Reaction mass of (2E)-Tridec-2-enenitrile and (2Z)-Tridec-2-enenitrile and (3E)-Tridec-3-enenitrile and (3Z)-Tridec-3-enenitrile

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:

from 1998-05-26 to1998-07-07

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

OECD Guideline 301 F (Ready Biodegradability: Manometric Respirometry Test)

Version / remarks:

1992

Deviations:

no

GLP compliance:

yes

Oxygen conditions:

aerobic

Inoculum or test system:

activated sludge, domestic, non-adapted

Details on inoculum:

- Source of inoculum/activated sludge: Fresh activated sludge from a biological waste water treatment plant treating predominantly domestic sewage (City of Geneva, Aire)
- Preparation of inoculum for exposure: The sludge was collected in the morning, washed three times in the mineral medium (by centrifuging at 1000 g for 10 minutes, discarding the supernatant and resuspending in mineral medium) and kept aerobic until being used on the same day.
- Concentration of sludge: The concentration of the effluent in reaction mixture was 7.5 mg dry weight (as determined from 3.6, generally 1 to 3 mL).
- Concentration of the inoculum: 30 mg/L (dry weight)
- Dry weight of suspended solids: 3.026 g/L

Duration of test (contact time):

29 d

Initial conc.:

100 mg/L

Based on:

test mat.

Parameter followed for biodegradation estimation:

CO2 evolution

Details on study design:

TEST CONDITIONS
- Test medium: Fresh activated sludge from a biological waste water treatment plant treating predominantly domestic sewage.
- Test water: The test water used during this study is deionized water containing less than 10 mg/L dissolved organic carbon.
- Stock solutions: The following stock solutions were prepared:
Solution A:
KH2PO4: 8.5 g/L
K2HPO4: 21.75 g/L
Na2HPO42H2O: 33.4 g/L
NH4CI: 0.5 g/L

Solution B:
CaCI2: 27.5 g/L

Solution C:
MgSO4.7H2O: 22.5 g/L

Solution D:
FeCI3.6H2O: 0.25 g/L
HCI Conc.: one drop

- Mineral Medium: Prepared by mixing 50 mL of solution A and 2000 mL deionised water, adding 5 mL of each of the solutions B, C and D and making up to 5 litres with deionised water.
- Additional substrate: No
- Solubilising agent: No
- Test temperature: 22 °C
- pH adjusted: The pH was measured and if necessary adjusted to 7.4 ± 0.2 with phosphoric acid or potassium hydroxide.
- Aeration of dilution water: no
- Concentration of the inoculum: 30 mg/L
- Suspended solids concentration: 3.026 g/L

TEST SYSTEM
- Determination of the dry weight of suspended solids: The dry weight of suspended solids is determined by taking two 50 mL samples of the homogenized sludge, evaporating water on a steam bath, drying in an oven at 105 -110 °C for two hours and weighing the residue.
- Number of culture flasks/concentration: 8
- Preparation of the flaks for the test: All flasks were filled with 250 mL of mineral medium. Samples of test or reference substance, or both, were added. Then, a volume of suspended sludge corresponding to 7.5 mg dry weight (as determined from 3.6, generally 1 to 3 mL) was added.
- Measuring equipment: The respirometer used during this study is a SAPROMAT D 12, made by J. M. VOITH GmbH, D-7920 Heidenheim.
- Test temperature: 22 °C
- Test performed in closed vessels: yes
- Test performed in open system: No

DETAILS ON PRETREATMENT
- Pretreatment of the test substance: The test substance samples were weighed in small aluminium boats and added directly to the test flasks of the SAPROMAT, whereas reference substance samples (sodium benzoate) were added as 1.0 mL of a 25 mg/mL solution in mineral medium.

CONTROL AND BLANK SYSTEM
- Inoculum blank: Fresh activated sludge from a biological waste water treatment plant treating predominantly domestic sewage.
- Toxicity control: yes. A pair of flasks of the volumetric respirometer (SAPROMAT) was filled with mineral medium + test chemical (100 mg/L) + reference substance (100 mg/L) + inoculum and their respirations are recorded as for the other flasks.

STATISTICAL METHODS:
No statistical methods were performed.

Reference substance:

benzoic acid, sodium salt

Preliminary study:

The Theoretical Oxygen Demand (ThOD) of the test substance was determined to be 3.3 mg O2/mg and the Theoretical Oxygen Demand (ThOD) of the reference substance (sodium benzoate) was determined to be 1.67 mg O2/mg.

