bis(hydrogenated tallow C16-18-alkyl)hydroxylamine

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:

1995-06-14 to 1995-09-07

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: GLP and guideline study

Qualifier:

according to guideline

Guideline:

EU Method C.4-C (Determination of the "Ready" Biodegradability - Carbon Dioxide Evolution Test)

Version / remarks:

92/69/EEC

Deviations:

no

Qualifier:

according to guideline

Guideline:

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

Version / remarks:

adopted July 17, 1992

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: 'Waterschap de Dommel', 's-Hertogenbosch, the Netherlands
- Storage conditions: The sludge was kept under continuous aeration until further treatment. The concentration of suspended solids was 2.9 g/L in the concentrated sludge. Before use, the sludge was allowed to settle for at least 30 minutes and the liquid decanted for use as inoculum at the amount of 10 mL/L of mineral medium.
- Concentration of sludge: 10 mL/L of mineral medium
- Water filtered: yes
- Type of filter used: Tap-water purified by reverse osmosis and subsequently passed over activated carbon and ion-exchange cartridges (Millipore Corp., Bedford, Mass., USA).

Duration of test (contact time):

28 d

Initial conc.:

37 - 37.2 mg/L

Based on:

test mat.

Initial conc.:

15 mg/L

Based on:

other: TOC

Parameter followed for biodegradation estimation:

CO2 evolution

Details on study design:

TEST CONDITIONS
- Composition of medium: according to OECD and EU guideline
- Test temperature: 20-23°C
- pH: 7.6-7.7
- pH adjusted: no
- Aeration of dilution water: yes
- Suspended solids concentration: 2.9 g/L
- Continuous darkness: test done in brown coloured bottles

TEST SYSTEM
- Culturing apparatus: 2 litre all-glass brown coloured bottles
- Number of culture flasks/concentration: 2
- Method used to create aerobic conditions: Bubbling CO2-free air through the solution at a rate of approximately 1-2 bubbles per second (ca. 30-100 mL/min).
- Measuring equipment: Titration
- Details of trap for CO2 and volatile organics if used: Three CO2-absbrbers (bottles filled with 100 mL 0.0125 H Ba(OH)2) were connected in series to the exit air line of each test bottle.

SAMPLING
- Sampling frequency: every second or third day during the first 10 days, and thereafter at least every fifth day until the 28th day
- Sampling method: Each time the CO2-absorber nearest to the test bottle was removed for titration; each of the remaining two absorbers was moved one position in the direction of the test bottle. A new CO2-absorber was placed at the far end of the series. Phenolphthalein was used as pH-indicator.

CONTROL AND BLANK SYSTEM
- Inoculum blank: containing only inoculum (2 bottles)
- Toxicity control: yes
- Positive control: containing reference substance (ca. 40 mg/L sodium acetate (Merck art. 6268, batch 049 TA933768), TOC= 12 mg/L) and inoculum (1 bottle).

STATISTICAL METHODS:
Calculations were based on the actual normality without rounding off. Relative degradation values was calculated from the cumulative CO2 production relative to the total expected CO2 production based on the total carbon content of the amount of test material present in the test bottles. They were plotted versus time together with the relative degradation of the positive control.

Reference substance:

other: sodium acetate

Test performance:

The positive control substance was degraded 66% in 14 days and 77% degradation was reached at the end of the test period.
The total CO2 release in the blank reached a total value of 12 mg CO2 per 2 litres of medium.
The difference of duplicate values for %-degradation of the test substance was always less than 20.

Parameter:

% degradation (CO2 evolution)

Value:

< 1

Sampling time:

28 d

Details on results:

The concentration was 37.0 and 37.2 mg test substance in 2 litres test medium. Hence, the theoretical CO2 production following complete degradation was 109.1 and 109.7 per 2 litres.
The relative degradation values calculated from the measurements performed during the test period revealed no significant (>10%) degradation of the test substance. In the toxicity control more than 25% degradation occurred in 14 days (based on ThCO2). Therefore, the test substance was assumed to be not inhibitory.

Results with reference substance:

The positive control contained 80.9 mg sodium acetate (ThCO2= 1.073 mg CO2/mg) resulting in a theoretical CO2 production following complete degradation of 86.8 mg per 2 litres. The toxicity control contained 80.9 mg sodium acetate and 37 mg test substance in 2 litres of test medium. Hence, the theoretical CO2 production following complete degradation of the test substance plus sodium acetate was 195.9 mg per 2 litres.

Reference 2

Endpoint:

biodegradation in water: ready biodegradability

Type of information:

experimental study

Adequacy of study:

supporting study

Study period:

1998-01-27 to 1998-02-24

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: GLP (QSE approved), limited documentation but still acceptable for evaluation.

Qualifier:

according to guideline

Guideline:

OECD Guideline 301 C (Ready Biodegradability: Modified MITI Test (I))

Version / remarks:

adopted 12 May 1981

Deviations:

no

GLP compliance:

yes

Oxygen conditions:

aerobic

Inoculum or test system:

activated sludge, non-adapted

Duration of test (contact time):

28 d

Initial conc.:

100 mg/L

Based on:

test mat.

Parameter followed for biodegradation estimation:

O2 consumption

Parameter:

% degradation (O2 consumption)

Value:

< 4

Sampling time:

28 d

Details on results:

The test results are summarised as follows :
1) Percent biodegradabilities based on oxygen consumption (n=3) were 1%, 2%, 4%.
2) The mean biodegradabilities (n=3) of each components based on GC analyses were No. 1 1%, No. 2 2%, No. 3 -4%, No. 4 -2%, No. 5 - 1 % and No. 6 -2%
3) Dissolved organic carbon was not detected in the test inoculum and it was proved that no water-soluble metabolite was produced.

Reference 3

Endpoint:

biodegradation in water: ready biodegradability

Type of information:

experimental study

Adequacy of study:

supporting study

Study period:

1997

Reliability:

4 (not assignable)

Rationale for reliability incl. deficiencies:

other: Only abstract/summary available.

Qualifier:

according to guideline

Guideline:

OECD Guideline 301 C (Ready Biodegradability: Modified MITI Test (I))

Version / remarks:

adopted 12 May 1981

Deviations:

not specified

GLP compliance:

not specified

Oxygen conditions:

aerobic

Inoculum or test system:

not specified

Duration of test (contact time):

28 d

Parameter followed for biodegradation estimation:

O2 consumption

Parameter:

% degradation (O2 consumption)

Value:

0

Sampling time:

28 d

The biological oxygen demand of the test substance was 0 mg/L ( n=3 ). No water-soluble metabolites was produced ( total organic carbon was 0 mg/L (n=3 )). After 28 day incubtion time, the six components were analyzed quantitatively by gas chromatographic method and it is proved that the six components remained to be unchanged ( biodegradability : 0 % ( n=3 )).

Description of key information

One study according to OECD guideline 301 B and two studies according to OECD 301 C are available. The studies revealed biodegradation rates ranging from 0 to < 4 %. Thus the substance is poorly biodegradable study performed.

Key value for chemical safety assessment

Biodegradation in water:

under test conditions no biodegradation observed

Additional information

The test substance is not readily biodegradable according to OECD criteria.