Propiononitrile

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:

16/01/13-14/02/13

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

guideline study with acceptable restrictions

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2013

Report date:

2013

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

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

Version / remarks:

Presumed the method was used due to the volatility of the test substance

GLP compliance:

yes (incl. QA statement)

Test material

Test material information

Constituent 1

Reference substance name:

Propiononitrile

EC Number:

203-464-4

EC Name:

Propiononitrile

Cas Number:

107-12-0

Molecular formula:

C3H5N

IUPAC Name:

propanenitrile

Test material form:

liquid

Specific details on test material used for the study:

SOURCE OF TEST MATERIAL
Date and Quantity Received: 17 Dec 12; 302.8 g (GW)
Physical Description: Clear liquid Storage
Conditions: Room temperature
Purity: Not provided to testing facility
Stability: Not provided to testing facility

TREATMENT OF TEST MATERIAL PRIOR TO TESTING
Preparation of Test Substance Solution (~2 mg/L): Propionitrile (7.0 mg) was added to 3.5 L of mineral medium, and homogenized.
Preparation of Test Substance Solution (~10 mg/L): Propionitrile (35.0 mg) was added to 3.5 L of mineral medium, and homogenized

Study design

Oxygen conditions:

aerobic

Inoculum or test system:

activated sludge, non-adapted

Details on inoculum:

- Source of inoculum/activated sludge: Brazos River Valley Sewer Authority
- Laboratory culture: Lot No. Q130016.01
- Preparation of inoculum for exposure: Inoculum was added at the rate of 5 mL/L to the test substance, reference and toxicity reference solutions.

Duration of test (contact time):

28 d

Initial test substance concentration

Initial test substance concentration 1

Initial conc.:

ca. 2 mg/L

Based on:

test mat.

Initial test substance concentration 2

Initial conc.:

ca. 10 mg/L

Based on:

test mat.

Parameter followed for biodegradation estimation

Parameter followed for biodegradation estimation:

other: dissolved oxygen

Details on study design:

TEST CONDITIONS
- Composition of medium: All solutions were made to 1 L using deionized water. Solution A: 33.40 g Na2HPO4 . 2H2O 8.50 g KH2PO4 21.75 g K2HPO4 0.50 g NH4Cl Solution B: 36.40 g CaCl2 . 2H2O Solution C: 22.50 g MgSO4 . 7H2O Solution D: 0.25 g FeCl3 . 6H2O Eighteen milliliters of each of these prepared stock solutions (A, B, C and D) was added to 18 L of deionized water.
- Test temperature: 22-23°C
- Aeration of dilution water: BOD nutrients were added at the rate of 1 mL /L deionized water. The test medium was aerated for 20 minutes.
- Continuous darkness: yes

TEST SYSTEM
- Culturing apparatus: BOD bottle
- Number of culture flasks/concentration: 10
- Measuring equipment: YSI Model 5100 Dissolved Oxygen Meter

SAMPLING
- Sampling frequency: 7 days
- Sampling method: Two BOD bottles for each solution were removed at each sampling interval (0, 7, 14, 21 and 28 days). The oxygen in each duplicate set of solutions was measured and recorded at each interval

CONTROL AND BLANK SYSTEM
- Inoculum blank: Mineral media (3.5 L) was used as a blank and inoculum was added at the rate of 5 mL/L test media. This was homogenized for 15 minutes.
- Abiotic sterile control: Distilled aniline (7.0 mg) was added to 3.5 L of mineral medium, and homogenized.
- Toxicity control: Distilled aniline (7.0 mg) and 7.0 mg of Propionitrile were added to 3.5 L of mineral medium, and homogenized.

