Registration Dossier

Administrative data

Description of key information

Delta-damascone was evaluated in the in vitro skin irritation test and considered to be irritating to skin. Furthermore, delta-damascone was evaluated in the in vitro Isolated Chicken Eye test and considered to be not irritating to eyes.

Key value for chemical safety assessment

Skin irritation / corrosion

Endpoint conclusion
Endpoint conclusion:
adverse effect observed (irritating)

Eye irritation

Endpoint conclusion
Endpoint conclusion:
no adverse effect observed (not irritating)

Additional information

Skin irritation

Delta-damascone was evaluated in an in vitro skin irritation test using the Reconstructed Human Epidermis (RhE) Test Method (draft OECD guideline) according to GLP (NOTOX, 2010). Delta-damascone was applied undiluted (10 μl) directly on top of the skin tissue. As a negative control, phosphate buffered saline was used and as a positive control, a 5% aqueous solution of sodium dodecyl sulphate. After a 42 hour incubation period, determination of the cytotoxic (irritancy) effect was performed. Cytotoxicity was expressed as the reduction of mitochondrial dehydrogenase activity measured by formazan production from MTT at the end of the treatment. Cell viability was calculated for each tissue as a percentage of the mean of the negative control tissue. Skin irritation potential of the test substance was classified according to remaining cell viability following exposure to the test substance.

The relative mean tissue viability obtained after 15 minutes treatment with delta-damascone compared to the negative control tissues was 5%. Since the mean relative tissue viability for delta-damascone was below or equal to 50% after 15 minutes treatment (cut-off value for skin irritation) it was considered to be an irritant. The positive control had a mean cell viability of 5% after 15 minutes exposure. The absolute mean OD570 (optical density at 570 nm) of the negative control tissues was within the laboratory historical control data range. The standard deviation value of the percentage viability of three tissues treated identically was less than 18%, indicating that the test system functioned properly. It is concluded that this test is valid and that delta-damsacone is a skin irritant in the in vitro skin irritation test.

Eye irritation

Delta-damascone was evaluated neat in the Isolated Chicken Eye (ICE) test, performed according to OECD Guideline 438 and according to GLP (TNO, 2010). Chicken eyes were obtained from slaughter animals used for human consumption. The isolated chicken eyes were exposed to a single application of the test sample for 10 seconds using an application amount of 30 μL. Three main parameters were measured to disclose possible adverse eye effects: corneal thickness (expressed as corneal swelling), corneal opacity and fluorescein retention of damaged epithelial cells. The effects on these parameters were divided into four Irritation categories, viz. I = no effects; II = slight effect; III = moderate effect; IV = severe effect. The combination of the irritation categories for the three parameters (corneal swelling, corneal opacity and fluorescein retention) is defined to correspond to one of the Regulatory GHS Classifications, i. e. not irritating; GHS category 2B – mild irritant/causes eye irritation; GHS category 2A – irritating to eyes; GHS category 1 – irreversible effects on the eye/serious damage to eye.

The negative control eye, treated with physiological saline, showed no corneal effects.

The positive control, treated with a 5% aqueous solution of benzalkonium chloride, caused moderate swelling (corresponding to Irritation category III), severe opacity (Irritation category IV) and severe flourescein retention (Irritation category IV), which corresponds to GHS category 1 – irreversible effects on the eye/serious damage to eye. The calculated overall Irritation Index was 145. (Irritation Index = maximum mean corneal swelling (%) + maximum mean opacity (x 20) + mean fluorescein (x 20). The maximum Irritation Index is 200)

Delta-damascone caused very slight corneal swelling (corresponding to Irritation category I), slight corneal opacity (Irritation category II) and very slight fluorscein retention (Irritation category I), which correspond to an Irritancy class of “Not irritating”. The calculated overall Irritation Index was 32 (out of 200).

In conclusion and based on the results obtained in the ICE test and according to its classification schemes, delta-damascone was considered to be not irritating to eyes.


Effects on skin irritation/corrosion: irritating

Justification for classification or non-classification

Based on the available data and in accordance with Directive 67/548/EEC, delta-damascone has to be classified for skin irritation, Xi – R38: Irritating to skin.

In accordance with EU Classification, Labeling and Packaging of Substances and Mixtures (CLP) Regulation (EC) No. 1272/2008, the substance has to be classified for skin irritation, Cat. 2 – H315: Causes skin irritation.

Based on the available data and in accordance with Directive 67/548/EEC and EU Classification, Labeling and Packaging of Substances and Mixtures (CLP) Regulation (EC) No. 1272/2008, classification is not necessary for eye irritation.