Vinyl propionate

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:

12 February - 12 March 1997

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

guideline study without detailed documentation

Remarks:

study acc. to guideline from 1996, some parameters are not reported

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

1997

Report date:

1997

Materials and methods

Test guideline

Test guideline 1

Qualifier:

according to guideline

Guideline:

ISO 14593:1999 (Water quality - Evaluation of ultimate aerobic biodegradability of organic compounds in aqueous medium - Method by analysis of inorganic carbon in sealed vessels (CO2 headspace test))

Version / remarks:

draft version 1996

Deviations:

not specified

Test guideline 2

Qualifier:

equivalent or similar to guideline

Guideline:

OECD Guideline 310 (Ready Biodegradability - CO2 in Sealed Vessels (Headspace Test)

Version / remarks:

2014

Deviations:

not specified

GLP compliance:

yes

Test material

Test material information

Constituent 1

Reference substance name:

Vinyl propionate

EC Number:

203-293-5

EC Name:

Vinyl propionate

Cas Number:

105-38-4

Molecular formula:

C5H8O2

IUPAC Name:

ethenyl propanoate

impurity 1

Reference substance name:

Unknown impurities.

Molecular formula:

Not available as unknown impurities.

IUPAC Name:

Unknown impurities.

Test material form:

liquid: volatile

Specific details on test material used for the study:

Storage: with exclusion of oxygen, max. 25°C

Study design

Oxygen conditions:

aerobic

Inoculum or test system:

activated sludge, non-adapted

Details on inoculum:

- Source: activated sludge, non-adapted, from laboratory sewage treatment plants run with domestic and synthetic waste water
- Preparation of inoculum for exposure: no details reported
- Pretreatment: no details reported
- Concentration of sludge: 4 mg/l dry matter in the final mixture

Duration of test (contact time):

ca. 28 d

Initial test substance concentration

Initial test substance concentration 1

Initial conc.:

29 mg/L

Based on:

test mat.

Initial test substance concentration 2

Initial conc.:

17.3 mg/L

Based on:

other: ThOC

Parameter followed for biodegradation estimation

Parameter followed for biodegradation estimation:

inorg. C analysis

Details on study design:

TEST PRINCIPLE
The test substance, a defined test medium and the inoculum are incubated under standardised conditions. If biodegradation takes place, the bacteria produce CO2 from the organically bound carbon.
Every 7 days NaOH is injected in a part of the replicate flasks. Afterwards the biologically produced CO2 can be determined as inorganic carbon present in the solution.
The amount of total inorganic carbon (TIC) in relation to the applied amount of total organic carbon (TOC), is used to calculate the biodegradability.

TEST CONDITIONS
- Composition of test medium: not reported
- Test temperature: not reported
- pH: pH at day 28 was 6.9
- Continuous darkness: not reported

TEST SYSTEM
- Test flasks: 160 ml test flasks containing 100 ml test solution
- Test performed in triplicate (three test flasks)

CONTROL AND BLANK SYSTEM
BW: blind
NaOH - BW: NaOH, blind subtracted
KS: control substance (aniline, 26.7 mg/l, ThOC 20.9 mg/l)
PS: test substance (vinyl propionate, 29.0 mg/l, ThOC 17.3 mg/l)
IH: inhibition control (with test substance 29.0 mg/l, ThOC 17.3 mg/l and aniline 26.7 mg/l, ThOC 20.9 mg/l)


SAMPLING
Samples were taken on day 7, 14, 21 and 28.
Total inorganic carbon measurements were performed on samples from the control flasks (KS) and from the test substance flasks (PS).
Total inorganic carbon measurements and DOC-measurements were performed on samples from the blind flasks (BW) as well as NaOH minus blind flasks (NaOH - BW).

Reference substance

Reference substance:

aniline

Results and discussion

% Degradation

Key result

Parameter:

% degradation (inorg. C analysis)

Value:

92

Sampling time:

28 d

Remarks on result:

other: mean of three test flasks, test flask 1: 90%, test flask 2: 92%, test flask 3: 93%

Details on results:

- Duration of adaptation phase: < 7 days
- Duration of degradation phase: not determinable (plateau phase not yet reached at the end of the test)

Measured TIC values (mg/l) after 28 d, mean of three test flasks
NaOH-BW: 1.6 mg/l
BW: 3.8 mg/l
KS: 20.3 mg/l
PS: 19.5 mg/l
IH: 37.8 mg/l

pH:
BW: 7.3
KS: 6.9
PS: 6.9
IH: 6.7

Any other information on results incl. tables

Validity criteria:

The control substance reached >60% biodegradation based on TIC after 14 days, thus confirming suitability of inoculum and test conditions.

In the inhibition control, 80 -90% biodegradation based on TIC was reached, i.e. no inhibition was observed at the test concentration used.

Total inorganic carbon (TIC) content (mg/l) in blind test flasks after 28 days was < 15% of the amount applied in the test substance flasks (mg ThIC/l)

Maximum deviation in % degradation between the flasks was <20%.

Applicant's summary and conclusion

Validity criteria fulfilled:

yes

Interpretation of results:

readily biodegradable

Conclusions:

A 28-d CO2 headspace test (ISO/CD 14593) using activated sludge of laboratories sewage treatment plants indicated that vinyl propionate (CAS 105-38-4) reached a biodegradation of 92% based on inorganic carbon analysis. The substance reached the pass level of 60% for ready biodegradability within the 10-d window and, therefore, can be termed as readily biodegradable.

Executive summary:

A 28-d CO2 headspace test (ISO/CD 14593) using activated sludge of laboratories sewage treatment plants indicated that vinyl propionate (CAS 105-38-4) reached a biodegradation of 92% based on inorganic carbon analysis. The substance reached the pass level of 60% for ready biodegradability within the 10-d window and, therefore, can be termed as readily biodegradable.