Guanidine, N-phenyl-, compd. with carbonic acid, hydrate (2:1:2)

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:

July - August 1992

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

Deviations:

yes

Remarks:

In deviation from the Guideline settled sludge instead of centrifugated sludge was used.

GLP compliance:

yes

Remarks:

This study has been performed in compliance with GLP in Switzerland, Procedures and Principles, March 1986, issued by the Swiss federal Department of the Interior and the Intercantonal Office for the Control of Medicaments.

Analytical monitoring:

not required

Vehicle:

no

Test organisms (species):

activated sludge

Test type:

static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

3 h

Key result

Duration:

3 h

Dose descriptor:

EC50

Effect conc.:

64.2 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

inhibition of total respiration

Remarks:

respiration rate

Duration:

3 h

Dose descriptor:

other: EC20

Effect conc.:

7.3 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

inhibition of total respiration

Remarks:

respiration rate

Duration:

3 h

Dose descriptor:

EC100

Effect conc.:

> 100 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

inhibition of total respiration

Remarks:

respiration rate

Validity criteria fulfilled:

yes

Remarks:

The two control respiration rates are within 15 % of each other and the EC50 (3h) of 3,5-Dichlorphenol is in the accepted range 5 to 30 mg/l

Conclusions:

EC50 (3h) = 64.2 mg/L
EC20 (3h) = 7.3 mg/L
EC100 (3h) > 100 mg/L

Executive summary:

The toxicity of CA 1139 A to activated sludge was determined in a 3-hours respiration inhibition test, according to GLP Guideline OECD 209, under aerobic conditions at room temperature (20 +/-2 ºC). The experiment was conducted in compliance with Good Laboratory Practice (GLP) in, Procedures and Principles, March 1986, issued by the Federal Department of the interior and the Intercantonal Office for the Control of Medicaments.

The test substance concentrations tested were 100.3, 32.1, 10.0, 3.2 and 1.0 mg/l. The reference substance 3,5-Dichlorophenol was tested in concentrations of 32, 10 and 3.2 mg/l. 

The test system consisted of activated sludge collected from a communal sewage treatment plant. 1.69 g/l sludge (dry weight) was used.

The respiration rate of the activated sludge fed with a standard amount of synthetic sewage feed was measured (ORION – Electrode Type 97-08, ORION Microprocessor Ionalizer 901) after a contact time of 3 hours with the test substance. The reference substance 3,5-Dichlorophenol and a blank (synthetic sewage feed, inoculum and water) served as controls.

 

The following values have been graphically determined:

EC50 (3h) = 64.2 mg/L

EC20 (3h) =  7.3 mg/L

EC100 (3h) > 100 mg/L

The results are based on nominal concentrations. 

 

Description of key information

The toxicity of CA 1139 A to activated sludge was determined in a 3-hours respiration inhibition test,

according to GLP Guideline OECD 209, under aerobic conditions at room temperature (20 +/-2 ºC). The experiment was conducted in compliance with Good Laboratory Practice (GLP) in, Procedures and Principles, March 1986, issued by the Federal Department of the interior and the Intercantonal Office for the Control of Medicaments.
The test substance concentrations tested were 100.3, 32.1, 10.0, 3.2 and 1.0 mg/l. The reference substance 3,5-Dichlorophenol was tested in concentrations of 32, 10 and 3.2 mg/l.
The test system consisted of activated sludge collected from a communal sewage treatment plant. 1.69 g/l sludge (dry weight) was used.
The respiration rate of the activated sludge fed with a standard amount of synthetic sewage feed was measured (ORION – Electrode Type 97-08, ORION Microprocessor Ionalizer 901) after a contact time of 3 hours with the test substance. The reference substance 3,5-Dichlorophenol and a blank (synthetic sewage feed, inoculum and water) served as controls.
The following values have been graphically determined:
EC50 (3h) = 64.2 mg/L
EC20 (3h) = 7.3 mg/L
EC100 (3h) > 100 mg/L
The results are based on nominal concentrations.

Key value for chemical safety assessment

EC50 for microorganisms:

64.2 mg/L

Additional information

   

Guideline Test Type	Species	Results	Reference	Reliability
OECD 209	activated sludge of a communal sewage treatment plant	EC50(3h) = 64.2 mg/l EC20(3h) = 7.3 mg/L EC100(3h) > 100 mg/L	Ciba-Geigy Ltd., Baumann, W.; 1992	Reliable without restriction