2,6,6-trimethylcyclohex-2-ene-1,4-dione

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: Guideline study with GLP

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 A (Ready Biodegradability: DOC Die Away Test)

GLP compliance:

yes

Test material

Test material information

Constituent 1

Reference substance name:

2,6,6-trimethylcyclohex-2-ene-1,4-dione

EC Number:

214-406-2

EC Name:

2,6,6-trimethylcyclohex-2-ene-1,4-dione

Cas Number:

1125-21-9

Molecular formula:

C9H12O2

IUPAC Name:

2,6,6-trimethylcyclohex-2-ene-1,4-dione

Details on test material:

- Name of test material (as cited in study report): Oxoisophorone (2,6,6-Trimethylcyclohex-2-ene-1,4-dione)
- Analytical purity: > 98 %

Study design

Oxygen conditions:

aerobic

Inoculum or test system:

activated sludge, domestic (adaptation not specified)

Details on inoculum:

- Source of inoculum/activated sludge (e.g. location, sampling depth, contamination history, procedure): activated sludge taken from a WWTP treating municipal sewage.

Duration of test (contact time):

28 d

Initial test substance concentration

Initial test substance concentration 1

Initial conc.:

20 mg/L

Based on:

DOC

Initial test substance concentration 2

Initial conc.:

27.6 mg/L

Based on:

test mat.

Parameter followed for biodegradation estimation

Parameter followed for biodegradation estimation:

DOC removal

Details on study design:

TEST CONDITIONS
- Composition of medium:
- Additional substrate:
- Solubilising agent (type and concentration if used):
- Test temperature:
- pH:
- pH adjusted: yes/no
- CEC (meq/100 g):
- Aeration of dilution water:
- Suspended solids concentration:
- Continuous darkness: yes/no
- Other:

TEST SYSTEM
- Culturing apparatus:
- Number of culture flasks/concentration:
- Method used to create aerobic conditions:
- Method used to create anaerobic conditions:
- Measuring equipment:
- Test performed in closed vessels due to significant volatility of test substance:
- Test performed in open system:
- Details of trap for CO2 and volatile organics if used:
- Other:

SAMPLING
- Sampling frequency:
- Sampling method:
- Sterility check if applicable:
- Sample storage before analysis:
- Other:

CONTROL AND BLANK SYSTEM
- Inoculum blank: yes
- Abiotic sterile control: yes
- Toxicity control: yes
- Other: adsorption control

STATISTICAL METHODS:

Reference substance

Reference substance:

aniline

Results and discussion

% Degradation

Parameter:

% degradation (DOC removal)

Value:

90 - 100

Sampling time:

18 d

Details on results:

Abiotic elimination (% DOC): 18 % after 18 days.

Kinetic of test substance (in %):
ca. 5 after 5 day(s)
ca. 10 after 6 day(s)
ca. 60 after 10 day(s)
> 90 after 16 day(s)
> 90 ... 100 after 18 day(s)

BOD5 / COD results

Results with reference substance:

Kinetic of control substance (in %):
ca. 10 after 3 day(s)
> 90 after 5 day(s)

Applicant's summary and conclusion

Interpretation of results:

readily biodegradable