Bis[2-(diethylamino)ethyl] adipate

Biodegradation in water: screening tests

Administrative data

Endpoint:

biodegradation in water: ready biodegradability

Type of information:

experimental study

Adequacy of study:

key study

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2018

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

OECD Guideline 301 B (Ready Biodegradability: CO2 Evolution Test)

Deviations:

yes

Remarks:

Temperature range was 19.5 – 21.2 °C instead of 20.0 – 24.0 °C. As degradation of the positive control was in the normal range, this is considered as uncritical concerning the outcome of the study

GLP compliance:

yes (incl. QA statement)

Test material

Test material information

Constituent 1

Reference substance name:

Bis[2-(diethylamino)ethyl] adipate

EC Number:

240-610-6

EC Name:

Bis[2-(diethylamino)ethyl] adipate

Cas Number:

16545-00-9

Molecular formula:

C18H36N2O4

IUPAC Name:

1,6-bis[2-(diethylamino)ethyl] hexanedioate

impurity 1

Reference substance name:

2-diethylaminoethanol

EC Number:

202-845-2

EC Name:

2-diethylaminoethanol

Cas Number:

100-37-8

Molecular formula:

C6H15NO

IUPAC Name:

2-(diethylamino)ethanol

Test material form:

liquid

Study design

Oxygen conditions:

aerobic

Inoculum or test system:

activated sludge, domestic (adaptation not specified)

Details on inoculum:

6.3 Test System
6.3.1 Specification
Activated sludge from a biologic sewage treatment plant was used as inoculum. The chosen plant treats mostly domestic sewage.
6.3.2 Source and Pre-Treatment of inoculum
6.3.2.1 Source
The sludge was taken from the activation basin of the ESN (Stadtentsorgung Neustadt) sewage treatment plant, Im Altenschemel, NW-Lachen-Speyerdorf.
Date of collection: 12. Jan. 2018, batch no: 20180112.

Duration of test (contact time):

28 d

Initial test substance concentration

Initial conc.:

32.3 mg/L

Based on:

test mat.

Results and discussion

% Degradation

% Degradation 1

Key result

Parameter:

% degradation (CO2 evolution)

Value:

106

Sampling time:

28 d

% Degradation 2

Key result

Parameter:

% degradation (CO2 evolution)

Value:

38

Sampling time:

14 d

Any other information on results incl. tables

1         

1.1         Bis[2-(diethylamino)ethyl]adipate

¨             Bis[2-(diethylamino)ethyl]adipateis considered as “ultimately biodegradable“.

¨             

¨             

¨             

¨             

1.2         

All validity parameters and values are presented in the following table:

Table9.2‑a          Validity

Parameter	Criterion	Found	Assessment
IC content of test item solution in medium	5% of TC	0 %	valid
CO2emitted by the controls	< 70 mg/L	8.9 mg/L	valid
Difference within replicates	20%	3.5 %	valid
Degradation of positive control > 60%	≤14 days	9 days	valid
Degradation in the toxicity flask on day 14	> 25%	68.5 %	non-toxic

Applicant's summary and conclusion

Validity criteria fulfilled:

yes

Interpretation of results:

other: ultimately biodegradable

Conclusions:

All validity criteria were met. Degradation behaviour of positive control and toxicity control was normal. Abiotic degradation was not observed. Both replicates of the test item showed very good correspondence. Degradation values of more than 100 % were calculated. This is due to the fact that the measurement errors of test flasks and control flasks add up when using the equation proposed in the OECD 301B guideline. If degradation in the toxicity flask is below 25 % after 14 days, the test item can be considered as toxic towards the inoculum. As degradation in the toxicity flask was 68.5 % after 14 days, the test item can be stated as “not toxic towards the inoculum in a concentration of 32.9 mg/L”. Ready degradability is defined in the guidelines as degradation surpassing 60% within 10 days after reaching a level of 10 %. Therefore, the test item Bis[2-(diethylamino)ethyl]-adipate can be considered as “not readily biodegradable”. Degradation surpassed 60% within 28 days, though. Therefore, the test item can be considered as “ultimately biodegradable within 28 days. No observations were made which might cause doubts concerning the validity of the study outcome. The result of the test can be considered valid.

Executive summary:

The test item Bis[2-(diethylamino)ethyl]adipate was tested using a concentration of nominally 20 mg organic carbon/L (corresponding to 31.9 mg Bis[2-(diethylamino)ethyl]-adipate/L) in test medium following OECD 301B and EU-Method C.4-C. Aniline was chosen as positive control. Activated sludge was used as inoculum (concentration in the test 25.0 mg dry matter/L). The test was left running for 28 days.

All validity criteria were met. Degradation of the positive control was 80 % after 9 days. The following data were determined for the test itemBis[2-(diethylamino)ethyl]adipate:

10-day-window:                                                                                                                                                                 day 4 – 14
degradation at the end of 10-day-window                                                                                                                         38 %
degradation at the end of the test                                                                                                                                     106 %
pass level following guideline:                                           60 % at the end of 10-day-window for pure substances

                                                                                                                 respective 60 % at the end of the test for mixtures

 

Therefore, when applying the 10-day-window, the test itemBis[2-(diethylamino)ethyl]-adipateis not readily biodegradable following OECD 301B and EU C.4-C respectively. As degradation surpassed 60 % in the course of the test, Bis[2-(diethylamino)ethyl]adipate is considered as ultimately biodegradable within 28 days.