of the reconstructed human epidermis and the subsequent assessment of its effect on cell viability. 10µl of the test item was applied topically to the epidermal model for 3, 60 and 240 minutes (3 epidermis units were used per test material, 2 for positive and 1 for negative controls and time exposure). At the end of the treatment, all residual test item and chemical controls were removed by thoroughly rinsing epidermis units with 25 ml of sterile phosphate buffered saline solution. The resulting cell viability was further assessed by incubating tissues for 3 hours at 37°C, 5% CO2 atmosphere with MTT (0.3 mg/ml) in assay medium. The basis of this test is that viable cells metabolize MTT into intra-cellular formazan crystals. The precipitated formazan was finally extracted using acidified isopropanol and quantified spectrophotometrically at 550 nm by comparison to a blank (acidified propanol).

According to the obtained results (cell viability never below 35% for tested exposure time) and reporting to the UN and EU classification criteria for corrosive chemical categorization, we can conclude that the organic solvent 2-ethylhexylal can be classified as non corrosive (OECD 431: non-corrosive to skin if the viability after 3 minutes exposure is greater than or equal to 50% and the viability after 1 hour exposure is greater than or equal to 15%).

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

Reliability:

1 (reliable without restriction)

Qualifier:

according to guideline

Guideline:

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

Qualifier:

according to guideline

Guideline:

OECD Guideline 405 (Acute Eye Irritation / Corrosion)

GLP compliance:

yes

Species:

rabbit

Strain:

New Zealand White

Details on test animals or tissues and environmental conditions:

- Source: breeding farm VELAZ s.r.o., Kolec u Kladna, Czech Republic, RCH CZ 21760152
- Age at study initiation: 4-5 months
- Weight at study initiation: 2.3-2.4 kg
- Housing: Conventional animal room – individually in metallic cages
- Diet (e.g. ad libitum): Standard pelleted diet TM-MAK 1 for rabbits and guinea pigs ad libidum (producer: Ing. Mrkvicka Miroslav – Vyroba krmnych smesi, Mlyn Kocanda, 252 42 Jesenice u Prahy)
- Water (e.g. ad libitum): Drinking tap water ad libitum (quality corresponding to the Regulation No.: 252/2004 Czech Coll. Of Law)
- Acclimation period: not specified

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): used in delivered form (undiluted)

Duration of treatment / exposure:

Duration of exposure corresponds to duration of observation

Observation period (in vivo):

The eyes were examined at 1, 24, 48 and 72 hours after application, then once daily. After recording the observations at 24 hours, the eyes of rabbit were examined with the aid of fluorescinein and the ophthamoscopy. The grades of ocular reaction for single animal (observation of conjunctivae, cornea and iris) were recorded at each examination.

Number of animals or in vitro replicates:

3 (1 male and 2 females)

Details on study design:

REMOVAL OF TEST SUBSTANCE
- Washing (if done): No
- Time after start of exposure: Not relevant

SCORING SYSTEM:
CORNEA
0 - No ulceration or opacity
1 - Scattered or diffuse areas of opacity; details of iris clearly visible
2 - Easily discernible translucent area;details of iris slightly obscured
3 – Nacrous area, no details of iris visible, size of pupil barely discernible
4 – Opaque cornea, iris not discernible through the opacy
Maximum possible: 4

IRIS
0 - Normal
1 – Markedly deepened rugae, congestion, swelling, moderate circumcorneal hyperemia ; or injection ; iris reactive to light (a sluggish reaction is considered to be an effect)
2 – Hemorrhage, gross destruction, or no reaction to light
Maximum possible: 2

CONJUNCTIVAE
0 - Redness (refers to palpebral and bulbar conjunctivae; excluding cornea and iris) normal
1 - Some blood vessels hyperarmic (injected)
2 - Diffuse, crimson color, individual vessels not easily discernible
3 - Diffuse beefy red
Maximum possible: 3

CHEMOSIS
0 - Normal no alterations
1 - Some swelling above normal
2 - Obvious swelling with partial eversion of lids
3- Swelling with lids about half closed
4 - Swelling with lids more than half closed
Maximum possible: 4

TOOL USED TO ASSESS SCORE: hand-slit lamp / biomicroscope / fluorescein

Irritation parameter:

chemosis score

Basis:

animal #3

Time point:

24/48/72 h

Score:

0

Max. score:

4

Irritation parameter:

chemosis score

Basis:

animal #2

Time point:

24/48/72 h

Score:

0

Max. score:

4

Irritation parameter:

chemosis score

Basis:

animal #1

Time point:

