6,6-dimethylbicyclo[3.1.1]hept-2-ene-2-propionaldehyde

Endpoint summary

Description of key information

Skin corrosion: the substance did not cause skin corrosion based on OECD TG 431

Skin irritation: the substance causes skin irritation based on OECD TG 439

Eye irritation: the substance is an eye irritant based on OECD TG 438

Key value for chemical safety assessment

Skin irritation / corrosion

Endpoint conclusion

Endpoint conclusion:

adverse effect observed (irritating)

Eye irritation

Endpoint conclusion

Endpoint conclusion:

adverse effect observed (irritating)

Respiratory irritation

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed (not irritating)

Additional information

Skin corrosion:

In accordance to OECD guideline 431 and GLP the test substance was examined for its in vitro skin corrosion potential using a human three dimensional epidermal model (EpiDerm (EPI-200)). The test item was applied undiluted (50 μL) directly on top of the skin tissue for 3 and 60 minutes, respectively. The test was performed in duplicate. Negative and positive controls were run in parallel. All acceptance criteria were met and therefore the study was considered valid. Because a color change was observed by adding MTT-medium it was concluded that the test item did interact with the MTT endpoint. In addition to the normal 3-minute and 1-hour procedure, two freeze-killed tissues treated with test item and two freeze-killed negative control treated tissues were used for the cytotoxicity evaluation with MTT at each time point. The non-specific reduction of MTT by the test item was 2.6% and 16.8% of the negative control tissues after 3 minutes and 1 hour respectively. The relative mean tissue viability obtained after 3-minute and 1-hour treatments with the test item compared to the negative control tissues was 90% and 98%, respectively. Because the mean relative tissue viability for the test item was not below 50% after the 3-minute treatment and not below 15% after the 1-hour treatment the test item is considered to be not corrosive. In conclusion, the test item is not corrosive in the in vitro skin corrosion test under the experimental conditions described in this report.

Skin irritation:

In accordance to OECD guideline 439 and GLP the test substance was examined for its in vitro skin irritation potential using EpiDerm™ reconstructed skin membranes. In the in vitro skin irritation test, the skin membranes were topically exposed to the undiluted test substance for 60 min. The test was performed in triplicate. Viability of the epidermal cells was assessed using the MTT test after 42 h of culture. Negative and positive controls were run in parallel. All acceptance criteria were met and therefore the study was considered valid. After exposure to the test substance the mean tissue viability was 9 ± 3 % compared to the concurrent negative control group. Based on the results obtained in the present study the test substance is considered to be a skin irritant.

Eye irritation:

In accordance to OECD guideline 438 and GLP the test substance was examined for its in vitro eye irritating potential using the Isolated Chicken Eye (ICE) Test. In the ICE test, 3 eyes were exposed to 30 µL test substance for 10 seconds. In addition, one negative control eye (30 µL saline) and three positive control eyes (30 µL Benzalkonium Chloride 5% (BAC)) were tested. After the exposure the eyes were rinsed with 20 mL saline and were examined at approximately 0, 30, 75, 120, 180, and 240 minutes after treatment. The test substance caused slight corneal swelling (9%), very slight or slight opacity (mean score of 1.2) and no, very slight or slight to moderate fluorescein retention (mean score of 0.7). Microscopic examination of the corneas revealed very slight erosion and slight necrosis of the epithelium in two corneas. The negative control eye did not show any corneal effect and demonstrated that the general conditions during the tests were adequate. The positive control caused severe corneal effects and demonstrated the ICE test valid to detect severe eye irritants. Microscopic examination of the cornea treated with the negative control (saline) did not reveal any abnormalities, apart from very slight vacuolation (top region) of the epithelium. The positive control caused moderate or severe erosion, slight vacuolation (one cornea; low region) of the epithelium, and endothelial necrosis. Based on these results the test substance is considered to be an eye irritant.

Respiratory irritation

There are no occupational or consumer data indicating respiratory tract irritation. There are also no relevant experimental guidelines or results available that indicate respiratory irritation, therefore respiratory irritation is not anticipated. The ECHA guidance presents (R7a: 7.2.12.1, 2017) that respiratory irritation may be indicated when the substance is a severe irritant. The substance is a skin and eye irritant, but not corrosive and therefore it is not likely to be a respiratory irritant.

Justification for classification or non-classification

The substance has to be classified as Skin Irrit. 2 and shall be labelled with H315: Causes skin irritation according to EU CLP (EC No. 1272/2008 and its amendments).

The substance has to be classified as Eye Irrit. 2 and shall be labelled with H319: Causes serious eye irritation according to EU CLP (EC No. 1272/2008 and its amendments).

The substance is not considered a respiratory irritant in absence of human data and such effect is not indicated based on absence of skin corrosion and eye severe eye damage.