Registration Dossier

Data platform availability banner - registered substances factsheets

Please be aware that this old REACH registration data factsheet is no longer maintained; it remains frozen as of 19th May 2023.

The new ECHA CHEM database has been released by ECHA, and it now contains all REACH registration data. There are more details on the transition of ECHA's published data to ECHA CHEM here.

Diss Factsheets

Environmental fate & pathways

Biodegradation in water: screening tests

Currently viewing:

Administrative data

Link to relevant study record(s)

Referenceopen allclose all

Endpoint:
biodegradation in water: ready biodegradability
Type of information:
experimental study
Adequacy of study:
weight of evidence
Study period:
2015-06-25 to 2015-07-23
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)
Version / remarks:
1992
Deviations:
no
Qualifier:
according to guideline
Guideline:
EU Method C.4-D (Determination of the "Ready" Biodegradability - Manometric Respirometry Test)
Version / remarks:
2008
Deviations:
no
GLP compliance:
yes (incl. QA statement)
Specific details on test material used for the study:
- chemical name: 1-Propanaminium, 2-hydroxy-N-(2- hydroxypropyl)-N,N-dimethyl-, esters with C 16/18 and C18-unsat. fatty acids, Me sulfates (salts)
Oxygen conditions:
aerobic
Inoculum or test system:
activated sludge, domestic, non-adapted
Details on inoculum:
- Source of inoculum/activated sludge (e.g. location, sampling depth, contamination history, procedure): sewage treatment plant Ruhrverband Kläranlage, Sunthelle 6, 57392 Schmallenberg, Germany; sample from June 24th, 2015 (one day before test start)

Since the sludge had not been taken from a high rate treatment plant and was not thought to contain inhibitors, the samples were not washed with mineral medium after the arrival at the laboratory, they were kept aerobic until use. The sludge was left for settlement for ca. an hour. Subsequently the supernatant was discarded and the concentration of suspended solids was measured in the remaining sludge. The concentration was adjusted to 3.6 g/L and verified by dry mass measurement. The sludge was kept aerated overnight. Before test start, the concentration was adjusted to 4.5 g/L and verified by dry mass measurement. The
concentration used in the test was 29.5 mg dry mass/litre (7.38 mg dry mass/250 mL).
Duration of test (contact time):
28 d
Initial conc.:
460 mg/L
Based on:
act. ingr.
Initial conc.:
60 mg/L
Based on:
ThOD/L
Parameter followed for biodegradation estimation:
O2 consumption
Details on study design:
TEST CONDITIONS
- Composition of medium: as stipulated in OECD guideline 301
- Additional substrate: no
- Test temperature: 22±1°C
- pH: 7.4,no adjustment required
- Suspended solids concentration: 3.6 mg/L
- Continuous darkness: yes

TEST SYSTEM
- Culturing apparatus: 500 mL glass vessels, medium volume of 250 mL
- Number of culture flasks/concentration: 2
- Method used to create aerobic conditions: aeration

SAMPLING
continuous measurement and recording of oxygen demand

CONTROL AND BLANK SYSTEM
- Test suspension: 2 vessels containing test item (460 mg/L) and inoculum
- Inoculum blank: 2 vessels containing only inoculum
- Procedural control: 2 vessels containing reference item (100 mg/L) and inoculum
- Toxicity control: 2 vessels containing test item (460 mg/L), reference item (100 mg/L) and inoculum
Reference substance:
benzoic acid, sodium salt
Remarks:
100 mg/L
Parameter:
% degradation (O2 consumption)
Value:
65.5
St. dev.:
2.4
Sampling time:
14 d
Parameter:
% degradation (O2 consumption)
Value:
79
St. dev.:
4.8
Sampling time:
28 d
Details on results:
The biodegradation of the test item after 28 days of incubation was found to be 79 % (SD = 4.8 %) in assays with 460 mg/L. The biodegradation within the 10-daywindow was 65 %. The 10-day-window started at day 2.
The biodegradation of the item mixture in the toxicity control was found to be 75 % after 14 days of incubation. Thus, the demanded threshold value of 25 % is exceeded and the test item can be identified as non-toxic in a ready biodegradability test.
According to the OECD guideline 301F the test item can be considered as being readily biodegradable under the chosen test conditions.
Results with reference substance:
The reference item sodium benzoate was degraded to 85 % within the first 14 days.

