Dodecanenitrile

Biodegradation in water: screening tests

Link to relevant study record(s)

Reference

Endpoint:

biodegradation in water: ready biodegradability

Type of information:

experimental study

Adequacy of study:

key study

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

study well documented, meets generally accepted scientific principles, acceptable for assessment

Justification for type of information:

Data is from peer reviewed journal

Qualifier:

according to guideline

Guideline:

other: as mentioned below

Principles of method if other than guideline:

Biodegradation study was conducted for 45 days for evaluating the percentage biodegradability of test substance Dodecanenitrile.

GLP compliance:

not specified

Specific details on test material used for the study:

- Name of test material (IUPAC name): Dodecanenitrile
- Molecular formula: C12H23N
- Molecular weight: 181.321 g/mole
- Smiles notation: C(CCCCCC)CCCCC#N
- InChl: 1S/C12H23N/c1-2-3-4-5-6-7-8-9-10-11-12-13/h2-11H2,1H3
- Substance type: Organic
- Physical state: colourless liquid

Oxygen conditions:

aerobic

Inoculum or test system:

other: Pseudomonas fluorescens

Details on inoculum:

- Source of inoculum/activated sludge (e.g. location, sampling depth, contamination history, procedure): A bacterial strain Pseudomonas fluorescens was used as a test inoculum isolated from the undecanenitrile broth platings and identified by using Rapid NFT Strips (API Systems S.A.) and also isolated directly from the original enrichment culture by plating onto 0.1 strength Trypticase soy broth (BBL Microbiology Systems) solidified with purified agar (Difco). It was identified as a strain of Pseudomonas aeruginosa by using the Rapid NFT Strips.
- Method of cultivation: Pseudomonas fluorescens strain was grown in nitrogen-free medium with 0.1% glucose and 1% shale oil (identical conditions as the parent enrichment culture with the shale oil as the sole nitrogen but not the sole carbon source) or Bushnell-Haas medium with 0.3% shale oil (shale oil as the sole carbon but not the sole nitrogen source).
- Preparation of inoculum for exposure: Several soil sources contaminated with petroleum, including soils from oily-sludge land farming and drill cores, were used as sources of inocula for enrichment cultures. Ten grams of each soil was added to 100 ml of a nitrogen-free medium containing (in grams per liter): MgSO4, 0.2; CaCl2, 0.02; KH2PO4, 1; K2HPO4, 1; FeCl3, 0.05. The pH was adjusted to 7.5, and the medium was then autoclaved. After sterilization the medium was amended with a sterile glucose solution to give a final concentration of 0.1% (wt/vol) and shale oil to give a concentration of 1% (wt/vol). The shale oil was thus the sole source of nitrogen but not the sole source of carbon for these enrichments. The enrichments were incubated at 28°C on a rotary shaker at 200 rpm. The enrichment cultures have been maintained by monthly transfers into fresh medium.

Duration of test (contact time):

45 d

Initial conc.:

1 000 mg/L

Based on:

test mat.

Remarks:

(0.1%)

Parameter followed for biodegradation estimation:

test mat. analysis

Details on study design:

TEST CONDITIONS
- Composition of medium: Nitrogen free medium was used as a test medium for the study.
- Test temperature: 28°C
- pH: 7.5
- pH adjusted: Yes

CONTROL AND BLANK SYSTEM
Controls containing shale oil and 100 ml of sterile mineral medium were incubated under identical conditions. The controls served to account for any substrate loss due to volatilization or other non-biological loss.

Key result

Parameter:

% degradation (test mat. analysis)

Value:

100

Sampling time:

3 d

Remarks on result:

other: Other details not known

Details on results:

After 3 days of incubation of the strain of P. fluorescens with the test chemical Undecyl cyanide, as the sole source of carbon and nitrogen, the Undecyl cyanide could no longer be detected (i.e test chemical undergoes 100% degradation).

TABLE: Removal of nitriles from Stuart shale oil during incubation with a nitrile-degrading enrichment culture.

 

Nitrile	% Nitrile removal at incubation time (days:
	1	3	7	14	28	45
n—C12	0	100	100	100	100	100

Validity criteria fulfilled:

not specified

Interpretation of results:

readily biodegradable

Conclusions:

The percentage degradation of test substance Dodecanenitrile was determined to be 100% after a period of 3 days. Thus, based on percentage degradation, Dodecanenitrile is considered to be readily biodegradable in water.

