Vinyl acetate

Endpoint summary

Description of key information

Recent GLP Compliant Guideline tests (RCC, 2003a; 2003b) indicate only mild irritation of the skin and eyes of rabbits. However severe irritation in the respiratory tract of rats has been reported in repeat-dose studies.

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:

adverse effect observed (irritating)

Additional information

NON-HUMAN INFORMATION

SKIN IRRITATION

The key study is a recent GLP compliant evaluation of the skin irritation potential of vinyl acetate (RCC, 2003a). The study was performed according to current guidelines (OECD 404, B.4 92/69 EEC) and is considered the most suitable study for risk characterisation. Following semi-occlusive application of 0.5 mL of vinyl acetate (99.9% purity) to intact skin, mean erythema scores at 24, 48 and 72 hours after application were 0.7 / 0.3 / 0, giving an overall mean of 0.33. This mild irritation induced by vinyl acetate had disappeared in all animals after 3 days. Oedema was not observed and there were no corrosive effects.

Some earlier studies (including Industrial BIO-Test Labs. Inc., 1972 and Mellon Institute, 1969) may have indicated more pronounced irritation or corrosion of skin after extended exposure periods, however the guideline study of RCC, 2003a is judged to be the most appropriate study available.

EYE IRRITATION

The key study is a recent GLP compliant evaluation of the eye irritation potential of vinyl acetate (RCC, 2003b). The study was performed according to current guidelines (OECD 405, B.5 92/69 EEC) and is considered the most suitable study for risk characterisation.

Undiluted vinyl acetate (0.1 mL, 99.9 % purity) was placed in the conjuctival sacs of three rabbits. One hour after the application mild redness and chemosis of conjunctivae were observed although fully reversible in all animals after 48 and 24 hours, respectively. There was no indication of any change in corneal opacity or iris. The mean scores determined after 24, 48 and 72 hours were 1/0/0 for redness and 0/0/0 for chemosis, corneal opacity and iris. The overall mean score for redness was therefore 0.33 and was fully reversible 48 hours after application.

Earlier studies for example, Mellon Institute (1969), support these findings.

RESPIRATORY IRRITATION

Severe irritation in the respiratory tract of rats and mice has been reported for vinyl acetate. For example, although no treatment-related clinical signs were reported at 50 ppm (176 mg/m³) , mice exposed at 1000 ppm (3520 mg/m³) exhibited respiratory distress throughout the treatment period (Hazleton 1980e). Similarly in rats, no clinical signs attributable to treatment were reported from the groups exposed to 50 and 200 ppm (176 and 704 mg/m³). However at 1000 ppm (3520 mg/m³), an intermittent incidence of respiratory distress was reported (Hazleton, 1980d). Refer to the acute and repeat dose toxicity sections for further detail. The conversion of ppm to mg/m³ is based on Rm of 86.09, 25 °C, 1 atmosphere.

HUMAN DATA

The only human information available is from exposed workers, who are reported to exhibit local irritant reactions of the skin, eyes and respiratory tract (Deese & Joyner,1969; EU RAR, 2008).

Effects on respiratory irritation: highly irritating

Justification for classification or non-classification

The most reliable tests (RCC, 2003a and 2003b) indicate mild irritation of the skin and eyes of rabbits that do not warrant classification. Earlier studies, of limited reliability, indicated more pronounced irritation or corrosion of skin after extended exposure periods.

However, inhalation tests with rats demonstrated severe irritation in the respiratory tract. Thus, vinyl acetate should be labelled with STOT - Single exposure Cat 3, H335 May cause respiratory irritation according to Regulation (EC) No 1272/2008.