Reaction mass of sodium hydrogen N,N-dibutyl-10-(sulphonatooxy)octadecanamidate and sodium sulphooctadecanoate

Biodegradation in water: screening tests

Link to relevant study record(s)

Reference

Reference 1

Endpoint:

biodegradation in water: ready biodegradability

Type of information:

experimental study

Adequacy of study:

key study

Study period:

2006-01-12 to 2006-02-10

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

OECD Guideline 310 (Ready Biodegradability - CO2 in Sealed Vessels (Headspace Test)

Version / remarks:

Draft October 2003

Deviations:

no

Qualifier:

according to guideline

Guideline:

ISO 14593:1999 (Water quality - Evaluation of ultimate aerobic biodegradability of organic compounds in aqueous medium - Method by analysis of inorganic carbon in sealed vessels (CO2 headspace test))

Version / remarks:

1999

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Oxygen conditions:

aerobic

Inoculum or test system:

activated sludge, domestic, non-adapted

Details on inoculum:

- Source of inoculum/activated sludge: Municipal sewage treatment plant, Hildesheim Germany

Conditioning: The activated sludge was washed twice with autoclaved tap water and maintained in an aerobic condition by aeration for 4 hours, and then it was homogenized with a mixer. Thereafter the sludge was filtered through folded filter and aerated with CO2-free air for 6 days. 50 mL/L were used to initiate inoculation.

Duration of test (contact time):

28 d

Initial conc.:

50 mg/L

Based on:

ThCO2

Parameter followed for biodegradation estimation:

CO2 evolution

Details on study design:

TEST CONDITIONS
- Composition of medium: Mineral nutrient solution acc. to OECD 310 / 80 mL
- Additional substrate: no
- Test temperature: 20 - 25 °C (constant at + 1 °C)
- Aeration of dilution water: yes
- Continuous darkness: yes

TEST SYSTEM
- Culturing apparatus: Headspace flasks / 120 mL
- Number of culture flasks/concentration: 3
- Measuring equipment: TOC-analyser: Multi N/C 3000, Analytik Jena, Thermo-hygrograph, Lufft, Gas tight syringe, 1 mL, SGE; Shaker, Bühler; Shaker, Heidolph

SAMPLING
- Sampling frequency: Determination of CO2 was carried out by lC analysis with a carbon analyser according to DIN EN 1484 on days 0, 1, 4, 7, 11, 14, 21 and 28.

CONTROL AND BLANK SYSTEM
- Inoculum blank: inoculum and test medium
- Functional control: reference item, inoculum and test medium
- Inhibition control: test item, reference item, inoculum and test medium

Reference substance:

benzoic acid, sodium salt

Key result

Parameter:

% degradation (CO2 evolution)

Value:

73

Sampling time:

28 d

Details on results:

Under the test conditions, the percentage biodegradation of the test item reached a maximum of 73 % after 28 days of incubation. ln the inhibition control containing both test and reference item a biodegradation rate of 68 % occurred within 14 days and came to a maximum of 77 % after 28 days.

Results with reference substance:

The biodegradation of the reference item was not inhibited by the test item in the inhibition control. The 10 % level (beginning of biodegradation) was reached after 1 day. The pass level of 60 % was reached after 24 days.

Table 1: Biodegradation and Confidence interval of the Test item in comparison to the Functional Control

Day (d)	Biodegradation [%]				Confidence interval on day 28 P = 95 %
	7	14	21	28
Test item 50 mg/L	22	42	50	73	47 - 95
Functional control 25 mg/L	68	79	83	86	85 - 87
Inhibition control 50 mg/L + 25 mg/L	51	68	70	77	73 - 81

Validity criteria fulfilled:

yes

Interpretation of results:

readily biodegradable

Conclusions:

The test item is biodegradable after 28 days and complies with the biodegradability criteria as laid down in Annex III of Regulation (EC) No 648/2004 on detergents.

