4-(1-ethoxyvinyl)-3,3,5,5-tetramethylcyclohexanone

Biodegradation in water: screening tests

Link to relevant study record(s)

Reference

Reference 1

Endpoint:

biodegradation in water: inherent biodegradability

Type of information:

experimental study

Adequacy of study:

key study

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

OECD Guideline 302 C (Inherent Biodegradability: Modified MITI Test (II))

GLP compliance:

yes (incl. QA statement)

Specific details on test material used for the study:

Commercial name: Kephalis
Chemical Nature: 4-(1-ethoxyvinyl)-3,3,5,5-tetramethylcyclohexanone (main component)
Empirical Formula: C14H24O2
Molecular weight: 224.4 g/mol
CAS No.: 36306-87-3
Aspect: pale yellow liquid
Lot No.: 9000318620
Purity: 87.8% (GC, sum of two peaks)

Oxygen conditions:

aerobic

Inoculum or test system:

activated sludge, domestic, non-adapted

Details on inoculum:

Fresh activated sludge from a biological waste water treatment plant treating predominantly domestic sewage (City of Geneva) 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):

28 d

Initial conc.:

30 mg/L

Based on:

test mat.

Parameter followed for biodegradation estimation:

O2 consumption

Reference substance:

benzoic acid, sodium salt

Remarks:

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

Parameter:

% degradation (O2 consumption)

Value:

4

Sampling time:

28 d

Validity criteria fulfilled:

yes

Interpretation of results:

not inherently biodegradable

Conclusions:

The Inherent Biodegradability of Kephalis was determined by the Manometric Respirometry Test according to the OECD Guidelines for Testing of Chemicals, Method No. 302C.
Kephalis undergoes only 4% biodegradation after 28 days in the test conditions, which is not significant.
Thus, Kephalis shoud be regarded as not inherently biodegradable according to this test.

Reference 2

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

Qualifier:

according to guideline

Guideline:

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

GLP compliance:

yes (incl. QA statement)

Specific details on test material used for the study:

Commercial name: Kephalis
Chemical Nature: 4-(1-ethoxyvinyl)-3,3,5,5-tetramethylcyclohexanone and 1-ethoxy-4-(1-ethoxyvinyl)-3,3,5,5-tetramethylcyclohexanone
Empirical Formula: C14H24O2
Molecular weight: 224.4 g/mol
CAS No.: 36306-87-3
Appearance: pale yellow liquid
Purity: 92.5% (GC, sum of two peaks)

Note:
Please note that although the substance is stated as a mixture of 4-(1-ethoxyvinyl)-3,3,5,5-tetramethylcyclohexanone and 1-ethoxy-4-(1-ethoxyvinyl)-3,3,5,5-tetramethylcyclohex-1-ene in the report, recent analytical data has determined the substance to be a mono-constituent substance (4-(1-ethoxyvinyl)-3,3,5,5-tetramethylcyclohexanone). As the chemical manufacturing process has not changed since the report was written, the recent analytical information is relevant to the batch which was tested (1-ethoxy-4-(1-ethoxyvinyl)-3,3,5,5-tetramethylcyclohex-1-ene is not present in the substance).

Oxygen conditions:

aerobic

Inoculum or test system:

activated sludge, domestic, non-adapted

Details on inoculum:

Fresh activated sludge from a biological waste water treatment plant treating predominantly domestic sewage (City of Geneva) 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):

28 d

Initial conc.:

100 mg/L

Based on:

test mat.

Parameter followed for biodegradation estimation:

O2 consumption

Reference substance:

aniline

Remarks:

(Merck, Darmstadt, Germany, Art. No. 1261) Purity: min. 99.5%

Parameter:

% degradation (O2 consumption)

Value:

0

Sampling time:

28 d

Details on results:

The curves obtained with Aniline alone and with Kephalis + aniline show no significant toxic effect of Kephalis on the micro-organisms at the test concentration.

Validity criteria fulfilled:

yes

Interpretation of results:

not readily biodegradable

Conclusions:

The Readily Biodegradability of Kephalis has been determined by the Manometric Respirometry Test according to the OECD Guidelines for Testing of Chemicals, Method No. 301 F. Kephalis ungergoes no biodegradation after 28 days in the test conditions. Thus, Kephalis should be regarded as not readily biodegradable according to this test.
At the test concentration (100 mg/l), Kephalis shows no inhibitory effect on the micro-organisms.

Description of key information

The ready biodegradability of Kephalis was determined by the Manometric Respiratory Test according to OECD Guidelines No 301F. Under the conditions of the study the test substance underwent 0 % biodegradation after 28 days. Thus, the test substance should be regarded as not readily biodegradable according to this test.

The inherent biodegradability of Kephalis was determined by the Manometric Respirometry Test according to the OECD Guidelines for Testing of Chemicals, Method No. 302C. Kephalis undergoes only 4% biodegradation after 28 days in the test conditions, which is not significant. Thus, Kephalis should be regarded as not inherently biodegradable according to this test.

Based on the above two tests, the conclusion for the chemical safety assessment is that no biodegradation was observed.

Key value for chemical safety assessment

Biodegradation in water:

under test conditions no biodegradation observed

Additional information

An inhibition control was included in the ready biodegradability test. At the concentration used in the test (100 mg/l), Kephalis was not inhibitory to the micro-organisms. This concentration can be considered as a NOEC for the toxicity to STP microorganisms.