1,2,3,5,6,7-hexahydro-1,1,2,3,3-pentamethyl-4H-inden-4-one

Endpoint summary

Description of key information

Skin corrosion: not corrosive based on OECD TG 431 (EpiDerm)

Skin irritation: irritant based on OECD TG 439 (EPISKIN)
Eye irritation: irritant based on OECD TG 438 (ICE)
Respiratory irritation: not a respiratory irritant

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 study available

Additional information

Skin corrosion

The skin corrosive potential of the test substance was tested in vitro using the EpiDerm™ model after a treatment period of 3 and 60 minutes. The study procedures were according to OECD TG 431 and GLP principles. The principle of the assay was based on the measurement of cytotoxicity in reconstructed human epidermal cultures following topical exposure to the test substance by means of the colorimetric MTT reduction assay. The test item showed non-specific MTT-reducing potential. Therefore, additional killed tissue controls were treated with the test item to determine the non-specific reduction of MTT (NSMTT) and the results were corrected to the true MTT metabolic conversion (TODTT). The test item showed no water-colouring potential. The test item showed no corrosive effects. The mean relative tissue viability (% negative control) was ≥ 50% (126.8%, NSMTT-corrected) after 3 min treatment and ≥ 15% (118.3%, NSMTT-corrected) after 60 min treatment. Finally, it is concluded that this test is valid and that the substance is not corrosive under the experimental conditions described.

Skin irritation

The ability of the test substance to induce skin irritation on a human three dimensional epidermal model (EPISKIN Standard model (EPISKIN-TM)) (OECD TG 349, GLP). The possible skin irritation potential of the test substance was tested through topical application of 10 µL for 15 minutes in an in vitro test. After a 42 hours incubation period, determination of the cytotoxic (irritancy) effect was performed. Cytotoxicity is expressed as the reduction of mitochondrial dehydrogenase activity measured by formazan production from (3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyl-tetrazolium bromide) MTT at the end of treatment. Skin irritation is expressed as the remaining cell viability after exposure to the test substance. The relative mean tissue viability obtained after 15 minutes treatment with Cashmeran compared to the negative control tissue was 10.8%. Since the mean relative tissue viability for Cashmeran was below 50% after 15 minutes treatment the test substance is considered to be irritant. The positive control had a mean cell viability of 5.5% after 15 minutes exposure. The standard deviation value of the percentage viability of three tissues treated identically was less than 18%, indicating that the test system functioned properly. Finally, it is concluded that this test is valid and that the substance is irritant in the in vitro skin irritation test under the experimental conditions described.

Eye irritation/corrosion

The eye irritating potential of Cashmeran was determined in an isolated chicken eye test performed according to OECD guideline 438 and under GLP conditions. The test substance caused moderate swelling (20%) of the cornea, moderate or moderate to severe corneal opacity (2.2) and moderate or moderate to severe fluorescein retention (2.3). The negative control eye did not show any corneal effect and demonstrated that the general conditions during the tests were adequate. Furthermore, the positive control eyes showed severe corneal effects and demonstrated the suitability and sensitivity of the ICE to detect severe eye irritants. The irritation index for Cashmeran as defined in the OECD guideline was 110 out of a maximum of 240. Based on the irritation index for Cashmeran the substance does not need to be classified as severely irritating but according to the EU-CLP classification schemes of the ICE, the substance should be classified as irritating.

Respiratory irritation/corrosion

For respiratory irritation mostly human data are used for the assessment because no suitable in vitro or in vivo tests are available that can identify respiratory irritation (REACH guidance R.7.2.3). There are no human data such as indicated in R7.2.3 the ECHA guidance that indicate respiratory reactions of the substance e.g. from consumer experience or occupational exposure. Despite the skin/eye irritation potential, the substance is not corrosive or severely damaging (eye) which minimizes the respiratory irritation hazard (REACH guidance: 7.2.1.2). Also the substance has a low vapour pressure (1 Pa) and viscosity higher than water (31 versus 1 mPa.s), which minimises the exposure via the inhalation route.

Justification for classification or non-classification

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

The substance does not need to be classified according to EU CLP (EC No. 1272/2008 and its amendments) for respiratory tract irritation because it is not a corrosive or severely irritating substance.