The Manometric Respirometry Test fulfills the validity criteria of the guideline:

- With 7 % the difference of extremes of replicate values of the removal of the test item at the end of the test was less than 20 %.

- The percentage degradation of the reference item has exceeded the pass level of 60 % by day 14.

- The oxygen uptake of the inoculum blank is < 60 mg/L in 28 days and the pH value was inside the range of 6.0 - 8.5.

Validity criteria fulfilled:
yes
Interpretation of results:
readily biodegradable
Conclusions:
In this test, MDIPA-Esterquat C16-18 and C18 unsatd. was readily biodegradable and fulfilled the 10-day window criterion.
Executive summary:

The biodegradation of MDIPA-Esterquat C16-18 and C18 unsatd. was investigated over a 28-day period in a Manometric Respirometry Test according to EC method C.4-D (2008) and OECD guideline 301 F (1992).

The test solutions were stirred in closed flasks at 22°C ± 1°C for 28 days. The rate of degradation was monitored by measuring the quantity of oxygen required to maintain a constant gas volume in the respirometer flasks over a 28-d period. The amount of oxygen taken up by the microbial population during biodegradation of the test item at a concentration of 460 mg/L (ThOD = 60 mg/L), corrected for uptake by the blank inoculum run in parallel, was expressed as a percentage of the ThOD (theoretical oxygen demand). In order to check the procedure, sodium benzoate was used as a degradable reference item at a concentration of 100 mg/L, along with a toxicity control at 460 mg/L test item and 100 mg/L sodium benzoate.

The biodegradation of the test item was found to be at mean 79% with a standard deviation of 6.7 % for a concentration of 460 mg test item per liter after 28 days. Biodegradation within the 10-day-window was found to be 65%. The 10-day-window started at day 2.

The degradation of the reference substance sodium benzoate had reached 85 % within the first 14 days. The difference of extremes of replicate values of the removal of the test item at the end of the test is less than 20%.Therefore, the test can be considered as valid.

The biodegradation of the item mixture in the toxicity control was found to be 75% after 14 days of incubation. Thus, the demanded threshold value of 25% is exceeded and the test item can be identified as non-toxic in a ready biodegradability test.

According to the OECD guideline 301F, MDIPA-Esterquat C16-18 and C18 unsatd. can be considered as being readily biodegradable under the chosen test conditions.

Endpoint:
biodegradation in water: ready biodegradability
Type of information:
experimental study
Adequacy of study:
weight of evidence
Study period:
2011-02-10 to 2011-03-12
Reliability:
1 (reliable without restriction)
Rationale for reliability incl. deficiencies:
guideline study
Qualifier:
according to guideline
Guideline:
OECD Guideline 301 B (Ready Biodegradability: CO2 Evolution Test)
Version / remarks:
(17th July 1992)
Deviations:
no
Qualifier:
according to guideline
Guideline:
EU Method C.4-C (Determination of the "Ready" Biodegradability - Carbon Dioxide Evolution Test)
Version / remarks:
(July 1992)
Deviations:
no
GLP compliance:
yes (incl. QA statement)
Oxygen conditions:
aerobic
Inoculum or test system:
activated sludge, domestic, non-adapted
Details on inoculum:
- Source of inoculum/activated sludge (e.g. location, sampling depth, contamination history, procedure):
sample fromFebruary 10th, 2011 from sewage treatment plant in 57392 Schmallenberg, Germany, which is mainly fed with municipal wastewater;
samples were washed once with mineral medium after the arrival at the laboratory and kept aerobic until use
- Concentration of sludge: concentration used in the test: 29 mg dry mass/L (87 mg dry mass/3 L)
Duration of test (contact time):
28 d
Initial conc.:
20 mg/L
Based on:
DOC
Parameter followed for biodegradation estimation:
CO2 evolution
Details on study design:
TEST CONDITIONS
- Composition of medium: as stipulated in OECD guideline 301
- Additional substrate: no
- Test temperature: 22°C
- pH: 7.4
- Suspended solids concentration: 29 mg/L
- Continuous darkness: yes

TEST SYSTEM
- Culturing apparatus: 5 L flasks
- Number of culture flasks/concentration: 2
- Method used to create aerobic conditions: aeration
- Measuring equipment: absorption bottles, each containing 200 mL of 0.05 M sodium hydroxide solution
- Details of trap for CO2 and volatile organics if used: see above

