Registration Dossier
Registration Dossier
Use of this information is subject to copyright laws and may require the permission of the owner of the information, as described in the ECHA Legal Notice.
EC number: 274-581-6 | CAS number: 70356-09-1
Toxicity to microorganisms
Administrative data
Link to relevant study record(s)
Description of key information
The 3-hour NOEC (EC10) of the test item to activated sludge microorganisms was at least 1000 mg/L (i.e. the saturation concentration of the test item). This value might even be higher but concentrations above 1000 mg/L were not tested. The 3-hour EC20, EC50, and EC80 could not be calculated but were clearly higher than 1000 mg/L.
Key value for chemical safety assessment
- EC10 or NOEC for microorganisms:
- 1 000 mg/L
Additional information
The inhibitory effect of the test item Tert-butyl-4-methoxy-4’-dibenzoylmethane on the respiration rate of aerobic wastewater microorganisms of activated sludge was investigated in a 3-hour respiration inhibition test according to OECD Guideline 209 and EU Commission Directive 88/302/EEC, Part C.11. Based on the EU testing guidelines, a limit test with a nominal test concentration of 1000 mg/L was performed. In addition, two controls and three different concentrations of the reference item 3,5-dichlorophenol (5, 16, and 50 mg/L) were tested in parallel. The results of these treatments confirmed suitability of the activated sludge and the method used. At the test item concentration of 1000 mg/L, the test item was not completely dissolved in the test medium. Thus, the test concentration was clearly above the water solubility limit of Tert-butyl-4-methoxy-4’-dibenzoylmethane under the test conditions. The test item had no inhibitory effect on the respiration rate of activated sludge after the incubation period of three hours at a loading rate of 1000 mg/L. The saturation concentration (water solubility limit of Tert-butyl-4-methoxy-4’-dibenzoylmethane under the test conditions) was reached and no inhibitory effect was determined after three hours contact time. Thus, the 3-hour NOEC (EC10) of the test item to activated sludge microorganisms was at least 1000 mg/L (i.e. the saturation concentration of the test item). This value might even be higher but concentrations above 1000 mg/L were not tested. The 3-hour EC20, EC50, and EC80 could not be calculated but were clearly higher than 1000 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.
Reproduction or further distribution of this information may be subject to copyright protection. Use of the information without obtaining the permission from the owner(s) of the respective information might violate the rights of the owner.