Reference substance

Reference substance:

aniline

Remarks:

Manufacturer: Sigma Aldrich, Lot: 35196, Expiration: Jul 2016

Results and discussion

Preliminary study:

Not applicable

Test performance:

absence of data

% Degradation

% Degradation 1

Key result

Parameter:

% degradation (O2 consumption)

Value:

110.1

Sampling time:

28 d

Remarks on result:

other: 2 mg/l

% Degradation 2

Parameter:

% degradation (O2 consumption)

Value:

-18.5

Sampling time:

7 d

Remarks on result:

other: 2 mg/L

% Degradation 3

Parameter:

% degradation (O2 consumption)

Value:

58.2

Sampling time:

14 d

Remarks on result:

other: 2 mg/l

% Degradation 4

Parameter:

% degradation (O2 consumption)

Value:

87.4

Sampling time:

21 d

Remarks on result:

other: 2 mg/l

% Degradation 5

Parameter:

% degradation (O2 consumption)

Value:

-6.5

Sampling time:

7 d

Remarks on result:

other: 10 mg/l

% Degradation 6

Parameter:

% degradation (O2 consumption)

Value:

14.5

Sampling time:

14 d

Remarks on result:

other: 10 mg/l

% Degradation 7

Parameter:

% degradation (O2 consumption)

Value:

25.1

Sampling time:

21 d

Remarks on result:

other: 10 mg/l

% Degradation 8

Key result

Parameter:

% degradation (O2 consumption)

Value:

24

Sampling time:

28 d

Remarks on result:

other: 10 mg/l

Details on results:

The test is based on a theoretical oxygen demand of 2.543 mg O2/mg Propionitrile. Since a sealed jar test begins with 9 mg/L O2 and at 10 mg/L of propionitrile, the oxygen demand will be 10 mg/L x 2.543 mgO2/mg = 25.43 mg/L O2. This test at theis concnetration should have not been performed.

BOD5 / COD results

BOD5 / COD

Key result

Parameter:

COD

Value:

2.543 other: mgO2/mg

Results with reference substance:

ThOD (mgO2/mg) 2.405;
Day 7 Net D.O. Depletion (mg/L) 2.545; % Degradation 52.9%
Day 14 Net D.O. Depletion (mg/L) 1.185; % Degradation 24.6%
Day 21 Net D.O. Depletion (mg/L) 3.435; % Degradation 71.4%
Day 28 Net D.O. Depletion (mg/L) 2.410; % Degradation 50.1%

Any other information on results incl. tables

Table 1. Concentration validation

Test Sample	Concentration (mg/L)
BOD media	Not Detected
2 mg/L	<1
10 mg/L	21.0620

Applicant's summary and conclusion

Validity criteria fulfilled:

yes

Remarks:

the test is valid only at the concentration of 2mg/l. At 10 mg/l the level of oxygen is below the limit.

Interpretation of results:

readily biodegradable, but failing 10-day window

Remarks:

at 2 mg/l

Conclusions:

For test substance, Propionitrile, at 2 mg/L, values of -18.5%, 58.2%, 87.4% and 110.1% biodegradation was obtained on Days 7, 14, 21 and 28; therefore, the test substance is considered readily biodegradable at 2 mg/L.
The test is based on a theoretical oxygen demand of 2.543 mg O2/mg Propionitrile. Since a sealed jar test begins with 9 mg/L O2 and at 10 mg/L of propionitrile, the oxygen demand will be 10 mg/L x 2.543 mgO2/mg = 25.43 mg/L O2. This test at theis concnetration should have not been performed.

Executive summary:

A study was performed meausure the biodegrability of Propiopionitrile following the OECD guidelines 301D. The study was conducted following GLP standard and it was considered reliable (Klimish 2) with restrictions. At 2 mg/l Propionitrile was readily biodegradable, with 58.2%, 87.4% and 110.1% biodegradation obtained on Days 14, 21 and 28 respectevely.

At 10 mg/l the level of dissolved oxygen fall below 0.5 mg/l after 21 days. limting so the activity of the inoculum. Furthermore, The test is based on a theoretical oxygen demand of 2.543 mg O2/mg Propionitrile. Since a sealed jar test begins with 9 mg/L O2 and at 10 mg/L of propionitrile, the oxygen demand will be 10 mg/L x 2.543 mgO2/mg = 25.43 mg/L O2. This test at theis concnetration should have not been performed.