Test performance:

Degradation of sodium benzoate exceeded 65 % after 14 days: the activity of the inoculum is thus verified and the test is considered as valid. In addition all validity criteria were fulfilled.

Key result

Parameter:

% degradation (CO2 evolution)

Value:

88

Sampling time:

29 d

Details on results:

The test substance undergoes 88 % biodegradation after 29 days (87 % after 28 days) in the test conditions. Biodegradation started on day 2 and reached 75 % at the end of the 10-day window (days 2 to 12). Thus, the test substance is regarded as readily biodegradable according to this test. The curves obtained with the reference substance alone and with the test substance + reference substance showed no toxic effect of test substance on the micro-organisms at the test concentration.

Results with reference substance:

The degradation of sodium benzoate exceeded 40 % after 7 days and 65 % after 14 days.

Validity criteria fulfilled:

yes

Interpretation of results:

readily biodegradable

Conclusions:

The ready biodegradability of the test substance was investigated according to the OECD 301 D (1992). The test substance undergoes 88 % biodegradation after 29 days (87 % after 28 days). Biodegradation started on day 2 and reached 75 % at the end of the 10-day window (days 2 to 12), therefore the 10 day-windows criterion was fulfilled. Furthermore, the test substance showed no inhibitory effect on the microorganisms. The test substance is regarded as readily biodegradable according to this test.

Executive summary:

The ready biodegradability of the test substance was investigated according to the OECD 301 D - Manometric Respirometric Test (1992). The biodegradation of the test substance was followed by exposing it to microorganisms from the secondary effluent of a domestic waste water treatment plant over 29 days. A measured volume of inoculated mineral medium, containing a known concentration of test substance (100 mg/L) as the nominal sole source of organic carbon, was stirred in a closed flask at a constant temperature (± 1 °C) for up to 28 days. The concentration of the effluent in reaction mixture was 7.5 mg dry weight (as determined from 3.6, generally 1 to 3 mL), the concentration of the suspended solids was 3.026 g/L (dry weight) and the concentration of the inoculum was 30 mg/L. The consumption of oxygen was determined by measuring the quantity of oxygen (produced electrolytically) required to maintain constant the gas volume in the respirometer flask. The amount of oxygen taken up by the microbial population during biodegradation of the test chemical (corrected for uptake by blank inoculum, run in parallel) was expressed as a percentage of ThOD (Theoretical Oxygen Demand). As a reference compound (procedure control), 100 mg/L of sodium benzoate was tested simultaneously under the same conditions. The toxicity of the test chemical for the inoculum was checked. The reference substance alone and with the test substance + reference substance showed no toxic effect of the test substance on the micro-organisms at the test concentration. The test substance undergoes 88 % biodegradation after 29 days (87 % after 28 days). Biodegradation started on day 2 and reached 75 % at the end of the 10-day window (days 2 to 12), therefore the 10 day-windows criterion was fulfilled. The test substance is regarded as readily biodegradable according to this test.

Reference 2

Endpoint:

biodegradation in water: ready biodegradability

Type of information:

experimental study

Adequacy of study:

supporting study

Study period:

from 2000-06-30 to 2001-01-15

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

guideline study with acceptable restrictions

Qualifier:

according to guideline

Guideline:

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

Version / remarks:

1992

Deviations:

no

GLP compliance:

yes

Oxygen conditions:

aerobic

Inoculum or test system:

activated sludge, domestic, non-adapted

Details on inoculum:

- Source of inoculum/activated sludge: secondary effluent of a domestic sewage treatment plant of Odenthal, Germany
- Preparation of inoculum for exposure: Separation of coarse particles by filtration, aeration of mineral medium plus inoculum (filtrate) for 7 days.
- Concentration of sludge: The concentration of the effluent in reaction mixture was 5 mL/L.

Duration of test (contact time):

28 d

Initial conc.:

2.4 mg/L

Based on:

test mat.

Parameter followed for biodegradation estimation:

CO2 evolution

Details on study design:

TEST CONDITIONS
- Composition of medium: secondary effluent of a domestic sewage treatment plant of Odenthal, Germany
- Additional substrate: No
- Solubilising agent: No
- Test temperature: 20 +/- 1 °C

TEST SYSTEM
- Culturing apparatus: Waterbathes, incubators
- Number of culture flasks/concentration: The following type of flasks were used:
Test suspension (a measured volume of mineral medium containing a known concentration of the test substance (as the nominal sole source of organic carbon) and inoculum): 10 bottles.
Procedure control (in order to check the procedure, the reference chemical sodium benzoate is tested by setting up 2 flasks in parallel to the normal tests runs): 10 bottles
Inoculum blank (a measured volume of mineral medium containing only inoculum): 10 bottles
Toxicity control (containing test substance, reference substance and inoculum): 10 bottles

DETAILS ON PRETREATMENT
- Pretreatment of the test substance: No pretreatment of the test substance was performed. The test substance was weighed out on aluminium foil. This substance inclusive the aluminium foil was added direct to the test vessel.

