1-bromodecane

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:

April-November 2000

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: see 'Remark'

Remarks:

Study conducted in compliance with agreed protocols, with no deviations from standard test guidelines and no methodological deficiences, which do not affect the quality of teh relevant results. The study report was conclusive, done to a valid guideline and the study was conducted under GLP conditions

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2000

Materials and methods

Test guideline

Test guideline 1

Qualifier:

according to guideline

Guideline:

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

Test guideline 2

Qualifier:

according to guideline

Guideline:

EU Method C.4-D (Determination of the "Ready" Biodegradability - Manometric Respirometry Test)

GLP compliance:

yes

Test material

Test material information

Constituent 1

Reference substance name:

1-bromodecane

EC Number:

203-955-3

EC Name:

1-bromodecane

Cas Number:

112-29-8

Molecular formula:

C10H21Br

IUPAC Name:

1-bromodecane

Details on test material:

Lot number: 6502/99
Appearence: clear colorless to slightly yellow liquid
Assay: 98.8%w
Water solubility: 0.196 mg/L

Study design

Oxygen conditions:

aerobic

Inoculum or test system:

sewage, predominantly domestic (adaptation not specified)

Details on inoculum:

Sample taken from secondary effluent of Versailles sewage plant

Duration of test (contact time):

28 d

Initial test substance concentration

Initial conc.:

13.99 mg/L

Based on:

test mat.

Parameter followed for biodegradation estimation

Parameter followed for biodegradation estimation:

O2 consumption

Details on study design:

A measured volume (250 ml) of inoculated mineral medium, containing 13.99 mg/L of 1-bromodecane with a theoritical oxygen demand (ThOD) of 2.1702 mgO2/mg as the sole source of organic carbon, is stirred in a closed flask at a constant temperature of 22.5 ±1°C for up to 28 days.

Reference substance

Reference substance:

benzoic acid, sodium salt

Remarks:

at 100 mg/L

Results and discussion

% Degradation

Parameter:

% degradation (O2 consumption)

Value:

64

Details on results:

On the test conditions, the percentage of biodegradation of 1-bromodecane reached 69% within 20 days (plateau) and 73% at the end of the test (28 days).
The 10-d window ended on day 14.

BOD5 / COD results

BOD5 / COD

Parameter:

BOD5

Value:

1.59 mg O2/g test mat.

Results with reference substance:

The percentage of degradation of the reference item has reached a level of 95 % by 14 days which is above the level of 60 % for ready biodegradability.

Any other information on results incl. tables

The method was applied with respect to its quality criteria:

- the difference of extremes of replicate values of the removal of test chemical at the plateau, at the end of the test, or at the end of the 10-d window, was less than 20% ;

- the percentage of degradation of the reference item has reached a level of 95% by 14 days which is above the level of 60% for ready biodegradability ;

- the oxygen uptake of the inoculum blank was far below the normal ;

- pH value in the test suspension was 7.43 at day 28 which is in the range of 6-8.5 ;

- in the toxicity control flasks, containing both the reference item and 1-bromodecane, the percentage biodegradation reached 56% after 14 days.

Since this value is higher than 25%, the test item is not inhibitory for inoculum.

Applicant's summary and conclusion

Validity criteria fulfilled:

yes

Interpretation of results:

readily biodegradable

Conclusions:

According to OECD guideline 301, the test item can be considerd as ready biodegradable.

Executive summary:

The biodegradability study of 1 -bromodecane conducted following Method C4 of Regulation 92/69/CEE gives a maximum biodegradation level of 73 % in 28 days.

After the 10-day window, the percentage of biodegradation is 64 %.

The test item did not inhibit the micro-organisms.
The validity criteria of the method were respected.

According to these criteria the test item can be considerd as ready biodegradable.