Registration Dossier
Registration Dossier
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EC number: 202-506-9 | CAS number: 96-45-7
Toxicity to aquatic algae and cyanobacteria
Administrative data
Link to relevant study record(s)
Description of key information
The acute toxicity of Imidazolidine-2-thione (ETU)was evaluated with P.subcapitata in a study performed in accordance with OECD testing guideline 201 and GLP requirements. As no effect was observed during the preliminary test, a limit test was performed. The algae were exposed to nominal test concentration of 100 mg/L under static conditions during 72 hours. EC50 -72h was estimated using measured concentrations as being > 100 mg/L. NOEC was therefore set at 100 mg/L.
Key value for chemical safety assessment
- EC10 or NOEC for freshwater algae:
- 100 mg/L
Additional information
The toxicity of ETU for aquatic algae was evaluated for two species.
The acute toxicity of ETU was evaluated with C.pyrenoidosa in a study performed in accordance with no guideline.
The algae were exposed to nominal test concentrations under static conditions during 96 hours.
EC50-96h was estimated using measured concentrations as being equal to 6600 mg/L. Nevertheless, this value has to be taken with caution because it was estimated based upon data obtained after a 4h-incubation period.
The acute toxicity of ETU was evaluated with P.subcapitata in a study performed in accordance with OECD testing guideline 201 and GLP requirements. As no effect was observed during the preliminary test, a limit test was performed. The algae were exposed to nominal test concentration of 100 mg/L under static conditions during 72 hours. EC50 -72h was estimated using measured concentrations as being > 100 mg/L. NOEC was therefore set at 100 mg/L.Information on Registered Substances comes from registration dossiers which have been assigned a registration number. The assignment of a registration number does however not guarantee that the information in the dossier is correct or that the dossier is compliant with Regulation (EC) No 1907/2006 (the REACH Regulation). This information has not been reviewed or verified by the Agency or any other authority. The content is subject to change without prior notice.
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