Hydrocarbons, C10-C13, n-alkanes, isoalkanes, cyclics, < 2% aromatics

Biodegradation in water: screening tests

Link to relevant study record(s)

Reference

Reference 1

Endpoint:

biodegradation in water: ready biodegradability

Type of information:

experimental study

Adequacy of study:

key study

Study period:

March to April 1993

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: The study was conducted according to a standard guideline, but it was not conducted under GLP guidelines and oxygen consumption was not reported.

Justification for type of information:

A discussion and report on the read across strategy is given as an attachment in IUCLID Section 13.

Reason / purpose for cross-reference:

read-across: supporting information

Qualifier:

according to guideline

Guideline:

EPA OTS 796.3100 (Aerobic Aquatic Biodegradation)

Deviations:

yes

Remarks:

The test was conducted without a negative control, but this does not invalidate the results.

GLP compliance:

no

Oxygen conditions:

aerobic

Inoculum or test system:

activated sludge, non-adapted

Duration of test (contact time):

31 d

Initial conc.:

>= 22.97 - <= 23.35 mg/L

Based on:

test mat.

Parameter followed for biodegradation estimation:

CO2 evolution

Reference substance:

benzoic acid, sodium salt

Parameter:

% degradation (CO2 evolution)

Value:

0

Sampling time:

3 d

Parameter:

% degradation (CO2 evolution)

Value:

2.47

Sampling time:

8 d

Parameter:

% degradation (CO2 evolution)

Value:

5.44

Sampling time:

16 d

Parameter:

% degradation (CO2 evolution)

Value:

7.34

Sampling time:

24 d

Parameter:

% degradation (CO2 evolution)

Value:

8.74

Sampling time:

31 d

Details on results:

The positive control, sodium benzoate, biodegraded to 60.15% on day 16, 63.62% on day 24, and 65.70% on day 31.

Validity criteria fulfilled:

yes

Remarks:

The test was conducted without a negative control, but this does not invalidate the results.

Interpretation of results:

not inherently biodegradable

Conclusions:

The test substance biodegraded to an extent of 7.34% after 24 days and 8.74% after 31 days. The test substance is not inherently biodegradable.

Executive summary:

The test substance biodegraded to an extent of 7.34% after 24 days and 8.74% after 31 days. The test substance is not inherently biodegradable.

Reference 2

Endpoint:

biodegradation in water: ready biodegradability

Type of information:

experimental study

Adequacy of study:

key study

Study period:

May to August 1996

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: The study was conducted according to a standard guideline without deviations from the protocol, but it was not conducted under GLP guidelines and oxygen consumption was not reported.

Justification for type of information:

A discussion and report on the read across strategy is given as an attachment in IUCLID Section 13.

Reason / purpose for cross-reference:

read-across: supporting information

Qualifier:

equivalent or similar to guideline

Guideline:

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

Deviations:

no

Principles of method if other than guideline:

The test included two consecutive 41-day phases. The first phase of the test was conducted following the OECD Guideline 301 F (Ready Biodegradability Test) and using a non acclimated, domestic, sewage sludge inoculum, but extending the duration to 41 days. The second phase of the test was conducted following the OECD Guideline 301 F (Ready Biodegradability Test), and using the day 41 acclimated inoculum from the first phase of the test, with a duration of another 41 days.

GLP compliance:

no

Oxygen conditions:

aerobic

Inoculum or test system:

other: Activated sludge, domestic, non-adapted was used in the non acclimated phase of the test. The acclimated phase of the test used the inoculum collected from the non acclimated test phase at its termination.

Details on inoculum:

The non acclimated activated sludge inoculum used in this study was obtained from a domestic wastewater treatment plant, in New Jersey, USA.

Duration of test (contact time):

82 d

Initial conc.:

ca. 48 - <= 60 mg/L

Based on:

test mat.

Parameter followed for biodegradation estimation:

O2 consumption

Details on study design:

Quadruplicate test systems were used to evaluate the biodegradability of the test substance at a concentration range of 48 to 60 mg/L. Duplicate test systems were used to evaluate the positive control substance at approximate concentrations of 51 mg/L. Blank test systems, which did not contain the test or positive control substance, were run concurrently.

Reference substance:

benzoic acid, sodium salt

Preliminary study:

A preliminary study was not conducted.

