Coconut oil, reaction products with polyethylene glycol and trimethylolpropane

Toxicity to microorganisms

Link to relevant study record(s)

Reference

Endpoint:

activated sludge respiration inhibition testing

Type of information:

experimental study

Adequacy of study:

key study

Study period:

1996-08-30

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

guideline study with acceptable restrictions

Qualifier:

according to guideline

Guideline:

other: EG-Richtlinie L 133/118 vom 30.5.1988

GLP compliance:

yes

Analytical monitoring:

no

Vehicle:

no

Details on test solutions:

PREPARATION AND APPLICATION OF TEST SOLUTION (especially for difficult test substances)
- Method: The test substance was directly given into the test vessels in five different concentrations, the test vessels were 3 h incubated and stirred under permanent ventilation with clean, oil-free air in a water-filled pan
Controls: two replicates blank control, reference control (3,5-Dichlorophenol) in three different concentrations
- Evidence of undissolved material (e.g. precipitate, surface film, etc): no data

Test organisms (species):

activated sludge of a predominantly domestic sewage

Details on inoculum:

- Method of cultivation: not applicable
- Preparation of inoculum for exposure: approximately 5 l activated sludge of the sewage "Marl-Ost" was one-time sedimentated, three-times centrifuged each for 5 minutes 2000 min-1 and washed with 500 - 600 mL drinking water. The activated sludge was taken into 3.5 L drinking water and had a concentration of 3.603 g TS/L, that means for 500 mL test and 200 mL inoculum 1.44 g TS/L..

Test type:

flow-through

Water media type:

freshwater

Limit test:

no

Total exposure duration:

3 h

Post exposure observation period:

none

Hardness:

no data

Test temperature:

18 - 22 °C

pH:

7.6-7.8

Dissolved oxygen:

>= 2,5 mg/L

Nominal and measured concentrations:

57.4; 92.8; 189.4; 290.8; 380 mg/L

Details on test conditions:

TEST SYSTEM
- Test vessel: flasks
- Material, fill volume: glass, 500 ml fill volume
- Aeration: continuous
- Renewal rate of test solution (frequency/flow rate): not applicable
- No. of organisms per vessel: not applicable
- No. of vessels per concentration (replicates): 1
- No. of vessels per control (replicates): 2
- No. of vessels per vehicle control (replicates): not applicable
- Biomass loading rate: 200 mL inoculum; 1.44 g dry weight/L

EFFECT PARAMETERS MEASURED (with observation intervals if applicable) : Oxygen consumption, pH

Reference substance (positive control):

yes

Remarks:

3,5-Dichlorophenol

Key result

Duration:

3 h

Dose descriptor:

EC50

Effect conc.:

> 370 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

inhibition of total respiration

Remarks:

respiration rate

Results with reference substance (positive control):

- Results with reference substance valid: yes
- Relevant effect levels: EC50 = 5.1 mg/L

Validity criteria fulfilled:

yes

Executive summary:

Marlowet 4753 (Coconut oil, reaction products with polyethylene glycol and trimethylolpropane) was tested in Activated Sludge Respiration Inhibition Test according to EC guideline 88/302/EC. Within the tested concentration of 57.4; 92.8; 189.4; 290.8 and 380 mg/L there was no significant toxic effect. The determined positive effects were not proportional to increasing concentration. The EC50 was > 370 mg/L rounded up to two significant places. The test substance contents 98.4 % active substance.

Description of key information

Marlowet 4753 (Coconut oil, reaction products with polyethylene glycol and trimethylolpropane) was tested in Activated Sludge Respiration Inhibition Test according to EC guideline 88/302/EC. Within the tested concentration of 57.4; 92.8; 189.4; 290.8 and 380 mg/L there was no significant toxic effect. The determined positive effects were not proportional to increasing concentration. The EC50 was > 370 mg/L rounded up to two significant places. The test substance contents 98.4 % active substance.

Key value for chemical safety assessment

EC50 for microorganisms:

370 mg/L