2-butyryl-3-hydroxy-5-thiocyclohexan-3-yl-cyclohex-2-en-1-one

Biodegradation in water: screening tests

Administrative data

Endpoint:

biodegradation in water: ready biodegradability

Type of information:

experimental study

Adequacy of study:

key study

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: GLP guideline study with analytical monitoring

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

1996

Report date:

1996

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

OECD Guideline 301 C (Ready Biodegradability: Modified MITI Test (I))

GLP compliance:

yes

Test material

Test material information

Constituent 1

Reference substance name:

-

EC Number:

425-150-8

EC Name:

-

Cas Number:

94723-86-1

Molecular formula:

C15 H22 O3 S

IUPAC Name:

2-butanoyl-3-hydroxy-5-(thian-3-yl)cyclohex-2-en-1-one

Details on test material:

- Name of test material (as cited in study report): 625 Triketone
- Physical state: yellowish solid
- Analytical purity: 94%
- Batch No.: LJ 27881/1

Study design

Oxygen conditions:

aerobic

Inoculum or test system:

mixture of sewage, soil and natural water

Details on inoculum:

- Source of inoculum/activated sludge: Activated sludge micro-organisms have been selected following recommendations in OECD guideline 301C. The sludge was prepared from 10 different sampling sites throughout federal state Rheinland-Pfalz, Germany:
- Domestic sewage plants of Bad-Dürkheim, Lambsheim and Weisenheim, Germany
- Industrial sewage plant of BASF
- River water samples of River Rhine near Altrip and of a river near Kleiniedesheim
- Lake water samples of lake "Große Blies" near Ludwigshafen, of lake "Silbersee" near Roxheim, of a pond near Bad-Dürkheim and of a pond near Labsheim
- Method of sampling: 1 L of activated sludge was taken from the aeration basins of each waste water treatment plant; 1 L of surface water and 1 L of aerobic soil of the banks were taken in the case of rivers and lakes
- Preparation of inoculum for exposure: Collected samples were thoroughly mixed and allowed to settle for 30 min. Floating matter was removed. About 1.7 L of the mixture were filtered. 1.5 L of the filtrate were mixed with 1.5 L filtered supernatant of the existing culture. The mixtrue was kept on a temperature range of 25 ± 2 °C and a pH range of 7.0 ± 1.0 °C.
- Concentration of sludge: 30 mg/L dry solids

Duration of test (contact time):

28 d

Initial test substance concentration

Initial conc.:

100 mg/L

Based on:

test mat.

Parameter followed for biodegradation estimation

Parameter followed for biodegradation estimation:

O2 consumption

Details on study design:

TEST SYSTEM
- Culturing apparatus: Sapromat BOD Apparatus – respirometer with a manometric coulorimetric principle. In a closed system oxygen consuption was automatically re-added by an electrolytic oxygen generator. The produced oxygen is monitored in mg/L and these BOD values are continuously stored. Carbon dioxide produced was adsorbed using soda lime pellets. Agitation of the solution was brought about by rotary stirring
- Vessels: 500 ml glass bottles
- Preparation of test assays: Determination of the suspended solids level of the activated sludge culture was carried out using 50 ml of the activated sludge culture which were carried after filtration on a filter paper until constant weight. The suspended solids concentration of the prepared activated sludge suspension was 750 mg ss/L. 10 ml of this suspension was added to each test vessel with 240 ml test medium resulting in a suspended solids loading of 30 mg ss/L
- Light regime: The cultures were shielded from light
- Number of culture flasks/concentration: 3

SAMPLING
- Sampling frequency: daily

CONTROL AND BLANK SYSTEM
- Inoculum blank: 1
- Reference substance: 1
- Abiotic control: 1

Reference substance

Reference substance:

aniline

Results and discussion

% Degradation

Parameter:

% degradation (O2 consumption)

Value:

25

Sampling time:

28 d

Details on results:

Mean degradation kinetic [%]:
Day 7: 4
Day 14: 19
Day 21: 23
Day 28: 25

Day 28 residual test material analysis (mean): 93%

Specific chemical analysis
Blank test with water: 71.3 mg/L (residual amount of test substance at end of test)
Inoculated medium: < 0.5 mg/L (residual amount of test substance at end of test)
Primary degradation (inoculated medium): 93%

BOD5 / COD results

Results with reference substance:

Concentration of aniline at start of the test: 95 mg/L (residual amount of test substance at end of test)
Concentration of aniline at the end of the test: < 0.1 mg/L (residual amount of test substance at end of test)
Primary degradation: 99%

Applicant's summary and conclusion

Interpretation of results:

other: moderately biodegradable