2-Heptanol, 3,6-dimethyl-

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:

From 6 March 2013 to 7 October 2013

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: According to the OECD Guideline and it is GLP.

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2013

Report date:

2013

Materials and methods

Test guideline

Test guideline 1

Qualifier:

according to guideline

Guideline:

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

Deviations:

no

Test guideline 2

Qualifier:

according to guideline

Guideline:

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

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Test material

Test material information

Constituent 1

Reference substance name:

3,6-dimethylheptan-2-ol

EC Number:

801-829-8

Cas Number:

1247790-47-1

Molecular formula:

C9H20O

IUPAC Name:

3,6-dimethylheptan-2-ol

Details on test material:

- Physical state: clear colorless liquid
- Storage condition of test material: room temperature in the dark

Study design

Oxygen conditions:

aerobic

Inoculum or test system:

sewage, predominantly domestic, non-adapted

Details on inoculum:

A mixed population of sewage treatment micro-organisms was obtained on 14 June 2013 from the final effluent stage of the Severn Trent Water Plc sewage treatment plant at Loughborough, Leicestershire, UK, which treats predominantly domestic sewage.
The sample of effluent was filtered through coarse filter paper and maintained on aeration in a temperature controlled room at 21±1ºC prior to use.

Duration of test (contact time):

28 d

Initial test substance concentration

Initial conc.:

100 mg/L

Based on:

test mat.

Details on study design:

The test item at a concentration of 100 mg/L was exposed to sewage treatment micro-organisms with mineral medium in sealed culture vessels in diffuse light at 22±1ºC for 28 days.
The degradation of the test item was assessed by the measurement of daily oxygen consumption values on Days 0 to 28. Control solutions with inoculum and the reference item, aniline, together with a toxicity control were used for validation purposes.

Preparation of Test System:
The following test preparations were prepared and inoculated mineral medium to act as the inoculum control
a) Three replicate bottles containing inoculated mineral medium to act as the inoculum control.
b)Two replicate bottles containing inoculated mineral medium and the reference item, aniline, at a concentration of 100 mg/L.
c) Three replicate bottles containing inoculated mineral medium and the test item at a concentration of 100 mg/L.
d) Two replicate bottles containing inoculated mineral medium the reference item, aniline, at a concentration of 100 mg/L and the test item at a concentration of 100 mg/L to act as toxicity control vessels.

All vessels were inoculated with the prepared inoculum at a rate of 1% v/v.

Reference substance

Reference substance:

aniline

Results and discussion

% Degradation

Value:

91

BOD5 / COD results

Results with reference substance:

Aniline (procedure control) attained 77% degradation after 14 days and 76% degradation after 28 days thereby confirming the suitability of the inoculum and test conditions.

Any other information on results incl. tables

BOD and Biodegradation Values

Sample Description		ThOD	Day 7		Day 14		Day 28
			BOD (mg O2/L)	Degradation (%)	BOD (mg O2/L)	Degradation (%)	BOD (mg O2/L)	Degradation (%)	Mean Biodegradation (%)
Inoculum Control	R1	-	12,5	-	26,94	-	69,34	¡-	-
	R2	-	13,28	-	29,66	-	78,52	-
Procedure Control		309	220,04	67	265,06	77	308,54	76	-
Test Item	R1	292	22,86	3	224,36	67	320,04	84	91
	R2	292	49,68	13	278,48	86	360,86	98
Toxicity Control		601	207,58	32	441,78	69	543,28	78	-

Applicant's summary and conclusion

Validity criteria fulfilled:

yes

Interpretation of results:

readily biodegradable

Conclusions:

The test item attained 91% degradation after 28 days and satisfied the 10 -Day window validation criterion, whereby 60% degradation must be attained within 10 days of the degradation rate exceeding 10%. The test item can therefore be considered to be readily biodegradable under the stric terms and conditions of OECD Guideline No.301F.

Executive summary:

The study was performed to assess the ready biodegradability of the test item in an aerobic aqueous media. The method followed was designed to be compatible with the OECD Guidelines for Testing of Chemicals (1992) No. 301F, "Ready Biodegradability; Manometric Respiratory Test" refered as method C.4-D of Commission Regulation (EC) No. 440/2008.

The test item at a concentration of 100 mg/L was exposed to sewage treatment micro-organisms with mineral medium in sealed culture vessels in diffuse light at 22±1ºC for 28 days.

The degradation of test item was assessed by the measurement of daily oxygen consumption values on Days 0 to 28. Control solutions with inoculum and the reference item, aniline, together with a toxicity control were used for validation purposes.

The test item attained 91% degradation after 28 days and satisfied the 10 -Day window validation criterion, whereby 60% degradation must be attained within 10 days of the degradation rate exceeding 10%. The test item can therefore be considered to be readily biodegradable under the stric terms and conditions of OECD Guideline No.301F.