CONTROL AND BLANK SYSTEM
- Inoculum blank: secondary effluent of a domestic sewage treatment plant of Odenthal, Germany
- Toxicity control: Yes. The test substance showed no inhibitory at the test concentration of 2.4 mg/L.

Reference substance:

benzoic acid, sodium salt

Preliminary study:

Preliminary investigations:
- ThOD of the test substance: 2979 mgO2/g
- Toxicity control: The used concentratios of the test substance did not show toxic effects to bacteria.

Test performance:

The validity criteria were fulfilled.

Key result

Parameter:

% degradation (CO2 evolution)

Value:

10

Sampling time:

28 d

Details on results:

At the end of the test, the test substance was biodegraded by an average of 10 %.

Results with reference substance:

The reference compound sodium benzoate was readily biodegraded by an average of 80 % after 28 days of exposure.

Validity criteria fulfilled:

yes

Interpretation of results:

under test conditions no biodegradation observed

Conclusions:

The ready biodegradability of the test substance was investigated according to the OECD guideline 301 D: Ready Biodegradability: Closed bottle test (1992). Under the test conditions, the test substance was found to be non-biodegradable over the test period of 28 days. Furthermore, the test substance showed no inhibitory effect on the microorganisms. At the end of the test, the test substance was biodegraded by an average of 10 %.

Executive summary:

The ready biodegradability of the test substance was investigated in accordance with the Council Directive 92/69/EEC Method C.4-E and in accordance with the OECD guideline 301 D: Ready Biodegradability: Closed bottle test (1992). The biodegradation of the test substance was followed by exposing it to microorganisms from the secondary effluent of a domestic waste water treatment plant over 28 days. The method assesses the ready biodegradability of a test substance under aerobic conditions at 20 ± 1°C in the dark. During this period the biodegradation was determined on the basis of the reduction of dissolved oxygen. The degree of biodegradation was calculated by the amount of oxygen taken up by the test substance (corrected for that in the blank inoculum control) as a percentage of ThOD or COD. As a reference compound (procedure control), 2.9 mg/L of sodium benzoate was tested simultaneously under the same conditions. In the toxicity control, the test substance showed no inhibitory effect on the microorganisms at the test concentration of 2.4 mg/L. In the procedure controls, the reference compound sodium benzoate was readily biodegraded by an average of 80 % after 28 days of exposure. At the end of the test (28 days), the test substance was biodegraded by an average of 10 %. Therefore, the test substance was found to be non-biodegradable under the test conditions.

Description of key information

The ready biodegradability of the test substance was investigated according to the OECD 301 F. The test substance undergoes 88 % biodegradation after 29 days (87 % after 28 days). The test substance is regarded as readily biodegradable according to this test.

Key value for chemical safety assessment

Biodegradation in water:

readily biodegradable

Additional information

The ready biodegradability of the test substance was investigated according to the OECD guideline 301 F - Manometric Respirometric Test (1992). The biodegradation of the test substance was followed by exposing it to microorganisms from the secondary effluent of a domestic waste water treatment plant over 29 days. As a reference compound (procedure control), 100 mg/L of sodium benzoate was tested simultaneously under the same conditions. The reference substance alone and with the test substance + reference substance showed no toxic effect of the test substance on the micro-organisms at the test concentration. The test substance undergoes 88 % biodegradation after 29 days (87 % after 28 days). Biodegradation started on day 2 and reached 75 % at the end of the 10-day window (days 2 to 12), therefore the 10 day-windows criterion was fulfilled. The test substance is regarded as readily biodegradable according to this test.

 

In addition the ready biodegradability of the test substance was investigated in a supporting study according to the OECD 301 D: Ready Biodegradability: Closed bottle test (1992). The test substance showed no inhibitory effect on the microorganisms. At the end of the test (28 days), the test substance was biodegraded by an average of 10 %. Nevertheless the key study showed that the substance was degraded 88 % after 29 days and the 10-day windows criterion was fulfilled, therefore the test substance is regarded as readily biodegradable.