N-(3-aminopropyl)-N-dodecylpropane-1,3-diamine

Biodegradation in water: screening tests

Link to relevant study record(s)

Reference

Reference 1

Endpoint:

biodegradation in water: screening tests

Type of information:

experimental study

Adequacy of study:

key study

Study period:

From March 06, 2014 to April 10, 2014

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

other: OECD 306 guideline for testing of chemicals (1992) Biodegradability in seawater

Deviations:

yes

Remarks:

acceptable deviations

Principles of method if other than guideline:

Minor deviations from the guidelines were introduced: a) ammonium chloride was omitted from the medium to prevent oxygen consumption due to nitrification (omission does not result in nitrogen limitation as shown by the biodegradation of the reference compound) and b) the oxygen consumption was measured at Day 0, 7, 14, 21, and 28 instead of Day 5, 15, and 28.

GLP compliance:

yes (incl. QA statement)

Specific details on test material used for the study:

Name: N-(3-aminopropyl)-N-dodecylpropane-1,3-diamine
CAS No.: 2372-82-9
Batch/lot No. S003164
Purity 99.9%
Water 0.1%

Oxygen conditions:

aerobic

Inoculum or test system:

other: seawater

Details on inoculum:

Seawater was collected from coastal water near the Oosterscheldedam (Banjaard, The Netherlands) at high tide (06-03-2014).
The seawater was sampled approximately 10 cm below the water surface. The temperature of the water was 7.8C. The seawater was slightly
turbid. The seawater was aged to reduce the concentration of biodegradable compounds present in the seawater.
To this end, the seawater was aerated for 7 days.

Duration of test (contact time):

28 d

Initial conc.:

2 mg/L

Based on:

test mat.

Parameter followed for biodegradation estimation:

O2 consumption

Details on study design:

Test bottles
The test was performed in 0.3 litre BOD (biological oxygen demand) bottles with glass stoppers.

Nutrient solution and stock solutions
The seawater in the Closed Bottle test contained per liter additional nutrients: 8.5 mg KH2PO4, 21.75 mg K2HPO4, 33.3 mg Na2HPO4·2H2O, 22.5 mg MgSO4·7H2O, 27.5 mg CaCl2, 0.25 mg FeCl3·6H2O. Ammonium chloride was omitted from the medium to prevent nitrification. Due to this omission the pH of the medium decreased slightly. Sodium acetate and the test substance were added to the bottles using stock solutions of 1.0 g/L.

Test procedures
The Closed Bottle test was performed according to the study plan, developed from the OECD Test Guideline (1992). Use was made of 10 bottles containing only seawater as inoculum, 10 bottles containing test substance and seawater, and 10 bottles containing sodium acetate and
seawater. The concentrations of the test substance and sodium acetate in the bottles were 2.0 mg/L. Each of the prepared solutions in seawater was dispensed into the respective group of BOD bottles so that all bottles were completely filled without air bubbles. The zero time bottles were immediately analyzed for dissolved oxygen using an oxygen electrode. The remaining bottles were closed and incubated at 18°C ± 2°C in the dark. Two duplicate bottles of all series were withdrawn for analyses of the dissolved oxygen concentration at Day 7, 14, 21, and 28.

Reference substance:

acetic acid, sodium salt

Remarks:

purity >99% ; batch/lot No. 050M0213V

Test performance:

Toxicity
Inhibition of the degradation of a well-degradable compound, e.g. sodium acetate by the test substance in the Closed Bottle test was not determined because possible toxicity of N-(3-aminopropyl)-N-dodecylpropane-1,3-diamine to microorganisms degrading acetate is not relevant. Inhibition of the endogenous respiration of the inoculum by the test substance in the presence of humic acid was not detected. Therefore, no inhibition of the biodegradation due to
the "high" initial concentration of the test substance is expected.

Seawater and test conditions
The seawater was slightly turbid. The concentrations of PO4 3- , NO3-, and NH4+ in the seawater used as inoculum were <0.15 mg/L, <1.0 mg/L and <0.02 mg/L, respectively. The seawater contained 3.1% salt. The nonpurgeable organic carbon content was 1.1 mg/L. The pH of the aged seawater at the start of the test was 8.0. At Day 28 of the Closed Bottle test the pH of the media was 7.9 (test), 8.0 (controls and reference). Temperatures ranged from 17 to 19°C.