Executive summary:

Biodegradation study was conducted for 45 days for evaluating the percentage biodegradability of test substance Dodecanenitrile (CAS no. 2437-25-4) under aerobic conditions at a temperature of 28°C and pH of 7.5, respectively. A bacterial strain Pseudomonas fluorescens was used as a test inoculum isolated from the undecanenitrile broth platings and identified by using Rapid NFT Strips (API Systems S.A.) and also isolated directly from the original enrichment culture by plating onto 0.1 strength Trypticase soy broth (BBL Microbiology Systems) solidified with purified agar (Difco). It was identified as a strain of Pseudomonas aeruginosa by using the Rapid NFT Strips.Pseudomonas fluorescens strain was grown in nitrogen-free medium with 0.1% glucose and 1% shale oil (identical conditions as the parent enrichment culture with the shale oil as the sole nitrogen but not the sole carbon source) or Bushnell-Haas medium with 0.3% shale oil (shale oil as the sole carbon but not the sole nitrogen source). Several soil sources contaminated with petroleum, including soils from oily-sludge land farming and drill cores, were used as sources of inocula for enrichment cultures.Ten grams of each soil was added to 100 ml of a nitrogen-free medium containing (in grams per liter): MgSO4, 0.2; CaCl2, 0.02; KH2PO4, 1; K2HPO4, 1; FeCl3, 0.05. The pH was adjusted to 7.5, and the medium was then autoclaved. After sterilization the medium was amended with a sterile glucose solution to give a final concentration of 0.1% (wt/vol) and shale oil to give a concentration of 1% (wt/vol).Theshale oil was thus the sole source of nitrogen but not the sole source of carbon for these enrichments.The enrichments were incubated at 28°C on a rotary shaker at 200 rpm. The enrichment cultures have been maintained by monthly transfers into fresh medium. Initial test substance concentration used for the study was1000 mg/l.After 7 days of incubation with the aliphatic nitriles as substrates, hexamethylbenzene (HMB) was added as an internal standard, and the nitriles were recovered from the broth by extraction with methylene chloride.The ability of bacterium to utilize these individual nitriles as sole nitrogen and carbon sources was determined by gas-liquid chromatography with a flame ionization detector and the chromatographic conditions.The percentage degradation of test substance Dodecanenitrile was determined to be 100% after a period of 3 days. Thus, based on percentage degradation, Dodecanenitrile is considered to be readily biodegradable in nature.

Description of key information

The percentage degradation of test substance Dodecanenitrile was determined to be 100% after a period of 3 days.  Thus, based on percentage degradation, Dodecanenitrile is considered to be readily biodegradable in water.

Key value for chemical safety assessment

Biodegradation in water:

readily biodegradable

Additional information

Various experimental studies and predicted data for the target compound Dodecanenitrile (CAS No. 2437-25-4) and supporting studies for its read across substance were reviewed for the biodegradation end point which are summarized as below:

 

In an experimental key study from peer reviewed journal (Jackie Aislabie et. al; 1988), biodegradation experiment was conducted for 45 days for evaluating the percentage biodegradability of test substance Dodecanenitrile (CAS no. 2437-25-4) under aerobic conditions at a temperature of 28°C and pH of 7.5, respectively. A bacterial strain Pseudomonas fluorescens was used as a test inoculum isolated from the undecanenitrile broth platings and identified by using Rapid NFT Strips (API Systems S.A.) and also isolated directly from the original enrichment culture by plating onto 0.1 strength Trypticase soy broth (BBL Microbiology Systems) solidified with purified agar (Difco). It was identified as a strain of Pseudomonas aeruginosa by using the Rapid NFT Strips.Pseudomonas fluorescens strain was grown in nitrogen-free medium with 0.1% glucose and 1% shale oil (identical conditions as the parent enrichment culture with the shale oil as the sole nitrogen but not the sole carbon source) or Bushnell-Haas medium with 0.3% shale oil (shale oil as the sole carbon but not the sole nitrogen source). Several soil sources contaminated with petroleum, including soils from oily-sludge land farming and drill cores, were used as sources of inocula for enrichment cultures.Ten grams of each soil was added to 100 ml of a nitrogen-free medium containing (in grams per liter): MgSO4, 0.2; CaCl2, 0.02; KH2PO4, 1; K2HPO4, 1; FeCl3, 0.05. The pH was adjusted to 7.5, and the medium was then autoclaved. After sterilization the medium was amended with a sterile glucose solution to give a final concentration of 0.1% (wt/vol) and shale oil to give a concentration of 1% (wt/vol).Theshale oil was thus the sole source of nitrogen but not the sole source of carbon for these enrichments.The enrichments were incubated at 28°C on a rotary shaker at 200 rpm. The enrichment cultures have been maintained by monthly transfers into fresh medium. Initial test substance concentration used for the study was1000 mg/l.After 7 days of incubation with the aliphatic nitriles as substrates, hexamethylbenzene (HMB) was added as an internal standard, and the nitriles were recovered from the broth by extraction with methylene chloride.The ability of bacterium to utilize these individual nitriles as sole nitrogen and carbon sources was determined by gas-liquid chromatography with a flame ionization detector and the chromatographic conditions.The percentage degradation of test substance Dodecanenitrile was determined to be 100% after a period of 3 days. Thus, based on percentage degradation, Dodecanenitrile is considered to be readily biodegradable in nature.

