1-Propanaminium, 2-hydroxy-N-(2-hydroxypropyl)-N,N-dimethyl-, esters with C18-unsatd. fatty acids, Me sulfates (salts)

Biodegradation in water: screening tests

Link to relevant study record(s)

Reference

Endpoint:

biodegradation in water: ready biodegradability

Type of information:

experimental study

Adequacy of study:

key study

Study period:

2015-06-11 to 2015-07-09

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

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

Version / remarks:

2008

Deviations:

no

Qualifier:

according to guideline

Guideline:

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

Version / remarks:

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history, procedure): sewage treatment plant Ruhrverband Kläranlage, Sunthelle 6, 57392 Schmallenberg, Germany; withdrawn on June 11th, 2015
- Storage conditions: kept aerobic until use
- Concentration of sludge: concentration used in the test was 29.7 mg dry mass/litre
- Type and size of filter used, if any:

Duration of test (contact time):

28 d

Initial conc.:

100 mg/L

Based on:

act. ingr.

Initial conc.:

24 mg/L

Based on:

act. ingr.

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°C ± 1°C
- pH: 7.4 ± 0.2
- pH adjusted: no
- Aeration of dilution water: yes
- Suspended solids concentration: 29.7 mg/L
- Continuous darkness: yes


TEST SYSTEM
- Culturing apparatus: closed 500 mL glass vessels at a medium volume of 250 mL
- Number of culture flasks/concentration: 2
- Method used to create aerobic conditions: aeration
- Measuring equipment: SAPROMAT respirometer (VOITH Inc.)
- Details of trap for CO2 and volatile organics if used: carbon dioxide is adsorbed in a suitable adsorbent
- Other: The consumption of oxygen is determined by measuring the quantity of oxygen (produced electrolytically) required to maintain constant gas volume in the respirometer flask.

SAMPLING
- Sampling frequency: measurement and recording of the oxygen demand was carried out continuously
- At test end, NH3-N and NO3-N concentrations were measured in control, test item and abiotic control assays.

CONTROL AND BLANK SYSTEM
Blank control: The blank control consists of inoculated mineral medium only.
Abiotic control: An abiotic control containing test item at 100 mg per litre sterilized mineral test medium (25 mg/250 mL) was applied. The assay was sterilized by adding HgCl2.
Procedural control: A procedural control containing sodium benzoate as reference item at 100 mg per litre mineral test medium (25 mg/250 mL) was applied.
Toxicity control: A toxicity control containing test item at 100 mg per litre and reference item at 100 mg per litre mineral test medium (25 mg/250 mL) was applied.


STATISTICAL METHODS:

Reference substance:

benzoic acid, sodium salt

Remarks:

100 mg/L

Parameter:

% degradation (O2 consumption)

Value:

63

St. dev.:

1

Sampling time:

14 d

Remarks on result:

other: 24 mg/L

Parameter:

% degradation (O2 consumption)

Value:

74

St. dev.:

0

Sampling time:

28 d

Remarks on result:

other: 24 mg/L

Parameter:

% degradation (O2 consumption)

Value:

42

St. dev.:

6

Sampling time:

14 d

Remarks on result:

other: 100 mg/L

Parameter:

% degradation (O2 consumption)

Value:

60

St. dev.:

6

Sampling time:

28 d

Remarks on result:

other: 100 mg/L

Details on results:

With 0 %, nitrification of test item originated nitrogen can be neglected. Therefore, mineralization of the test item should be evaluated on the basis of ThOD NH3. The biodegradation of the test item after 28 days of incubation in the static test was found to be 60 % (SD = 6.0 %) in the assays with 100 mg/L and 74 % (SD = 0.0 %) in the assays with 24 mg/L based on ThOD NH3.
Biodegradation on the basis of ThODNH3 at the end of the 10-day-window was found to be 42 % in the assays with 100 mg/L and 60 % in the assays with 24 mg/L. The 10-day-window started on day 2 – 3, depending on the concentration.
With 0 %, there was no abiotic degradation of the test item noticeable within the 28 days of incubation. The biodegradation of the item mixture in the toxicity control was found to be 23 % after 14 days of incubation. Thus, the demanded threshold value of 25 % is undercut. Nevertheless, due to comparable absolute oxygen demand to the reference assays, and test assays surpassing the threshold value of 60 % degradation within a 10-day-window, the test item can be identified as being non-toxic in a ready biodegradability test.

