2-hexyldecan-1-ol

Toxicity to microorganisms

Administrative data

Endpoint:

activated sludge respiration inhibition testing

Type of information:

experimental study

Adequacy of study:

supporting study

Study period:

July 10 to 16 2009

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

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 209 (Activated Sludge, Respiration Inhibition Test

Deviations:

yes

Remarks:

use of copper(II)sulphate pentahydrate as referrence item instead of 3,5-dichlorophenol

GLP compliance:

yes (incl. QA statement)

Test material

Test material information

Constituent 1

Details on test material:

- Name of test material (as cited in study report): 2-Octyl-1-dodecanol
- Substance type: pure active compound
- Physical state: liquid
- Lot/batch No.: 03508
- Expiration date of the lot/batch: January 1, 2011
- Storage condition of test material: room temperature, protected from moisture and light

Sampling and analysis

Analytical monitoring:

no

Test solutions

Vehicle:

no

Details on test solutions:

PREPARATION AND APPLICATION OF TEST SOLUTION (especially for difficult test substances)
- Method: The tets substance was weighed out directly into an Erlenmeyer flask and flled up with 250 ml autoclaved tap water and stirred for 24 hours.
- Controls: 2 control samples without test item were included, one at the beginnning and one at the end of the test
- Evidence of undissolved material (e.g. precipitate, surface film, etc): The test item formed drops and swam on the surface of the test solution.

Test organisms

Test organisms (species):

activated sludge of a predominantly domestic sewage

Details on inoculum:

- Pretreatment: The sludge was washed twice with autoclaved tap water and adjusted corresponding to a dry weight of 4.0 g/l +/- 10%
- Initial biomass concentration: 3.83 g/l dry sludge concentration

Study design

Test type:

static

Water media type:

freshwater

Limit test:

yes

Total exposure duration:

3 h

Test conditions

Test temperature:

18-22°C

pH:

6.72

Nominal and measured concentrations:

1000 mg/l (nominal)

Details on test conditions:

TEST SYSTEM
- Test vessel:
- Material, size, headspace, fill volume: 500 ml erlenmeyer flasks, DIN 12380
- Aeration: permanent
- No. of vessels per concentration (replicates): one
- No. of vessels per control (replicates): two
- Composition of tes medium: 200 ml inoculum, 16 ml synthetic waste water, 284 ml autoclaved tap water and test item concentration

EFFECT PARAMETERS MEASURED (with observation intervals if applicable) : oxygen depletion by means of an oximeter

TEST CONCENTRATIONS
- Range finding study
- Test concentrations: 10, 100 and 1000 mg/l
- Results used to determine the conditions for the definitive study: no inhibition at any of the concentrations tested

Reference substance (positive control):

yes

Remarks:

copper (II) sulphate pentahydrate p.a.

Results and discussion

Effect concentrations

Key result

Duration:

3 h

Dose descriptor:

EC0

Effect conc.:

>= 1 000 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

growth inhibition

Results with reference substance (positive control):

- Results with reference substance valid? Yes
- Relevant effect levels: EC50 = 99 mg/l

Any other information on results incl. tables

Table 1: respiration rates and Inhibition of Respiration of Test and Reference Item Concentrations
	concentration [mg/l]	Respiration rate [mgO2/l*h]	Inhibition [%]
Test item	1000	20	0
Control 1	-	20.4	-
Control 2	-	19.6	-
reference item	180	4	80
	100	9.6	52
	58	15.6	22

Applicant's summary and conclusion

Validity criteria fulfilled:

yes

Conclusions:

2-Octyldodecan-1-ol is not toxic at concentrations <= 1000 mg/l to activated sludge of a municipal sewage treatment plant.

Executive summary:

2-Octyldodecan-1-ol is not toxic at concentrations <= 1000 mg/l to activated sludge of a municipal sewage treatment plant.