Registration Dossier

Data platform availability banner - registered substances factsheets

Please be aware that this old REACH registration data factsheet is no longer maintained; it remains frozen as of 19th May 2023.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

Currently viewing:

Administrative data

Link to relevant study record(s)

activated sludge respiration inhibition testing
Type of information:
experimental study
Adequacy of study:
key study
Study period:
29 Oct 1992
2 (reliable with restrictions)
Rationale for reliability incl. deficiencies:
guideline study
according to guideline
OECD Guideline 209 (Activated Sludge, Respiration Inhibition Test
according to guideline
EU Method C.11 (Biodegradation: Activated Sludge Respiration Inhibition Test)
Version / remarks:
GLP compliance:
not specified
Analytical monitoring:
Details on test solutions:
PREPARATION AND APPLICATION OF TEST SOLUTION (especially for difficult test substances)
- Method: the test item was added directly to the test vessels due to its low water solubility
Test organisms (species):
activated sludge, domestic
Details on inoculum:
- Origin: waste water treatment plant Frankfurt/M-Sindlingen, Germany
- Pretreatment: as cited in study report, sludge was pretreated according to guidelines
Test type:
Water media type:
Limit test:
Total exposure duration:
3 h
Test temperature:
20 ± 2 °C
7.2 ± 0.2
Nominal and measured concentrations:
Nominal concentrations: 500 and 1000 mg/L
Details on test conditions:
Inoculum concentration: 1600 mg/L dry weight

Reference substance (positive control):
3 h
Dose descriptor:
Effect conc.:
> 1 000 mg/L
Nominal / measured:
Conc. based on:
test mat.
Basis for effect:
inhibition of total respiration
respiration rate

The test item did not show toxic effects to microorganisms.

EC20 > 1000 mg/L

EC80 > 1000 mg/L

Validity criteria fulfilled:
not specified

Description of key information

The assessment of the toxicity of the target substance to microorganims is based on the results of the available study following OECD 209. An EC50 (3 h) > 1000 mg/L and an EC20 (3 h) > 1000 mg/L are used as key values for the CSA of the target substance. 

Key value for chemical safety assessment

Additional information

The toxicity of the Ethoxylates (AE) category substances to microorganisms was assessed by read-across based on the grouping of substances (category approach). The available data were used for a general assessment of the toxicity of the Alcohol Ethoxylates (AE) category substances to microorganisms. Based on the available data adverse effects on microbial activity are not expected. The substances of the Alcohol Ethoxylates (AE) category are readily biodegradable. In all studies conducted with a toxicity control, no inhibition of the degradation process by the test substance was observed. The available studies investigating the respiration inhibition of activated sludge organisms and Pseudomonas putida determined no detrimental effects of the tested Alcohol Ethoxylates.