Fatty acids, C16-18, reaction products with triethanolamine, di-Me sulfate-quaternized

Biodegradation in water: screening tests

Link to relevant study record(s)

Reference

Endpoint:

biodegradation in water: ready biodegradability

Type of information:

experimental study

Adequacy of study:

key study

Study period:

07.02.2002 to 06.03.2002

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

guideline study with acceptable restrictions

Remarks:

Guideline study that did not have an abiotic sterile control and not all details were reported.

Qualifier:

according to guideline

Guideline:

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

Version / remarks:

adopted 1992

Deviations:

yes

Remarks:

An abiotic sterile control was not included in the test.

GLP compliance:

yes

Oxygen conditions:

aerobic

Inoculum or test system:

activated sludge (adaptation not specified)

Details on inoculum:

- Source of inoculum/activated sludge (e.g. location, sampling depth, contamination history, procedure): Activated sludge was collected from the sewage treatment plant Frankfurt-Niederrad (Germany)
- Preparation of inoculum for exposure: Activated sludge was centrifuged (250 mg/L). The activated sludge was aerated for 1 d and washed three times with mineral medium.
- Pretreatment: no
- Concentration of sludge: 250 mg/L

Duration of test (contact time):

28 d

Initial conc.:

20.8 mg/L

Based on:

test mat.

Initial conc.:

21.3 mg/L

Based on:

test mat.

Parameter followed for biodegradation estimation:

CO2 evolution

Details on study design:

TEST CONDITIONS
- Composition of medium: mineral medium according to OECD Guideline 301 B
- Additional substrate: no
- Solubilising agent (type and concentration if used): no
- Test temperature: 22 +/- 2°C
- pH: not reported
- pH adjusted: not reported
- Aeration of dilution water: not reported
- Suspended solids concentration: not reported
- Continuous darkness: testing was conducted in brown glass bottles in diffuse light

TEST SYSTEM
- Culturing apparatus: 5-L brown glass bottles
- Number of culture flasks/concentration: 1 (two concentrations tested: 20.8 and 21.3 mg/L)
- Method used to create aerobic conditions: activated sludge was aerated for one d
- Measuring equipment: no details reported
- Test performed in closed vessels: yes
- Details of trap for CO2 and volatile organics if used: barium hydroxide was used for CO2 trapping (not further specified)

SAMPLING
- Sampling frequency: CO2 measurements were performed on day 1, 2, 5, 9, 12, 16, 21, and 28

CONTROL AND BLANK SYSTEM
- Inoculum blank: performed
- Abiotic sterile control: not performed
- Toxicity control: performed
- Other: functional/procedural control (reference substance) performed

Reference substance:

benzoic acid, sodium salt

Remarks:

(21.5 mg/L)

Parameter:

% degradation (CO2 evolution)

Value:

> 10

Sampling time:

6 d

Parameter:

% degradation (CO2 evolution)

Value:

> 60

Sampling time:

21 d

Parameter:

% degradation (CO2 evolution)

Value:

65 - 66

Sampling time:

28 d

Remarks on result:

other: readily biodegradable

Results with reference substance:

The reference substance sodium benzoate was biodegraded by 71% after 12 d and thus fulfilling the guideline requirement of >60% biodegradation after 14 d.

The test substance proved to be readily biodegradable (65 -66% after 28 d; according to the revised OECD Guidelines the 10-d window should not be applied to interpret the results of a test with a mixture of structurally similar chemicals) in a study conducted according OECD Guideline 301 B (Ready Biodegradability: CO2 Evolution Test; adopted 1992). The reference substance sodium benzoate was biodegraded by 71% after 12 d and thus fulfilling the guideline requirement of >60% biodegradation after 14 d. In the toxicity control (20.8 mg/L sodium benzoate and 20.9 mg/L test substance) a biodegradation of 53% after 12 d was observed and thus fulfilling the requirements of the guideline to be not inhibitory to the microorganisms (>25% after 14 d). The CO2 evolution in the inoculum blank was <=40 mg/L in 28 d. The difference of extremes of replicate values of the removal of the test substance at the plateau and at the end of the test was less than 20%.

Validity criteria fulfilled:

yes

Interpretation of results:

readily biodegradable

Conclusions:

The test substance proved to be readily biodegradable (65 -66% after 28 d; according to the revised OECD Guidelines the 10-d window should not be applied to interpret the results of a test with a mixture of structurally similar chemicals) in a study conducted according OECD Guideline 301 B (Ready Biodegradability: CO2 Evolution Test; adopted 1992).

