Decene

Biodegradation in water: screening tests

Administrative data

Endpoint:

biodegradation in water: ready biodegradability

Type of information:

experimental study

Adequacy of study:

key study

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: Guideline study without detailed documentation

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

1995

Report date:

1995

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

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

GLP compliance:

yes

Test material

Test material information

Constituent 1

Reference substance name:

Decene

EC Number:

246-870-7

EC Name:

Decene

Cas Number:

25339-53-1

Molecular formula:

C10H20

IUPAC Name:

dec-1-ene

Details on test material:

- Name of test material (as cited in study report): n-Decene (Commercial name: n-OLEFINA C10)
- Substance type: pure active substance
- Physical state: liquid
- Stability under test conditions: no data
- Storage condition of test material: no data

Study design

Oxygen conditions:

aerobic

Inoculum or test system:

activated sludge, domestic, non-adapted

Details on inoculum:

- Source of inoculum/activated sludge: from the aeration basin of the municipal water treatment plant of the city of Novara, Italy
- Laboratory culture: no
- Storage conditions: aerated at room temperature
- Storage length: 24 h
- Preparation of inoculum for exposure: no data
- Pretreatment: no data
- Concentration of sludge: 30 mg/L suspended solids
- Initial cell/biomass concentration: no data
- Water filtered: no data

Duration of test (contact time):

30 d

Initial test substance concentration

Initial conc.:

9.3 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: according to Standard Operating Procedures of the Test Institute, no details mentioned
- Test temperature: 22 ± 0.2 °C
- pH: no data
- Aeration of dilution water: no data
- Suspended solids concentration: 30 mg/L
- Continuous darkness: no data


TEST SYSTEM
- Culturing apparatus: closed flasks with a test volume of 500 mL, no further details mentioned
- Number of culture flasks/concentration: 2
- Measuring equipment: volume reduction and calculated oxygen uptake were measured daily, no further details mentioned
- Details of trap for CO2: evolved CO2 was absorbed in soda lime


CONTROL AND BLANK SYSTEM
- Inoculum blank: yes
- Abiotic sterile control: no
- Toxicity control: no


STATISTICAL METHODS: no statistics performed

Reference substance

Reference substance:

benzoic acid, sodium salt

Remarks:

15.5 mg/L

Results and discussion

Preliminary study:

not performed

Test performance:

Biodegradability was assessed by means of manometric respirometry. A measured volume (500 mL) of inoculated medium containing a known amount of test substance (18.6 mg) was stirred in a closed flask. The consumption of oxygen was determined from the reduction in volume of the air contained in the apparatus. The test compound was directly added to the test flasks by means of a microsyringe due to insolubility in water. For each day, volume reduction and calculated oxygen uptake for the test compound and for the blank, in duplicate, were reported together with the corrected values. The same set of values for the reference control was also reported.

% Degradation

Parameter:

% degradation (O2 consumption)

Value:

80.9

Sampling time:

28 d

Details on results:

Lag phase: 3 days
Degradation phase: 14 days
10-day window: days 3 to day 13
Degradation at the end of the 10-day window: 64.9 % (mean)
Degradation at plateau: ¿ 81 % (mean)

BOD5 / COD results

Results with reference substance:

The reference compound reached the pass-level of 60% at day 5.

Any other information on results incl. tables

Table: Biodegradation kinetics

Time [days]	% biodegradation
	test 1	test 2	mean	reference substance
1	0	0	0	14.8
2	4.5	6.5	5.5	39.7
5	28.5	27.5	28.0	68.1
6	35.5	33.5	34.5	74.7
7	39.6	39.6	39.6	74.7
8	45.6	44.6	45.1	78.0
9	50.9	50.9	50.9	80.8
12	63.8	63.8	63.8	80.7
13	64.0	65.9	64.9	83.3
14	67.1	70.1	68.6	86.0
15	67.1	70.1	68.6	86.0
16	70.8	72.8	71.8	86.9
19	74.3	75.3	74.8	84.9
21	76.1	76.1	76.1	84.9
22	78.8	78.8	78.8	85.7
23	79.3	79.3	79.3	84.9
26	81.0	83.0	82.0	87.1
28	80.9	80.9	80.9	88.0
30	78.9	80.9	79.9	86.9

Applicant's summary and conclusion

Validity criteria fulfilled:

yes

Interpretation of results:

readily biodegradable

Conclusions:

The test substance n-OLEFINA C10 was readily biodegradable, measured by manometric respirometry.
The reported test was considered valid meeting the following conditions:
Oxygen uptake of inoculum blank was less than 60 mg/L at day 28, the difference between replicate values was less than 20% at day 28, percentage of degradation of reference control reached 60% pass-level before day 14.

Executive summary:

The biodegradation of the test substance n-Decene measured by manometric respirometry according to OECD 301F was 80.9 % after 28 days of incubation.

The full set of relevant degradation parameters, as derived from the graph of percentage degradation , was as follows:

Lag phase: 3 days

Degradation phase: 14 days

10-day window: days 3 to day 13

Degradation at the end of the 10-day window: 64.9 % (mean)

Degradation at plateau: ¿ 81 % (mean)

Therefore the test substance was considered to be readily biodegradable.