Validity of the test
The validity of the test is demonstrated by an endogenous respiration of 0.7 mg/L at day 28 (Table II). The blank respiration therefore does not exceed 30% of the oxygen in the test bottles. Sodium acetate was degraded by 76% of its theoretical oxygen demand after 28 days (Table III). The validity of the test is also shown by oxygen concentrations >0.5 mg/L in all bottles during the test period (Table II).

Key result

Parameter:

% degradation (O2 consumption)

Value:

68

Sampling time:

28 d

Details on results:

Calculated THOD N-(3-aminopropyl)-N-dodecylpropane-1,3-diamine = 2.8 mg/mg
Calculated THOD sodium acetate = 0.8 mg/mg

The validity of the test is demonstrated by an endogenous respiration of 0.9 mg/L at day 28 (Table I). Furthermore, the differences of the replicate values at day 28 were less than 20%. The biodegradation percentage of the reference compound, sodium acetate, at day 14 was 81. Finally, the validity of the test is shown by oxygen concentrations >0.5 mg/L in all bottles during the test period

Table II Dissolved oxygen concentrations (mg/L) in the closed bottles.

Time		Oxygen concentration (mg/L)
		Ocs	Ot	Oc	Oa
Day 0	Replicate 1	7.2	7.2	7.2	7.2
	Replicate 2	7.2	7.2	7.2	7.2
	Mean	7.2	7.2	7.2	7.2
Day 7	Replicate 1	7	6.6	7	3.1
	Replicate 2	7	6.6	7	3.3
	Mean	7	6.6	7	3.2
Day 14	Replicate 1	6.9	4.8	6.8	3
	Replicate 2	6.8	4.4	6.9	2.9
	Mean	6.9	4.6	6.9	3
Day 21	Replicate 1	6.9	3.9	6.8	2.8
	Replicate 2	6.8	4.2	6.7	2.6
	Mean	6.9	4.1	6.8	2.7
Day 28	Replicate 1	6.5	2.8	6.4	2.3
	Replicate 2	6.6	2.7	6.5	2.4
	Mean	6.6	2.8	6.5	2.4

Ocs Sea water with nutrients without test material but with humic acid (2.0 mg/L).

Ot Seawater with nutrients, test material (2.0 mg/L), and humic acid (2.0 mg/L).

Oc Seawater with nutrients.

Oa Seawater with nutrients and sodium acetate (6.7 mg/L).

Table III Oxygen consumption (mg/L) and the percentages biodegradation of N-(3 -aminopropyl)-N-dodecylpropane-1,3-diamine (BOD/ThOD) and sodium acetate (BOD/ThOD)

in the Closed Bottle test.

Time (days)	Oxygen consumption (mg/L)		Biodegradation (%)
	Test	Acetate	Test	Acetate
0	0.0	0.0	0	0
7	0.4	3.8	7	70
14	2.3	3.9	41	72
21	2.8	4.1	50	76
28	3.8	4.1	68	76

Validity criteria fulfilled:

yes

Remarks:

The blank respiration therefore does not exceed 30% of the oxygen in the test bottles. 76% degradation of sodium acetate at day 28. Oxygen concentration >0.5 mg/L in bottles during test

Interpretation of results:

readily biodegradable

Conclusions:

Under the study conditions, the test substance was considered to be readily biodegradable in seawater.

Executive summary:

A study was conducted to determine the biotic degradation of the test substance in seawater according to a slightly modified Closed Bottle method (OECD Guideline 306), in compliance with GLP. The test substance did not cause a reduction in the endogenous respiration. It was therefore considered to be non-inhibitory to the inoculum. The test substance was biodegraded by 68% on Day 28. The test was valid as shown by an endogenous respiration of 0.7 mg/L and by the total mineralization of the reference compound, sodium acetate. Finally, the most important criterion was met by oxygen concentrations >0.5 mg/L in all bottles during the test period. Under the study conditions, the test substance was considered to be readily biodegradable in seawater (van Ginkel, 2014).