SAMPLING
The process of biodegradation was followed by CO2 trapped in sodium hydroxide and measured as inorganic carbon. On the days of CO2 measurement, the sodium hydroxide absorbers were disconnected and aliquots of the solutions were measured regarding the TIC concentration. New absorbers (each containing 200 mL fresh 0.05 M sodium hydroxide) were connected to the test vessel.
On the 28th day 1 mL of concentrated hydrochloric acid was added to each test vessel. Subsequently, they were aerated overnight to drive off the carbon dioxide present in the test suspensions. On day 29 the last analysis of evolved carbon dioxide was done. Additionally, the biodegradation was measured by determining the DOC in samples of suspension taken at start and 28 d after addition of the test item. The samples at day 28 were taken before the concentrated hydrochloric acid was added.

CONTROL AND BLANK SYSTEM
- Inoculum blank: 2 vessels containing only inoculum
- Abiotic sterile control: 1 vessel containing test item (20 mg/L) and a sterilising agent
- Toxicity control: 1 vessel containing test item (20 mg/L), reference item (20 mg/L) and inoculum
- procedural control: reference item (20 mg/L) and inoculum
Reference substance:
benzoic acid, sodium salt
Remarks:
20 mg DOC / L
Parameter:
% degradation (inorg. C analysis)
Value:
34
St. dev.:
7
Sampling time:
14 d
Parameter:
% degradation (inorg. C analysis)
Value:
60
St. dev.:
10
Sampling time:
28 d
Parameter:
% degradation (DOC removal)
Value:
80
St. dev.:
23
Sampling time:
28 d
Parameter:
% degradation (inorg. C analysis)
Value:
50
St. dev.:
4.5
Sampling time:
17 d
Remarks on result:
other: % degr. at end of 10-day window
Details on results:
The biodegradation of the test substance was 60 % at a concentration of 20 mg/L after 28 days. The 10-day window started at day seven. The biodegradation after the 10-day-window was 50%. No lag phase /adaptation phase was noticeable.
In the toxicity controls the biodegradation was found to be 61% , after 14 days of incubation. Thus, the demanded threshold value of 25 % is exceeded and the test item can be identified as non toxic in aready biodegradability test.
Results with reference substance:
The reference item sodium benzoate was degraded to 100 % within the first 14 days.
The toxicity control test with 20 mg DOC/L resp. 28.2 mg A.I./L test substance and 20 mg/L reference item resulted in 61% degradation after 14 days and 91% degradation after 28 days.

Validity

The test is considered valid, as

with 14 %, the difference of extremes of replicate values of the removal of the test item at the end of the test fall below the threshold value of 20 %,

the percentage degradation of the reference item has exceeded the pass level of 60 % by day 14,

with 65.3 mg CO2per liter (17.8 mg C/L), the total CO2evolution in the inoculum blank at the end of the test is below the demanded value of 70 mg CO2per liter

with 3.7 %, the mean IC content in the mineral medium of the suspensions containing test item at the beginning of the test fall below the demanded threshold value of 5 % of the TC.

Validity criteria fulfilled:
yes
Interpretation of results:
readily biodegradable, but failing 10-day window
Conclusions:
In this test, MDIPA-Esterquat C16-18 and C18 unsatd. was readily biodegradable, but did not fulfil the 10-day window criterion.
Executive summary:

The biodegradation of MDIPA-Esterquat C16-18 and C18 unsatd. was investigated over a 28-day period in a CO2 Evolution Test according to EC method C.4-C (92/69/EEC) and OECD guideline 301 B. The test medium was inoculated with microorganisms from a digester of a sewage treatment plant mainly fed with municipal wastewater.

The test substance was added from a stock solution made from an aqueous dispersion (5.28% a.i. w/w) provided by the sponsor. The test solutions were aerated by the passage of CO2 free air at a controlled rate in closed flasks at 22 °C for 28 days. The rate of degradation was monitored by measuring the carbon dioxide produced over the 28-d period. The amount of carbon dioxide produced by the microbial population during biodegradation of the test item at a concentration of 20 mg/L, corrected for that derived from the blank inoculum run in parallel, was expressed as a percentage of the nominal DOC loading initially present. In order to check the procedure, sodium benzoate was used as a degradable reference item at a concentration of 20 mg/L, along with a toxicity control at 20 mg/L MDIPA-Esterquat C16-18 and C18 unsatd., and 20 mg/L sodium benzoate.

