Oils, cinnamon

Endpoint summary

Description of key information

Skin: corrosive to skin (OECD TG 431 and OECD TG 439 )
Eye: serious eye damage (OECD TG 438; no prediction can be made, the classification based on skin results)

Key value for chemical safety assessment

Skin irritation / corrosion

Endpoint conclusion

Endpoint conclusion:

adverse effect observed (corrosive)

Eye irritation

Endpoint conclusion

Endpoint conclusion:

adverse effect observed (irreversible damage)

Respiratory irritation

Endpoint conclusion

Endpoint conclusion:

no study available

Additional information

Skin irritation

OECD TG 439:

The skin irritation potential of Cinnamon bark oil was tested in accordance with OECDTG439. Undiluted Cinnamon bark oil was applied to the skin model for 42 minutes. After a 42-hour post-incubation period, determination of the cytotoxic (irritancy) effect was performed using MTT conversion measurements. Cinnamon bark oil was identified as a direct MTT reducer (2.0% viability of the NSMTT control) but did not cause colour interference. The mean corrected tissue viability obtained after 42 minutes treatment with Cinnamon bark oil compared to the negative control tissues was 0.3%. The positive control had a mean cell viability of 1.3% and the OD values of the negative control tissues were 0.969, 0.843 and 0.833. Furthermore, the standard deviation value of the percentage viability of three tissues treated identically was less than 18%, indicating that the test system functioned properly. Based on this result, the substance does need to be classified for skin irritation or skin corrosion.

OECD TG 431

The skin corrosion potential of Cinnamon bark oil was tested according to OECDTG431. A human three-dimensional epidermal model (EpiCS®) was exposed topically to 50 μL undiluted Cinnamon bark oil, distilled water (negative control), or Potassium hydroxide (positive control) for 3 minutes or 1 hour. Cinnamon bark oil was identified as a direct MTT reducer (1.8% viability of the NSMTT control) but did not cause colour interference. Skin corrosion is expressed as the remaining cell viability after exposure to the test item. Both the negative and the positive control were considered valid. The relative mean tissue viability obtained after the 3-minute and 1-hour treatments with Cinnamon bark oil compared to the negative control tissues was 69.9% and 3.7% respectively. Based on these results, Cinnamon bark oil needs to be classified for skin corrosion.

Eye irritation

To evaluate the eye hazard potential of Cinnamon bark oil an isolated chicken eye test was performed according to OECDTG438. 30 μL of the test item was applied to the cornea of each of 3 chicken enucleated eyes and after 10 seconds the corneas were rinsed with physiological saline. After the exposure, toxic effects were measured by qualitative assessment of opacity (0.7, ICE class II), fluorescein retention (1.3, ICE class II), and corneal swelling (7% ICE class II). Valid positive (3x ICE class IV) and negative (3x ICE class I) controls were included. According to the overall in vitro irritancy criteria, the ICE classes combined for the test item led to the result ‘no prediction can be made'. Therefore, the substance is not predicted as causing serious eye damage (Category 1) or as not classified for eye irritation/serious eye damage (No category).

Justification for classification or non-classification

Based on the in vitro test results the substance is corrosive to skin but no prediction could be made on irritating/corrosive to the eyes. However, according to Annex I of the CLP Regulation (1272/2008/EC) skin corrosive substances shall be considered as leading to serious damage to the eyes as wel. Therefore the substance needs to be classified for skin corrosion (Skin Cor. Cat.1/H314 ) and for serious eye damage (Eye Dam. Cat.1/H318).