Parameter:

% degradation (O2 consumption)

Value:

31.3

St. dev.:

2.5

Sampling time:

28 d

Remarks on result:

other: From the non acclimated test

Parameter:

% degradation (O2 consumption)

Value:

40.5

St. dev.:

2.8

Sampling time:

41 d

Remarks on result:

other: From the non acclimated test

Parameter:

% degradation (O2 consumption)

Value:

41.7

St. dev.:

3.1

Sampling time:

28 d

Remarks on result:

other: From the acclimated test

Parameter:

% degradation (O2 consumption)

Value:

47.5

St. dev.:

1.4

Sampling time:

41 d

Remarks on result:

other: From the acclimated test

Details on results:

The test material was not readily biodegradable. The test material reached 10% biodegradation on day 13 of the non acclimated test phase and on day 7 of the acclimated test phase. A half-life was not determined. By Day 41, the average percent biodegradation of quadruplicate test systems was 41% in the non acclimated test and 48% in the acclimated test.

Biodegradation was based on oxygen consumption and the theoretical oxygen demand of the test substance was calculated using results of an elemental analysis of the test substance.

Interval results for the test substance are as follows:

Day % Degradation % Degradation
Non Acclimated Test Acclimated Test
(mean of quadruplicate systems) (mean of quadruplicate systems)

3 0.24 0.35
7 0.53 13.1
13 10.6 25.9
18 19.4 32.7
25 28.3 39.5
28 31.3 41.7
41 40.5 47.5

Results with reference substance:

The reference substance biodegraded to an extent of 89% in the non acclimated test and 87% in the acclimated test after 28 days. By Day 3, >60% biodegradation of the positive control was observed in both tests, which meets the guideline requirement.

Validity criteria fulfilled:

yes

Remarks:

The test guideline validity criteria require that the oxygen uptake in the inoculum blank should not exceed 60 mg/L in 28 days, which it did not, therefore, the results are considered valid. These data were contained in the laboratory notebook.

Interpretation of results:

inherently biodegradable

Conclusions:

The test substance biodegraded to an extent of 31% after 28 days and 41% after 41 days during a non acclimated phase of the test. The test substance biodegraded to an extent of 42% after 28 days and 48% after 41 days during an acclimated phase of the test.

Executive summary:

The test substance biodegraded to an extent of 31% after 28 days and 41% after 41 days during a non acclimated phase of the test. The test substance biodegraded to an extent of 42% after 28 days and 48% after 41 days during an acclimated phase of the test. The test substance can be characterized as inherently biodegradable.

Reference 3

Endpoint:

biodegradation in water: ready biodegradability

Type of information:

experimental study

Adequacy of study:

key study

Study period:

July 2008

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: The study was conducted according to a standard guideline and was conducted with minor deviations, but was not conducted under a GLP guideline.

Justification for type of information:

A discussion and report on the read across strategy is given as an attachment in IUCLID Section 13.

Reason / purpose for cross-reference:

read-across: supporting information

Qualifier:

according to guideline

Guideline:

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

Deviations:

yes

Remarks:

Reduced concentration of test substance, 100 mg to 50 mg; reduced pH to improve efficiency of CO2 removal, 7.4 to 7.0; used a surfactant to disperse test material

GLP compliance:

yes

Oxygen conditions:

aerobic

Inoculum or test system:

activated sludge, domestic, non-adapted

Details on inoculum:

The inoculum for was derived from the recycled sludge of the City of Lake Charles, Louisiana Domestic Waste Water Plant A. The sludge was aerated for 7-days prior to use. The inoculum in the test medium was adjusted to a final concentration of 10 mg/L of total suspended solids (TSS) which meets the guideline specification of <30 mg/L TSS.

Duration of test (contact time):

28 d

Initial conc.:

50 mg/L

Based on:

ThOD/L

Parameter followed for biodegradation estimation:

O2 consumption

Details on study design:

Approximately 500 mg of silica gel (Aldrich, Merck grade 9385) with a mesh size of 230-400 ¿, was weighed out in a mound onto a creased piece of weighing paper. A spatula was then used to tap the top of the mound and flatten it so that it became a thick ¿plateau¿. This prevented drops of the sample material from rolling off of the silica gel when applied. A 1 mL syringe was then held vertically and individual drops of sample material were dispensed on to the silica gel until a weight close to 50 mg was reached. The actual weight of the sample material was then recorded. Special care was taken to ensure that two drops were not placed on top of each other so that none of the sample material soaked down to the weighing paper. The weighing paper was then rolled into a cone and the sample material dispersed on silica gel was poured into a 125 mm X 15 mm test tube. The silica gel/test substance mixture was mixed using a VWR Scientific Products, Mini Vortexer MV1, set at highest speed (2500 rpm) for five minutes. This uniformly dispersed the test substance over the silica gel with no visual signs of test substance residue on the test tube walls.