Reference 2

Endpoint:

biodegradation in water: ready biodegradability

Type of information:

experimental study

Adequacy of study:

supporting study

Study period:

2001

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)

GLP compliance:

yes

Oxygen conditions:

aerobic

Inoculum or test system:

activated sludge, domestic (adaptation not specified)

Duration of test (contact time):

28 d

Initial conc.:

5 mg/L

Based on:

other: carbon

Parameter followed for biodegradation estimation:

CO2 evolution

Key result

Parameter:

% degradation (CO2 evolution)

Value:

0

Sampling time:

28 d

Details on results:

The test substance caused a significant inhibition of the microbial inoculum and, therefore, a reliable prediction of the biodegradability cannot be made. The total CO2 evolution in the control vessels on day 28 was 30.95 mg/L and satisfied the validation criterion given in the OECD guideline. The IC/TC ratio of the test material suspension in the substance medium at the start of the test was below 5% and hence satisfied the validation criterion given in the OECD guideline. The difference between the values for CO2 production at the end of the test for the replicate vessels was < 20% and hence satisfied the validation criterion in the OECD guideline.

Applying the general OECD guideline criteria for assessing toxicity of the test substance to the microbial inoculum (see above), the test substance is considered not to have an inhibitory effect. However, if the individual values of the CO2 evolution of the test vessels are compared to the blank values, a significant inhibition of the microbial population by the test substance was observed. This is reflected by the negative degradation values, which can theoretically be calculated from the single measurements. An increasing inhibition up to approximately “-50 % degradation” was observed from the start of the test which continued throughout the whole incubation period. In other words, in such a case an inhibition of the basic respiration of the micro-organisms is observed (as compared to the blanks) and it can be concluded that this toxic effect have a significant impact on the physiological condition of the population precluding a biodegradation of the test substance.

Validity criteria fulfilled:

yes

Interpretation of results:

other: a reliable prediction of the biodegradability could not be made

Remarks:

(very high initial test substance concentration and the significant inhibition of microbial inoculum)

Conclusions:

Under the study conditions, the study authors concluded that test substance was not readily biodegradable. However, given the high initial test substance concentration and the significant inhibition of microbial inoculum observed, the results of this study are not considered representative of the degradation of the substance. .

Executive summary:

A study was conducted to evaluate the ready biodegradability of the test substance in water according to OECD Guideline 301 B, in compliance with GLP. The aerobic elimination and degradation potential was evaluated throughout a 28 d period in an activated sludge, domestic (adaptation not specified) model. The test substance was used at an initial concentration of 5.0 mg C/L. The test substance caused a significant inhibition of the microbial inoculum in this test and, therefore, a reliable prediction of the biodegradability could not be made. The total CO2 evolution in the control vessels on Day 28 was 30.95 mg/L and therefore satisfied the validation criterion given in the OECD guideline. The IC/TC ratio of the test substance suspension in the mineral medium at the start of the test was below 5% and hence satisfied the validation criterion. The difference between the values for CO2 production at the end of the test for the replicate vessels was <20%. Under the study conditions, the study authors concluded that test substance was not readily biodegradable (Clarke, 2001).

Reference 3

Endpoint:

biodegradation in water: ready biodegradability

Type of information:

experimental study

Adequacy of study:

key study

Study period:

From May 29, 2002 to June 26, 2002

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

OECD Guideline 301 D (Ready Biodegradability: Closed Bottle Test)

Deviations:

yes

Remarks:

1 mg/L test substance was used and the test temperature ranged from 19 – 21°C

GLP compliance:

yes

Specific details on test material used for the study:

The calculated theoretical oxygen demand of the test substance is 2.8 mg/mg. The theoretical oxygen demand of sodium acetate is 0.8 mg/mg.

Oxygen conditions:

aerobic

Inoculum or test system:

sewage, predominantly domestic, non-adapted

Details on inoculum:

The inoculum was obtained from a pristine ditch in Arnhem-Zuid, The Netherlands (22.05.02). The ditch water was preconditioned to reduce the endogenous respiration rates. The endogenous respiration was reduced through aeration for a period of one week. The ditch water was diluted (100 mL/L) in the closed bottle.

For the test the validity criteria ≤ 1.5 mg/L oxygen consumption in the control group at Day 28 in the Closed Bottle test demonstrated that a small inoculum was used. This criteria fulfilment indicates low endogenous respiration, which is due to presence of small amount of inoculum. Further, the ditch water used was not pre-exposed to the test substance after sampling.

Duration of test (contact time):

28 d

Initial conc.:

1 mg/L

Based on:

test mat.

