2-Propenoic acid, 2-methyl-, C11-14-isoalkyl esters, C13-rich

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:

1989-07-18 to 1989-07-20

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

equivalent or similar to guideline

Guideline:

OECD Guideline 209 (Activated Sludge, Respiration Inhibition Test

Principles of method if other than guideline:

Five concentrations of the test material (1, 10, 100, 1000, 10000 mg/l) were tested. As the solubility of the substance was far exceeded and no
physical inhibitory effects (e.g. agglomeration of activated sludge) were observed, no further tests were performed.

GLP compliance:

yes

Analytical monitoring:

yes

Details on sampling:

- Sample storage conditions before analysis: 20 °C ±2 °C

Test organisms (species):

activated sludge of a predominantly domestic sewage

Details on inoculum:

- Pretreatment:
A sample of mixed liquor from the sewage plant was obtained and aerated during transportation to the laboratory.
Two samples of 10 ml were weighed and dried at 105 °C. The amount of solids was calculated and the wet sludge suspended with isotonic solution to yield a concentration of 3 g suspended solids per litre. Subsequently, the activated sludge was amended with 50 ml synthetic sewage per litre and aerated at 20 °C ±2 °C overnight.
Before use the amount of solids was determined and adjusted to 3 g / l. Aditionally, the pH-value was controlled. An adjustment was not necessary as the pH was in the accepted range of 6.0 – 8.0

Test type:

static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

180 min

Test temperature:

20 °C ±2 °C

pH:

pH 6 - 8

Nominal and measured concentrations:

1, 10, 100, 1000 and 10000 mg/l

Reference substance (positive control):

yes

Remarks:

3,5-Dichlorophenol

Duration:

180 min

Dose descriptor:

EC50

Effect conc.:

> 10 000 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

inhibition of total respiration

Remarks:

respiration rate

Details on results:

Five concentrations of the test material (1, 10, 100, 1000, 10000 mg/l) were tested. As the solubility of the substance was far exceeded and no
physical inhibitory effects (e.g. agglomeration of activated sludge) were observed, no further tests were performed.

Results with reference substance (positive control):

- Relevant effect levels:
The EC50 (3 hours) of 3,5-dichlorophenol was in the accepted range of 5 to 30 mg/l.

In every test the two control respiration rates were within 15 % of each other

Validity criteria fulfilled:

yes

Conclusions:

Isotridecyl methacrylate is of low toxicity to microorganisms relevant for biodegradation.
The EC50 (3 h) for the inhibition of biodegradation was > 10000 mg/L.

Executive summary:

Isotridecyl methacrylate was tested for toxicity to bacteria relevant for the biodegradation of the substance. In concentrations up to 10000 mg/l, which are far exceeding the water solubility of the substance, no inhibition of the oxygen consumption of the bacteria was observed within 180 min.

Therefore, it can be concluded that isotridecyl methacrylate is non-toxic to bacteria.

NOTE: Any of data in this dataset are disseminated by the European Union on a right-to-know basis and this is not a publication in the same sense as a book or an article in a journal. The right of ownership in any part of this information is reserved by the data owner(s). The use of this information for any other, e.g. commercial purpose is strictly reserved to the data owners and those persons or legal entities having paid the respective access fee for the intended purpose.

Description of key information

3 h EC50 > 10000 mg/L (equivalent to OECD TG 209, RL1, GLP)

Key value for chemical safety assessment

EC50 for microorganisms:

10 000 mg/L

Additional information

Isotridecyl methacrylate was tested for toxicity to bacteria relevant for the biodegradation of the substance. In concentrations up to 10000 mg/l, which are far exceeding the water solubility of the substance, no inhibition of the oxygen consumption of the bacteria was observed within 180 min.

Therefore, it can be concluded that Isotridecyl methacrylate is non-toxic to bacteria.