α,2,2,6-tetramethylcyclohexene-1-butyraldehyde

Biodegradation in water: screening tests

Administrative data

Endpoint:

biodegradation in water: ready biodegradability

Type of information:

experimental study

Adequacy of study:

key study

Study period:

January 22, 2003 to March 4, 2003

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2003

Report date:

2003

Materials and methods

Test guideline

Test guideline 1

Qualifier:

according to guideline

Guideline:

OECD Guideline 301 F (Ready Biodegradability: Manometric Respirometry Test)

Deviations:

no

Test guideline 2

Qualifier:

according to guideline

Guideline:

EU Method C.4-D (Determination of the "Ready" Biodegradability - Manometric Respirometry Test)

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Test material

Test material information

Constituent 1

Reference substance name:

α,2,6,6-tetramethyl-2-cyclohexene-1-butyraldehyde

EC Number:

277-458-5

EC Name:

α,2,6,6-tetramethyl-2-cyclohexene-1-butyraldehyde

Cas Number:

73398-85-3

Molecular formula:

C14H24O

IUPAC Name:

2-methyl-4-(2,6,6-trimethylcyclohex-2-en-1-yl)butanal

Constituent 2

Reference substance name:

α,2,6,6-tetramethylcyclohexene-1-butyraldehyde

EC Number:

282-993-2

EC Name:

α,2,6,6-tetramethylcyclohexene-1-butyraldehyde

Cas Number:

84518-22-9

Molecular formula:

C14H24O

IUPAC Name:

2-methyl-4-(2,6,6-trimethylcyclohex-1-en-1-yl)butanal

Specific details on test material used for the study:

Test material name (as stated in the report): Cetonal
Batch No.: 9000439021
Expiry date: December 28, 2004

Study design

Oxygen conditions:

aerobic

Inoculum or test system:

activated sludge, domestic (adaptation not specified)

Details on inoculum:

Fresh activated sludge from a biological waste water treatment plant treating predominantly domestic sewage (City of Geneva, Peney-Dessous) was used. The sludge is collected in the morning, washed three times in the mineral medium (by centrifuging at 1000 g for 10 minutes, discarding the supernatant and resuspending in mineral medium) and kept aerobic until being used on the same day.

Duration of test (contact time):

35 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

Reference substance

Reference substance:

other: Sodium benzoate

Results and discussion

% Degradation

Key result

Parameter:

% degradation (O2 consumption)

Value:

70

Sampling time:

28 d

Details on results:

The 10-day window criterion is fulfilled. Biodegradation starts on day 5 and reaches 60% at the end of the 10-day window (days 5 to 15).

Any other information on results incl. tables

The curves obtained with the reference substance alone and with CETONAL + reference substance show no toxic effect of CETONAL to the micro-organisms at the test concentration (100 mg/l).

Applicant's summary and conclusion

Validity criteria fulfilled:

yes

Interpretation of results:

readily biodegradable

Conclusions:

CETONAL undergoes 70% biodegradation after 28 days (72% after 35 days) in the test conditions. Biodegradation starts on day 5 and reaches 60% at the end of the 10-day window (days 5 to 15). Hence, the 10-day window criterion is fulfilled.

Executive summary:

The Ready Biodegradability of CETONAL was determined by the Manometric Respirometry Test according to the OECD Guidelines for Testing of Chemicals, Method No. 301 F.

CETONAL undergoes 70% biodegradation after 28 days (72% after 35 days) in the test conditions. Biodegradation starts on day 5 and reaches 60% at the end of the 10-day window (days 5 to 15). Hence, the 10-day window criterion is fulfilled.

 The curves obtained with the reference substance alone and with CETONAL + reference substance show no toxic effect of CETONAL to the micro-organisms at the test concentration (100 mg/l).

 Thus, CETONAL should be regarded as readily biodegradableaccording to this test.