3-hydroxypropiononitrile

Biodegradation in water: screening tests

Administrative data

Endpoint:

biodegradation in water: ready biodegradability

Type of information:

experimental study

Adequacy of study:

key study

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: Guideline study, GLP

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

1990

Report date:

1991

Materials and methods

Test guideline

Test guideline 1

Qualifier:

according to guideline

Guideline:

other: Directive EEC 79/831; Annex V; Part C: Biotic Degradation: Closed-Bottle-Test

Deviations:

no

Test guideline 2

Qualifier:

equivalent or similar to guideline

Guideline:

OECD Guideline 301 D (Ready Biodegradability: Closed Bottle Test)

Principles of method if other than guideline:

Method followed: Directive EEC 79/831; Annex V; Part C: Biotic Degradation: Closed-Bottle-Test, published in: O. J. (Official Journal of
the European Community) L251/3, 188-189

GLP compliance:

yes

Test material

Test material information

Constituent 1

Reference substance name:

3-hydroxypropiononitrile

EC Number:

203-704-8

EC Name:

3-hydroxypropiononitrile

Cas Number:

109-78-4

Molecular formula:

C3H5NO

IUPAC Name:

3-hydroxypropanenitrile

Details on test material:

- Supplier: Röhm GmbH, Germany
- Analytical purity: 99.08%
- Storage condition of test material: cool, dark

Study design

Oxygen conditions:

aerobic

Inoculum or test system:

sewage, predominantly domestic, non-adapted

Details on inoculum:

Source of inoculum/activated sludge (e.g. location, sampling depth, contamination history, procedure): Samples of
microorganisms of a secondary effluent were withdrawn from a sewage plant mainly fed with domestic sewage.

Duration of test (contact time):

>= 28 d

Initial test substance concentration

Initial conc.:

4.11 mg/L

Based on:

DOC

Parameter followed for biodegradation estimation

Parameter followed for biodegradation estimation:

O2 consumption

Details on study design:

TEST CONDITIONS
- Composition of medium: the test medium contained different mineral solutions, consisting of KH2PO4, K2HPO4,
Na2HPO4x2H20, NH4Cl at ph7.2 and MgSO4x 7 H2O, CaCl2, FeCl3 x 6 H2O.
- Test temperature: 20°C
- pH: 7.2
- Aeration of dilution water: for a period of about 20 hours
- Continuous darkness: yes

Reference substance

Reference substance:

aniline

Results and discussion

% Degradation

% Degradation 1

Key result

Parameter:

% degradation (O2 consumption)

Value:

63.2

Sampling time:

28 d

% Degradation 2

Key result

Parameter:

% degradation (O2 consumption)

Value:

4.6

Sampling time:

5 d

% Degradation 3

Key result

Parameter:

% degradation (O2 consumption)

Value:

5.5

Sampling time:

10 d

% Degradation 4

Key result

Parameter:

% degradation (O2 consumption)

Value:

33.1

Sampling time:

15 d

Any other information on results incl. tables

O2 consumption calc: Dt=[(mg BODx/1): (mg subs/1 x ThOD)]x100; Dt = Biodegradation at time t

mtx= O2-conc. of the mineral nutrient solut. with test mat. and with inoculum at time x (average of two parallels).

BODx = (mo-mtx)-(mo-mbx); mo= O2-conc of the mineral nutrient solut. without test material and without inoculum (average of two parallels)mbx = O2-conc of the mineral nutrient solut. without test material but with inoculum at time x (average of two parallels)

Applicant's summary and conclusion

Validity criteria fulfilled:

yes

Interpretation of results:

inherently biodegradable

Conclusions:

A degradation rate of 63% was obtained after 28 days, thus the test substance 2-Cyanoethanol has to be classificated as inherently biodegradable.

Executive summary:

According to the measured values of O2 -concentrations (in dependance of time, x) in the test vessels (with/without test 

material/inoculum)  via O2 -electrode, was calculated the BODx (Biological Oxygen Demand, in dependance of time, x). Via the BODx,

the ThOD and the concentration of the test substance 2 -Cyanoethanol in solution, the biotic Degradation at time x was calculated. The 

calculation of Dt, the biodegradation rate in time, was performed according to the following formula: Dt(%) = [(mg BODx /l) : (mg 

Subst / l  x ThOD)] x 100 Description of the curve of biodegradation (%): After a lag phase of about 10 days biodegradation takes 

place. Within the following 10 days, after 10% biodegradation was exceeded, about 40% degradation was obtained. Finally, a 

degradation rate of 63% was obtained. Since degradation time (28 days), belonging to the degradation rate of about > 60%, exceeded 

the 10 days window, 2-Cyanoethanol has to be classificated according to the criteria of  test evaluation as "inherently biodegradable".