Parameter followed for biodegradation estimation:

O2 consumption

Details on study design:

Test procedures:
- The closed bottle test was performed according to the study plan. The study plan was developed from IS0 Test Guidelines (ISO).
- Test bottles: The test was performed in 250 to 300 mL BOD (biological oxygen demand) bottles with glass stoppers.
- Use was made of 10 bottles containing only inoculum (inoculum control), 10 bottles containing test substance and inoculum, and 6 bottles containing sodium acetate and inoculum (reference control).
- The concentrations of the test compound and sodium acetate in the bottles were 1.0 and 6.7 mg/L, respectively. The inoculum was diluted to 2 mg DW/L in the closed bottles. Each of the prepared solutions was dispensed into the respective group of BOD bottles so that all bottles were completely filled without air bubbles.
- The zero time bottles were immediately analyzed for dissolved oxygen using an oxygen electrode. The remaining bottles were closed and incubated in the dark.
- Two duplicate bottles of all series were withdrawn for analyses of the dissolved oxygen concentration at Day 7, 14, 21, and 28.

Nutrient solution and stock solutions:
- The nutrient medium of the closed bottle test contained per liter of deionized water: 8.5 mg KH2PO4, 21.75 mg K2HPO4, 33.3 mg Na2HPO4.2H2O, 22.5 mg MgSO4.7H20, 27.5 mg CaCI2, 0.25 mg FeCl3.6H2O. Ammonium chloride was omitted from the medium to prevent nitrification. Due to this omission the pH of the medium decreased slightly. The decrease of the pH does not affect the biodegradation in the closed bottle test.
- Sodium acetate was added to the bottles using a stock solution of 1.0 g/L. The test compound was added to the bottles using a stock solution of l. 2 g/L.

Reference substance:

acetic acid, sodium salt

Remarks:

Sodium acetate anhydrous (6.7 mg/L)

Key result

Parameter:

other: Biochemical oxygen demand

Value:

79

Sampling time:

28 d

Details on results:

Toxicity
Inhibition of the degradation of a well-degradable compound, e.g. sodium acetate by the test compound in the Closed Bottle test was not determined because possible toxicity of Triamine Y12D to microorganisms degrading acetate is not relevant. Inhibition of the endogenous respiration of the inoculum by the test substance at 1 mg/L was not detected. Therefore, no inhibition of the biodegradation due to the "high" initial concentration of the test compound is expected.

Test conditions
The pH of the media was 7.4 – 7.6 at the start of the test. The pH of the medium at day 28 was 7.0 – 7.1. Tem¬peratures ranged from 19 to 21°C.

Validity of the test
The validity of the test is demonstrated by an endogenous respiration of 0.6 mg/L at day 28 (Ta¬ble I). Furthermore, the differences of the replicate values at day 28 were less than 20%. The biodegradation percentage of the reference compound, sodium acetate, at day 14 was 76. Finally, the validity of the test is shown by oxygen concentrations >0.5 mg/L in all bottles during the test period.

The Closed Bottle test
Triamine Y12D is biodegraded 79% at day 28 in the Closed Bottle test (Figure and Tables I-II), and should therefore be classified as readily biodegradable.

Results with reference substance:

The percentage biodegradation of the reference compound, sodium acetate, at Day 14, was 76%.

The validity of the test was demonstrated by an endogenous respiration of 0.6 mg/L at Day 28. Furthermore, the differences of the replicate values at Day 28 were less than 20%. Finally, the validity of the test was shown by oxygen concentrations >0.5 mg/L in all bottles during the test period.

Table I Dissolved oxygen concentrations (mg/L) in the closed bottles.

Time (days)	Oxygen concentration (mg/L)
	Oc	Ot	Oa
0	8.8	8.8	8.8
	8.8	8.8	8.8
Mean (M)	8.8	8.8	8.8
7	8.6	8.0	5.0
	8.6	8.0	4.9
Mean (M)	8.6	8.0	5.0
14	8.4	6.8	4.4
	8.5	6.7	4.3
Mean (M)	8.5	6.8	4.4
21	8.3	6.2
	8.2	6.3
Mean (M)	8.3	6.3
28	8.2	5.9
	8.1	6.0
Mean (M)	8.2	6.0

 

O_c   = Mineral nutrient solution without test material but with inoculum.

O_t   = Mineral nutrient solution with test material (1 mg/L), and with inoculum.

