Amines, N-C12-18-alkyltrimethylenedi-, reaction products with chloroacetic acid, sodium salts

Biodegradation in water: screening tests

Link to relevant study record(s)

Reference

Endpoint:

biodegradation in water: ready biodegradability

Type of information:

experimental study

Remarks:

test performed accoring OECD 301D guidelines

Adequacy of study:

key study

Study period:

19-02-2019 - 14-05-2019

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:

only minor devation

Principles of method if other than guideline:

Minor deviations from the guidelines of the Closed Bottle test (OECD TG 301D) 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) river water instead of an effluent/extract/mixture was used as inoculum.

GLP compliance:

yes (incl. QA statement)

Specific details on test material used for the study:

Chemical name Sodium cocopropylenediamine glycinate
Substance name: Amines, N-C12-18-alkyltrimethylenedi-, reaction products with chloroacetic acid, sodium salts
Old CAS no 97659-51-3
New CAS no: 2098351-38-1

Oxygen conditions:

aerobic

Inoculum or test system:

natural water: freshwater

Details on inoculum:

River water was sampled from the Rhine near Heveadorp, The Netherlands (14-02-2019). The nearest plant (Arnhem-Zuid) treating domestic wastewater biologically was 3 km upstream. 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 after 1 day while moderately aerating.

Duration of test (contact time):

28 d

Initial conc.:

1.5 mg/L

Based on:

act. ingr.

Initial conc.:

5 mg/L

Based on:

test mat.

Parameter followed for biodegradation estimation:

O2 consumption

Details on study design:

Test procedures
The Closed Bottle test (OECD TG 301D) 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, 6 bottles containing river water and sodium acetate, 10 bottles containing river water with test substance. The concentrations of the test substance, and sodium acetate in the bottles were 5 mg/L (1.5 mg/L active) 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 com¬pletely 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.

Reference substance:

acetic acid, sodium salt

Remarks:

SIGMA ALDRICH Batch no. BCBP8197V

Key result

Parameter:

% degradation (O2 consumption)

Value:

64

Sampling time:

28 d

Parameter:

% degradation (O2 consumption)

Value:

81

Sampling time:

60 d

Remarks on result:

other: Readily biodegradable

Details on results:

Sodium cocopropylenediamine glycinate was biodegraded by 64% at day 28 and reached 81% at day 60 in the prolonged Closed Bottle test (Table II, Figure). 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, sodium cocopropylenediamine glycinate is a chemical consisting of a hydrophilic group 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 surfactant 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 passfail criterion for this surfactant. Sodium cocopropylenediamine glycinate is classified as readily biodegradable based on the achievement of 64% biodegradation at day 28.

Results with reference substance:

The biodegradation percentage of the reference compound, sodium acetate, at day 14 was 90

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 the test substances to microorganisms degrading acetate is not relevant. Inhibition of the endogenous respiration of the inoculum by the test substance at day 7 was not detected (Table I). Therefore, no inhibition of the biodegradation due to the "high" initial test substance concentration is expected.

 

Test conditions

The pH of the media was 8.8 (control and reference compound) and 8.9 (test)at the start of the test. The pH of the medium at day 28 was 8.8 (test) and 8.9 (control). At day 60 the pH of the control and test was 8.8 and 8.6, respectively. The temperature ranged from 22.5 to 22.8°C which is within the prescribed temperature range of 22 to 24°C.

Validity of the test

The validity of the test is demonstrated by an endogenous respiration of 1.2 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 90 (Table II and Figure). Finally, the validity of the test is shown by oxygen concentrations >0.5 mg/L in all bottles during the test period.

Validity criteria fulfilled:

yes

Remarks:

The test is valid because of an endogenous respiration of 1.2 mg/L at day 28. Less than 20% difference of replicates day 28. The biodegradation% the reference compound at day 14 was 90. Final oxygen concentrations were >0.5 mg/L.

Interpretation of results:

readily biodegradable

Conclusions:

Test performed according guidelines meeting specific criteria. Test performed under GLP and results well documented.

Executive summary:

To assess the biotic degradation of sodium cocopropylenediamine glycinate, 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.

The test substance did not cause a reduction in the endogenous respiration at day 7. The test substance is therefore considered to be non-inhibitory to the inoculum. The test substance was biodegraded by 64% at day 28 in the OECD 301D Closed Bottle test and should therefore be classified as readily biodegradable. The biodegradation percentage increased further in the prolonged Closed Bottle test and reached 81% at day 60.

The test is valid as shown by an endogenous respiration of 1.2 mg/L and by the total mineralization of the reference compound, sodium acetate. Sodium acetate was degraded by 90% 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.

Description of key information

To assess the biotic degradation of sodium cocopropylenediamine glycinate, 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.

The test substance did not cause a reduction in the endogenous respiration at day 7. The test substance is therefore considered to be non-inhibitory to the inoculum. The test substance was biodegraded by 64% at day 28 in the OECD 301D Closed Bottle test and should therefore be classified as readily biodegradable. The biodegradation percentage increased further in the prolonged Closed Bottle test and reached 81% at day 60.

Key value for chemical safety assessment

Biodegradation in water:

readily biodegradable

Type of water:

freshwater

Additional information

To assess the biotic degradation of sodium cocopropylenediamine glycinate, 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.

The test substance did not cause a reduction in the endogenous respiration at day 7. The test substance is therefore considered to be non-inhibitory to the inoculum. The test substance was biodegraded by 64% at day 28 in the OECD 301D Closed Bottle test and should therefore be classified as readily biodegradable. The biodegradation percentage increased further in the prolonged Closed Bottle test and reached 81% at day 60.