ethyl 2-cyano-3-oxobutanoate

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:

2010

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: GLP , Guideline study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2010

Report date:

2010

Materials and methods

Test guideline

Test guideline 1

Qualifier:

according to guideline

Guideline:

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

Deviations:

no

Test guideline 2

Qualifier:

according to guideline

Guideline:

EU Method C.4-D (Determination of the "Ready" Biodegradability - Manometric Respirometry Test)

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Test material

Test material information

Constituent 1

Reference substance name:

ethyl 2-cyano-3-oxobutanoate

EC Number:

700-172-3

Cas Number:

634-55-9

Molecular formula:

C7 H9 NO3

IUPAC Name:

ethyl 2-cyano-3-oxobutanoate

Details on test material:

Test onditions : 21-22°C darkness
pH : 6.7-7.7

Study design

Oxygen conditions:

aerobic

Inoculum or test system:

activated sludge, domestic (adaptation not specified)

Duration of test (contact time):

28 d

Initial test substance concentration

Initial conc.:

1.5 g/L

Based on:

test mat.

Results and discussion

% Degradation

% Degradation 1

Parameter:

other: ThOD NO3

Value:

ca. 3

Sampling time:

9 d

% Degradation 2

Parameter:

other: ThODNO3

Value:

ca. 9

Sampling time:

10 d

% Degradation 3

Parameter:

other: ThODNO3

Value:

ca. 35

Sampling time:

11 d

% Degradation 4

Parameter:

other: THODNO3

Value:

ca. 70

Sampling time:

21 d

% Degradation 5

Parameter:

other: ThODNO3

Value:

ca. 72

Sampling time:

28 d

Details on results:

The mean biodegradation of Ethyl-2-cyano-3-oxobutanoate after 28 days of incubation was 73% (ThODNO3); the crite-rion of the 10 day window was passed on day 11.

Applicant's summary and conclusion

Validity criteria fulfilled:

yes

Interpretation of results:

readily biodegradable

Conclusions:

The degradation rate of Ethyl-2-cyano-3-oxobutanoate under consideration of nitrification reached 60% within the 10-day window and after 28 days of incubation. According to the guideline OECD 301, Ethyl-2-cyano-3-oxobutanoate is con-sidered to be readily biodegradable.

Executive summary:

The test flasks prepared were incubated at 22±. The pressure decrease in the reaction vessels was measured over complete experimental phase of 28 days using the BSB Sensomat system, Aqualytic Dortmund. The test flasks were closed gas-tight by a measuring head. Potassium hydroxide solution (45%) was used for trapping the produced carbon dioxide. The amount of O₂consumed by the activated sludge was calculated from the decrease of pressure in the reaction vessel.

The incubate temperature was 21 -22°C.

The pH was 7.4 -7.6 at the start of the test and pH 6.7 -7.7 at the end of the test.

The oxygen demand of the inoculum control (medium and inoculum) was 25 mg O₂/L and thus not greater than 60 mg O₂/L within 28 days as required by the test guideline.

The reference item sodium benzoate was sufficiently degraded to 75% after 14 days and to 78% after 28 days of incubation.

In the toxicity control containing both the test item and reference 56% biodegradation was noted within 14 days and 79% biodegradation was determined after 28 days of incubation based on ThOD NH4.

According to the test guidelines the test item can be assumed to be not inhibitory on theaerobic activatedsludge micro organisms because degradation was >25% within 14 days.

The degradation rate of Ethyl-2-cyano-3-oxobutanoate under consideration of nitrification reached 60% within the 10-day window and after 28 days of incubation. According to the guideline OECD 301, Ethyl-2-cyano-3-oxobutanoate is considered to be readily biodegradable.