(Z)-9-Octadecen-1-ol ethoxylated

Toxicity to microorganisms

Link to relevant study record(s)

Reference

Endpoint:

activated sludge respiration inhibition testing

Type of information:

experimental study

Adequacy of study:

key study

Study period:

29 Oct 1992

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

OECD Guideline 209 (Activated Sludge, Respiration Inhibition Test

Qualifier:

according to guideline

Guideline:

EU Method C.11 (Biodegradation: Activated Sludge Respiration Inhibition Test)

Version / remarks:

(1988)

GLP compliance:

not specified

Analytical monitoring:

no

Vehicle:

no

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:

static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

3 h

Test temperature:

20 ± 2 °C

pH:

7.2 ± 0.2

Nominal and measured concentrations:

Nominal concentrations: 500 and 1000 mg/L

Details on test conditions:

TEST SYSTEM
Inoculum concentration: 1600 mg/L dry weight

Reference substance (positive control):

yes

Remarks:

3,5-Dichlorphenol

Duration:

3 h

Dose descriptor:

EC50

Effect conc.:

> 1 000 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

inhibition of total respiration

Remarks:

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. 

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.