1-bromohexane

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:

1996

Reliability:

2 (reliable with restrictions)

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

1996

Materials and methods

Test guideline

Test guideline 1

Qualifier:

according to guideline

Guideline:

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

Deviations:

no

Test guideline 2

Qualifier:

according to guideline

Guideline:

EU Method C.4-E (Determination of the "Ready" Biodegradability - Closed Bottle Test)

Deviations:

no

GLP compliance:

no

Test material

Test material information

Constituent 1

Reference substance name:

1-bromohexane

EC Number:

203-850-2

EC Name:

1-bromohexane

Cas Number:

111-25-1

Molecular formula:

C6H13Br

IUPAC Name:

1-bromohexane

Test material form:

not specified

Details on test material:

No details

Study design

Oxygen conditions:

aerobic

Inoculum or test system:

not specified

Duration of test (contact time):

29 d

Initial test substance concentration

Initial test substance concentration 1

Initial conc.:

4.03 mg/L

Based on:

test mat.

Initial test substance concentration 2

Initial conc.:

2 mg/L

Based on:

test mat.

Parameter followed for biodegradation estimation

Parameter followed for biodegradation estimation:

O2 consumption

Details on study design:

Four series of tests:
- 1: Medium + inoculum
- 2: Medium + inoculum + test substance
- 3: Medium + inoculum + test substance + reference substance
- 4: Medium + inoculum + reference substance
Each series was done with two flasks execpted the one with test substance which was done with 3 flasks.
Analyses done at 0, 7, 15, 22 and 29 days

Reference substance

Reference substance:

benzoic acid, sodium salt

Remarks:

At 2 mg/L in serie 3 and 4 mg/L in serie 4

Results and discussion

% Degradation

% Degradation 1

Parameter:

% degradation (O2 consumption)

Value:

-1.7

Sampling time:

7 d

% Degradation 2

Parameter:

% degradation (O2 consumption)

Value:

-0.5

Sampling time:

15 d

% Degradation 3

Parameter:

% degradation (O2 consumption)

Value:

1.1

Sampling time:

22 d

% Degradation 4

Parameter:

% degradation (O2 consumption)

Value:

7

Sampling time:

29 d

BOD5 / COD results

Results with reference substance:

%degradation of reference substance is : 80.5% after 7 days, 83.2% after 15 days, 85.9% after 22 days and 88.8% after 29 days

Applicant's summary and conclusion

Validity criteria fulfilled:

yes

Remarks:

%degradation of reference substance > 60% after 14 days; oxygen depletion in blank test < 1.5 mg/L after 28 days; %degradation of reference substance > 25% after 14 days in inhibition test; residual oxygen concentration on test flasks always > 0.5 mg/L

Interpretation of results:

under test conditions no biodegradation observed

Conclusions:

With a biodegradability of 7.0% after 28 days, 1-Bromohexane is determined as no biodegradable

Executive summary:

The biodegradability study of 1-Bromohexane gives a maximum of 7.0% after 28 days.

The validity criteria of the method were respected.

According to these criteria the test item cannot be considered as ready biodegradable.