Registration Dossier

Ecotoxicological information

Toxicity to microorganisms

Currently viewing:

Administrative data

Link to relevant study record(s)

Description of key information

OECD 209, activated sludge: EC50: 383 mg/L
Microtox test with Photobacterium phosphoreum: EC50(15min): 0.21 % (2100 mg/L)

Key value for chemical safety assessment

EC50 for microorganisms:
383 mg/L

Additional information

The toxicity of 4-phenylbutenone towards aquatic microorganisms was investigated according to ISO 8192, which corresponds in most parts to OECD Guideline 209 (Kanne, 1993). A defined volume of activated sludge is mixed with synthetic culture medium and incubated. The respiration rate was measured during this time and compared to inoculums with different test substance respiration rates. 3,5-Dichlorphenole is used as reference compound. The activated sludge was not pretreated before. Test concentrations of 56, 100, 180, 320 and 560 mg/L were used. As result, an EC50 of 383 mg/L was reported, which corresponds to a nominal concentration since no analytical monitoring was conducted.

Further information is given as followed: Brorson et al. (1994) investigated the potential environmental impact of wastewater from a chemical-pharmaceutical plant. For this purpose, the test substance was investigated in a mixture for its potential to inhibit nitrification (according to ISO/DIS 9509) and respiration (according to Danish standard DS297). Furthermore, a Microtox test was conducted, whereby marine luminescence bacteria Photobacterium phosphoreum was exposed for 15 minutes to the test substance and the resulting EC50 value of 0.21 % corresponds to the concentration at which the luminosity of the bacteria decreases by 50 %.