Alcohols, C20-22, reaction products with phosphorus oxide (P2O5)

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:

August -September 2008

Reliability:

1 (reliable without restriction)

Qualifier:

according to guideline

Guideline:

OECD Guideline 209 (Activated Sludge, Respiration Inhibition Test

GLP compliance:

yes (incl. QA statement)

Specific details on test material used for the study:

Details on properties of test surrogate or analogue material (migrated information):
PHYSICO-CHEMICAL PROPERTIES
- Melting point: 70-75°C
- Boiling point: >300°C
- Vapour pressure: 6.66 x 10-5 Pa.
- Water solubility (under test conditions): <1mg/L



OTHER PROPERTIES (if relevant for this endpoint)
- Results of test for ready biodegradability: not considered as ready biodegradable

Analytical monitoring:

yes

Test organisms (species):

activated sludge of a predominantly domestic sewage

Limit test:

yes

Total exposure duration:

3 h

Test temperature:

21 +-1°C

pH:

7.6 to 7.9

Dissolved oxygen:

2.2 to 2.5 mg/L

Nominal and measured concentrations:

1000mg/L

Reference substance (positive control):

yes

Remarks:

3,5 dichlorophenol

Duration:

3 h

Dose descriptor:

EC50

Effect conc.:

> 1 000 mg/L

Nominal / measured:

meas. (initial)

Duration:

3 h

Dose descriptor:

NOEC

Effect conc.:

1 000 mg/L

Nominal / measured:

meas. (initial)

Conc. based on:

test mat.

Results with reference substance (positive control):

The reference material gave a 3 -Hour EC50 value of 8.6mg/L, 95% confidence limits 6.7 -11mg/L.

A study was performed to asses the effect of the test material on the respiration of activated sewage sludge. The method followed that described in the OECD guidelines for testing of chemicals (1984) N° 209 "activated sludge, inhibition respiration test" method C11 of EEC commission directive 88/302/EEC and US EPA drafts ecological effects test guidelines OPPTS 850.6800.

Following a preliminary range finding test, activated sewage sludge was exposed to an aqueous dispersion of the test material at a concentration of 1000mg/L (three replicate flasks) for a period of 3 hours at a temperature of approximately 21°C with the addition of a synthetic sawage as respiratory substrate.

The rate of respiration was determined after 30 minutes and 3 Hours contact time and compared to data for the control and a reference material 3,5 dichlorophenol.

The result of the test material on the respiration of activated sewage sludge gave a 3-hours EC50 of greater than 1000mg/L. The No Observed Effect Concentration (NOEC) after 3 Hours exposure was 1000mg/L.

It was considered unnecessary and unrealistic to test at concentrations in excess of 1000mg/L.

The reference material gave a 3 -Hour EC50 value of 8.6mg/L, 95% confidence limits 6.7 -11mg/L.

Validity criteria fulfilled:

yes

Conclusions:

The effect ot the test material on the respiration of activated sewage sludge micro-organisms gave an 3-hour EC50 of greater than 1000mg/L. the No Observed Effect Concentration after 3 hours of exposure was 1000mg/L.

Executive summary:

A study was performed to asses the effect of the test material on the respiration of activated sewage sludge. The method followed that described in the OECD guidelines for testing of chemicals (1984) N° 209 "activated sludge, inhibition respiration test" method C11 of EEC commission directive 88/302/EEC and US EPA drafts ecological effects test guidelines OPPTS 850.6800.

Following a preliminary range finding test, activated sewage sludge was exposed to an aqueous dispersion of the test material at a concentration of 1000mg/L (three replicate flasks) for a period of 3 hours at a temperature of approximately 21°C with the addition of a synthetic sawage as respiratory substrate.

The rate of respiration was determined after 30 minutes and 3 Hours contact time and compared to data for the control and a reference material 3,5 dichlorophenol.

The result of the test material on the respiration of activated sewage sludge gave a 3-hours EC50 of greater than 1000mg/L. The No Observed Effect Concentration (NOEC) after 3 Hours exposure was 1000mg/L.

It was considered unnecessary and unrealistic to test at concentrations in excess of 1000mg/L.

The reference material gave a 3 -Hour EC50 value of 8.6mg/L, 95% confidence limits 6.7 -11mg/L.

Description of key information

A study was performed to asses the effect of the registered substance on the respiration of activated sewage sludge. The method followed that described in the OECD guidelines for testing of chemicals (1984) N° 209 "activated sludge, inhibition respiration test" method C11 of EEC commission directive 88/302/EEC and US EPA drafts ecological effects test guidelines OPPTS 850.6800.

The result of the registered substance on the respiration of activated sewage sludge gave a 3-hours EC50 of greater than 1000mg/L. The No Observed Effect Concentration (NOEC) after 3 Hours exposure was 1000mg/L.

Key value for chemical safety assessment

EC10 or NOEC for microorganisms:

1 000 mg/L