Results with reference substance:

The reference item sodium benzoate was degraded to 91 % within the first 14 days.

Nitrification after 28 days (% of test item originated N): Single and mean values of the parallel test vessels and standard deviation.

vessel	Test suspension A	Test suspension B
1	> -9.9	0.0
2	> -9.9	> -41.1
Mean	> -9.9	> -20.5
SD	0.0	> 29.1

 

Oxygen consumption. Cumulated consumption (mg O₂/L) after 14 days: Single and mean values of the parallel test vessels and standard deviation. Test suspension A, abiotic and procedural control: 100 mg/L; Test suspension B: 24 mg/L;Toxicity control: 200 mg/L.

vessel	Inoculum blank	Test suspension A	Test suspension B	Procedural control	Toxicity control	Abiotic control
1	12	106	50	165	107	0
2	14	126	51	-	110	0
Mean	13	116	51	165	109	0
SD	1	14	1	-	2	0

 

Oxygen consumption. Cumulated consumption (mg O₂/L) after 28 days: Single and mean values of the parallel test vessels and standard deviation. Test suspension A, abiotic and procedural control: 100 mg/L; Test suspension B: 24 mg/L;Toxicity control: 200 mg/L.

vessel	Inoculum blank	Test suspension A	Test suspension B	Procedural control	Toxicity control	Abiotic control
1	17	156	62	181	158	0
2	19	177	62	-	165	1
Mean	18	167	62	181	162	1
SD	1	15	0	-	5	1

 

Percent degradation. Degradation (% based on ThOD_NH3) after 14 days: Single and mean values of the parallel test vessels and standard deviation.

vessel	Test suspension A	Test suspension B	Procedural control	Toxicity control	Abiotic control
1	38	62	91	23	0
2	46	64	-	23	0
Mean	42	63	91	23	0
SD	6	1	-	1	0

 

Percent degradation. Degradation (% based on ThOD_NH3) after 28 days: Single and mean values of the parallel test vessels and standard deviation.

vessel	Test suspension A	Test suspension B	Procedural control	Toxicity control	Abiotic control
1	56	74	98	34	0
2	64	74	-	36	0
Mean	60	74	98	35	0
SD	6	0	-	1	0

 

Validity criteria fulfilled:

yes

Interpretation of results:

readily biodegradable

Conclusions:

In this test, MDIPA Esterquat C18 unsatd. was readily biodegradable an fulfilled the 10 day window criterion.

Executive summary:

The biodegradation of MDIPA Esterquat C18 unsatd. (98.8% a.i.) was investigated in a study conducted according to OECD Guideline 301 F, adopted 17th July 1992 (Ready Biodegradability: Manometric Respirometry Test) and EU Method C.4-D, 2008, over a period of 28 days using activated sludge sampled from a sewage treatment plant mainly fed with municipal wastewater as inoculum. The biodegradation rate was determined by measurement of O2 consumption. Inoculum blank, toxicity control and procedural/functional control with the reference substance Sodium benzoate were performed. The test was performed with 24 and 100 mg/L test substance concentration.The functional control reached the pass level >60% after 14 d (91%).

With 0%, nitrification of test item originated nitrogen can be neglected. Therefore, mineralization of the test item was evaluated on the basis of ThOD NH3. The biodegradation of the test item after 28 days of incubation in the static test was found to be 60% (SD = 6.0 %) in the assays with 100 mg/L and 74% (SD = 0.0%) in the assays with 24 mg/L based on ThOD NH3. Biodegradation on the basis of ThODNH3 at the end of the 10-day-window was found to be 42% in the assays with 100 mg/L and 60% in the assays with 24 mg/L. The 10-day-window started on day 2 – 3, depending on the concentration. With 0%, there was no abiotic degradation of the test item noticeable within the 28 days of incubation. The biodegradation of the item mixture in the toxicity control was found to be 23% after 14 days of incubation. Thus, the demanded threshold value of 25% is undercut. Nevertheless, due to comparable absolute oxygen demand to the reference assays, and test assays surpassing the threshold value of 60% degradation within a 10-day-window, the test item can be identified as being non-toxic in a ready biodegradability test.

