Fenspiride

Biodegradation in water: screening tests

Administrative data

Endpoint:

biodegradation in water: ready biodegradability

Type of information:

experimental study

Adequacy of study:

key study

Study period:

2009

Reliability:

1 (reliable without restriction)

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2009

Report date:

2009

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

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

GLP compliance:

yes (incl. QA statement)

Test material

Test material information

Constituent 1

Reference substance name:

Fenspiride

EC Number:

225-751-3

EC Name:

Fenspiride

Cas Number:

5053-06-5

Molecular formula:

C15H20N2O2

IUPAC Name:

8-(2-phenylethyl)-1-oxa-3,8-diazaspiro[4.5]decan-2-one

Test material form:

solid: particulate/powder

Specific details on test material used for the study:

Batch 831161/002

Study design

Oxygen conditions:

aerobic

Inoculum or test system:

activated sludge, non-adapted

Details on inoculum:

Activated sludge from a biologic sewage treatment plant was used. The chosen plant is treating mostly domestic sewage.
The sludge was taken from the activation basin of the ESN (Stadtentsorgung Neustadt) sewage treatment plant, 1m Altenschemel, NW-Lachen-Speyerdorf.
Date of collection: 12 dec 2008, batch no: 12122008
The sludge was filtrated, washed with tap water twice, then washed with and resuspended in test medium. It was then aerated for >= 12 hours. The dry matter was determined with 4400 mg suspended solids/litre.

Duration of test (contact time):

28 d

Initial test substance concentration

Initial conc.:

20 mg/L

Based on:

DOC

Parameter followed for biodegradation estimation

Parameter followed for biodegradation estimation:

CO2 evolution

Reference substance

Reference substance:

aniline

Results and discussion

% Degradation

% Degradation 1

Key result

Parameter:

% degradation (CO2 evolution)

Value:

26

Sampling time:

28 d

Remarks on result:

other: not readily biodegradable

% Degradation 2

Parameter:

% degradation (CO2 evolution)

Value:

26

Sampling time:

10 d

Any other information on results incl. tables

Emitted Carbon in mg/L

In the following table, the calculated emitted carbon is presented.

Table of emitted carbon in mg/L

Day	Control	Control	Positive Control 1	Positive Control 2	Test 1	Test 2	Abiotic Control	Toxicity Control
1	0.16	0.21	0.02	0.12	0.13	0.02	0.09	-0.05
3	0.47	1.03	2.91	2.21	0.44	0.62	0.15	5.63
6	0.52	1.11	7.66	9.07	0.63	1.26	-0.28	12.69
8	1.18	1.69	12.25	11.93	2.19	2.49	0.28	17.80
11	1.82	2.13	17.43	16.13	3.77	6.01	0.17	21.07
13	1.79	2.26	18.94	17.11	4.63	5.77	0.17	22.2
18	2.08	2.57	19.5	18.11	6.12	6.45	0.08	24.86
23	1.70	2.18	19.33	18.42	6.73	7.8	0.10	26.63
29	3.11	3.46	23.45	22.16	9.02	8.07	-0.07	27.7

 

Degradation Values

In the following table the percentage biodegradation is presented:

Table of degradation values in %

Day	Positive Control	Positive Control	Positive Control Mean	Test 1	Test 2	Test Mean	abiotic Control	Toxicity Control
1	-0.8	-0.3	-0.6	-0.2	-0.8	-0.5	0.4	-0.6
3	10.9	7.4	9.1	-1.5	-0.6	-1.1	0.7	12.3
6	34.5	41.6	38.0	-0.9	2.2	0.6	-1.3	30.0
8	54.4	52.9	53.7	3.8	5.3	4.5	1.3	41.3
11	77.9	71.3	74.6	9.0	20.2	14.6	0.8	48.2
13	85.2	76.0	80.6	13.0	18.8	15.9	0.8	50.9
18	86.5	79.5	83.0	19.0	20.7	19.9	0.4	56.9
23	87.6	83.0	85.3	24.0	29.4	26.7	0.5	62.4
29	101.6	95.1	98.3	28.7	24.0	26.3	-0.3	61.7

Applicant's summary and conclusion

Validity criteria fulfilled:

yes

Interpretation of results:

not readily biodegradable

Conclusions:

All validity criteria were met. Degradation behaviour of positive control and toxicity control was normal.
Regardless of the10-day-window the test item is considered as "not readily biodegradable".

Executive summary:

The test item was tested using a concentration of nominally 20 mg organic carbon/L (corresponding to 28.9mg 428 Base brute in test medium following OECD 301B and EUMeth0d C.4-C.

Aniline was chosen as positive control.

Activated sludge was used as inoculum (concentration in the test 25 mg dry matter/L).

The test was left running for 28 days.

All validity criteria were met. Degradation of the positive control was 75 % after nine days.

The following data were determined for the test item

10-day-window:                                                 day 11 -21

degradation at the end of 10-day-window             26%

degradation at the end of the test                           26%

pass level:                                                             60% at the end of 10-day-window

Therefore, regardless of the 10-day-window, the tested item is not readily biodegradable following OECD

301 B/EU C.4-C