Registration Dossier

Administrative data

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: GLP guideline study

Data source

Reference
Reference Type:
study report
Title:
Unnamed
Year:
2006
Report Date:
2006

Materials and methods

Test guideline
Qualifier:
according to
Guideline:
OECD Guideline 209 (Activated Sludge, Respiration Inhibition Test
GLP compliance:
yes

Test material

Reference
Name:
Unnamed
Type:
Constituent
Details on test material:
- Name of test substance: MGDN
- Purity: 99.9 g/100g by 1 H-NMr spectroscopy; 99.5 area % by HPLC-fingerprint
- Chemical name: Propanenitrile, 2-[bis(cyanomethyl)amino]-
- Molecular formula: C7H8N4
- Molecular weight: 148.17 g/moL

Sampling and analysis

Analytical monitoring:
not specified

Test solutions

Vehicle:
no
Details on test solutions:
Because the test substance is sufficiently soluble in water a stock solution was prepared. For this 2000 mg of the test substance were stirred in approximately 900mL demineralised water at room temperature until the test substance was dissolved completely. After that the pH value of the stock solution was measured and adjusted to 7.5 ± 0.5. Following this the stock solution was made up to 1 L with demineralised water. The stock sotution appeared colourless-clear.

Test organisms

Test organisms (species):
activated sludge, domestic
Details on inoculum:
- Activated sludge from the municipal wastewater treatment plant of the city Mannheim/Baden Württemberg (Germany).
- lt was collected on 28 Jun 2006 from the aeration tank of the plant.
- The activated sludge Suspension was washed 3 times with tap water, sieved with a fine woven mesh (mesh size about 1 mm).
- This Suspension was adjusted to a concentration of 5.0 g/L dry weight and pre-aerated for 24 hours.
- After the pre-aeration the lost water of the suspension was replaced.
- An aliquot of this suspension was added to the test vesseis to obtain a sludge concentration of 1.0 g/L dry substance.

Study design

Test type:
static
Water media type:
freshwater
Limit test:
no
Total exposure duration:
30 min

Test conditions

Test temperature:
20 +/- 2°C
pH:
7.4
Nominal and measured concentrations:
- Test concentration (nominal): 250, 500, and 1000 mg/L
Details on test conditions:
TEST SYSTEM
- Test vessel: Erlenmeyer-vessels
- Fill volume: 250 mL
Reference substance (positive control):
yes
Remarks:
dichlorophenol

Results and discussion

Effect concentrationsopen allclose all
Duration:
30 min
Dose descriptor:
EC10
Effect conc.:
290 mg/L
Nominal / measured:
nominal
Conc. based on:
test mat.
Basis for effect:
inhibition of total respiration
Remarks:
respiration rate
Duration:
30 min
Dose descriptor:
other: EC20
Effect conc.:
620 mg/L
Nominal / measured:
nominal
Conc. based on:
test mat.
Basis for effect:
inhibition of total respiration
Remarks:
respiration rate
Duration:
30 min
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

Applicant's summary and conclusion