The degradation of MDIPA-Esterquat C16-18 and C18 unsatd. in the static test was found to be 60 % after 28 days. Biodegradation within the 10-day-window was found to be 40 % on the basis of the values obtained by measurement of the trap solutions in the course of the study and calculated to be 50 % assuming that the saturation of CO2 in the media found after acid dissolving at test end is stable after a few days of incubation.

With 40 % after 28 days, a significant abiotic degradation occurred.

The degradation of the reference substance sodium benzoate had reached 100 % within the first 14 days (103 % considering the medium fixed amount). The difference of extremes of replicate values of the removal of the test item at the end of the test is 14 %. Therefore, the test can be considered as valid.

No inhibitory effects of the test item were observed (more than 25 % degradation occurred within 14 days) in the toxicity control.

Although the 10-day window criterion is not fulfilled, the test substance can be regarded as readily biodegradable as it is a UVCB substance representing a complex multi-constituent substance with structurally similar constituents:

1.according to the REACH Guidance on information requirements and chemical safety assessment, Chapter R.7b: Endpoint specific guidance “These pass levels have to be reached in a 10-day window within the 28-day period of the test. The 10-day window does not apply to TG 301 C or if the test substance represents a mixture of homologous compounds e.g. technical surfactants."

2. according to CLP 7th ATP, 4.1.2.9.5.: "These levels of biodegradation must be achieved within 10 days of the start of degradation which point is taken as the time when 10 % of the substance has been degraded, unless the substance is identified as an UVCB or as a complex, multi-constituent substance with structurally similar constituents. In this case, and where there is sufficient justification, the 10-day window condition may be waived and the pass level applied at 28 days."

Endpoint:
biodegradation in water: ready biodegradability
Type of information:
experimental study
Adequacy of study:
weight of evidence
Study period:
2015-06-24 to 2015-07-24
Reliability:
1 (reliable without restriction)
Rationale for reliability incl. deficiencies:
guideline study
Qualifier:
according to guideline
Guideline:
OECD Guideline 301 B (Ready Biodegradability: CO2 Evolution Test)
Version / remarks:
1992
Deviations:
no
Qualifier:
according to guideline
Guideline:
EU Method C.4-C (Determination of the "Ready" Biodegradability - Carbon Dioxide Evolution Test)
Version / remarks:
2008
Deviations:
no
GLP compliance:
yes (incl. QA statement)
Specific details on test material used for the study:
- chemical name: 1-Propanaminium, 2-hydroxy-N-(2- hydroxypropyl)-N,N-dimethyl-, esters with C 16/18 and C18-unsat. fatty acids, Me sulfates (salts)
Oxygen conditions:
aerobic
Inoculum or test system:
activated sludge, domestic, non-adapted
Details on inoculum:
- Source of inoculum/activated sludge (e.g. location, sampling depth, contamination history, procedure): Ruhrverband Kläranlage, Sunthelle 6, 57392 Schmallenberg, Germany; sample from June 24th, 2015

The sludge was washed in mineral medium and centrifuged (at 1100 g for 10 minutes). The supernatant was discarded. The concentrated sludge was suspended in mineral medium to a concentration of 1 – 3 g suspended solids/L. The sludge was aerated with CO2-free air over night to purge the system of carbon dioxide. A sample was withdrawn just before use for the determination of the dry weight of the suspended solids. The concentration used in the test was 10 mg dry mass/litre (30 mg dry mass/3 L).
Duration of test (contact time):
28 d
Initial conc.:
17 mg/L
Based on:
other: TOC
Initial conc.:
24.3 mg/L
Based on:
act. ingr.
Parameter followed for biodegradation estimation:
CO2 evolution
Details on study design:
TEST CONDITIONS
- Composition of medium: as stipulated in OECD guideline 301
- Additional substrate: no
- Test temperature: 22±2°C
- pH: 7.4, no adjustment required
- Suspended solids concentration: 9.9 mg/L
- Continuous darkness: yes

TEST SYSTEM
- Culturing apparatus: 5 L flasks
- Number of culture flasks/concentration: 3
- Method used to create aerobic conditions: aeration
- Measuring equipment: absorption bottles, each containing 200 mL of 0.05 M sodium hydroxide solution

