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Administrative data

Description of key information

The LD50/LC50 values derived from the key-studies were: LD50 (oral, rat) > 5000 mg/kg bw and LC50 (rat, inhal.) > 8.4 g/m³.

Key value for chemical safety assessment

Acute toxicity: via oral route

Endpoint conclusion
Dose descriptor:
5 000 mg/kg bw

Acute toxicity: via inhalation route

Endpoint conclusion
Dose descriptor:
8 400 mg/m³

Additional information

Acute toxicity: oral

The acute oral toxicity of 2-Methylpentanal in the rat was examined according to OECD TG 423 and GLP (ARC, 2008).Two groups of 3 female rats were treated at a dose of 2000 mg/kg bw by oral gavage. During the 14-day observation period neither mortality nor clinical signs were noted. Body weight development was not impaired and no changes were observed at necropsy. As no mortality occurred at 2000 mg/kg bw a LD50 > 5000 mg/kg bw can be assumed acc. to OECD TG 423. This is supported by an older oral toxicity study in the rat (BASF AG, 1977) where a LD50 of ca. 6400 mg/kg bw was determined.


Acute toxicity: inhalation

In an acute inhalation study following the principles of OECD TG 403 groups of 10 rats per sex were whole body exposed to 8.4 mg 2-Methylpentanal/L (analytically measured) for 4 h and subsequently observed for 14 days (BASF AG, 1978). All animals survived. As clinical signs accelerated respiration, crusted noses and rough fur occurred. No animal showed any abnormal finding at necropsy. Body weight development was not impaired.

Consequently, a LC50 > 8.4 mg/L air was determined. In a supporting study no mortality of rats was observed in an atmosphere enriched with the test substance at 20 °C (vapor) after an exposure of 8 hours (BASF, 1977).

Justification for classification or non-classification

Based on the results for acute oral (LD50 rat > 5000 mg/kg bw) and inhalation toxicity (LC50 > 8.4 mg/L), 2-Methylpentanal is not subject for classification according to Directive 67/548/EEC and Regulation 1272/2008/EC.