1,1,3,3-tetramethylbutylamine

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:

other: GLP guideline study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

1998

Report date:

1999

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

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

GLP compliance:

yes

Test material

Test material information

Constituent 1

Reference substance name:

1,1,3,3-tetramethylbutylamine

EC Number:

203-491-1

EC Name:

1,1,3,3-tetramethylbutylamine

Cas Number:

107-45-9

Molecular formula:

C8H19N

IUPAC Name:

2,4,4-trimethylpentan-2-amine

Study design

Oxygen conditions:

aerobic

Inoculum or test system:

activated sludge, domestic (adaptation not specified)

Details on inoculum:

- Source of inoculum/activated sludge: secondary effluent from municipal treatment plant handling domestic sewage
- Preparation of inoculum for exposure: inoculum was aerated by means of a magnetic stirrer
- Concentration of sludge: 5 mL inoculum per 1 L test solution
- Water filtered: yes
- Type and size of filter used, if any: coarse paper filter (folded filter)

Duration of test (contact time):

28 d

Initial test substance concentration

Initial conc.:

2.05 mg/L

Based on:

test mat.

Parameter followed for biodegradation estimation

Parameter followed for biodegradation estimation:

O2 consumption

Details on study design:

TEST CONDITIONS
- Composition of medium: mineral medium according to OECD 301
- Test temperature: 22 +/- 2°C
- pH: 7.4 +/- 0.2
- pH adjusted: yes
- Continuous darkness: yes

TEST SYSTEM
- Culturing apparatus: temperature controlled incubator
- Number of culture flasks/concentration: 3
- Method used to create aerobic conditions: pre-aeration of mineral nutrient solution
- Measuring equipment: Oximeter with oximatic electrode

SAMPLING
- Sampling frequency: days 0, 7, 14, 21, 28
- Sampling method: each sample was discarded following sampling

CONTROL AND BLANK SYSTEM
- Inoculum blank: yes
- Toxicity control: yes, 50% test substance, 50% reference substance

Reference substance

Reference substance:

benzoic acid, sodium salt

Results and discussion

Test performance:

The maximum oxygen depletion within the inoculum blank was 0.54 mg/L and after 28 days the residual concentration of oxygen in all bottles was > 0.5 mg/L.
The toxicity control showed a degradation rate of 40% indicating no cytotoxicity from the test substance to the inoculum used. Thus, the valididy criteria given in the OECD test guideline are met and the study is considered valid.

% Degradation

Parameter:

% degradation (O2 consumption)

Value:

< 10

Sampling time:

28 d

Details on results:

The toxicity control showed a degradation rate of 40% indicating no toxicity of the test substance to the inocculum.

Kinetic of test substance (in %):
0 after 7 day(s)
0 after 14 day(s)
2 after 21 day(s)
1 after 28 day(s)

BOD5 / COD results

Results with reference substance:

The reference substance sodium benzoate was degraded by 87% within 28 days; the criteria for "ready degradability" of equal or more than 60% was met within 7 days.

Applicant's summary and conclusion

Validity criteria fulfilled:

yes

Remarks:

according to OECD 301 D

Interpretation of results:

under test conditions no biodegradation observed

Conclusions:

Under the conditions of this study on ready biodegradability the test substance was not biodegradable. The study is considered valid.