 

Another biodegradation study was conducted for 28 days for evaluating the percentage biodegradability of test substance Dodecanenitrile (CAS no. 2437-25-4) (from secondary source U.S. Environmental Protection Agency, 2012 and HPVIS, 2017). The study was performed according to OECD Guideline 301 C (Ready Biodegradability: Modified MITI Test (I)) under aerobic conditions. Activated sludge, domestic was used as a test inoculum for the study. The percentage degradation of test substance Dodecanenitrile was determined to be15% by ThOD parameter in 28 days. Thus, based on percentage degradation, Dodecanenitrile is considered to be not readily biodegradable in nature.

 

In a prediction using the Estimation Programs Interface Suite (EPI suite, 2017), the biodegradation potential of the test compound Dodecanenitrile (CAS no. 2437 -25 -4) in the presence of mixed populations of environmental microorganisms was estimated. The biodegradability of the substance was calculated using seven different models such as Linear Model, Non-Linear Model, Ultimate Biodegradation Timeframe, Primary Biodegradation Timeframe, MITI Linear Model, MITI Non-Linear Model and Anaerobic Model (called as Biowin 1-7, respectively) of the BIOWIN v4.10 software. The results indicate that chemical Dodecanenitrile is expected to be readily biodegradable.  

 

For the read across substance Nonanenitrile (CAS no. 2243-27-8) from authoritative database (J-CHECK, 2017 and EnviChem, 2014), biodegradation study was conducted for 28 days for evaluating the percentage biodegradability of read across substance Nonanenitrile (CAS no. 2243-27-8). The study was performed according to OECD Guideline 301 C (Ready Biodegradability: Modified MITI Test (I)). Concentration of inoculum i.e, sludge used was 30 mg/l and initial test substance conc. used in the study was 100 mg/l, respectively. The percentage degradation of read across substance Nonanenitrile was determined to be 69, 83 and 100% by BOD, TOC removal and GC parameter in 28 days. Thus, based on percentage degradation, Nonanenitrile is considered to be readily biodegradable in nature.

In a supporting study from peer reviewed journal (Jackie Aislabie et. al; 1988) for read across substance Undecanenitrile (CAS no. 2244-07-7), biodegradation experiment was conducted for 45 days for evaluating the percentage biodegradability of read across substance Undecanenitrile under aerobic conditions at a temperature of 28°C and pH of 7.5, respectively. A bacterial strain Pseudomonas fluorescens was used as a test inoculum isolated from the undecanenitrile broth platings and identified by using Rapid NFT Strips (API Systems S.A.) and also isolated directly from the original enrichment culture by plating onto 0.1 strength Trypticase soy broth (BBL Microbiology Systems) solidified with purified agar (Difco). It was identified as a strain of Pseudomonas aeruginosa by using the Rapid NFT Strips.Pseudomonas fluorescens strain was grown in nitrogen-free medium with 0.1% glucose and 1% shale oil (identical conditions as the parent enrichment culture with the shale oil as the sole nitrogen but not the sole carbon source) or Bushnell-Haas medium with 0.3% shale oil (shale oil as the sole carbon but not the sole nitrogen source). Several soil sources contaminated with petroleum, including soils from oily-sludge land farming and drill cores, were used as sources of inocula for enrichment cultures.Ten grams of each soil was added to 100 ml of a nitrogen-free medium containing (in grams per liter): MgSO4, 0.2; CaCl2, 0.02; KH2PO4, 1; K2HPO4, 1; FeCl3, 0.05. The pH was adjusted to 7.5, and the medium was then autoclaved. After sterilization the medium was amended with a sterile glucose solution to give a final concentration of 0.1% (wt/vol) and shale oil to give a concentration of 1% (wt/vol).The shale oil was thus the sole source of nitrogen but not the sole source of carbon for these enrichments.The enrichments were incubated at 28°C on a rotary shaker at 200 rpm. The enrichment cultures have been maintained by monthly transfers into fresh medium. Initial test substance concentration used for the study was 1000 mg/l.After 7 days of incubation with the aliphatic nitriles as substrates, hexamethylbenzene (HMB) was added as an internal standard, and the nitriles were recovered from the broth by extraction with methylene chloride.The ability of bacterium to utilize these individual nitriles as sole nitrogen and carbon sources was determined by gas-liquid chromatography with a flame ionization detector and the chromatographic conditions. The percentage degradation of read across substance Undecanenitrile was determined to be100% after a period of 3 days. Thus, based on percentage degradation, Undecanenitrile is considered to be readily biodegradable in nature.

 

On the basis of overall results for target chemical Dodecanenitrile (from peer reviewed journal, secondary source and EPI suite, 2017) and for its read across substance (from authoritative database J-CHECK, EnviChem and peer reviewed journal), it can be concluded that the test substance Dodecanenitrile can be expected to be readily biodegradable in nature.