Reaction mass of (E)-3-methylcyclotetradec-5-en-1-one and (Z)-3-methylcyclotetradec-5-en-1-one

Biodegradation in water: screening tests

Link to relevant study record(s)

Reference

Reference 1

Endpoint:

biodegradation in water: ready biodegradability

Type of information:

experimental study

Adequacy of study:

key study

Study period:

December 8 2003 to January 14 2004

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Remarks:

conducted under GLP conditions

Qualifier:

according to guideline

Guideline:

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

Version / remarks:

1992

Deviations:

no

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)

Specific details on test material used for the study:

Commercial Name: Karmalone
Chemical Nature: E/Z-3-methyl-5-cyclotetradecene-1-ene
Aspect: colourless to pale yellow liquid
Lot No.: TQT 0300497
Purity (GC) : 65.7 % (E isomer), 25.2 % (Z isomer)
Expiration date: November 28, 2004.

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, 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.

Inoculum concentration = 30mg/l (dry weight)

Duration of test (contact time):

34 d

Initial conc.:

100 mg/L

Based on:

test mat.

Parameter followed for biodegradation estimation:

O2 consumption

Details on study design:

Test substance samples (25 mg, corresponding to 100 mg/l in a 250-ml flask) are weighed in small aluminium boats and added directly to the test flasks of the SAPROMAT, whereas reference substance samples (sodium benzoate) are added as 1.0 ml of a 25 mg/ml solution in mineral medium.

All flasks are filled with 250 ml of mineral medium. Samples of test or reference substance, or both, are added. Then, a volume of suspended sludge corresponding to 7.5 mg dry weight (as determined from 3.6, generally 1 to 3 ml) is added. Except when the test substance has an acid or alkaline character, the pH of each flask is not measured but assumed to be the same as the mineral medium (see 3.5.), in order not to remove any floating undissolved test substance from the test medium by dipping a glass electrode in it. Neutral test substances, even sodium benzoate, were shown not to affect the pH of the medium by more than 0.1 pH unit. About 2 g of soda lime is placed in an attachment of the stopper, the flasks are closed and placed in the water bath of the SAPROMAT. After temperature and pressure equilibration, the oxygen-meters of the instrument are set to zero (time zero of the experiment).

Everyday the oxygen consumption of each flask is recorded and correct temperature and stirring are checked.
At the end of the test period (normally 28 days), the pH of each flask is measured again.

Toxicity of the test substance:
As suggested in the OECD 301F method, the toxicity of the test substance for the inoculum is checked. Therefore, a pair of flasks of the volumetric respirometer are filled with mineral medium + test substance (100mg/l) + reference substance (100mg/l)+ inoculum and their respirations are recorded as for the other flasks. If they are lower than those of the flasks containing mineral medium + reference substance (100mg/l) + inoculum, the test substance can be assumed to be inhibitory to the inoculum used.

Reference substance:

benzoic acid, sodium salt

Test performance:

Everyday the oxygen consumption of each flask is recorded and correct temperature and stirring are checked.
At the end of the test period (normally 28 days), the pH of each flask is measured again.
The respirometers used during this study are SAPROMAT D 12, made by J. M. VOITH GmbH, Heidenheim, Germany (Serial Nos. : SAPROMAT 1 : 9316, controller 1 : 1921, SAPROMAT 2 : 9511, controller 2 : 2067).

