Ethyl acrylate

Endpoint summary

Description of key information

Ethyl acrylate is irritating to eyes, respiratory system and skin.

Additional information

Skin irritation:

The potential of ethyl acrylate to cause dermal corrosion was assessed in the EpiDerm skin corrosivity test according to OECD guideline 431 conducted by BASF AG. Under the conditions of the test, ethyl acrylate showed a corrosive potential (BAMM, 2005). The EpiDerm study has not been validated for this class of chemicals. In order to allow a clear differentiation of corrosive potential of the substance, a dermal irritation / corrosion test in White New Zealand rabbits was performed by BASF AG according to OECD guideline 404. The undiluted test substance was applied for 1 and 4 hours to the intact rabbit skin under semiocclusive dressing, respectively. After removal of the patch, the application area was washed off. The exposure to the substance for 1 hour caused slight or moderate erythema during the observation period until day 7. The average score for irritation was 2.0 for erythema and 0.0 for edema. After the exposure period of 4 hours, slight to marked erythema were observed during the observation period until day 7. Average scores were 2.2 for erythema and 0.0 for edema. The cutaneous reactions were reversible in all animals in both experiments within 14 days (BAMM, 2005).

In addition, there are several older studies. Ethyl acrylate was applied under occlusive patch for four hours on the skin of rabbits (Rohm & Haas, 1991). Severe erythema and severe edema were observed at 1, 24, 48 and 72 hours. Severe erythema was observed on Days 7 and 14. Slight edema was observed on Day 7 and no edema was observed on Day 14. All animals showed eschar or concave eschar with peripheral healing by fibrosis. In another study, ethyl acrylate (purity ca. 99 %) was tested by applying undiluted ethyl acrylate occlusively for 1, 5 or 15 minutes as well as for 20 hours to the rabbit skin. Irritation was determined 24 hours and 8 days after application. Twenty four hours following the 1-minute application, moderate erythema and edema were seen. The 5- and 15-minute applications caused strong erythema and edema seen 24 hours following application. The 20-hour exposure caused additional slight necrosis in addition to erythema and edema. Eight days after the applications, only slight scaling was observed for the 1-minute application, while the 5- and 15-minute applications showed slight erythema and scaling. The 20-hour application caused slight necrosis of the upper skin layer and scaling (BASF AG, 1978). In a third study, ethyl acrylate was applied to intact and abraded skin of rabbits and occluded for 24 hours. Evidence of irritation at 24 hours included well defined to severe erythema, moderate to severe edema and a general increase in turgor in both intact and abraded skin. Evidence of irritation persisted to 72 hours in all cases. A Primary Irritation (PI) Score of 6.25 was determined based on the Draize scoring procedure (Norsolor, 1980).

Eye irritation:

Since there is no OECD-Guideline 405 study on eye irritation potential of Ethyl acrylate, a weight of evidence approach was followed for the assessment. Three older studies which were reliable with restrictions were considered.

The instillation of one drop of undiluted ethyl acrylate in the eye of two rabbits caused strong redness of the conjunctiva in both animals. In one rabbit, opacity of the cornea was observed within the first 24 hours. After 24 hours, a slight redness of the conjunctiva was observed only in one animal. The effects were completely reversible after five days (BASF AG, 1958). In a second study, one eye of six rabbits was instilled with 0.1 ml of ethyl acrylate. The eyes were examined 24, 48 and 72 hours after dosing. Mild to severe conjunctival inflammation and some corneal opacity and iritis were seen at 24 hours. One animal was terminated due to the severity of the lesions. The eyes of the other five animals either cleared or had reduced irritation by 72 hours. It was concluded by the authors that ethyl acrylate was an ocular irritant (Norsolor, 1980). In a third study, gradually decreasing amounts of undiluted EA were applied directly to the corneas of 5 rabbits as described by Carpenter and Smyth (1946). It was found that 0.5 mL produced severe necrosis of the corneas within 24 hrs, and that 0.1 mL produced moderate necrosis within the same period of time (Pozzani 1949).

Taking into account all the presented information, it was concluded that EA is an eye irritant.

Respiratory irritation:

There exists no standard test method for the assessment of respiratory irritation. Thus, the labelling of EA with "R 37, Irritating to respiratory tract" according to current EU regulations is not based on results of a specific respiratory irritation test, but on considerations on the general irritation potential of EA. There is evidence that ethyl acrylate causes respiratory irritation following repeated inhalation exposure. In addition, an Alarie Assay was performed by De Ceaurriz et al. (1981). The exposure to approximately 1.3 mg EA/L for approximately 5 min caused a 50 % decrease in the respiration rate (RD50 = ca. 1.3 mg/L air). Silver et al. (1981) confirmed the respiratory irritancy of ethyl acrylate by measuring its effect on the respiratory frequency, tidal volume, minute ventilation, and rectal temperature as indices for irritancy.

Thus, labelling with R 37 is confirmed on the basis of all of the respective data mentioned in this IUCLID5 -Registration Dossier.

Justification for classification or non-classification

EU classification according to Annex I of Directive 67/548/EEC: Xi, R36/37/38

GHS classification (GHS UN rev.3, 2009):

- Skin corrosion/irritation: Category 2

- Serious eye damage/eye irritation: Category 2A (Category 2 under CLP)

- Specific target organ toxicity, Single exposure: Category 3 (May cause respiratory irritation)