2-(1-(2-hydroxy-3,5-di-tert-pentyl-phenyl)ethyl)-4,6-di-tert-pentylphenyl acrylate

Toxicity to microorganisms

Administrative data

Endpoint:

activated sludge respiration inhibition testing

Type of information:

experimental study

Adequacy of study:

key study

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: GLP Guideline study, with restrictions. Not in accordance with the currently accepted standards (OECD 209, 22 Jul 2010); e.g. the use of organic solvents, dispersants/emulsifiers to improve solubility should be avoided.

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

1995

Report date:

1995

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

OECD Guideline 209 (Activated Sludge, Respiration Inhibition Test

Version / remarks:

1984

GLP compliance:

yes

Test material

Test material information

Constituent 1

Reference substance name:

2-(1-(2-hydroxy-3,5-di-tert-pentyl-phenyl)ethyl)-4,6-di-tert-pentylphenyl acrylate

EC Number:

413-850-6

EC Name:

2-(1-(2-hydroxy-3,5-di-tert-pentyl-phenyl)ethyl)-4,6-di-tert-pentylphenyl acrylate

Cas Number:

123968-25-2

Molecular formula:

C37H56O3

IUPAC Name:

2-{1-[2-hydroxy-3,5-bis(2-methylbutan-2-yl)phenyl]ethyl}-4,6-bis(2-methylbutan-2-yl)phenyl prop-2-enoate

Test material form:

solid: pellets

Sampling and analysis

Analytical monitoring:

no

Test solutions

Vehicle:

yes

Details on test solutions:

PREPARATION AND APPLICATION OF TEST SOLUTION
- Method: A stock solution of 0.5 g/L was prepared in Milli-Q water (using Tween-80 as solubilizer). 100 mg/L stock solution (corresponding to 100 mL) added in each of the two test vessels (500 mL final volume).
- Controls: Two additive controls with Tween-80
- Chemical name of vehicle: Tween-80
- Concentration of vehicle in test medium: 0.006 % (v/v)

Test organisms

Test organisms (species):

activated sludge, domestic

Details on inoculum:

- Source of inoculum: Municipal sewage treatment plant s-Hertogenbosch, Netherlands
- Preparation of inoculum: The sludge was sieved and washed with tap-water.
- Laboratory culture: The batch was used max. up till 4 days after collection.
- Method of cultivation: 50 mL synthetic sewage feed was added daily. The sludge was kept aerated at 20±2°C until use.
- Suspended solid: 3.5 g/L (weighed and dried at ca. 105°C)

Study design

Test type:

static

Water media type:

freshwater

Limit test:

yes

Total exposure duration:

30 min

Test conditions

Test temperature:

20 ± 2°C

pH:

7.8 - 8.1

Nominal and measured concentrations:

Test substance: 100 mg/L (nominal)
Reference substance (3,5-dichlorophenol): 3.2, 10, and 32 mg/L (nominal)

Details on test conditions:

TEST SYSTEM
- Test vessel: 500 mL glass beakers and 300 mL oxygen bottles (for the O2 measurement)
- Fill volume of the test vessels: 300 mL
- Aeration: With clean, oil-free air
- No. of vessels per concentration (replicates): 2 (2 x 100 mg/L test substance)
- No. of vessels for reference substance: 3 (1 x 3.2, 10, and 32 mg/L)
- No. of vessels for control: 4
- No. of vessels for vehicle control: 2

TEST MEDIUM / WATER PARAMETERS
- Preparation of dilution water: Mili-Q water purified by reverse osmosis, subsequently passed over activated carbon and ion-exchange cartridges
- Synthetic sewage feed: Nutrients solution (16 g peptone, 11 g meat extract, 3 g urea, 0.7 g NaCl, 0.4 g CaCl2 * 2H2O, 0.2 g MgSO4 * 7 H2O, 2.8 g K2HPO4)

Reference substance (positive control):

yes

Remarks:

3,5-Dichlorophenol

Results and discussion

Effect concentrations

Duration:

30 min

Dose descriptor:

EC10

Effect conc.:

> 100 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

inhibition of total respiration

Remarks:

respiration rate

Details on results:

- No significant inhibition in the respiration rate of the sludge was recorded.

Results with reference substance (positive control):

- EC50 30min (3,5-dichlorophenol) = 14.55 mg/L (95 % limit: 11.68 - 18.73 mg/L)

Any other information on results incl. tables

Table 1: Inhibition (%) of microbial respiration after 30 min incubation

Concentration	% Inhibition
Control 1	-
Control 2	-
Control 3	-
Control 4	-
Control 1 with Tween-80	-
Control 2 with Tween-80	-
Reference (3.2 mg/L 3,5-dichlorophenol)	14
Reference (10 mg/L 3,5-dichlorophenol)	40
Reference (32 mg/L 3,5-dichlorophenol)	71
Test substance (100 mg/L)	4
Test substance (100 mg/L)	1