Blue MGi 1037-Na (notification presscake)

Toxicity to microorganisms

Link to relevant study record(s)

Reference

Reference 1

Endpoint:

activated sludge respiration inhibition testing

Type of information:

experimental study

Adequacy of study:

key study

Study period:

from 2000-06-27 to 2000-10-30

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

OECD Guideline 209 (Activated Sludge, Respiration Inhibition Test (Carbon and Ammonium Oxidation))

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Analytical monitoring:

no

Vehicle:

no

Test organisms (species):

activated sludge

Limit test:

no

Total exposure duration:

3 h

Duration:

3 h

Dose descriptor:

other: EC20

Effect conc.:

> 1 000 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

inhibition of heterotrophic respiration

Key result

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 heterotrophic respiration

Duration:

3 h

Dose descriptor:

other: EC80

Effect conc.:

> 1 000 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

inhibition of heterotrophic respiration

Validity criteria fulfilled:

yes

Conclusions:

The 3-hour EC20, EC50 and EC80 could not be calculated, but were clearly higher than 1000 mg/L.

Executive summary:

The inhibitory effect of the test item BLUE MGi 1037 on the respiration rate of aerobic wastewater microorganisms of activated sludge was investigated in a 3-hour respiration inhibition test according to the Commission Directive 87/302/EEC, and the OECD Guideline for Testing of Chemicals, No. 209. The following nominal concentrations of BLUE MGi 1037 were tested: 10, 32, 100, 320 and 1000 mg/L. Concentrations in excess of nominal 1000 mg/L were not tested.

In addition, two controls and three different concentrations of the reference item 3,5 dichlorophenol (5, 16 and 50 mg/L) were tested in parallel. The results of these treatments confirmed suitability of the activated sludge and the method used. Up to and including the concentration of nominal 1000 mg/L the test item BLUE MGi 1037 had no significant inhibitory effect (<15%) on the respiration rate of activated sludge after the incubation period of three hours. The inhibition of the respiration rates was in the range of 1.5 to 9.1% compared to the controls. Thus, the 3-hour NOEC of BLUE MGi 1037 to activated sludge microorganisms was at least 1000 mg/L. This value might be even higher, but concentrations in excess of 1000 mg/L were not tested. The 3-hour EC20, EC50 and EC80 could not be calculated, but were clearly higher than 1000 mg/L.

Reference 2

Endpoint:

activated sludge respiration inhibition testing

Type of information:

read-across from supporting substance (structural analogue or surrogate)

Adequacy of study:

key study

Reason / purpose for cross-reference:

read-across source

Key result

Duration:

3 h

Dose descriptor:

EC50

Effect conc.:

> 1 000 mg/L

Nominal / measured:

nominal

Description of key information

Under the conditions of the performed Activated Sludge Respiration Inhibition Test, the 3-hour NOEC of the structural analogue substance Blue MGi 1037 to activated sludge microorganisms was at least 1000 mg/L. This value might be even higher, but concentrations in excess of 1000 mg/L were not tested. The 3-hour EC20, EC50 and EC80 could not be calculated, but were clearly higher than 1000 mg/L.

Key value for chemical safety assessment

EC50 for microorganisms:

1 000 mg/L

Additional information

The inhibitory effect of the test item BLUE MGi 1037 on the respiration rate of aerobic wastewater microorganisms of activated sludge was investigated in a 3-hour respiration inhibition test according to the Commission Directive 87/302/EEC, and the OECD Guideline for Testing of Chemicals, No. 209. The following nominal concentrations of BLUE MGi 1037 were tested: 10, 32, 100, 320 and 1000 mg/L. Concentrations in excess of nominal 1000 mg/L were not tested.

In addition, two controls and three different concentrations of the reference item 3,5 dichlorophenol (5, 16 and 50 mg/L) were tested in parallel. The results of these treatments confirmed suitability of the activated sludge and the method used.Up to and including the concentration of nominal 1000 mg/L the test item BLUE MGi 1037 had no significant inhibitory effect (<15%) on the respiration rate of activated sludge after the incubation period of three hours. The inhibition of the respiration rates was in the range of 1.5 to 9.1% compared to the controls. Thus, the 3-hour NOEC of BLUE MGi 1037 to activated sludge microorganisms was at least 1000 mg/L. This value might be even higher, but concentrations in excess of 1000 mg/L were not tested. The 3-hour EC20, EC50 and EC80 could not be calculated, but were clearly higher than 1000 mg/L.