Registration Dossier

Diss Factsheets

Ecotoxicological information

Short-term toxicity to aquatic invertebrates

Currently viewing:

Administrative data

Link to relevant study record(s)

Description of key information

With high probability acutely not harmful to aquatic invertebrates.

Key value for chemical safety assessment

Fresh water invertebrates

Fresh water invertebrates
Dose descriptor:
Effect concentration:
267.94 mg/L

Additional information

The acute toxicity of 1-methyl-1H-imidazole (CAS 616-47-7) to Daphnia magna was tested in a guideline study according to EU method C2. The EC0 value was determined to be 125 mg/L; the EC50 value was found to be about 267.94 mg/L after 48 h, based on nominal test concentrations (BASF AG, 1989; report no.: 1/0243/2/89-0243/89).

Even though no analytical verification of the test substance concentration was assessed, the test item can be considered as stable under test and storage conditions according to results of biodegradation and adsorption as well as physico-chemical properties such as water solubility and volatility: 1-methylimidazole is considered not readily biodegradable (according to OECD criteria), and only inherently biodegradable after a prolonged test duration (60days, BASF, 2011, 29G0492/11G077). Additionally, adsorption of 1-methylimidazole to the solid soil phase is not expected (BASF, 2021, Franco&Trapp 2008/2009/2010; BASF, 2018, KOCWIN v2.00). Furthermore, the substance is completely miscible at 20°C (1000g/L; see Ch. 4.7) and has a low vapour pressure of 0.3514 hPa at 20 °C and 0.5166 hPa at 25 °C (see Ch. 4.6).

Therefore, the substance can be regarded as stable during the 48 h test period and tested concentrations can be regarded as nominal test concentrations.


In conclusion, 1-methyl-1H-imidazole (CAS 616-47-7) is considered to be with high probability acutely not harmful to aquatic invertebrates.