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Please be aware that this old REACH registration data factsheet is no longer maintained; it remains frozen as of 19th May 2023.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

Reference
Endpoint:
activated sludge respiration inhibition testing
Type of information:
read-across from supporting substance (structural analogue or surrogate)
Adequacy of study:
key study
Study period:
September, 2016 to December, 2016
Reliability:
2 (reliable with restrictions)
Rationale for reliability incl. deficiencies:
guideline study
Remarks:
Read across study
Justification for type of information:
The study with the read across substance is considered sufficient to fulfil the information requirements.
Reason / purpose for cross-reference:
read-across source
Qualifier:
according to guideline
Guideline:
EU Method C.11 (Biodegradation: Activated Sludge Respiration Inhibition Test)
GLP compliance:
yes (incl. QA statement)
Analytical monitoring:
no
Vehicle:
no
Test organisms (species):
activated sludge of a predominantly domestic sewage
Test type:
static
Water media type:
freshwater
Limit test:
no
Total exposure duration:
3 h
Nominal and measured concentrations:
Nominal: 0, 90, 170, 310, 560 and 1000 mg/L
Reference substance (positive control):
yes
Remarks:
3.5-dichlorophenol
Key result
Duration:
3 h
Dose descriptor:
EC0
Effect conc.:
592 mg/L
Nominal / measured:
nominal
Conc. based on:
test mat.
Basis for effect:
inhibition of total respiration
Key result
Duration:
3 h
Dose descriptor:
NOEC
Effect conc.:
170 mg/L
Nominal / measured:
nominal
Conc. based on:
test mat.
Basis for effect:
inhibition of total respiration
Validity criteria fulfilled:
yes
Conclusions:
Under the study conditions, a nominal 3 h EC50 of 592 mg/L based on total oxygen uptake inhibition was found for the test substance. The nominal 3 h NOEC was equivalent to 170 mg/L.
Executive summary:

A study was conducted to determine the effect of the read across substance, vinyl toluene, on the respiration rate of activated sludge according to EU Method C11, in compliance with GLP. Based on the results of a preliminary study, activated sludge from a municipal wastewater treatment plant was exposed to the substance at 5 nominal concentrations ranging from 90 to 1000 mg/L. Six blank controls, three at the beginning and three at the end of the test were also included. 3,5-dichlorophenol was used as a reference substance at 5, 10 and 20 mg/L. Abiotic decomposition was not detected in the preliminary study , therefore no abiotic control was included in the main study. All criteria of acceptability were fulfilled and the study was considered valid. Under the study conditions, a nominal 3 h EC50 of 592 mg/L based on total oxygen uptake inhibition was found for the test substance. The nominal 3 h NOEC was equivalent to 170 mg/L (Nachtigallova, 2016).

Description of key information

Key value for chemical safety assessment

EC50 for microorganisms:
592 mg/L
EC10 or NOEC for microorganisms:
170 mg/L

Additional information

A study was conducted to determine the effect of the read across substance, vinyl toluene, on the respiration rate of activated sludge according to EU Method C11, in compliance with GLP. Based on the results of a preliminary study, activated sludge from a municipal wastewater treatment plant was exposed to the substance at 5 nominal concentrations ranging from 90 to 1000 mg/L. Six blank controls, three at the beginning and three at the end of the test were also included. 3,5-dichlorophenol was used as a reference substance at 5, 10 and 20 mg/L. Abiotic decomposition was not detected in the preliminary study , therefore no abiotic control was included in the main study. All criteria of acceptability were fulfilled and the study was considered valid. Under the study conditions, a nominal 3 h EC50 of 592 mg/L based on total oxygen uptake inhibition was found for the test substance. The nominal 3 h NOEC was equivalent to 170 mg/L (Nachtigallova, 2016).