Registration Dossier

Administrative data

Description of key information

Oral 
LD50 rat: ca. 7900 mg/kg bw (Deichmann 1941)
Inhalation
LC50 rat, 4 h exposition: 29.8 mg/L (Tansy et al. 1980)
Dermal
LD50 rat, 24 h, occlusive conditions: >5000 mg/kg bw

Key value for chemical safety assessment

Acute toxicity: via oral route

Endpoint conclusion
Dose descriptor:
LD50
7 900 mg/kg bw

Acute toxicity: via inhalation route

Endpoint conclusion
Dose descriptor:
LC50
29 800 mg/m³

Acute toxicity: via dermal route

Endpoint conclusion
Dose descriptor:
LD50
5 000 mg/kg bw

Additional information

There are reliable data available to assess the acute toxicity of methyl methacrylate.

 

Oral

Results of various studies indicate a very low acute toxic potential of methyl methacrylate for the most common test species after oral application: the lowest valid LD50 values were 7900 mg/kg bw and 9400 mg/kg bw in rats (Deichmann 1941; Spealman 1945).

The studies were performed before GLP and OECD guidelines were established and therefore only basic data were available. However, they are broadly consistent with data obtained in other species and with other esters in the category of lower alkyl methacrylate esters and, therefore, the entire data base provided sufficient information to assess the acute oral toxicity.

Inhalation

The acute toxic potential of methyl methacrylate after inhalation exposure in rats is low (LC50 = 29.8 mg/L 4 h exposure; corresponding to 7093 ppm; Tansy et al. 1980)

 

The study was performed before GLP and OECD guidelines were established and therefore only basic data were available. However, they are broadly consistent with data obtained in other species and with other esters in the category of lower alkyl methacrylate esters and, therefore, the entire data base provided sufficient information to assess the acute inhalation toxicity.

 

Dermal

There is one valid study available reporting a LD50 value in rabbits comparable to OECD guideline 402 (Rohm & Haas 1982). The undiluted test substance was applied to the clipped skin of two New Zealand White rabbits per dose for 24 h under occlusive conditions. Even under these harsh conditions, no mortality, clinical signs or pathological findings were observed and the LD50 was therefore assessed to be >5000 mg/kg bw.

The study was performed before GLP and OECD guidelines were established and therefore only basic data were available. However, they are broadly consistent with data obtained in other species and with other esters in the category of lower alkyl methacrylate esters and, therefore, the entire data base provided sufficient information to assess the acute dermal toxicity.

Other routes

There are studies for toxicity using other routes of exposure (i.p.,) using different species which are not considered being relevant for the assessment.

 

Justification for classification or non-classification

Based on the results of the available studies, methyl methacrylate is not required to be classified for its acute toxicity potential according to 67/548/EEC and CLP/EU-GHS requirements, respectively.

Under UN-GHS, MMA falls into category 5 for acute inhalation toxicity - with no classification for the dermal and oral routes.