Key result

Parameter:

% degradation (O2 consumption)

Value:

70

Sampling time:

28 d

Parameter:

% degradation (O2 consumption)

Value:

73

Sampling time:

34 d

Details on results:

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

KARMALONE undergoes 70% biodegradation after 28 days (73% after 34 days) in the test conditions. The 10-day window criterion is not fulfilled (10% biodegradation on day 5 and 55% on day 15). The 10-day time window criterion was developed on the assumption that a test substance is degraded according to a “standard” growth curve in ready biodegradability tests. The OECD Guidelines for Testing of Chemicals, Section 3. Part 1: Principles and strategies related to the testing of degradation of organic chemicals (adopted 23 March 2006), states that if a substance consists of “constituents with different chain-lengths, degree and/or site of branching or stereo-isomers, even in their most purified commercial forms” and “it is anticipated that a sequential biodegradation of the individual structures is taking place, then the 10-day window should not be applied to interpret the results of the test.” The 10-day time-window should therefore not be applied as a pass / fail criterion for KARMALONE, which is a mixture of E- and Z-3-methyl-5-cyclotetradecen-1-one.

Results with reference substance:

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

Validity criteria fulfilled:

yes

Interpretation of results:

readily biodegradable

Conclusions:

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

KARMALONE undergoes 70% biodegradation after 28 days (73% after 34 days) in the test conditions. The 10-day window criterion is not fulfilled (10% biodegradation on day 5 and 55% on day 15). The 10-day time window criterion was developed on the assumption that a test substance is degraded according to a “standard” growth curve in ready biodegradability tests. The OECD Guidelines for Testing of Chemicals, Section 3. Part 1: Principles and strategies related to the testing of degradation of organic chemicals (adopted 23 March 2006), states that if a substance consists of “constituents with different chain-lengths, degree and/or site of branching or stereo-isomers, even in their most purified commercial forms” and “it is anticipated that a sequential biodegradation of the individual structures is taking place, then the 10-day window should not be applied to interpret the results of the test.” The 10-day time-window should therefore not be applied as a pass / fail criterion for KARMALONE, which is a mixture of E- and Z-3-methyl-5-cyclotetradecen-1-one.

Thus, KARMALONE should be regarded as readily biodegradable according to this test based on the biodegradation percentage of 70% at day 28.

Executive summary:

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

 

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

KARMALONE undergoes 70% biodegradation after 28 days (73% after 34 days) in the test conditions. The 10-day window criterion is not fulfilled (10% biodegradation on day 5 and 55% on day 15).The 10-day time window criterion was developed on the assumption that a test substance is degraded according to a “standard” growth curve in ready biodegradability tests. The OECD Guidelines for Testing of Chemicals, Section 3. Part 1: Principles and strategies related to the testing of degradation of organic chemicals (adopted 23 March 2006), states that if a substance consists of “constituents with different chain-lengths, degree and/or site of branching or stereo-isomers, even in their most purified commercial forms” and “it is anticipated that a sequential biodegradation of the individual structures is taking place, then the 10-day window should not be applied to interpret the results of the test.” The 10-day time-window should therefore not be applied as a pass / fail criterion for KARMALONE, which is a mixture of E- and Z-3-methyl-5-cyclotetradecen-1-one.

 

Thus, KARMALONE should be regarded as readily biodegradable according to this test based on the biodegradation percentage of 70 at day 28.

Reference 2

Endpoint:

biodegradation in water: inherent biodegradability

Type of information:

experimental study

Adequacy of study:

supporting study

Study period:

December 8 2003 to January 14 2004

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Remarks:

conducted under GLP conditions

Qualifier:

according to guideline

Guideline:

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

Version / remarks:

1981

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Specific details on test material used for the study:

Commercial Name: Karmalone
Chemical Nature: E/Z-3-methyl-5-cyclotetradecene-1-ene
Aspect: colourless to pale yellow liquid
Lot No.: TQT 0300497
Purity (GC) : 65.7 % (E isomer), 25.2 % (Z isomer)
Expiration date: November 28, 2004

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, 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.

Inoculum concentration = 100mg/L (dry weight).

Duration of test (contact time):

34 d

Initial conc.:

30 mg/L

Based on:

test mat.

Parameter followed for biodegradation estimation:

O2 consumption

Details on study design:

Test substance samples (7.5 mg, corresponding to 30 mg/l in a 250-ml flask) are weighed in small aluminium boats and added directly to the test flasks of the SAPROMAT, whereas reference substance samples (sodium benzoate) are added as 1.0 ml of a 25 mg/ml solution in mineral medium.