In this test, MDIPA Esterquat C18 unsatd. was readily biodegradable.

Description of key information

MDIPA Esterquat C18 unsatd. is readily biodegradable (OECD guideline 301 F/EU method C.4-D).

Key value for chemical safety assessment

Biodegradation in water:

readily biodegradable

Type of water:

freshwater

Additional information

The biodegradation of MDIPA Esterquat C18 unsatd. (98.8% a.i.) was investigated in a study conducted according to OECD Guideline 301 F, adopted 17th July 1992 (Ready Biodegradability: Manometric Respirometry Test) and EU Method C.4-D, 2008, over a period of 28 days using activated sludge sampled from a sewage treatment plant mainly fed with municipal wastewater as inoculum. The biodegradation rate was determined by measurement of O2 consumption. Inoculum blank, toxicity control and procedural/functional control with the reference substance Sodium benzoate were performed. The test was performed with 24 and 100 mg/L test substance concentration.The functional control reached the pass level >60% after 14 d (91%).

With 0%, nitrification of test item originated nitrogen can be neglected. Therefore, mineralization of the test item was evaluated on the basis of ThOD NH3. The biodegradation of the test item after 28 days of incubation in the static test was found to be 60% (SD = 6.0 %) in the assays with 100 mg/L and 74% (SD = 0.0%) in the assays with 24 mg/L based on ThOD NH3. Biodegradation on the basis of ThODNH3 at the end of the 10-day-window was found to be 42% in the assays with 100 mg/L and 60% in the assays with 24 mg/L. The 10-day-window started on day 2 – 3, depending on the concentration. With 0%, there was no abiotic degradation of the test item noticeable within the 28 days of incubation. The biodegradation of the item mixture in the toxicity control was found to be 23% after 14 days of incubation. Thus, the demanded threshold value of 25% is undercut. Nevertheless, due to comparable absolute oxygen demand to the reference assays, and test assays surpassing the threshold value of 60% degradation within a 10-day-window, the test item can be identified as being non-toxic in a ready biodegradability test.

In this test, MDIPA Esterquat C18 unsatd. was readily biodegradable.

 

A further study on the biodegradation of MDIPA Esterquat C18 unsatd. is available:

The biodegradation of MDIPA Esterquat C18 unsatd. (99.0% a.i.) was investigated in a study conducted according to OECD Guideline 301 F, adopted 17th July 1992 (Ready Biodegradability: Manometric Respirometry Test) and EU Method C.4-D, December 1992, over a period of 28 days using activated sludge sampled from a sewage treatment plant mainly fed with municipal wastewater as inoculum. The biodegradation rate was determined by measurement of O2 consumption. Inoculum blank, toxicity control and procedural/functional control with the reference substance Sodium benzoate were performed. The test was performed with 50 and 100 mg/L test substance concentration.The functional control reached the pass level >60% after 14 d (88%).

The biodegradation of the test substance was 77% (at 50 mg/L) and 49% (at 100 mg /L) after 28 days. The 10-day window started at day two and three, respectively. The biodegradation within the 10-day-window was 50% and 34%, respectively.

In the toxicity controls the biodegradation was found to be 58% and 38%, respectively, after 14 days of incubation. Thus, the demanded threshold value of 25% is exceeded and the test item can be identified as not inhibitory to microorganisms.

Due to a high COD of 2.29 mg O2/mg test item, the test item suspension with a concentration of 50 mg/L met the criteria of 50 - 100 mg ThOD or COD/L, as demanded in the guideline. At a concentration of 50 mg/L, the test item obtained a biodegradation above 60% within the test duration.

Although the 10 day window criterion is not fulfilled, the test substance can be regarded as readily biodegradable according to theGuidance 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.”

In this test, MDIPA Esterquat C18 unsatd. was readily biodegradable.

 

Similar results were obtained with the closely related read-across substances MDEA-Esterquat C16-18 and C18 unsatd. and MDEA-Esterquat C16-18 and C18 unsatd.:

The biodegradation of MDEA-EsterquatC16-18 and C18 unsatd. was studied in accordance with the OECD TG 301 B 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.

 

The biodegradation of MDIPA-Esterquat C16-18 and C18 unsatd. was investigated over a 28-day period in a Manometric Respirometry Test according to OECD guideline 301 F for 28 d. 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 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.