SAMPLING
The process of biodegradation was followed by CO2 trapped in sodium hydroxide and measured as inorganic carbon. On the days of CO2 measurement, the sodium hydroxide absorbers were disconnected and aliquots of the solutions were measured regarding the TIC concentration. New absorbers (each containing 200 mL fresh 0.05 M sodium hydroxide) were connected to the test vessel.
On the 28th day 1 mL of concentrated hydrochloric acid was added to each test vessel. Subsequently, they were aerated overnight to drive off the carbon dioxide present in the test suspensions. On day 29 the last analysis of evolved carbon dioxide was done.
Days of sampling for CO2 measurement were day 3, 5, 7, 11, 15, 21, and 29

CONTROL AND BLANK SYSTEM
- Inoculum blank: 2 vessels containing only inoculum
- Procedural control: 1 vessel containing reference item (20 mg DOC/L) and inoculum
- Test suspension: 3 vessels containing test item (17 mg TOC/L) and inoculum
- Toxicity control: 1 vessel containing test item (17 mg TOC/L), reference item (20 mg DOC/L) and inoculum
- Medium control: 1 vessel containing only mineral medium
Reference substance:
benzoic acid, sodium salt
Remarks:
20 mg DOC/L
Parameter:
% degradation (CO2 evolution)
Value:
24.7
St. dev.:
1.3
Sampling time:
11 d
Parameter:
% degradation (CO2 evolution)
Value:
68.6
St. dev.:
1.3
Sampling time:
28 d
Details on results:
The biodegradation of the test item was found to be 69 % after 28 days, considering the amount of IC measured after acid dissolving on day 28. The degradation within the 10-day-window was 36 % on the basis of the values obtained by measurement of the trap solutions in the course of the study. The 10-day window started at day five. No significant lag phase / adaptation phase was noticeable.
The biodegradation of the item mixture in the toxicity control was found to be 48 % after 11 days of incubation. Thus, the demanded threshold value of 25 % within 14 days is exceeded and the test item can be identified as non-toxic in a ready biodegradability test.

Due to a degradation achieving the threshold value of 60 % within the 28-day-test duration but not within a 10-day window, the test item can be identified as being readily biodegradable but failing the 10-day-window under the chosen test conditions
Results with reference substance:
The reference item sodium benzoate was degraded to 95 % within the first 11 days. Thus, the demanded threshold value of 60 % within 14 days is exceeded.

The CO2 Evolution Test fulfills the validity criteria of the guideline:

- With 5 % the difference of extremes of replicate values of the removal of the test item at the end of the test was less than 20 %.

- The percentage degradation of the reference item has exceeded the pass level of 60 % by day 14.

- With 19.8 mg CO2 per liter (7.8 mg C/L), the total CO2 evolution in the inoculum blank at the end of the test is below the demanded value of 70 mg CO2 per liter.

- With 1.1 %, the mean IC content in the mineral medium used for assay preparation fall below the demanded threshold value of 5 % of the TC (nominal) in the test assays.

Validity criteria fulfilled:
yes
Interpretation of results:
readily biodegradable, but failing 10-day window
Conclusions:
In this test, MDIPA-Esterquat C16-18 and C18 unsatd. was readily biodegradable, but did not fulfil the 10-day window criterion.
Executive summary:

The biodegradation of MDIPA-Esterquat C16-18 and C18 unsatd. was investigated over a 28-day period in a CO2 Evolution Test according to EC method C.4-C (2008) and OECD guideline 301 B (1992). The test medium was inoculated with microorganisms from a digester of a sewage treatment plant mainly fed with municipal wastewater.

The test solutions were aerated by the passage of CO2 free air at a controlled rate in closed flasks at 22±2°C for 28 days. The rate of degradation was monitored by measuring the carbon dioxide produced over the 28-d period. The amount of carbon dioxide produced by the microbial population during biodegradation of the test item at a concentration of 17 mg C/L, corrected for that derived from the blank inoculum run in parallel, was expressed as a percentage of the nominal TOC loading initially present. In order to check the procedure, sodium benzoate was used as a degradable reference item at a concentration of 20 mg DOC/L, along with a toxicity control at 17 mg TOC/L test item, and 20 mg DOC/L sodium benzoate.

The biodegradation of the test item was found to be 69% after 28 days. Degradation within the 10-day-window was found to be 36% on the basis of the values obtained by measurement of the trap solutions in the course of the study.