A surfactant was added to the silica gel/sample mixture to aid in the dispersion stability and to keep the micro-size droplets of the test substance from coalescing into large droplets. The surfactant was a C12-15 Fischer Tropsch alcohol 3 mole EO ether sulfate made with a catalyst that gives a peaked distribution of the ethoxymers. The final concentration of the surfactant was 5 mg active/L.

The 1-liter test vessels containing 900 mL of inoculated medium were placed on a magnetic stirrer and mixed prior to receiving the contents from the test tubes. Each flask contained a stir bar which was positioned over a magnetic stirrer to provide vigorous mixing during the test. The silica gel dispersed samples were then poured into the test vessels. A uniform dispersion of the sample material was immediately observed in all units. The 1-liter vessels were then placed in the water bath (22±1°C) of the electrolytic respirometer units. The instrument underwent a 60 minute initialization/equalization before data collection began. CO2 generation and O2 uptake data were recorded by the instrument every six hours during the 28-day test. Blanks were also included in the study for validity purposes. These blanks were prepared identical to those vessels with the samples except that they did not contain the test substance (i.e. blanks contained inoculum, silica gel, and surfactant only).

Reference substance:

benzoic acid, sodium salt

Preliminary study:

A preliminary study was not conducted.

Test performance:

Slight deviations were made to the OECD 301F guidelines to better accommodate the poorly water-soluble test substance. The modifications employed were as follows: (1) reduction in concentration of test substance from 100 mg to 50 mg, (2) reduction of the pH from 7.4 to 7.0 to improve the efficiency of CO2 removal, and (3) the use of a surfactant for dispersing the test material.

Parameter:

% degradation (O2 consumption)

Value:

7.3

Sampling time:

4 d

Parameter:

% degradation (O2 consumption)

Value:

16.2

Sampling time:

5 d

Parameter:

% degradation (O2 consumption)

Value:

50.4

Sampling time:

13 d

Parameter:

% degradation (O2 consumption)

Value:

60.02

Sampling time:

16 d

Parameter:

% degradation (O2 consumption)

Value:

89.8

Sampling time:

28 d

Details on results:

The test substance exhibited rapid biodegradation and assessed as readily biodegradable. The half-life was approximately 13 days. By Day 28, the average percent biodegradation of the test substance was 89.8%. The test substance reached 10% biodegradation on approximately Day 5 and 60% biodegradation on Day 16.

Biodegradation was based on oxygen consumption and the theoretical oxygen demand of the test substance was calculated using results of an elemental analysis of the test substance.

Results with reference substance:

The reference substance biodegraded to an extent of 87% after 28 days. By Day 6, >60% biodegradation of the positive control was observed, which meets the guideline requirement.

Validity criteria fulfilled:

yes

Interpretation of results:

readily biodegradable

Conclusions:

Hydrocarbons, C10-C13, isoalkanes, cyclics, <2% aromatics, biodegraded 89.8% after 28 days under the conditions of the study and is readily biodegradable.

Executive summary:

Hydrocarbons, C10-C13, isoalkanes, cyclics, <2% aromatics, biodegraded to an extent of 89.8% after 28 days. The data support characterizing the test substance as rapidly biodegradable, readily biodegradable, not expected to persist in the environment under aerobic conditions. Although it did not meet the 10 -day window requirement, it is characterized as readily biodegradable because the criterium is not applied to multi-component substances when assessing their ready biodegradability.

Reference 4

Endpoint:

biodegradation in water: ready biodegradability

Type of information:

experimental study

Adequacy of study:

key study

Study period:

March to April 1993

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: The study was conducted according to a standard guideline, but it was not conducted under GLP guidelines and oxygen consumption was not reported.

Justification for type of information:

A discussion and report on the read across strategy is given as an attachment in IUCLID Section 13.

Reason / purpose for cross-reference:

read-across: supporting information

Qualifier:

according to guideline

Guideline:

EPA OTS 796.3100 (Aerobic Aquatic Biodegradation)

Deviations:

yes

Remarks:

The test was conducted without a negative control, but this does not invalidate the results.

