Registration Dossier

Environmental fate & pathways

Biodegradation in water and sediment: simulation tests

Administrative data

Endpoint:
biodegradation in water: sewage treatment simulation testing
Type of information:
experimental study
Adequacy of study:
key study
Study period:
1992-07-07 to 1992-08-07
Reliability:
2 (reliable with restrictions)
Rationale for reliability incl. deficiencies:
other: Guideline study with acceptable restrictions: Distinction between elimination by biodegradation and by adsorption not possible

Data source

Reference
Reference Type:
study report
Title:
Unnamed
Year:
1992
Report Date:
1992

Materials and methods

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

Test material

Reference
Name:
Unnamed
Type:
Constituent
Details on test material:
Test substance: Isophorone diamine of Hüls AG, purity 99.9 % (area), produced 23 March 1992, ID No. 3630/81404
Radiolabelling:
no

Study design

Oxygen conditions:
aerobic
Inoculum or test system:
activated sludge, non-adapted
Details on inoculum:
INOCULUM/TEST ORGANISM
- Source: municipal WWTP Marl-West, sampled 07 Jul 1992
- Pretreatment: fed into test apparatus ca. 40 min after sampling
Duration of test (contact time):
6 d
Initial test substance concentrationopen allclose all
Initial conc.:
15.9 mg/L
Based on:
test mat.
Initial conc.:
10.1 mg/L
Based on:
DOC
Parameter followed for biodegradation estimation:
DOC removal
Details on study design:
TEST SYSTEM
- Culturing apparatus: flow-through (3 l; 0.5 l/h) - Number of culture flasks per concentration: 1 - Aeration device: pump

- Composition of synthetic waste water: 88 mg/l Pepton (Unipath) 55 mg/l meat extract (Unipath) 15 mg/l urea, CAS RN 57-13-6 3.5 mg/l sodium chloride p.a., CAS RN 7647-14-5 2 mg/l calcium chloride x 2 H2O p.a. 1 mg/l magnesium sulfate x 7 H2O p.a. 14 mg/l K2HPO4 p.a. 98 mg/l NaHCO3 (Ferak) -
Additional nutrition substrate A: 32 g/l Pepton 22 g/l meat extract 6 g/l urea 1.4 g/l sodium chloride 0.8 g/l calcium chloride x 2 H2O 0.4 g/l magnesium sulfate x 7 H2O substrate B
- 33.5 g/l K2HPO4 is stored separately - 47 g/l NaHCO3 is stored separately
- 5 ml K2HPO4 soln. + 25 ml NaHCO3 soln + 11 l tap water This soln. and nutrition substrate A (30 ml/l) are added separately

- Duration of the test:: 31 days

- Test temperature: 21.8-26.2 degree C - Other relevant factors: mean retention time 6 hours
Reference substance
Reference substance:
not required

Results and discussion

% Degradation
% Degr.:
42
Parameter:
DOC removal
Sampling time:
31 d
Transformation products:
not measured
Evaporation of parent compound:
not measured
Volatile metabolites:
not measured
Residues:
not measured
Details on results:
The mean of 19 measurements at approximately regular intervals is 42.0 +/- 5.01 % degradation

Applicant's summary and conclusion

Validity criteria fulfilled:
not specified
Conclusions:
The present study indicates that a certain amount (ca. 42 %) of the test substance may degrade in the sewage treatment plant.
Executive summary:

The present study on isophorone diamine simulates the degradation of the test substance in a sewage treatment plant and is similar or equivalent to OECD 303. The simulation study indicates that 42 % of the test item degraded within a period of 31 days. The study was assessed as "reliable with restrictions".