Executive summary:

The ready biodegradation of the test substance fully saturated TEA-Esterquat, hardened was investigated in a study conducted according to OECD Guideline 301B (Ready Biodegradability: CO2 Evolution Test; adopted 1992) over a period of 28 days and using activated sludge municipal sewage treatment plant as inoculum. The biodegradation rate was determined by measurement of CO2 evolution. Inoculum blank, procedural/functional control with the reference substance sodium and toxicity control using 20.8 mg/L sodium benzoate and 20.9 mg/L test substance were performed. This study is regarded as reliable with restriction and satisfies the guideline requirements for ready biodegradation. The test substance proved to be readily biodegradable (65 -66% after 28 d; according to the revised OECD Guidelines the 10-d window should not be applied to interpret the results of a test with a mixture of structurally similar chemicals) in a study conducted according OECD Guideline 301 B (Ready Biodegradability: CO2 Evolution Test; adopted 1992).

Description of key information

Fully saturated TEA-Esterquat is readily biodegradable.

Key value for chemical safety assessment

Biodegradation in water:

readily biodegradable

Type of water:

freshwater

Additional information

Fully saturated TEA-Esterquat proved to be readily biodegradable (65-66 % after 28 d).TEA-Esterquats are - as UVBC substances - mixtures of structurally similar chemicals. To interpret the results of a test with a mixture of structurally similar chemicals in a study conducted according to OECD Guideline 301 B (Ready Biodegradability: CO2 Evolution Test; 1992), the 10 d criterion should not be applied.

These results are in line with the studies conducted with the structurally related source substances partially unsaturated TEA-Esterquat and oleic acid-based TEA-Esterquat.

The ready biodegradability of partially unsaturated TEA-Esterquat was investigated in a study conducted according to OECD Guideline 301 B (Ready Biodegradability: CO2 Evolution Test). The test item proved to be readily biodegradable (78.8 % biodegradation after 7 d; 98.9 % biodegradation after 28 d) at an initial test item concentration of 55 mg test mat./L (20 mg TOC/L). Sampling was performed on day 0 and after 4, 7, 11, 14, 21, and 28 days. The 10 d  window criterion was passed, although this criterion should not be applied to TEA-Esterquats.

A further test according to OECD Guideline 301 B (Ready Biodegradability: CO2 Evolution Test) with partially unsaturated TEA-Esterquat resulted in 78 % degradation after 28 days, fulfilling the 10 d criterion at a test item concentration of 17.1 mg test mat./L (10 mg C/L).

Partially unsaturated TEA-Esterquat proved to be readily biodegradable in further studies according to OECD Guideline 301 B (Ready Biodegradability: CO2 Evolution Test). Biodegradation from 75 % to 67.2% was observed.

The ready biodegradation of partially unsaturated TEA-Esterquat was also investigated according to OECD Guideline 301 D and EU-Method C.4 -E over a period of 28 days and using domestic sewage as inoculum. The biodegradation rate was determined by measurement of oxygen consumption. The test item proved to be readily biodegradable and fulfilling the 14-d window criterion. The functional control reached the pass level >60% after 14 d. In the toxicity control containing both test and reference item >25% biodegradation based on oxygen consumption occurred within 14 d thus indicating that the test item was not inhibitory at the concentration tested.

Several further studies were performed according to OECD Guideline 301D. Biodegradation was between 74 and 99% (O₂ consumption).

Two studies according to OECD Guideline 301 C (Ready Biodegradability: Modified MITI Test (I)) are available for partially unsaturated TEA-Esterquat as well as one study according to OECD Guideline 301 F (Ready Biodegradability: Manometric Respirometry Test) showed ready biodegradability. Biodegradation was 67% - 78% O₂consumption for the MITI (I) tests and 79 % O₂consumption for the Manometric respirometry test.

TEA-Esterquat fully saturated proved to be readily biodegradable (65-66 % after 28 d).TEA-Esterquats are - as UVBC substances - mixtures of structurally similar chemicals. To interpret the results of a test with a mixture of structurally similar chemicals in a study conducted according to OECD Guideline 301 B (Ready Biodegradability: CO2 Evolution Test; 1992) the 10 d criterion should not be applied.

The arithmetic mean biodegradability resulting from the % biodegradation of these most reliable studies is 80.2% in 28 days. Further reliable studies on readily biodegradability available The arithmetic mean of the biodegradation of all reliable studies is 78.4 % in 28 days. There is strong evidence, that oleic acid-based TEA-Esterquat is readily biodegradable.

 

Anaerobic biodegradation

Under anaerobic conditions partially unsaturated TEA-Esterquat was biodegraded in a test according to ECETOC Anaerobic Biodegradation (Technical Report No. 28) with activated sludge from a sewage treatment plant as inoculum. The test material attained 76% degradation after 56 days and therefore can be considered as biodegradable under anaerobic conditions.