The degradation of the reference substance sodium benzoate had reached 95% within the first 14 days (actually within 11 days). The difference of extremes of replicate values of the removal of the test item at the end of the test is 5%. Therefore, the test can be considered as valid.

No inhibitory effects of the test item were observed (more than 25% degradation occurred within 14 days; 48% after 11 days of incubation) in the toxicity control.

MDIPA-Esterquat C16-18 and C18 unsatd. can be considered as being readily biodegradable but failing the 10-day-window under the test conditions of an OECD 301B test.

Although the 10-day window criterion is not fulfilled, the test substance can be regarded as readily biodegradable as it is a UVCB substance representing a complex multi-constituent substance with structurally similar constituents:

1.according to the REACH Guidance on information requirements and chemical safety assessment, Chapter R.7b: Endpoint specific guidance “These pass levels have to be reached in a 10-day window within the 28-day period of the test. The 10-day window does not apply to TG 301 C or if the test substance represents a mixture of homologous compounds e.g. technical surfactants."

2. according to CLP 7th ATP, 4.1.2.9.5.: "These levels of biodegradation must be achieved within 10 days of the start of degradation which point is taken as the time when 10 % of the substance has been degraded, unless the substance is identified as an UVCB or as a complex, multi-constituent substance with structurally similar constituents. In this case, and where there is sufficient justification, the 10-day window condition may be waived and the pass level applied at 28 days."

Description of key information

readily biodegradable (OECD guideline 301 B/EU method C.4-C and OECD guideline 301 F/EU method C.4-D; RL1; GLP)

Key value for chemical safety assessment

Biodegradation in water:
readily biodegradable
Type of water:
freshwater

Additional information

For the assessment of the biodegradability of MDIPA-Esterquat C16-18 and C18 unsatd. three studies are available, two studies according to OECD guideline 301 B, and one study according to OECD guideline 301 F.


 


The biodegradation of MDIPA-Esterquat C16-18 and C18 unsatd. was investigated over a 28-day period in a CO2 Evolution Test according to EC method C.4-C (92/69/EEC) and OECD guideline 301 B. The test medium was inoculated with microorganisms from a digester of a sewage treatment plant mainly fed with municipal wastewater.


The test substance was added from a stock solution made from an aqueous dispersion (5.28% a.i. w/w) provided by the sponsor.


The test solutions were aerated by the passage of CO2 free air at a controlled rate in closed flasks at 22 °C for 28 days. The rate of degradation was monitored by measuring the carbon dioxide produced over the 28-d period. The amount of carbon dioxide produced by the microbial population during biodegradation of the test item at a concentration of 20 mg/L, corrected for that derived from the blank inoculum run in parallel, was expressed as a percentage of the nominal DOC loading initially present. In order to check the procedure, sodium benzoate was used as a degradable reference item at a concentration of 20 mg/L, along with a toxicity control at 20 mg/L MDIPA-Esterquat C16-18 and C18 unsatd., and 20 mg/L sodium benzoate.


The degradation of MDIPA-Esterquat C16-18 and C18 unsatd. in the static test was found to be 60 % after 28 days. Biodegradation within the 10-day-window was found to be 40 % on the basis of the values obtained by measurement of the trap solutions in the course of the study and calculated to be 50 % assuming that the saturation of CO2 in the media found after acid dissolving at test end is stable after a few days of incubation.


With 40 % after 28 days, a significant abiotic degradation occurred.


The degradation of the reference substance sodium benzoate had reached 100 % within the first 14 days (103 % considering the medium fixed amount). The difference of extremes of replicate values of the removal of the test item at the end of the test is 14 %. Therefore, the test can be considered as valid.


No inhibitory effects of the test item were observed (more than 25% degradation occurred within 14 days) in the toxicity control.


 


The biodegradation of MDIPA-Esterquat C16-18 and C18 unsatd. was investigated over a 28-day period in a CO2 Evolution Test according to EC method C.4-C (2008) and OECD guideline 301 B (1992). The test medium was inoculated with microorganisms from a digester of a sewage treatment plant mainly fed with municipal wastewater.


