N-(3-aminopropyl)-N- (C12-18 even numbered) alkyl-propane-1,3-diamine

Biodegradation in water: screening tests

Administrative data

Endpoint:

biodegradation in water: ready biodegradability

Type of information:

experimental study

Adequacy of study:

key study

Study period:

2009-07-17 - 2009-08-21

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: Test performed under GLP according guidelines with acceptable (minor) deviations, meeting all validity criteria.

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2009

Report date:

2009

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

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

Deviations:

yes

Remarks:

accetable deviations

Principles of method if other than guideline:

Minor deviations from the guidelines of the Closed Bottle test were introduced; a) ammonium chloride was not added 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) river water was used as inoculum

GLP compliance:

yes (incl. QA statement)

Test material

Test material information

Constituent 1

Reference substance name:

91771-18-5

Cas Number:

91771-18-5

IUPAC Name:

91771-18-5

Constituent 2

Reference substance name:

Amines, N-(3-aminopropyl)-N (or N')-coco alkyltrimethylenedi-

EC Number:

294-908-6

EC Name:

Amines, N-(3-aminopropyl)-N (or N')-coco alkyltrimethylenedi-

IUPAC Name:

294-908-6

Details on test material:

A sample of coco dipropylene triamine was received from Akzo Nobel Surface Chemistry on 11-06-2009. The following test substance data were submitted by the sponsor, who accepted full responsibility for the validity thereof.
• chemical name (active ingredient): coco dipropylene triamine
• CAS reg. No. (active ingredient): 91771-18-5
• Composition (see annex 2)
coco dipropylene triamine (70.6%)
coco propylene diamine (22%)
coco propylene tetramine (5.1%)
coco amine (2.3%)
• product name: Triameen C
• batch/lot No. S001254
• appearance: yellowish liquid
• stability not relevant
• solubility in water: soluble at test concentrations
• storage at ambient temperature in the dark under nitrogen gas

The concentrations cited in this report refer to the as-received sample of coco dipropylene triamine.

Study design

Oxygen conditions:

aerobic

Inoculum or test system:

natural water

Details on inoculum:

River water was sampled from the Rhine near Heveadorp, The Netherlands 17-07-2009).
The river water was aerated for 7 days before use to reduce the endogenous respiration (van Ginkel and Stroo, 1992).
River water without particles was used as inoculum. The particles were removed by sedimentation.

Duration of test (contact time):

28 d

Initial test substance concentration

Initial conc.:

2 mg/L

Based on:

test mat.

Parameter followed for biodegradation estimation

Parameter followed for biodegradation estimation:

O2 consumption

Details on study design:

Test bottles
The test was performed in 0.30 L BOD (biological oxygen demand) bottles with glass stoppers

Nutrients and stock solutions
The river water used in the Closed Bottle test was spiked per liter of water with 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.

Test procedures
Sodium acetate and the test substance were added to the bottles using stock solutions of 1.0 g/L.
The Closed Bottle test was performed according to the study plan. The study plan was developed from ISO Test Guidelines (1994).
Use was made of 10 bottles containing only river water (inoculum and medium), 10 bottles containing river water
and silica gel (2 g/bottle), 10 bottles containing river water, silica gel and test substance, and 6 bottles containing sodium acetate and river water.
The concentrations of the test substance and sodium acetate in the bottles were 2.0 and 6.7 mg/L, respectively.
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.

CALCULATIONS:
The calculated theoretical oxygen demand (ThOD) of coco dipropylene triamine is 2.8 mg/mg.
The ThOD of sodium acetate is 0.8 mg/mg

Calculation of the biochemical oxygen demand (BOD) Provided that the oxygen concentrations in all bottles at the start of the test were
equal, the amounts of oxygen consumed in test and reference compound bottles were calculated as follows:
Oxygen consumptionn (mg/L) by test substance = Mcs - Mt
Oxygen consumptionn (mg/L) by reference compound = Mc - Ma

Mc or cs is the mean oxygen level in the control bottles filled with river water spiked with mineral salts with (cs) and without silica gel (c) n days after
the start of the test. Mt or a is the mean oxygen concentration in the bottles containing the test substance (t) or the reference compound, sodium acetate (a), present in river water spiked with mineral salts n-days after the start of the test.
The biological oxygen demand (BOD) mg/mg of the test compound and sodium acetate was calculated by dividing the oxygen consumption by the
concentration of the test substance and sodium acetate in the closed bottle, respectively.

Calculation of the biodegradation percentages
The biodegradation was calculated as the ratio of the biochemical oxygen demand (BOD) to the theoretical oxygen demand (ThOD)

Reference substance

Reference substance:

acetic acid, sodium salt

Results and discussion

% Degradation

Parameter:

% degradation (O2 consumption)

Value:

75

Sampling time:

28 d

Remarks on result:

other: in the presence of silica gel

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 coco dipropylene triamine to microorganisms degrading acetate is not relevant.
Inhibition of the endogenous respiration of the inoculum by the test substance tested in the presence of silicagel 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 7.9 at the start of the test. The pH of the medium at day 28 was 7.9. (control) and 7.8 (control with silica gel and test).
Temperatures were within the prescribed temperature range of 22 to 24°C.

Applicant's summary and conclusion

Validity criteria fulfilled:

yes

Remarks:

endogenous respiration of 1.0 mg/L at day 28; differences between replicates at day 28 <20%; biodegradation percentage of reference substance at day 14 was 76 ; oxygen concentrations >0.5 mg/l in the bottles during the test period

Interpretation of results:

readily biodegradable

Conclusions:

Coco dipropylene triamine is biodegraded 75% at day 28 in the Closed Bottle test. Over 60% biodegradation was not achieved within a
period of 10 days (14 days for the Closed Bottle test) immediately following the attainment of 10% biodegradation.
However, coco dipropylene triamine is a chemical consisting of a hydrophilic group is linked to a hydrophobic moiety.
Biodegradation of both moieties of surfactants requires the concerted action of at least two microorganisms as a single organism usually lacks the
full complement of enzymatic capabilities (van Ginkel, 1996). In ready biodegradability tests, the two moieties of this fatty amine derivative are
therefore degraded sequentially. The degradation curve will therefore be the sum of two growth curves. The biodegradation of the two moieties may be fully in line with the time-day window criterion when judged as separate chemicals. The time window criterion was developed on the assumption
that a compound is degraded according to the “standard” growth curve in ready biodegradability tests. The time-window should be ignored as a pass fail criterion for this surfactant. Coco dipropylene triamine is classified as readily biodegradable based on the achievement of 75% biodegradation at day 28.
Test performed under GLP according guidelines (with only minor acceptable deviations) meeting all the validity criteria.

Executive summary:

In order to assess the biotic degradation, a ready biodegradability test was performed which allows the biodegradability to be measured in an aerobic aqueous medium. The ready biodegradability was determined in the Closed Bottle test performed according to slightly modified OECD, EU and ISO Test Guidelines, and in compliance with the OECD principles of Good Laboratory Practice. Coco dipropylene triamine in the presence of silica gel added did not cause a reduction in the endogenous respiration. The test substance is therefore considered to be non-inhibitory to the inoculum. Coco dipropylene triamine was biodegraded 75% at day 28 in the Closed Bottle test. Hence this compound should be classified as readily biodegradable. The test is valid as shown by an endogenous respiration of 1.0 mg/L and by the total mineralization of the reference compound, sodium acetate. Sodium acetate was degraded 76% of its theoretical oxygen demand after 14 days. Finally, the most important criterion was met by oxygen concentrations >0.5 mg/L in all bottles during the test period.