Registration Dossier

Administrative data

Description of key information

Key value for chemical safety assessment

Acute toxicity: via oral route

Endpoint conclusion
Dose descriptor:
LD50
Value:
1 320 mg/kg bw

Acute toxicity: via inhalation route

Endpoint conclusion
Dose descriptor:
LC50
Value:
7 100 mg/m³

Acute toxicity: via dermal route

Endpoint conclusion
Dose descriptor:
LD50
Value:
500 mg/kg bw

Additional information

Acute oral toxicity

Undiluted methacrylic acid had an LD50 of 1320 mg/kg (Paulet, 1977). Based on the corrosive properties of the substance this effect can be attributed to corrosivity rather than systemic toxicity. In two other tests, where the test material had been administered as a 25 % dilution in water (Dow, 1957) or a 10 % dilution in corn oil (Easman, 1979), the LD50 was above 2000 mg/kg in both cases.

Acute inhalation toxicity

Using a valid experimental method, the 4 hour LC50 of MAA to male and female rats was 7.1 mg/L (1983 ppm; exposure was to a mix of vapour and aerosol).

Mortality is clearly associated with exposure to aerosol. Exposure to (saturated) vapour was +/- the same at all concentration levels (3.4-3.7 mg/L). Exposure to vapour alone was not associated with mortality, while exposure to aerosol increased ( 0.9-4.7 mg/L) in parallel to an increase in mortality.

Acute dermal toxicity

In a valid screening study, the acute dermal LD50 in rabbits of MAA was 500-1000 mg/kg bw.

Justification for classification or non-classification

Acute oral toxicity

MAA is corrosive and fulfils the criteria for acute toxicity category 4 (1272/2009/EC)

Acute inhalation toxicity

Exposure to MAA vapour alone is not lethal (no classification). Exposure to MAA aerosols fulfils the criteria for acute toxicity category 4 (1272/2009/EC).

Acute dermal toxicity

The dermal toxicity (LD50 500 -1000 mg/kg) is in the range for category 3 (1272/2009/EC)