O_a  = Mineral nutrient solution with sodium acetate (6.7 mg/L) and with inoculum.

 

 

Table II Oxygen consumption (mg/L) and the percentages biodegradation of Triamine Y12D (BOD/ThOD) and sodium acetate (BOD/ThOD)in the Closed Bottle test.

 

Time (days)	Oxygen consumption (mg/L)		Biodegradation (%)
	Test	Acetate	Test	Acetate
0	0.0	0.0	0	0
7	0.6	3.6	21	67
14	1.7	4.1	61	76
21	2.0		71
28	2.1		79

 

Validity criteria fulfilled:

yes

Interpretation of results:

readily biodegradable

Conclusions:

Under the study conditions, the test substance was considered to be readily biodegradable with 79% biodegradation on Day 28.

Executive summary:

A study was conducted to determine ready biodegradability of the test substance in a closed bottle test according to OECD Guideline 301 D, in compliance with GLP. The test substance at 1 mg/L was incubated with non-adapted activated sludge (from ditch water) and placed in closed bottles in the dark for 28 d. Degradation was assessed by determination of the dissolved oxygen concentration (DOC) on Days 7, 14, 21 and 28. Control solutions containing the reference substance, sodium acetate (6.7 mg/L), together with inoculum and inhibition controls, were used for validation purposes. The test substance biodegraded 21, 61, 71 and 79% on Day 7, 14, 21 and 28, respectively, and fulfilled the 10 d window criteria. The theoretical oxygen demand (ThOD) of the test substance was 2.8 mg/mg. The validity of the test was demonstrated by an endogenous respiration of 0.6 mg/L on Day 28. Furthermore, the differences of the replicate values on Day 28 were lower than 20%. The biodegradation percentage of the reference compound, sodium acetate, on Day 14 was 76%. Finally, the validity of the study was shown by oxygen concentrations >0.5 mg/L in all bottles during the test period. Under the study conditions, the test substance was considered to be readily biodegradable (Garttener, 2002).

Reference 4

Endpoint:

biodegradation in water: inherent biodegradability

Type of information:

experimental study

Adequacy of study:

supporting study

Study period:

1997

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

other: OECD 302B and 301A

Deviations:

yes

Remarks:

The inherent biodegradation study was run as the initial step for obtaining pre-adapted sludge for a study to OECD guideline 301A.

Principles of method if other than guideline:

The inherent biodegradation study was run as the initial step for obtaining pre-adapted sludge for a study to OECD guideline 301A. Biodegradation using pre-adapted inoculum may not be termed ready biodegradation, hence the subsequent OECD 301A study performed is not considered valid for ready biodegradation.

GLP compliance:

yes

Oxygen conditions:

aerobic

Inoculum or test system:

sewage, predominantly domestic, adapted

Duration of test (contact time):

28 d

Parameter followed for biodegradation estimation:

DOC removal

Key result

Parameter:

% degradation (DOC removal)

Value:

91

Sampling time:

28 d

Validity criteria fulfilled:

yes

Interpretation of results:

inherently biodegradable

Conclusions:

Under the study conditions, the test substance was inherently biodegradable (91% degradation (DOC removal) in 28 d).

Executive summary:

A study was conducted to evaluate the ready biodegradability of the test substance in water according to OECD Guidelines 302 B and 301 A, in compliance with GLP. The inherent biodegradation study was run as the initial step for obtaining pre-adapted sludge for a study according to OECD Guideline 301 A. Biodegradation using pre-adapted inoculum may not be termed ready biodegradation, hence the subsequent OECD 301 A study performed was not considered valid for ready biodegradation evaluation. OECD Guideline 302 B was therefore used. This study was performed in order to evaluate aerobic elimination and degradation potential of the test substance throughout a 28 d period in an activated domestic sludge model that was previously pre-adapted. The study indicated that the validation criteria of OECD 302 B were fulfilled. Under the study conditions, the test substance was inherently biodegradable (91% degradation (DOC removal) in 28 d) (Hirschen, 1997).

