Cinnamomum cassia, ext.

Endpoint summary

Description of key information

Skin irritation/corrosion (OECDTG439): positive voor skin irritation/corrosion

Skin corrosion (OECDTG431 and study equivalent to OECDTG402): corrosive

Eye irritation (OECDTG438): not irritating, however based on skin results serious eye damage has to be concluded (see justification)

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 Cassia oil was tested in accordance with OECDTG439. Undiluted Cassia 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. Cassia oil was identified as a direct MTT reducer (1.8% viablility of the NSMTT control) but did not cause colour interference. The mean corrected tissue viability obtained after 42 minutes treatment with Cassia oil compared to the negative control tissues was 0.2%. 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. 

OECD TG 431
The skin corrosion potential of Cassia oil was tested according to OECDTG431. A human three dimensional epidermal model (EpiCS®) was exposed topically to 50 μL undiluted Cassua oil, distilled water (negative control), or Potassium hydroxide (positive control) for 3 minutes or 1 hour. Cassia oil was identified as a direct MTT reducer (1.6% 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 81.6% and 9.4% respectively. 

Study equivalent to OECD 402 (acute dermal toxicity)
This acute dermal toxicity study was performed according to an equivalent of guideline OECD 402 (acute dermal toxicity) but with a deviating dose (1000 mg/kg bw instead of 2000 mg/kg bw). 5 male and 5 female New Zealand White rabbits were selected. A single dose of the test article (Oil Cassia Chinese redistilled, 1000 mg/kg bw) was applied for 24 hours. Animals were observed for 14 days, for mortality, systemic observations and body weights. All animals were examined for gross pathology. Dermal irritation was scored according to Draize on 24 hours postdose and on days 7 and 14. Eight of ten animals survived. Two males died on day 2 of the observation period. All survivors lost weight during the observation period. Abnormalities in kidneys, spleen, treated skin and yellow nasal discharge were observed in the two males that died on day 2. For the survivors physical signs were noted: diarrhea, few feces, lethargy, soiling of anogenital area and decreased mobility due to severity of the dermal reactions. All animals showed moderate to severe erythema and edema in the observation period. The results of this study could not be used to conclude on a classification of the substance within the criteria as outlined in the CLP Regulation (1272/2008/EC). However the results indicate corrosive properties. 

Eye irritation
OECD TG 439
To evaluate the eye hazard potential of Cassia 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 (0.5, ICE class I), fluorescein retention (1.0, 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 test item led to the result ‘no Category’.

Justification for classification or non-classification

Based on the in vitro and in vivo test results the substance is corrosive to skin but not 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. Therefore the substance needs to be classified for skin corrosion (Skin Corr. 1/H314) and for serious eye damage (Eye Dam. 1/H318).