24/48/72 h

Score:

0

Max. score:

4

Irritation parameter:

conjunctivae score

Basis:

animal #3

Time point:

72 h

Score:

0

Max. score:

3

Irritation parameter:

conjunctivae score

Basis:

animal #2

Time point:

72 h

Score:

0

Max. score:

3

Irritation parameter:

conjunctivae score

Basis:

animal #1

Time point:

72 h

Score:

0

Max. score:

3

Irritation parameter:

conjunctivae score

Basis:

animal #3

Time point:

48 h

Score:

1

Max. score:

3

Reversibility:

fully reversible within: 72 hours

Irritation parameter:

conjunctivae score

Basis:

animal #3

Time point:

24 h

Score:

2

Max. score:

3

Reversibility:

fully reversible within: 72 hours

Irritation parameter:

conjunctivae score

Basis:

animal #2

Time point:

48 h

Score:

1

Max. score:

3

Reversibility:

fully reversible within: 72 hours

Irritation parameter:

conjunctivae score

Basis:

animal #2

Time point:

24 h

Score:

2

Max. score:

3

Reversibility:

fully reversible within: 72 hours

Irritation parameter:

iris score

Basis:

animal #3

Time point:

24/48/72 h

Score:

0

Max. score:

2

Irritation parameter:

iris score

Basis:

animal #2

Time point:

24/48/72 h

Score:

0

Max. score:

2

Irritation parameter:

iris score

Basis:

animal #1

Time point:

24/48/72 h

Score:

0

Max. score:

2

Irritation parameter:

cornea opacity score

Basis:

animal #3

Time point:

24/48/72 h

Score:

0

Max. score:

4

Irritation parameter:

cornea opacity score

Basis:

animal #2

Time point:

24/48/72 h

Score:

0

Max. score:

4

Irritation parameter:

cornea opacity score

Basis:

animal #1

Time point:

24/48/72 h

Score:

0

Max. score:

4

Irritation parameter:

conjunctivae score

Basis:

animal #1

Time point:

other: 1 hour

Score:

2

Max. score:

4

Reversibility:

not fully reversible within: 48 hours

Irritation parameter:

conjunctivae score

Basis:

animal #1

Time point:

24 h

Score:

1

Max. score:

3

Reversibility:

not fully reversible within: 48 hours

Irritation parameter:

chemosis score

Basis:

animal: #1, 2 and 3

Time point:

other: 1 hour

Score:

1

Max. score:

4

Reversibility:

fully reversible within: 24 hours

Irritant / corrosive response data:

Please refer to “Overall irritation/corrosion results”

Body weights were recorded in the table below:

Rabbit No.	Clinical observation	Body weight (in kg)
		prior to application	at termination
1	No changes	2.40	2.60
2	No changes	2.40	2.70
3	No changes	2.30	2.50

Interpretation of results:

not irritating

Remarks:

Migrated information Criteria used for interpretation of results: EU

Conclusions:

Examination of eye irritation after single application demonstrated, that the test substance, 2-ethylhexylal, is not irritating for eye of rabbit.

Executive summary:

The test substance,2-ethylhexylal, was tested for the assessment of eye irritation/corrosion effects using albino rabbit (New Zealand Albino breed).

The test was performed according to the Method B.5 Acute Toxicity: Eye Irritation/Corrosion. Council Regulation (EC) No.440/2008, published in O.J. L 142, 2008.

The test was performed initially using one animal (No. 7). If the results of this test indicate the substance to be corrosive or a severe irritant to the eye, the response was confirmed using two additional animals (No. 8 and No. 9).

The following changes were observed on eye at 1 hour after application: conjunctivae - diffuse, crimson color, individual vessels not easily discernible; chemosis – some swelling above normal in all rabbits. Conjunctivae – diffuse, crimson color, individual vessels not easily discernible or some blood vessels hyperaemic (injected) were observed in all rabbits at the 24 hours after application. Conjunctivae – some blood vessels hyperaemic (injected) were observed in two rabbits (No. 8 and No. 9) at the 48 hours after application. No changes on the conjunctival sac were observed at the 72 hours after application in all animals.

No clinical signs of systemic intoxication were detected.

 

Examination of eye irritation after single application demonstrated, thatthe test substance, 2-ethylhexylal, is not irritating for eye of rabbit.

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed (not irritating)

Respiratory irritation

Endpoint conclusion

Endpoint conclusion:

no study available

Justification for classification or non-classification

2-ethylhexylal is not classified for its irritating effects to skin and eyes according to the CLP principles.