Registration Dossier

Administrative data

Description of key information

Skin irritation
Human data
Patch test study with volunteers: 18/20 showed erythema and dermatitis after exposure to 5% methyl methacrylate in paraffin or olive oil (Nyquist 1958). Although a clear distinction between sensitisation and irritation is difficult and the exposure period is far longer than usual in irritation testing the results suggest that MMA may have the potential for skin irritation in humans.
Animal data
in vivo, rabbit: low to moderate potential for skin irritation (Sterner 1977; Rohm & Haas 1982)
Eye irritation
Animal data
in vivo, rabbit, 0.1 mL, unwashed: no potential for eye irritation (Sterner 1978, Rohm and Haas 1982)
Irritation of the respiratory tract
Human data
Workplace exposure: acute and reversible irritation at concentration levels exceeding 100 ppm (ca. 0.410 mg/L; (Coleman, 1963, Roehm 1994, Muttray et al., 1997, Muttray et al., 2007)

Key value for chemical safety assessment

Skin irritation / corrosion

Endpoint conclusion
Endpoint conclusion:
adverse effect observed (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

There was valid in vivo information available to assess the potential for skin and eye irritation of methyl methacrylate.

Skin irritation

Human data

Nyquist et al.(1958) reported erythema and eczematous dermatitis in 18/20 human volunteers to methyl methacrylate (5% in paraffin or olive oil). Although a clear distinction between sensitisation and irritation was not made by the author and the exposure period is far longer than usual in irritation testing the results suggest that MMA may have the potential for skin irritation in humans.

Animal data

The results of the reliable studies varied. In the most reliable study (standardized test protocol according to the Draize test, 0.5 mL of the unchanged test substance were applied to shaved skin sites of six New Zealand White rabbits under occlusive conditions for 24 hours), only slight erythema were observed in 1/6 animals in the 24 h reading; no further effects were observed. The mean erythema and oedema scores were 0.08 and 0.00 for all animals and readings, respectively (Sterner 1977). On the other hand, Rohm and Haas (1982) reported moderate skin irritation after application of 0.5 mL of the test substance to the rabbit skin under occlusive conditions for 4/24 hours. In an overall view it is considered that methyl methacrylate possess the potential for skin irritation.

 

Eye irritation

Animal data

Here, the results of the reliable studies produced a clear pattern. In the most reliable study, 0.1 mL of the unchanged test substance was applied to the eyes of six New Zealand White rabbits and the treated eyes were not washed out (Sterner 1978). In the relevant reading period between 24 h and 72 h after application there were no irritation effects observed on cornea, iris and conjunctivae (redness and chemosis). The respective mean scores were 0.0 for all parameters. Slight to moderate conjunctivae redness, chemosis and discharge was observed in the readings 1 h to 8 h after application, which were not relevant for classification.In addition, slight, transient effects were described in a study of Rohm & Haas (1982). Overall it is considered that methyl methacrylate possess the potential for, at most, slight irritation effects on the rabbit eye.

 

Irritation of the respiratory tract

Human data

Reversible irritation reactions have been observed after short-term peak exposures to humans at concentration levels exceeding 100 ppm (Coleman, 1963, Roehm 1994). No damage to olfactory function was reported in a cross-sectional smell test in workers exposed to MMA up to 50 ppm during the past 6 years and up to 100 ppm the time before (mean duration of exposure 9.6 years) (Muttray et al., 1997). No effects were seen after single exposures to 50 ppm in a study with human volunteers investigating changes in cytokine levels indicative of subclinical, irritating effects (Muttray et al., 2007)


Effects on skin irritation/corrosion: irritating

Effects on respiratory irritation: irritating

Justification for classification or non-classification

Skin irritation

The results of the reliable animal studies varied between slight and moderate, reversible irritation effects on the rabbit skin. There are also indications of irritation in human patch tests with prolonged exposure. Hence, methyl methacrylate is classified as a skin irritant (R38 and skin irritation Cat. 2 according to 67/548/EEC and UN-GHS criteria, respectively).

Eye irritation

It is considered that methyl methacrylate possess the potential for maximum slight irritation effects on the rabbit eye, which were below the criteria for classification according to 67/548/EEC and UN-GHS criteria, respectively. No classification.

Irritation of the respiratory tract

Based on results of studies in humans and animals methyl methacrylate has to be classified as irritant to the respiratory tract (R37 and STOT single exposure Cat. 3 according to 67/548/EEC and UN-GHS criteria, respectively).