4,4-Dimethyl-2-undecyl-2-oxazoline

Biodegradation in water: screening tests

Administrative data

Endpoint:

biodegradation in water: ready biodegradability

Type of information:

experimental study

Adequacy of study:

key study

Study period:

6th March 2017 - 24th November 2017

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Remarks:

GLP, Guidelines : OECD 301 F, NF EN ISO 10304-1

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2017

Report date:

2017

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

OECD Guideline 301 F (Ready Biodegradability: Manometric Respirometry Test)

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Test material

Test material information

Constituent 1

Reference substance name:

4,4-dimethyl-2-undecyl-4,5-dihydro-1,3-oxazole

EC Number:

686-853-5

Cas Number:

46921-17-9

Molecular formula:

C16H31NO

IUPAC Name:

4,4-dimethyl-2-undecyl-4,5-dihydro-1,3-oxazole

impurity 1

Reference substance name:

Unknown impurities

IUPAC Name:

Unknown impurities

impurity 2

Reference substance name:

IUPAC name not applicable

Molecular formula:

C16H33NO2

IUPAC Name:

IUPAC name not applicable

impurity 3

Reference substance name:

IUPAC name not applicable

Molecular formula:

C28H55NO3

IUPAC Name:

IUPAC name not applicable

Test material form:

liquid

Specific details on test material used for the study:

Purity : 88,0%
Storage conditions : Room temperature, away from light.

Study design

Oxygen conditions:

aerobic

Inoculum or test system:

activated sludge (adaptation not specified)

Details on inoculum:

Activated sludge were sampled in a wastewater treatment plant. Activated sludge were maintained in the laboratory under aeration condition before use. The concentration of suspended matters of the sludge used for the study was 3,62 g/L.

Duration of test (contact time):

ca. 28 d

Initial test substance concentration

Initial conc.:

ca. 2 722 other: mg O2/g

Based on:

ThOD

Remarks:

Test item ThODNO3 (Theoretical Oxygen Demand, with nitrification): 2722 mg O2 / g. Reference item ThOD (Theoretical Oxygen Demand): 1661 mg O2 / g

Parameter followed for biodegradation estimation

Parameter followed for biodegradation estimation:

O2 consumption

Details on study design:

A known quantity of test item was mixed with mineral test media and activated sludge. The preparation was agitated for 28 days in closed vessels containing CO2 trap. O2 uptake was calculated from measure of pressure in the closed vessels. Biodegradation rate was calculated from pressure measurements. Stock solutions were kept approximately at 4°C (refrigerator) without precipitate and were thus suitable to be used for the media preparation.

Test media was ventilated until a value close to saturation in air and pH stabilization (7.55 (criterion 7.4 ± 0.2) were obtained. Test media was kept 1 week for using at room temperature.

Seven bottles (610 mL) were simultaneous prepared as described below in order to have a final volume of solution (252 mL ± 1mL):
- 2 with test media and inoculum (blank solutions = control),
- 2 with test media, inoculum and test item (test item suspensions),
- 1 with test media, inoculum and reference item (reference suspension / procedure control),
- 1 with test media, inoculum, test item and reference item (toxicity control),
- 1 with test media, test item and sterilizing agent (abiotic sterile control).

Each bottle contained a CO2 trap by addition of NaOH pellets. The oxygen consumption was determined by manometry, determining the reduction of pressure in the tests flasks. The bottles were closed off with a system to measure head pressure and were stirred throughout the ready biodegradability test using a magnetic stirrer.

The test was carried out in a laboratory controlled room at 21°C +/- 1°C in the dark (temperature results were recorded on the sheet IM-0033). The BOD (Biological Oxygen Demand) values were given by OXITOP OC 110 Controller and depending from the initial parameters (volume of bottle: 610 mL, filling volume (252 mL ± 1 mL)).

Reference substance

Reference substance:

benzoic acid, sodium salt

Results and discussion

% Degradation

Key result

Parameter:

% degradation (O2 consumption)

Value:

>= 88 - <= 93

St. dev.:

5.4

Sampling time:

28 d

Remarks on result:

other: corrected with NO3 measurement

Remarks:

% of biodegradability at 28 days is corrected with NO3 measurement

Details on results:

Lag phase was detected between 2 and 4 days.
Percentage of biodegradation at 28 days was 88 and 93 %
60% biodegradation was achieved between 8 and 10 days (lag phase substracted).
10-d window was respected.

Validity:
- Reference control achieved the threshold level (60% of biodegradation) in 2 days (less than 14 days)
- Absolute deviation between two replicates of the test item was 5.4% after 28 days (less than 20%)
- Oxygen uptake of the control was approximately maximum at 13.3 mg/L in 28 days (less than 60 mg/L)
- pH values were in the range 7.-8.5
- Toxicity control showed a biodegradation rate greater than 25% occurred within 14 days, thus the test substance can be assumed to be not inhibitory.

Any other information on results incl. tables

*Corrected with NO3 measurement                   Biodegradation rate (%)  Time (days) Test item solution 1 Test item solution 2 Absolut difference (%) Reference control Toxicity Control   0 0  0  -  0  0   1 3.7  -4.4  8.1  33.1  17.1   2 11.8  0.7  11.0  58.3  34.5   3 14.9  5.8  9.0  72.0  48.1   4 22.3  11.7  10.6  79.2  56.0   5 31.0  16.0  15.0  79.5  57.7   7 41.0  29.2  11.8  85.1  65.1   10 47.8  51.9  4.1  92.8  76.6   14 73.8  69.4  4.4  94.6  89.2   21 86.4  80.9  5.5  94.1  96.2   28 94.4  87.3  7.1  96.7  99.1   28* 93.1*  87.8*  5.4*  97.2*  98.5*

Applicant's summary and conclusion

Validity criteria fulfilled:

yes

Interpretation of results:

readily biodegradable

Conclusions:

Ready biodegradability test of lauryl oxazoline by measurement of manometric respirometry over a 28-day period fulfils the requirements of OECD test No. 301F and concludes that this molecule is readily biodegradable.

Executive summary:

Objective:The scope of this study was, in compliance with the principles of Good Laboratory Pratices (GLP), to determine the ready biodegradability of lauryl oxazoline by measurement of manometric respirometry over a 28-day period.

 

Method summary: A known quantity of test item was mixed with mineral test media and activated sludge. The preparation was agitated for 28 days in closed vessels containing CO2 trap. O2 uptake was calculated from measure of pressure in the closed vessels. Biodegradation rate was calculated from pressure measurements.

 

Results:

	Lauryl Oxazoline
Percentage of biodegradation at 28 days	88 - 93 %
Conclusion	Readily Biodegradable

Ready biodegradability test of lauryl oxazoline by measurement of manometric respirometry over a 28-day period fulfils the requirements of OECD test No. 301F and concludes that this molecule is readily biodegradable.