Propiophenone

Endpoint summary

Description of key information

Non skin irritating

Eye itrritant (Eye Irrit. , H319)

Key value for chemical safety assessment

Skin irritation / corrosion

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed (not irritating)

Eye irritation

Endpoint conclusion

Endpoint conclusion:

adverse effect observed (irritating)

Respiratory irritation

Endpoint conclusion

Endpoint conclusion:

no study available

Additional information

SKIN IRRITATION

Data from secondary sources are available on propiophenone skin irritation potential; details about testing method and procedures are lacking. The substance was applied on the skin of rabbits and after 24 hours the skin resulted mildly irrititated (Marhold, 1986).

Data on human skin irritation potential of the structural analogue acetophenone are reported in literature monograph. The substance tested at a concentration of 2 % in petrolatum produced no irritation in a 48-hr closed-patch test in 25 human subjects (Opdyke, 1978; IUCLID section 7.10.5).

Available information on other structural analogues have also been taken into account. They are all substances sharing with propiophenone the same aromatic scaffold structure, mainly bearing ketons, alcohols or both functional groups. Alcoholic function is expected to not significantly impact the skin irritation potential because it represents a grade of reduction of ketone, possibly involved in redox biological processes.

Only few analogues have been classified as skin irritating (details in the document attached into the endpoint study record), confirming that propiophenone is not expected to be potentially skin irritating.

EYE IRRITATION

The eye irritation potential of the propiophenone was assessed by in-vitro system, according to the Guideline OECD 492. For this purpose, a (RhCE) Reconstructed Human EpiOcular™ Model was used. Prior to the test, the reconstructed tissue was evaluated for its viability and barrier function. The direct reduction ability of MTT and the light interference of the test chemical to MTT absorption was also evaluated prior to the test. The test chemical, positive and negative control substances were tested in duplicate. After a pre-treatment of the tissue, it was exposed to the chemical for 30 ± 2 min at standard conditions, after which it was rinsed with Ca2 +/Mg2 +-free DPBS at room temperature. This rinsing step was followed by a 12 ± 2 minutes post - exposure immersion in fresh medium at room temperature and a 120 ± 15 minutes post-exposure incubation in fresh medium at standard culture conditions, prior to performing the MTT assay (180 ± 10 minutes at standard conditions). The mean viability of the test substance is 21.58 %, thus the substance resulted to potentially induce eye irritation or serious eye damage (Licitra, 2016).

Based on the results obtained in the in-vitro test, a discrimination between category 1 and 2 of the CLP Regulation (EC 1272/2008) cannot be reached. The viability mean does not give any indication about the severity of the potential irritating effect, thus data from literature and data on similar substances have been taken into account, in order to clarify the irritation potential.

Data from secondary literature sources are available. Propiophenone, applied on the eye of rabbits, resulted mildly irritating (RTECS database). A second publication describes an experiment in which the compound was tested externally on the eyes of rabbits, and, according to the degree of injury observed after 24 hours, rated on a scale of 1 to 10. The most severely injurious substances have been rated 10. The test item is rated 1 on rabbit eyes (HSDB).

The structural analogous acetophenone is included in Annex VI of the CLP Regulation and is classified as Eye Irrit.2, H319.

Also in this case, the vailable information on other structural analogues have also been taken into account. They are all substances sharing with propiophenone the same aromatic scaffold structure, mainly bearing ketons, alcohols or both functional groups. Alcoholic function is expected to not significantly impact the eye irritation potential because it represents a grade of reduction of ketone, possibly involved in redox biological processes.

In most cases the analogues are not classified as eye irritanting substances; some of them are classified for eye irritating potential (H319), but none is classified for seriuos eye damage (H318) (details in the document attached into the endpoint study record).

Furthermore, the susbtance is used as intermediate, under strictly controlled conditions, thus the possibily of eye contact is very limited: the production processes and the risk management measures implemented in the manufacture plants, can be considered as adequate in order to reduce the risk of exposure to the substance.

In conclusion, a classification as eye irritating substance is proposed for propiophenone, i.e. Eye Irrit. 2 H319, according to the CLP Regulation (EC 1272/2008)

REFERENCE

Hazardous Substances Data Bank (HSDB). Grant W.M. (1986). Toxicology of the Eye. 3rd ed. Springfield, IL: Charles C. Thomas Publisher, p. 1054 * PEER REVIEWED

RTECS® (Registry of Toxic Effects of Chemical Substances).

Justification for classification or non-classification

According to the CLP Regulation (EC 1272/2008), 3.2 Skin corrosion/irritation section, skin Irritation means the production of reversible damage to the skin following the application of a test substance for up to 4 hours.

Based on the available information, propiophenone does not possess any potential for skin irritation.

According to the CLP Regulation (EC 1272/2008), serious eye damage means the production of tissue damage in the eye, or serious physical decay of vision, following application of a test substance, which is not fully reversible within 21 days of application. Eye irritation means the production of changes in the eye, which are fully reversible within 21 days of application. In vitro alternatives that have been validated and accepted can be used to make classification decisions.

Based on the available information, propiophenone can be considered as eye irritant, i.e. classified as Eye Irrit. 2 (H319).

In conclusion, the substance does not meet the criteria to be classified for the skin irritation; a classification as Eye Irrit. 2 (H319) is proposed, according to the CLP Regulation (EC 1272/2008).