Registration Dossier

Diss Factsheets

Ecotoxicological information

Toxicity to microorganisms

Currently viewing:

Administrative data

Link to relevant study record(s)

Description of key information

Toxicity to microorganisms has been assessed for two substances that would fall within the MDI category definition. In both studies IL50 values were determined to be greater than the highest nominal loading rate, with NOELR values at the highest loading rate. Based on these results, members of the MDI category are not expected to be toxic to microorganisms at the limit of solubility.

Key value for chemical safety assessment

Additional information

Studies were performed to assess the toxicity of 3,3'-dicyclohexyl-1,1'-methylenebis(4,1-phenylene)diurea (EC 406-370-3), and N,N''-(methylenedi-4,1-phenylene)bis[N'-octyl]urea (EC 445-760-8), to microorganisms. The study conducted with 3,3'-dicyclohexyl-1,1'-methylenebis(4,1-phenylene)diurea (EC 406-370-3), was designed to be compliant with the guideline 87/302/EEC. The microorganisms were exposed to the test item for 0.5 hours under aerobic conditions. The IL50 at the end of the test was greater than 100 mg/L and the NOELR was 100 mg/L, the highest test concentration. The study conducted with N,N''-(methylenedi-4,1-phenylene)bis [N'-octyl]urea (EC 445-760-8), was designed to be compliant with the OECD 209 guideline. The microorganisms were exposed to the test item for 3 hours under aerobic conditions. The derived IL50 at the end of the test were greater than 1000 mg/L and the NOELR was 1000 mg/L, the highest tested loading rate.