GLP compliance:

no

Oxygen conditions:

aerobic

Inoculum or test system:

activated sludge, non-adapted

Duration of test (contact time):

31 d

Initial conc.:

>= 22.55 - <= 23.45 mg/L

Based on:

test mat.

Parameter followed for biodegradation estimation:

CO2 evolution

Reference substance:

benzoic acid, sodium salt

Parameter:

% degradation (CO2 evolution)

Value:

1.74

Sampling time:

3 d

Parameter:

% degradation (CO2 evolution)

Value:

5.66

Sampling time:

8 d

Parameter:

% degradation (CO2 evolution)

Value:

13.63

Sampling time:

16 d

Parameter:

% degradation (CO2 evolution)

Value:

16.07

Sampling time:

24 d

Parameter:

% degradation (CO2 evolution)

Value:

18.39

Sampling time:

31 d

Details on results:

The positive control, sodium benzoate, biodegraded to 60.15% on day 16, 63.62% on day 24, and 65.70% on day 31.

Validity criteria fulfilled:

yes

Remarks:

The test was conducted without a negative control, but this does not invalidate the results.

Interpretation of results:

not inherently biodegradable

Conclusions:

The test substance biodegraded to an extent of 16.07% after 24 days and 18.39% after 31 days. The test substance is not inherently biodegradable.

Executive summary:

The test substance biodegraded to an extent of 16.07% after 24 days and 18.39% after 31 days. The test substance is not inherently biodegradable.

Reference 5

Endpoint:

biodegradation in water: ready biodegradability

Type of information:

experimental study

Adequacy of study:

key study

Study period:

February to March 1995

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: The study was conducted according to a standard guideline without deviations from the protocol and conducted under GLP guidelines.

Justification for type of information:

A discussion and report on the read across strategy is given as an attachment in IUCLID Section 13.

Reason / purpose for cross-reference:

read-across: supporting information

Qualifier:

according to guideline

Guideline:

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

Deviations:

no

GLP compliance:

yes

Oxygen conditions:

aerobic

Inoculum or test system:

activated sludge, domestic, non-adapted

Duration of test (contact time):

30 d

Initial conc.:

37 mg/L

Based on:

test mat.

Parameter followed for biodegradation estimation:

O2 consumption

Details on study design:

Duplicate test systems were used to evaluate the biodegradability of the test substance at a concentration of 37 mg/L. One test system was used to evaluate the positive control substance at a concentration of approximately 31 mg/L. Duplicate blank test systems, which did not contain the test or positive control substance, were run concurrently.

Reference substance:

benzoic acid, sodium salt

Preliminary study:

A preliminary study was not conducted.

Parameter:

% degradation (O2 consumption)

Value:

ca. 10

Sampling time:

3 d

Parameter:

% degradation (O2 consumption)

Value:

ca. 50

Sampling time:

9 d

Parameter:

% degradation (O2 consumption)

Value:

61.3

Sampling time:

12 d

Parameter:

% degradation (O2 consumption)

Value:

76.6

Sampling time:

28 d

Remarks on result:

other: Percent biodegradation was still increasing.

Parameter:

% degradation (O2 consumption)

Value:

76.6

Sampling time:

30 d

Details on results:

The test substance exhibited rapid biodegradation, and was assessed as readily biodegradable. The half-life was approximately 9 days. By Day 30, the average percent biodegradation of the test substance was 76.6%. The test substance reached 10% biodegradation on Day 3, and approximately 60% biodegradation on Day 12.

Biodegradation was based on oxygen consumption and the theoretical oxygen demand of the test substance was calculated using results of an elemental analysis of the test substance.

Results with reference substance:

The reference substance biodegraded to an extent of 88% after 28 days. By Day 5, >60% biodegradation of the positive control was observed, which meets the guideline requirement.

Validity criteria fulfilled:

yes

Remarks:

The test guideline validity criteria require that the oxygen uptake in the inoculum blank should not exceed 60 mg/L in 28 days, which it did not, therefore, the results are considered valid.

Interpretation of results:

readily biodegradable

Conclusions:

The test substance biodegraded to an extent of approximately 77% after 28 days. The data support characterizing the test material as rapidly biodegradable (readily biodegradable).

Executive summary:

The test substance biodegraded to an extent of approximately 77% after 28 days. The data support characterizing the test material as rapidly biodegradable (readily biodegradable).

Reference 6

Endpoint:

biodegradation in water: ready biodegradability

Type of information:

experimental study

Adequacy of study:

key study

Study period:

March to April 1993

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: The study was conducted according to a standard guideline, but it was not conducted under GLP guidelines and oxygen consumption was not reported.

