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Please be aware that this old REACH registration data factsheet is no longer maintained; it remains frozen as of 19th May 2023.

The new ECHA CHEM database has been released by ECHA, and it now contains all REACH registration data. There are more details on the transition of ECHA's published data to ECHA CHEM here.

Diss Factsheets

Ecotoxicological information

Toxicity to microorganisms

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Administrative data

Link to relevant study record(s)

Description of key information

The inhibition of ammonia comsumption was used as parameter for toxic  inhibition of Nitrosomonas by ethylbenzene and the 24 hour EC50 was 96 mg/l.

Key value for chemical safety assessment

EC50 for microorganisms:
96 mg/L

Additional information

The inhibition of ammonia consumption was used as parameter for toxic inhibition of the nitrifying organism, Nitrosomonas, by ethylbenzene and the 24 hour EC50 was 96 mg/L. 

 

Ethylbenzene was evaluated in activated sludge, respiration inhibition test using an activated sludge (domestic) in two separate studies.  In the 1st study, the test procedure was designed to mimic the standard ATA using heterotrophic cultures under aerobic conditions. All tests were carried out in sealed serum bottles to prevent the loss of volatile chemicals. The inhibition of oxygen uptake was determined as criterion for the toxic inhibition of the aerobic activated sludge under the conditions of the study, the EC50 was 130 mg/L. In a second study ethylbenzene was evaluated in activated sludge, respiration inhibition test using an activated sludge (domestic) and under the conditions of the study, the EC50 was around 600 mg/L.

 

Anaerobic toxicity assays (ATA) were conducted using an enrichment culture that had been maintained in the laboratory.  Under the conditions of the test, the 48 hour EC50 was 160 mg/L.

Along with the key study, 12 supporting studies have been included or the toxicity of ethylbenzene to microorganisms together with 6 studies considered unreliable (Klimisch score 3).