All flasks are filled with 250 ml of mineral medium. Samples of test or reference substance are added. Then, a volume of suspended sludge corresponding to 25 mg dry weight (as determined from 3.6, generally 1 to 3 ml) is added. Except when the test substance has an acid or alkaline character, the pH of each flask is not measured but assumed to be the same as the mineral medium (see 3.5.), in order not to remove any floating undissolved test substance from the test medium by dipping a glass electrode in it. Neutral test substances, even sodium benzoate, were shown not to affect the pH of the medium by more than 0.1 pH unit. About 2 g of soda lime is placed in an attachment of the stopper, the flasks are closed and placed in the water bath of the SAPROMAT. After temperature and pressure equilibration, the oxygen-meters of the instrument are set to zero (time zero of the experiment).

Reference substance:

benzoic acid, sodium salt

Remarks:

The activity of the inoculum was assessed in a simultaneous ready biodegradability test (OECD 301F). Test conditions were the same as the main test except that the reference concentration was 100mg/L & the inoculum concentration was 30mg/L, dry matter.

Test performance:

Everyday the oxygen consumption of each flask is recorded and correct temperature and stirring are checked.
At the end of the test period (normally 28 days), the pH of each flask is measured again.

Key result

Parameter:

% degradation (O2 consumption)

Value:

75

Sampling time:

28 d

Results with reference substance:

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

Validity criteria fulfilled:

yes

Interpretation of results:

inherently biodegradable

Conclusions:

KARMALONE undergoes 75% biodegradation after 28 days in the test conditions.

As the "pass" level for inherent biodegradability is 70%, KARMALONE should be regarded as inherently biodegradable according to this test.

Executive summary:

The Inherent Biodegradability of KARMALONE was determined by the Manometric Respirometry Test according to the OECD Guidelines for Testing of Chemicals, Method No. 302C.

 

KARMALONE undergoes 75% biodegradation after 28 days in the test conditions.

 

As the "pass" level for inherent biodegradability is 70%, KARMALONE should be regarded as inherently biodegradable according to this test.

Description of key information

The biodegradability of the registered substance, “Reaction mass of (E)-3-methylcyclotetradec-5-en-1-one and (Z)-3-methylcyclotetradec-5-en-1-one”, has been investigated in two standard screening methods; the OECD 301F Manometric Respirometry Test for screening ready biodegradability (key study) and the OECD 302C Inherent Biodegradability, Modified MITI II test (supporting study). A high level of biodegradation was observed in both tests (73% after 34 days in the 301F; 75% after 28 days in the 302C) indicating that the substance is ultimately biodegradable and not persistent in the environment.

In the OECD 301F study, the registered substance achieved the pass level of ready biodegradability of 60% ThOD within a 28-d period (70% after 28 days). The 10-day window criterion was not fulfilled (10% biodegradation on day 5 and 55% on day 15). However, the 10-day time window criterion was developed on the assumption that a test substance is degraded according to a standard growth curve in ready biodegradability tests. The OECD Guidelines for Testing of Chemicals, Section 3. Part 1: Principles and strategies related to the testing of degradation of organic chemicals (adopted 23 March 2006), states that if a substance consists of “constituents with different chain-lengths, degree and/or site of branching or stereo-isomers, even in their most purified commercial forms” and “it is anticipated that a sequential biodegradation of the individual structures is taking place, then the 10-day window should not be applied to interpret the results of the test.” The 10-day time-window should therefore not be applied as a pass / fail criterion for the registered substance, which is a mixture of E- and Z-3-methyl-5-cyclotetradecene-1-one. Thus, the registered substance is regarded as readily biodegradable according to the test based on the biodegradation percentage of 70% at day 28.

Key value for chemical safety assessment

Biodegradation in water:

readily biodegradable

Type of water:

freshwater