Registration Dossier

Environmental fate & pathways

Biodegradation in water and sediment: simulation tests

Currently viewing:

Administrative data

Endpoint:
biodegradation in water: sewage treatment simulation testing
Type of information:
experimental study
Adequacy of study:
key study
Study period:
1992-10-20 to 1992-11-26
Reliability:
2 (reliable with restrictions)
Rationale for reliability incl. deficiencies:
other: Guideline study, limited reporting but plausible

Data source

Reference
Reference Type:
study report
Title:
Unnamed
Year:
1993
Report date:
1993

Materials and methods

Test guideline
Qualifier:
according to guideline
Guideline:
OECD Guideline 303 A (Simulation Test - Aerobic Sewage Treatment. A: Activated Sludge Units)
GLP compliance:
not specified

Test material

Reference
Name:
Unnamed
Type:
Constituent
Details on test material:
Anionic surfactant
Solid 88.&%, 11.4% water
Radiolabelling:
no

Study design

Oxygen conditions:
aerobic
Inoculum or test system:
activated sludge, domestic, non-adapted
Details on inoculum:
Municipal waste water treatment plant Frankfurt-Niederrad
ca. 2.1 g dry sludge per liter in test and control unit
Duration of test (contact time):
37 d
Initial test substance concentration
Initial conc.:
24.8 mg/L
Based on:
DOC
Parameter followed for biodegradation estimation:
DOC removal
Details on study design:
Acitvated sludge unit
6h residence time
Adaptation time 6d, pH 7.8-8.2
Temperature: 22 +/- 2 deg C
NH4+ < 1 mg/L, NO2- < 1 mg/L, NO3- 50-150 mg/L
Test duration: 37d, duration of measurement: 30d, evaluation phase 17d

Results and discussion

Test performance:
no deficiencies
% Degradation
% Degr.:
62
Parameter:
DOC removal
Sampling time:
17 d
Remarks on result:
other: Degradation rate of 62% is in line with the degradation rate found in an OECD 301D and 302B test (see IUCLID Chapter 5.2.1.
Transformation products:
not specified

Applicant's summary and conclusion

Validity criteria
Validity criteria fulfilled:
yes
Conclusions:
The registration substance was tested in an OECD 303A Sewage Treatment Plant Simulation Test over 37d using a test item concentration of 24.8 mg/L. After the run-in phase the test item was monitored over 17d using 24h composite samples and DOC Analysis. Based on these measurements a Biodegradation rate of 62% +/- 3% was determined. This biodegradation rate is in line with the degradation found in a ready and in an inherent test (see IUCLID Chapter 5.2.1).