Key value for chemical safety assessment

Biodegradation in water:

readily biodegradable

Type of water:

other: Observed to be readily biodegradable in both marine and fresh water conditions

Additional information

A study was conducted to determine ready biodegradability of the test substance in a closed bottle test according to OECD Guideline 301 D, in compliance with GLP. The test substance at 1 mg/L was incubated with non-adapted activated sludge (from ditch water) and placed in closed bottles in the dark for 28 d. Degradation was assessed by determination of the dissolved oxygen concentration (DOC) on Days 7, 14, 21 and 28. Control solutions containing the reference substance, sodium acetate (6.7 mg/L), together with inoculum and inhibition controls, were used for validation purposes. The test substance biodegraded 21, 61, 71 and 79% on Day 7, 14, 21 and 28, respectively, and fulfilled the 10 d window criteria. The theoretical oxygen demand (ThOD) of the test substance was 2.8 mg/mg. The validity of the test was demonstrated by an endogenous respiration of 0.6 mg/L on Day 28. Furthermore, the differences of the replicate values on Day 28 were lower than 20%. The biodegradation percentage of the reference compound, sodium acetate, on Day 14 was 76%. Finally, the validity of the study was shown by oxygen concentrations >0.5 mg/L in all bottles during the test period. Under the study conditions, the test substance was considered to be readily biodegradable (Garttener, 2002).

A study was conducted to determine the biotic degradation of the test substance in seawater according to a slightly modified Closed Bottle method (OECD Guideline 306), in compliance with GLP. The test substance did not cause a reduction in the endogenous respiration. It was therefore considered to be non-inhibitory to the inoculum. The test substance was biodegraded by 68% on Day 28. The test was valid as shown by an endogenous respiration of 0.7 mg/L and by the total mineralization of the reference compound, sodium acetate. Finally, the most important criterion was met by oxygen concentrations >0.5 mg/L in all bottles during the test period. Under the study conditions, the test substance was considered to be readily biodegradable in seawater (van Ginkel, 2014).

A study was conducted to evaluate the ready biodegradability of the test substance in water according to OECD Guidelines 302 B and 301 A, in compliance with GLP. The inherent biodegradation study was run as the initial step for obtaining pre-adapted sludge for a study according to OECD Guideline 301 A. Biodegradation using pre-adapted inoculum may not be termed ready biodegradation, hence the subsequent OECD 301 A study performed was not considered valid for ready biodegradation evaluation. OECD Guideline 302 B was therefore used. This study was performed in order to evaluate aerobic elimination and degradation potential of the test substance throughout a 28 d period in an activated domestic sludge model that was previously pre-adapted. The study indicated that the validation criteria of OECD 302 B were fulfilled. Under the study conditions, the test substance was inherently biodegradable (91% degradation (DOC removal) in 28 d) (Hirschen, 1997).

A study was conducted to evaluate the ready biodegradability of the test substance in water according to OECD Guideline 301 B, in compliance with GLP. The aerobic elimination and degradation potential was evaluated throughout a 28 d period in an activated sludge, domestic (adaptation not specified) model. The test substance was used at an initial concentration of 5.0 mg C/L. The test substance caused a significant inhibition of the microbial inoculum in this test and, therefore, a reliable prediction of the biodegradability could not be made. The total CO2 evolution in the control vessels on Day 28 was 30.95 mg/L and therefore satisfied the validation criterion given in the OECD guideline. The IC/TC ratio of the test substance suspension in the mineral medium at the start of the test was below 5% and hence satisfied the validation criterion. The difference between the values for CO2 production at the end of the test for the replicate vessels was <20%. Under the study conditions, the study authors concluded that test substance was not readily biodegradable (Clarke, 2001).

It should be noted that, due to its known biocidal properties, the test substance mayinhibit growth in ready biodegradability testing at high initial concentrations (van Ginkel, 1995). Concentrations of 2 mg/L of test substance are prescribed in the Closed Bottle test (OECD 301 D and 306), which is very low compared to the initial concentrations used in other ready biodegradability tests. The Closed Bottle test is therefore a superior test for alkyl-1,3-diaminopropanes. The setup of ready biodegradability tests with higher initial concentrations, such as that of Clarke (2001), may therefore not necessarily reflect the bio­degradation potential ofN-(3-aminopropyl)-N-dodecylpropane-1,3-diamine.

Overall, the weight of evidence therefore suggests that the test substance is readily biodegradable.

Reference

Van Ginkel CG (1995). Biodegradation of cationic surfactants. In: Biodegradation of surfactants. Eds M.R. Porter and R. Karsa In Blackie Academic & Professional, pp. 183 203.

[Type of water: freshwater]