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Environmental fate & pathways

Biodegradation in water: screening tests

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Administrative data

Endpoint:
biodegradation in water: ready biodegradability
Type of information:
experimental study
Adequacy of study:
key study
Study period:
19 March - 16 April 2015
Reliability:
1 (reliable without restriction)
Rationale for reliability incl. deficiencies:
other: Reliability 1 is assigned because the study conducted according to OECD TG 301D in compliance with GLP, without deviations that influence the quality of the results.

Data source

Reference
Reference Type:
study report
Title:
Unnamed
Year:
2015
Report Date:
2015

Materials and methods

Test guidelineopen allclose all
Qualifier:
according to
Guideline:
OECD Guideline 301 D (Ready Biodegradability: Closed Bottle Test)
Version / remarks:
(1992)
Qualifier:
according to
Guideline:
EU Method C.4-E (Determination of the "Ready" Biodegradability - Closed Bottle Test)
Version / remarks:
(2008)
Qualifier:
according to
Guideline:
other: ISO Standard 10707, Water Quality - Evaluation in an aqueous medium of the "ultimate” aerobic biodegradability of organic compounds - Method by analysis of biochemical oxygen demand (closed bottle test) (1994)
GLP compliance:
yes

Test material

Reference
Name:
Unnamed
Type:
Constituent
Test material form:
other: Liquid
Details on test material:
- Name of test material in report: IFF 09-0035
- Physical state: Clear liquid
- Storage condition of test material: At room temperature protected from light

Study design

Oxygen conditions:
aerobic
Inoculum or test system:
activated sludge, domestic, non-adapted
Details on inoculum:
- Source of activated sludge: The source of test organisms was secondary effluent freshly obtained from a municipal sewage treatment plant: 'Waterschap Aa en Maas', 's-Hertogenbosch, The Netherlands, receiving predominantly domestic sewage.
- Pretreatment: Secondary effluent was filtered through a coarse filter paper, the first 200 mL was discarded. The filtrate was kept aerated until inoculation.
- Inoculation: 4 mL filtrate of secondary effluent per litre of final volume
Duration of test (contact time):
28 d
Initial test substance concentrationopen allclose all
Initial conc.:
1 mg/L
Based on:
test mat.
Initial conc.:
3 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 in accordance with OECD 301 D
- Test temperature: 21.8 - 22.5 °C
- pH: 7.4.- 7.5 (at the start of the test)
- pH adjusted: no
- Continuous darkness: yes

TEST SYSTEM
- Culturing apparatus: 250-300 mL BOD bottles with glass stoppers
- Number of culture flasks/concentration:
Individual BOD bottles were prepared for each measuring point, except that the bottles measured at the start were also measured on day 7.
Parallel groups were prepared to allow duplicate measurements of oxygen consumption at the test interval
- Measuring equipment: WTW oxygen meter supplied with a WTW CellOx 325 oxygen electrode, electrolyte type ELY/G
- Test performed in closed vessels due to significant volatility of test substance: Yes

DETERMINATION OF OXYGEN CONCENTRATION
- Frequency: In duplicate; immediately at the start of the experiment (day 0), and at day 7, 14, 21 and 28.

CONTROL AND BLANK SYSTEM
- Inoculum blank: Yes
- Abiotic sterile control: No
- Toxicity control: Yes
- Other: Procedure control (containing reference substance and inoculum)
Reference substance
Reference substance:
acetic acid, sodium salt

Results and discussion

% Degradationopen allclose all
Parameter:
% degradation (O2 consumption)
Value:
25
Sampling time:
28 d
Remarks on result:
other: at 1 mg/L
Parameter:
% degradation (O2 consumption)
Value:
40
Sampling time:
28 d
Remarks on result:
other: at 3 mg/L
Details on results:
At both test concentrations, a significant biodegradation of IFF 09-0035 was observed, i.e. an average biodegradation of 25% and 40% after 28 days for the low and high concentration respectively. Thus, the criterion for ready biodegradability (at least 60% biodegradation within a 14-day window) was not met.

BOD5 / COD results

Results with reference substance:
The mean percentage degradation was >60%) after 14 d (actual: 74%).

Any other information on results incl. tables

In the toxicity control more than 25% biodegradation occurred within 14 days (40%, based on ThOD). Thus IFF 09-0035 does not inhibit microbial activity.

Table:Biodegradation on various days during the 28-day period of incubation

Test medium

Concentration

% Biodegradation after x days1)

 

(mg/l)

0

7

14

21

28

 

Procedure control A2)

2

0

56

73

 

Procedure control B2)

2

0

75

75

 

Procedure control mean A and B

2

0

66

74

 

Difference between duplicate values

2

0

19

2

 

 

Test substance low A3)

1

0

1

14

21

24

 

Test substance low B3)

1

0

-1

15

20

26

 

Test substance low mean A and B

1

0

0

15

21

25

 

Difference between duplicate values

1

0

2

1

1

2

 

 

Test substance high A3)

3

0

3

22

32

38

 

Test substance high B3)

3

0

2

22

32

41

 

Test substance high mean A and B

3

0

3

22

32

40

 

Difference between duplicate values

3

0

1

0

0

3

 

 

Toxicity control A

2/14)

0

26

40

 

Toxicity control B

2/14)

0

26

40

 

Toxicity control mean A and B

2/14)

0

26

40

 

 

 

 

 

 

 

 

 

Difference between duplicate values

2/14)

0

0

0

 

 

1): Calculations were performed with the mean oxygen concentrations of t=0 and the oxygen depletion

   Except for the percentages biogradation, all calculations were performed without rounding off.

2): ThOD positive control sodium acetate: 0.78 mg O2/mg

3): ThOD test substance: 2.72 mg O2/mg

4): Toxicity control contains sodium acetate and test substance.

Applicant's summary and conclusion

Validity criteria fulfilled:
yes
Remarks:
See Overall remarks
Interpretation of results:
other: Although substantial biodegradation was recorded after 28 days of incubation, IFF 09-0035 was not readily biodegradable under the conditions of the closed bottle test.
Conclusions:
The substance showed 25% biodegradation at a concentration of 1 mg/L and 40% biodegradation at a concentration of 3 mg/L after 28 days in a closed bottle test according to OECD TG 301D. The suubstance is designed as not readily biodegradable.
Executive summary:

The ready biodegradability of IFF 09-0035 was investigated in a study conducted in accordance with OECD TG 301D and GLP. The concentrations tested were 1 and 3 mg/L test substance. The test substance biodegraded for 25% at 1 mg/L and for 40% at 3 mg/L within 28 days. The substance was not toxic to the inoculum (40% biodegradation in the toxicity control after 14 days). IFF 09 -0035 is not considered as readily biodegradable.