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Description of key information

Dicarboxylic acid mixture is of low acute toxicity after oral or dermal exposure. Although no reliable inhalation study is available low toxicity by inhalation is also anticipated based on low acute toxicity data reported for adipic acid.

Key value for chemical safety assessment

Acute toxicity: via oral route

Endpoint conclusion
Dose descriptor:
LD50
Value:
6 000 mg/kg bw

Acute toxicity: via dermal route

Endpoint conclusion
Dose descriptor:
LD50
Value:
7 940 mg/kg bw

Additional information

An oral LD50 value of 6000 mg/kg (95% confidence limits 5400 - 6720 mg/kg) was reported in rats in a study similar to OECD TG 401 with doses up to 10000 mg/kg. In this study a 20% aqueous solution of a dicarboxylic acid mixture was tested and mortality was seen during the first 4 days; most deaths were reported within the first day. Signs of intoxication were weight loss (one day in survivors), increased weakness, salvation, collapse and death. Lethal doses caused hemorrhagic lungs, liver, kidney and spleen discoloration and acute gastrointestinal inflamation. Animals that survived to termination (day 14) appeared normal (Birch 1979). Two additional studies report LD50 values of 5000 mg/kg and 2207 mg/kg and support the low acute oral toxicity of dicarboxylic acid mixture.

No mortality was reported in an acute dermal toxicity experiment in rabbits following administration of 5010 mg/kg (n=1) or 7940 mg/kg (n=2) of a 40% aqueous solution/suspension of dicarboxylic acid mixture. The only clinical signs reported were weight loss during the first 2 to 4 days. The viscera appeared normal at termination after 14 days.

There are no reliable data available to evaluate the acute inhalation toxicity of dicarboxylic acid mixture. Reliable data are only available for adipic acid. In a study similar to OECD TG 403 no mortality, toxicity or macroscopic pathological changes were observed in 20 rats exposed for 4 h (nose only) to the maximal attainable concentration of 7700 mg/m3 of adipic acid dust. 50% of the particles had a MMAD below 3.5 µm.

Additional sources/reviews cited in chapter "Additional Toxicological Information" support that dicarboxylic acid mixture is of low acute toxicity by the oral, dermal and inhalation route.

Justification for classification or non-classification

No classification is required according to the classification criteria 67/548/EWG and EU regulation no. 1272/2008 (GHS).