Reaction mass of octadecyl heptanoate and octadecyl octanoate

Endpoint summary

Description of key information

Skin, rabbit: not irritating
Eye, rabbit: not irritating

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:

no adverse effect observed (not irritating)

Respiratory irritation

Endpoint conclusion

Endpoint conclusion:

no study available

Additional information

Skin irritation

List No. 915-334-0

A skin irritation study was performed with Reaction mass of octadecyl heptanoate and octadecyl octanoate (List No. 915-334-0), according to a protocol similar to OECD 404 (Planchette, 1986). 0.5 g of the test substance was applied to the shaved and abraded skin of 6 male rabbits and held in place by an occlusive dressing for 24 hours. The irritation effects were scored 24 and 72 hours after patch removal. Intact skin: At the 24-h reading time point, 1/6 animals had slight erythema (score 1) at the shaved skin site. The erythema persisted until the 72-hour reading time point. No other skin irritation effects were observed in any animals. Abraded skin: 2/6 animals had slight erythema (score 1) at the 24-hour reading time point, while the severity had increased in one of these animals to moderate erythema (score 2) at the 72-hour reading time point. In the other rabbit, the erythema cleared completely within 72 hours after application. The results of the abraded skin sites were not taken into account for hazard assessment. There was no 48-hour reading time point. To be able to calculate the mean scores, the 48-hour scores were assumed to be the same as those determined 24 hours after patch removal (worst case assumption). The mean erythema scores (over 24, 48 and 72 hours) were 0, 0.67, 0, 0, 0 and 0, for each animal respectively, while all the mean edema scores (over 24, 48 and 72 hours) were 0. Based on the results of the conducted study, the test substance is not considered to be irritating to the skin.

In a non-guideline study, 0.5 mL of the test substance was applied to the shaved and abraded skin of 3 male and 3 female rabbits for 24 hours under occlusive conditions (Cuthbert, 1977). 10% SDS was applied as a control. The skin irritation effects were scored at 0 and 24 hours after patch removal. Intact skin: At the 0-hour reading time point, immediately after patch removal, 6/6 animals had very slight erythema and edema, of which 2/6 rabbits had a score 0.5 and 4/6 a score 1 (for both erythema and edema). At the 48-hour reading time point, the erythema and edema had cleared completely in 5/6 animals. 1/6 animals still had very slight erythema and edema (score 0.5). As there was only one relevant reading time point (48 hours), it was not possible to derive the mean score of the skin irritation effects according to the standard Draize scoring system and hence, the study is considered to be inconclusive.

CAS 66009-41-4

The source substance octadecyl heptanoate (CAS 66009-41-4) is one of the 2 main constituents of the target substance Reaction mass of octadecyl heptanoate and octadecyl octanoate, therefore data on this source substance was included in the dossier.

The potential acute and subacute skin irritating effects of octadecyl heptanoate were reported in two publications by Guillot (1978, 1981). In a non-guideline study, an unknown amount of the undiluted test substance was applied to the skin of 5 rabbits for 1 hour under occlusive conditions. The skin irritation effects were scored according to the primary irritation index at reading time points 1, 24 and 48 hours. The IPP score of 0.13 indicated a slight irritation potential. Based on limited data and the fact that no Draize score was used, the results are considered to be inconclusive and are not taken into account for hazard assessment and classification purposes.

In a second non-guideline study, an unknown amount of the undiluted test substance octadecyl heptanoate was applied to the skin of 3 rabbits for 30 seconds daily, during 8 consecutive weeks. The skin irritation effects were scored daily according to the primary irritation index, and the skin was examined for dryness and thickening. At the end of the exposure period skin samples were examined for histopathological changes. The reversibility of the effects was observed for 8 days after exposure ended. Well defined erythema was seen following application of the undiluted test substance. Moderate hyperacanthosis of the skin and dermal congestion was noted in 3/3 animals. Following repeated application, prolonged or intermittent occurrence of vesicles was noted, occasionally with small papules and erythemous spots or areas. The test substance was considered to be well tolerated by the rabbits. Based on limited data and the fact that no Draize scoring was applied, the results are considered to be inconclusive and are not taken into account for hazard assessment and classification purposes .

Eye irritation

List No. 915-334-0

An eye irritation study was performed with Reaction mass of octadecyl heptanoate and octadecyl octanoate (List No. 915-334-0), according to a protocol similar to OECD 405 (Cuthbert, 1977). 0.1 mL of the test substance was instilled into one eye of 3 male and 3 female rabbits. The animals were observed for 7 days. 4/6 rabbits had slight (score 1) and 2/6 had moderate chemosis (score 2) at the 1-hour reading time point. Slight chemosis persisted in 6/6 animals until the 72-hour reading time point, then cleared completely by 7 days after application. Slight to moderate conjunctivae was observed in 6/6 rabbits at the 1-hour reading time point. The conjunctivae persisted in all animals until the 72-hour reading time point, although the severity was reduced to score 1 in all animals. 7 days after instillation, 2/6 rabbits had slight conjunctivae, while the other 4/6 had no remaining eye effects. No effects were seen on the cornea and iris. The score 0.5 was included as part of the FDA scoring system; for the sake of consistency these scores were rounded up to 1 to calculate the mean scores. The mean cornea score and iris score (over 24, 48 and 72 hours) was 0, respectively. The mean conjunctivae score (over 24, 48 and 72 hours) was 1.33, 0.67, 1, 1, 1.33, and 1 for each single animal, respectively. The mean chemosis score (over 24, 48 and 72 hours) was 1 for all animals. Based on the results of the study, the test substance is not considered irritating to the eyes.

CAS 66009-41-4

The source substance octadecyl heptanoate (CAS 66009-41-4) is one of the 2 main constituents of the target substance Reaction mass of octadecyl heptanoate and octadecyl octanoate, therefore data on this source substance was included.

The potential eye irritating effect of octadecyl heptanoate was reported in two publications by Guillot (1978, 1981). In a non-guideline study, an unknown amount of the test substance was instilled into the eye of 5 rabbits. The reading time points were 1, 24, 48 and 72 h, and 4 and 7 days. The irritation score was 6 (out of 100) at the 1-hour reading time point and was reduced to 0 at the 24-hour reading time point. No severe lesions including corneal opacity were observed. Slight signs of iritis, conjunctival redness, lacrimation and/or chemosis were reported. Since the score was below 10, the test substance was not considered to be irritating to the eye. Based on limited data and the fact that no Draize scoring was applied, the results are not taken into account for hazard assessment and classification purposes .

Overall conclusion for skin and eye irritation

The available data on Reaction mass of octadecyl heptanoate and octadecyl octanoate did not show skin or eye irritation effects. Therefore, Reaction mass of octadecyl heptanoate and octadecyl octanoate is not considered to be a skin irritant or an eye irritant.

Justification for selection of skin irritation / corrosion endpoint:
The selected study is the most adequate and reliable study based on overall quality assessment (refer to the endpoint discussion for further details).

Justification for selection of eye irritation endpoint:
The selected study is the most adequate and reliable study based on overall quality assessment (refer to the endpoint discussion for further details).

Justification for classification or non-classification

The available data on skin and eye irritation do not meet the classification criteria according to Regulation (EC) 1272/2008 or Directive 67/548/EEC, and are therefore conclusive but not sufficient for classification.