Executive summary:

The test item was tested for its ready biodegradability with a non-adapted activated sludge over a test period of 28 days in the Headspace Test. The study was conducted according to OECD 310 and EN ISO 14593. The test item was tested with a concentration of 50 mg/L in triplicates, corresponding to carbon content (TOC) of 10.3 mg C/L in the test vessels. The biodegradation of the test item was followed by TIC analyses of the quantity of CO2 produced by the respiration of bacteria. The amount of TIC produced was calculated by correcting the results of the test and reference item for endogenous TIC production of the control groups. The biodegradation was calculated. To check the activity of the test system sodium benzoate was used as functional control. The percentage degradation of the functional control reached the pass level of 60 % after 3 days and came to 86 % after 28 days. ln the inhibition control containing both test and reference item a biodegradation rate of 68 % occurred within 14 days and came to a maximum of 77 % after 28 days. The biodegradation of the reference item was not inhibited by the test item in the inhibition control. The 10 % level (beginning of biodegradation) was reached after 1 day. The pass level of 60 % was reached after 24 days. The biodegradation came to a maximum of 73 % after 28 days. The validity criteria according to the guideline are fulfilled. In conclusion, the test item is regarded as readily biodegradable.

Reference 2

Endpoint:

biodegradation in water: ready biodegradability

Type of information:

experimental study

Adequacy of study:

supporting study

Study period:

1995-04-12 to 1995-05-16

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

guideline study with acceptable restrictions

Qualifier:

according to guideline

Guideline:

OECD Guideline 301 A (Ready Biodegradability: DOC Die Away Test)

Deviations:

no

Qualifier:

according to guideline

Guideline:

EU Method C.4-A (Determination of the "Ready" Biodegradability - Dissolved Organic Carbon (DOC) Die-Away Test)

Deviations:

no

GLP compliance:

not specified

Oxygen conditions:

aerobic

Inoculum or test system:

activated sludge, domestic, non-adapted

Duration of test (contact time):

34 d

Initial conc.:

200 mg/L

Based on:

test mat.

Parameter followed for biodegradation estimation:

DOC removal

Reference substance:

acetic acid, sodium salt

Key result

Parameter:

% degradation (DOC removal)

Value:

63

Sampling time:

34 d

Results with reference substance:

90 % degradation after 5 days

Validity criteria fulfilled:

yes

Interpretation of results:

other: 63 % removal but pass level of 70 % not reached

Conclusions:

At the end of the 28-d-period the value of percentage biodegradation was 63 % removal. The test was prolonged for 6 days. During this period no additional degradation occured. The pass level for ready biodegradation (70 %) was not reached within the 34-d-period.

Executive summary:

The ready biodegradation in an aerobic aqueous medium of the test item was tested by the DOC Die-Away-Test according to OECD TG 301 A and EU method C.4-A. Mineral medium containing a known concentration of the test substance was inoculated with micro - organisms from the effluent of a treatment plant (domestic sewage), filled in vessels and incubated in the dark at 22 +/- 2°C, over 34 days period. Degradation was followed by DOC (Dissolved organic carbon) analysis twice a week. The Biodegradation was calculated by expressing the DOC removed as a percentage of the concentration initially present. At the end of the 28-d-period the value of percentage biodegradation was 63 % removal. The test was prolonged for 6 days. During this period no additional degradation occured. The pass level for ready biodegradation (70 %) was not reached within the 34-d-period.

Description of key information

In one key study, the test item is readily biodegradable in a test according to OECD 310, the biodegradation came to a maximum of 73 % after 28 days .The 95 % confidence interval on day 28 was 47 - 95 %. The validity criteria according to the guideline are fulfilled. In a supporting study according 301 A a DOC removal of 63 % was shown.

Key value for chemical safety assessment

Biodegradation in water:

readily biodegradable

Type of water:

freshwater

Additional information

The test item was tested for its ready biodegradability with a non-adapted activated sludge over a test period of 28 days in the Headspace Test. The study was conducted according to OECD 310 and EN ISO 14593. The test item was tested with a concentration of 50 mg/L in triplicates, corresponding to carbon content (TOC) of 10.3 mg C/L in the test vessels. The biodegradation of the test item was followed by TIC analyses of the quantity of CO2 produced by the respiration of bacteria. The amount of TIC produced was calculated by correcting the results of the test and reference item for endogenous TIC production of the control groups. The biodegradation was calculated. To check the activity of the test system sodium benzoate was used as functional control. The percentage degradation of the functional control reached the pass level of 60 % after 3 days and came to 86 % after 28 days. ln the inhibition control containing both test and reference item a biodegradation rate of 68 % occurred within 14 days and came to a maximum of 77 % after 28 days. The biodegradation of the reference item was not inhibited by the test item in the inhibition control. The 10 % level (beginning of biodegradation) was reached after 1 day. The pass level of 60 % was reached after 24 days. The biodegradation came to a maximum of 73 % after 28 days. The validity criteria according to the guideline are fulfilled. In conclusion, the test item is regarded as readily biodegradable.