(E)-3,5-dimethylhex-3-en-2-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:

guideline study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2015

Report date:

2015

Materials and methods

Test guideline

Test guideline 1

Qualifier:

according to guideline

Guideline:

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

Test guideline 2

Qualifier:

according to guideline

Guideline:

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

Test guideline 3

Qualifier:

according to guideline

Guideline:

EPA OPPTS 835.3110 (Ready Biodegradability)

GLP compliance:

yes (incl. QA statement)

Test material

Test material information

Constituent 1

Reference substance name:

(E)-3,5-dimethylhex-3-en-2-one

EC Number:

606-014-9

Cas Number:

18402-86-3

Molecular formula:

C8H14O

IUPAC Name:

(E)-3,5-dimethylhex-3-en-2-one

impurity 1

Reference substance name:

(E)-3,4-dimethylhex-4-en-2-one

Cas Number:

20685-50-1

Molecular formula:

C8H14O

IUPAC Name:

(E)-3,4-dimethylhex-4-en-2-one

impurity 2

Reference substance name:

3,5-dimethylhex-4-en-2-one

Cas Number:

36616-77-0

Molecular formula:

C8H14O

IUPAC Name:

3,5-dimethylhex-4-en-2-one

Test material form:

liquid

Specific details on test material used for the study:

Commercial Name: Secodemone
Givaudan Code No.: 0029283
Chemical Nature: (E)-3,5-dimethylhex-3-en-2-one
Empirical Formula: C8H14O
Molecular weight: 126.20 g/mol
CAS No.: 18402-86-3
Aspect: colourless to pale yellow liquid
Lot No.: SC00010091
Expiration Date: October 31, 2016

Study design

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 (Bois-de-Bay, Satigny, Switzerland) 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):

48 d

Initial test substance concentration

Initial conc.:

30 mg/L

Based on:

test mat.

Parameter followed for biodegradation estimation

Parameter followed for biodegradation estimation:

O2 consumption

Reference substance

Reference substance:

benzoic acid, sodium salt

Remarks:

(Fluka, Buchs, Switzerland, Art. No. 71300), purity : min. 99.0%.

Results and discussion

Test performance:

Degradation of sodium benzoate exceeded 40% after 7 days and 65% after 14 days: the activity of the inoculum was thus verified (validity criterion).

The repeatability validity criterion (not more than 20% difference between replicates) is fulfilled. Therefore, the test is considered valid.

% Degradation

% Degradation 1

Parameter:

% degradation (O2 consumption)

Value:

86

Sampling time:

28 d

% Degradation 2

Parameter:

% degradation (O2 consumption)

Value:

77

Sampling time:

14 d

% Degradation 3

Parameter:

% degradation (O2 consumption)

Value:

15

Sampling time:

4 d

Applicant's summary and conclusion

Validity criteria fulfilled:

yes

Interpretation of results:

readily biodegradable

Conclusions:

Secodemone undergoes 86% biodegradation after 28 days in the test conditions. The 10-day window criterion is also fulfilled (15% biodegradation on day 4 and 77% on day 14).

Secodemone did not inhibit the intrinsic respiration of the inoculum at the test concentration and was therefore considered to be non-toxic to the inoculum at the test concentration.

Thus, Secodemone should be regarded as readily biodegradable according to this test.