Propylidynetrimethanol, propoxylated

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

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: Study was conducted in conformance to GLP and on the basis of EU Method C.11 (Biodegradation: Activated Sludge Respiration Inhibition Test), Cited as Directive 88/302/EEC, C.11

Qualifier:

according to guideline

Guideline:

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

Version / remarks:

Cited as Directive 88/302/EEC, C.11

GLP compliance:

yes (incl. QA statement)

Analytical monitoring:

no

Test organisms (species):

activated sludge of a predominantly domestic sewage

Details on inoculum:

- Laboratory culture:
- Pretreatment: Aeration, daily feed with synthetic medium; pH 7.6

Test type:

static

Water media type:

freshwater

Total exposure duration:

3 h

Remarks on exposure duration:

16.5 h was the stirring period of test item before the start of incubation

Test temperature:

20 +/- 2 °C (concerning the highest concentration of 10000 mg/l)

pH:

8.2 (concerning the highest concentration of 10000 mg/l)

Dissolved oxygen:

O2-start 5.1; O2-end 3.3 (concerning the highest concentration of 10000 mg/l)

Nominal and measured concentrations:

100, 1000 and 1000 mg/l

Details on test conditions:

TEST MEDIUM
Test concentration of the activated sludge: 480 mg/l suspended solids


OTHER TEST CONDITIONS
- Adjustment of pH: 8.2

EFFECT PARAMETERS MEASURED (with observation intervals if applicable) : respiration rate

TEST CONCENTRATIONS: 3 (100, 1000, 10000 mg/l)

Reference substance (positive control):

yes

Remarks:

3,5-Dichlorphenol (5, 10, 20 mg/l)

Duration:

3 h

Dose descriptor:

EC10

Effect conc.:

> 10 000 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

inhibition of total respiration

Remarks:

respiration rate

Propylidynetrimethanol, propoxylated showed 2.7% respiration inhibition of activated sludge at a test item concentration of 10000 mg/l, hence the EC10 > 10000 mg/l.

Conclusions:

Propylidynetrimethanol, propoxylated showed 2.7% respiration inhibition of activated sludge at a test item concentration of 10000 mg/l, hence the E10 > 10000 mg/l.

Description of key information

3 hr (domestic sludge respiration rate inhibition) EC10 is >10'000 mgl/l . No inhibition of respiration was observed.

Additional information

Toxicity to microorganisms has been tested with a sample of activated sludge from a domestic waste water treatment plant over a 3 hr period at nominal concentrations from 100 to 10'000 mgl/l. No effects were observed and the EC10 value is >10'000 mgl/l.