2-methoxyethyl 2-cyanoacrylate

Endpoint summary

Description of key information

2 -methoxyethyl 2 -cyanoacrylate is not classified for skin irritation/corrosion as indicated by available information

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)

Additional information

Skin irritation

The analogous material ß-methoxy-iso-propyl cyanoacrylate (MPCA) was examined for its acute dermal irriation properties according to OECD TG 404.

Very slight erythema with or without very slight oedema was oberved at the test site of each animal throughout the first 72 hours after removal of the dressings. Three days later, very slight erythema and oedema were evident in one animal only, resolving by the twelfth day after treatment. Since the test material spread and dried as a fine hard film, the observations were made at the edges. Although the film appeared to be clear, it was difficult to be sure of the condition of the underlying skin. However, it was considered that the reactions, if any, were no worse than those at the margins of the film. The film had begun to crack in one animal 24 hours after bandage removal and in the other animals eight days later. The majority of the film on each test site was still present at termination. The control sites did not show any response to the control procedure.

Eye irritation

The irritation potential of 2 -methoxyethyl 2 -cyanoacrylate to eyes and mucous membranes was evaluated in the HET-CAM (Hen's Egg Test – Chorioallantoic Membrane) by analysing specific effects to the membrane and/or vessels of the CAM of 9 day incubated chicken eggs. The HET-CAM was given preference as polymerization of 2 -methoxyethyl 2 -cyanoacrylate results in a turbid material that might interfere with opacity measurements in BCOP or ICE studies.

2 -Methoxyethyl 2 -cyanoacrylate was tested undiluted. Since the test item started to harden within 30 seconds on the CAM and became turbid, effects were evaluated using the endpoint method (EPM), though exposure period was prolonged to 5 minutes to have the hardening process completed. Coagulation or lysis were not observed after exposure of the test item to the CAM, but slight to moderate haemorrhaging effects were visible. However, in three of six eggs lifting of the cured polymer film resulted in mechanical damage of vessels. Considering all results, the highest summed up score was 8 for haemorrhage. Since the end point method was performed with an extended exposure period with mechanical damage occuring in some of the CAM after removal of the hardend material, and considering that no lytic and coagulating effects were observed, it is reasonable to assume that some of the haemorrhage was due to the mechanical stress linked to the hardening of the material and the subsequent lifting from the CAM. Therefore the summed up score appears to overestimate the irritative potential of 2 -methoxyethyl 2 -cyanoacrylate, hence, 2 -methoxyethyl 2 -cyanoacrylate is assumed to be rather slightly irritating.

Justification for classification or non-classification

Skin irritation

The mean values for erythema and oedema recorded 24, 48 and 72 hours after treatment with the analogous material ß-methoxy-iso-propyl cyanoacrylate did not equal or exceed the EU limit values (DSD/CLP) considered to indicate a significant inflammatory response to treatment.

The structural similarity between MPCA and 2-methoxyethyl 2-cyanoacrylates is significant with MPCA having a methyl group in vicinity of the methoxy group which is not found in 2-methoxyethyl 2-cyanoacrylate. This additional methyl group is considered to be chemically inert and is not expected to contribute to the substance's irritative potential. Hence, 2 -methoxyethyl 2 -cyanoacrylate is not classified for skin irritation/corrosion in analogy to MPCA.

Eye irritation

Since only haemorrhage was observed in the HET-CAM study which seems to be in part caused by mechanical damage when lifting the polymerized material from the CAM, the classification as moderately irritating based on the score found in the study is rather overestimating the irritative potential of 2 -methoxyethyl 2 -cyanoacrylate. Therefore, 2 -methoxyethyl 2 -cyanoacrylate is only considered to be slightly irritating without requirement of classification and labeling according to DSD and CLP, respectively.