Oxidised Crude Tall Oil

Toxicity to microorganisms

Administrative data

Endpoint:

activated sludge respiration inhibition testing

Type of information:

experimental study

Adequacy of study:

key study

Study period:

23 Aug 2013 to 24 Jan 2014

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: Guideline study under GLP

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2014

Report date:

2014

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

OECD Guideline 209 (Activated Sludge, Respiration Inhibition Test

GLP compliance:

yes (incl. QA statement)

Test material

Test material information

Constituent 1

Reference substance name:

Tall Oil Polymd., Oxidised

IUPAC Name:

Tall Oil Polymd., Oxidised

Constituent 2

Reference substance name:

68815-17-8

Cas Number:

68815-17-8

IUPAC Name:

68815-17-8

Constituent 3

Reference substance name:

EnvaMul™200

IUPAC Name:

EnvaMul™200

Test material form:

other: liquid

Details on test material:

- Name of test material (as cited in study report): EnvaMul™200
- Substance type: UVCB
- Physical state: Brown liquid
- Analytical purity: 100%
- Lot/batch No.: QD09
- Stability under test conditions: stable
- Storage condition of test material: cool and well ventilated area
- Expiry date: 09-Apr-2014

Sampling and analysis

Analytical monitoring:

no

Test solutions

Vehicle:

no

Test organisms

Test organisms (species):

activated sludge of a predominantly domestic sewage

Details on inoculum:

- Source: Guelph Wastewater Treatment Plant, Guelph, Ontario Canada
- Aeration: yes until treatment
- Pre-treatment: washed 3 times with laboratory water and diluted with reverse osmosis water to achieve 4 L of solution with 3 g/L dry matter. This solution was fed with 200 mL synthetic sewage feed and kept overnight (aerated at 20 °C)
- Day of treatment: inoculum kept aerated until test initiation, pH determination (7.8 range finding, 7.9 main test) and mixing prior to use

Study design

Test type:

static

Water media type:

freshwater

Limit test:

yes

Total exposure duration:

3 h

Test conditions

Nominal and measured concentrations:

Range finding study: 3 inoculum controls, 3 test concentrations (single at 10 and 100, triplicate at 1000 mg/L), 1 abiotic control, 3 reference substance controls (3.25, 10 and 32.5 mg/L )
Main study: 4 inoculum controls, 1 test concentration( 4 replicates at 1000 mg/L), 1 abiotic control, 3 reference substance controls (3.25, 10 and 32.5 mg/L )

Details on test conditions:

TEST SYSTEM
- Test vessel: 1L glass
- Aeration: 0.5-1.0 L/min
- Biomass loading rate: inoculum concentration 1.5 g/L

TEST MEDIUM / WATER PARAMETERS
- Source/preparation of dilution water: reverse osmosis water

OTHER TEST CONDITIONS
- Adjustment of pH: none
- Temperature: 20±2 °C

EFFECT PARAMETERS MEASURED : dissolved oxygen concentration over 30 seconds intervals over 10 minutes post exposure

TEST CONCENTRATIONS
- Range finding study: 10, 100 and 1000 mg/L
- Test concentrations: 1000 mg/L

Reference substance (positive control):

yes

Remarks:

3,5-dichlorophenol

Results and discussion

Effect concentrations

Effect concentrations 1

Duration:

3 h

Dose descriptor:

EC50

Effect conc.:

> 1 000 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

inhibition of total respiration

Remarks:

respiration rate

Effect concentrations 2

Duration:

3 h

Dose descriptor:

NOEC

Effect conc.:

1 000 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

inhibition of total respiration

Remarks:

respiration rate

Details on results:

one of the test substance replicates at 1000 mg/L in the pre-test was considered invalid (dissolved oxygen > 30% higher than other replicates and controls) and therefore a main test was performed.
In the main test at 1000 mg/L dissolved oxygen in all replicates was within the required ranges and similar to control values.
Oxygen consumption in abiotic controls was 0.9 mg O2/L/h. Therefore the results for the test solutions were adjusted.

Results with reference substance (positive control):

EC50 values between 2 and 25 mg/L (pre-test 10.2 mg/L, main test 3.6 mg/L)

Reported statistics and error estimates:

A respiration curve was plotted (DO against time). Only the linear part of the curve was used to calculate the slope.

Applicant's summary and conclusion

Validity criteria fulfilled:

yes

Conclusions:

The EC50 for respiration inhibition is > 1000 mg/L

Executive summary:

The substance was tested in a respiration inhibition test according to OECD 209 during 3 hours. No effects on respiration were seen at 1000 mg/L. Therefore it was concluded that the EC50 is > 1000 mg/L (NOEC 1000 mg/L).