Registration Dossier

Administrative data

Description of key information

1) Skin irritation in guinea-pigs - irritating
2) Skin irritation in rabbits - irritating
3) Skin irritation in humans - not irritating in a 2 % solution in petrolatum
4) Eye irritation in rabbits, according to OECD 405 and EU method B.5 - not irritating

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:

The skin irritation potential of benzylidene acetone was evaluated in guinea pigs (Brulos, 1977). The aim of the study was however the development of a test for determining the sensitising potential of cosmetic products in the albino guinea-pig. It consists of the administration of Freund's complete adjuvant by intradermal injection and subsequent application of the test substance topically using an occlusive patch. The technique is therefore particularly well suited for the testing of finished products. Additionally the skin irritation of the substances was tested in a pre-test. The complete method described here gave good results for the detection of weak sensitisers. Since this test avoids the use of an increase in concentration to maximize the reaction nor does make use of intradermal injections as the route of administration it seems particularly well adapted to the testing of finished products whatever their form. Concerning skin irritation benzylidene acetone showed no skin irritation at the concentrations employed (1 % in ethanol, 1 % in aqueous lotion, 1 % in a water-in-oil emulsion, 1% in a oil-in-water emulsion). However, other oil-in-water emulsions have been shown to cause primary irritation. Therefore the test item has to be considered to be irritation to skin.

The test item is also characterised in a publication, which lists the characteristics of benzylidene acetone, which include it to be a sensitiser in humans (Maximisation test) and a skin irritant in rabbits and not irritating in humans (Opdyke, 1973, Fragrance raw materials monographs - benzylidene acetone).

In there it is stated that Benzylidene acetone applied full strength to intact or abraded rabbit skin was mildly irritating (Levenstein, 1972b). In there it is also stated that Benzylidene acetone tested in a 2 % concentration in petrolatum produced no irritation in a 48 hr closed-patch test in 25 human subjects (Kligman, 1972). In conclusion, it has to be stated that the test item is irritating to skin, when exposure occurs to higher concentrations of benzalacetone. Therefore the substance had to be classified as a skin irritant.

Eye irritation:

The substance benzalacetone was investigated for its potential for eye irritation in rabbits in 1999 (Schreiter, 1999) to the method recommended in the OECD Guideline No. 405, "Acute Eye Irritation/Corrosion", Feb. 1987, and EEC Guideline B.5 "Acute Toxicity (Eye Irritation)", Jan. 1997. For the test 0.1 mL of undiluted substance were introduced into the conjunctival sac of the right eye of four rabbits. The eyes were examined and the changes were graded according to a numerical scale one hour, 24, 48 and 72 hours after dosing. After a period of 24 h the eye was stained with fluorescein and carefully washed with 20 mL of physiological sodium chloride solution. The signs of cornea (opacity and area affected), iris (lesion), conjunctivae - (redness, chemosis), and discharge were evaluated as described by DRAIZE. The examinations of cornea, iris and conjunctiva were facilitated by use of optical instruments (e. g. hand slit-lamp). To define epithelial damage, fluorescein was applied to the corneal surface. Very slight signs of irritation were observed on the treated eyes. The following mean values, based on the results from the 24, 48 and 72 hour readings, were calculated: Cornea opacity: 0.0, Iris lesion: 0.0, Redness of conjunctiva: 0.3, Oedema of conjunctiva: 0.0.

The results show that the test compound is not irritating to the eye, as only slight conjunctivae reactions were seen in the animals 1 and 24 h after application of the test substance, which were fully reversible within the observation time. According to the European regulation (EC) No. 1272/2008, the test material does not meet the criteria for classification and will not require labelling as irritating to the eyes.


Effects on skin irritation/corrosion: irritating

Justification for classification or non-classification

Skin irritation:

According to the European regulation (EC) No. 1272/2008, the test material does meet the criteria for classification and will require labelling as irritating to the skin (Cat. 2, H315).

Eye irritation:

According to the European regulation (EC) No. 1272/2008, the test material does not meet the criteria for classification and will not require labelling as irritating to the eyes.