The test solutions were aerated by the passage of CO2 free air at a controlled rate in closed flasks at 22±2°C for 28 days. The rate of degradation was monitored by measuring the carbon dioxide produced over the 28-d period. The amount of carbon dioxide produced by the microbial population during biodegradation of the test item at a concentration of 17 mg C/L, corrected for that derived from the blank inoculum run in parallel, was expressed as a percentage of the nominal TOC loading initially present. In order to check the procedure, sodium benzoate was used as a degradable reference item at a concentration of 20 mg DOC/L, along with a toxicity control at 17 mg TOC/L test item, and 20 mg DOC/L sodium benzoate.


The biodegradation of the test item was found to be 69% after 28 days. Degradation within the 10-day-window was found to be 36% on the basis of the values obtained by measurement of the trap solutions in the course of the study.


The degradation of the reference substance sodium benzoate had reached 95% within the first 14 days (actually within 11 days). The difference of extremes of replicate values of the removal of the test item at the end of the test is 5%. Therefore, the test can be considered as valid.


No inhibitory effects of the test item were observed (more than 25% degradation occurred within 14 days; 48% after 11 days of incubation) in the toxicity control.


MDIPA-Esterquat C16-18 and C18 unsatd. can be considered as being readily biodegradable but failing the 10-day-window under the test conditions of an OECD 301B test.


 


Although the 10-day window criterion is not fulfilled, the test substance can be regarded as readily biodegradable as it is a UVCB substance representing a complex multi-constituent substance with structurally similar constituents:


1.according to the REACH Guidance on information requirements and chemical safety assessment, Chapter R.7b: Endpoint specific guidance “These pass levels have to be reached in a 10-day window within the 28-day period of the test. The 10-day window does not apply to TG 301 C or if the test substance represents a mixture of homologous compounds e.g. technical surfactants."


2. according to CLP 7th ATP, 4.1.2.9.5.: "These levels of biodegradation must be achieved within 10 days of the start of degradation which point is taken as the time when 10 % of the substance has been degraded, unless the substance is identified as an UVCB or as a complex, multi-constituent substance with structurally similar constituents. In this case, and where there is sufficient justification, the 10-day window condition may be waived and the pass level applied at 28 days."


 


The biodegradation of MDIPA-Esterquat C16-18 and C18 unsatd. was investigated over a 28-day period in a Manometric Respirometry Test according to EC method C.4-D (2008) and OECD guideline 301 F (1992).


The test solutions were stirred in closed flasks at 22°C ± 1°C for 28 days. The rate of degradation was monitored by measuring the quantity of oxygen required to maintain a constant gas volume in the respirometer flasks over a 28-d period. The amount of oxygen taken up by the microbial population during biodegradation of the test item at a concentration of 460 mg/L (ThOD = 60 mg/L), corrected for uptake by the blank inoculum run in parallel, was expressed as a percentage of the ThOD (theoretical oxygen demand). In order to check the procedure, sodium benzoate was used as a degradable reference item at a concentration of 100 mg/L, along with a toxicity control at 460 mg/L test item and 100 mg/L sodium benzoate.


The biodegradation of the test item was found to be at mean 79% with a standard deviation of 6.7 % for a concentration of 460 mg test item per liter after 28 days. Biodegradation within the 10-day-window was found to be 65%. The 10-day-window started at day 2.


The degradation of the reference substance sodium benzoate had reached 85 % within the first 14 days. The difference of extremes of replicate values of the removal of the test item at the end of the test is less than 20%.Therefore, the test can be considered as valid.


The biodegradation of the item mixture in the toxicity control was found to be 75% after 14 days of incubation. Thus, the demanded threshold value of 25% is exceeded and the test item can be identified as non-toxic in a ready biodegradability test.


According to the OECD guideline 301F, MDIPA-Esterquat C16-18 and C18 unsatd. can be considered as being readily biodegradable under the chosen test conditions. 


 


Similar results were also obtained with the closely related source substance MDEA-Esterquat C16-18 and C18 unsatd.: 


The biodegradation of MDEA-Esterquat C16-18 and C18 unsatd. was studied in accordance with the OECD TG 301 B, and in compliance with GLP standards for 28 d. MDEA-Esterquat C16-18 and C18 unsatd. was applied at 2 concentration of 10 and 20 mg/L. CO2 production was analysed at 0, 1, 4, 5, 7, 8, 11, 14, 18, 22, and 28 days of incubation. The two test treatments (10 and 20 mg/L) reached > 60% CO2 production and met the 10 -day window. Therefore MDEA-Esterquat C16-18 and C18 unsatd. fulfills the OECD criteria of ready biodegradability.