Justification for type of information:

A discussion and report on the read across strategy is given as an attachment in IUCLID Section 13.

Reason / purpose for cross-reference:

read-across: supporting information

Qualifier:

according to guideline

Guideline:

EPA OTS 796.3100 (Aerobic Aquatic Biodegradation)

Deviations:

yes

Remarks:

The test was conducted without a negative control, but this does not invalidate the results.

GLP compliance:

no

Oxygen conditions:

aerobic

Inoculum or test system:

activated sludge, non-adapted

Duration of test (contact time):

31 d

Initial conc.:

>= 23.3 - <= 23.98 mg/L

Based on:

test mat.

Parameter followed for biodegradation estimation:

CO2 evolution

Reference substance:

benzoic acid, sodium salt

Parameter:

% degradation (CO2 evolution)

Value:

5.03

Sampling time:

3 d

Parameter:

% degradation (CO2 evolution)

Value:

8.69

Sampling time:

8 d

Parameter:

% degradation (CO2 evolution)

Value:

11.69

Sampling time:

16 d

Parameter:

% degradation (CO2 evolution)

Value:

12.69

Sampling time:

24 d

Parameter:

% degradation (CO2 evolution)

Value:

13.69

Sampling time:

31 d

Details on results:

The positive control, sodium benzoate, biodegraded to 60.15% on day 16, 63.62% on day 24, and 65.70% on day 31.

Validity criteria fulfilled:

yes

Remarks:

The test was conducted without a negative control, but this does not invalidate the results.

Interpretation of results:

not inherently biodegradable

Conclusions:

The test substance biodegraded to an extent of 12.69% after 24 days and 13.69% after 31 days. The test substance is not inherently biodegradable.

Executive summary:

The test substance biodegraded to an extent of 12.69% after 24 days and 13.69% after 31 days. The test substance is not inherently biodegradable.

Reference 7

Endpoint:

biodegradation in water: ready biodegradability

Type of information:

experimental study

Adequacy of study:

key study

Study period:

August to September 1994

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: The study was conducted according to a standard guideline without deviations from the protocol and was conducted under GLP guidelines.

Justification for type of information:

A discussion and report on the read across strategy is given as an attachment in IUCLID Section 13.

Reason / purpose for cross-reference:

read-across: supporting information

Qualifier:

according to guideline

Guideline:

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

Deviations:

no

GLP compliance:

yes

Oxygen conditions:

aerobic

Inoculum or test system:

activated sludge, domestic, non-adapted

Details on inoculum:

An un-acclimated activated sludge inoculum was used in this study. The inoculum was obtained from the Somerset Raritan Valley Sewage Authority, Bridgewater, New Jersey, USA. The treatment plant receives predominantly domestic sewage. The sewage sample was obtained one day prior to test initiation. The microbial count was 106 CFU/mL. The sludge supernatant was added at a 1% loading volume of to test medium. Test medium consisted of glass distilled water and mineral salts (phosphate buffer, ferric chloride, magnesium sulfate, calcium chloride). One liter of test medium and activated sludge, which was aerated for 24 hours with carbon dioxide free air, was added to each one liter respirometer flask.

Duration of test (contact time):

28 d

Initial conc.:

ca. 38 mg/L

Based on:

test mat.

Parameter followed for biodegradation estimation:

O2 consumption

Details on study design:

Triplicate test systems were used to evaluate the biodegradability of the test substance and the positive control substance at mean concentrations of approximately 38 mg/L and 50 mg/L, respectively. Blank test systems, which did not contain the test or positive control substance, were run concurrently in triplicate. The test substance was weighed in an air tight syringe and injected into the test medium. The test system was sealed immediately after addition of the test substance. An aliquot of the positive control stock solution was added to the appropriate test flasks. All test vessels were stirred constantly using magnetic stir bars and plates. The study was conducted at a temperature of 21°C.

Reference substance:

benzoic acid, sodium salt

Preliminary study:

A preliminary study was not conducted.

Test performance:

No deviations from the protocol occurred that affected the integrity of the study data.

Parameter:

% degradation (O2 consumption)

Value:

4.8

Sampling time:

2 d

Parameter:

% degradation (O2 consumption)

Value:

12.7

Sampling time:

3 d

Parameter:

% degradation (O2 consumption)

Value:

53

Sampling time:

12 d

Parameter:

% degradation (O2 consumption)

Value:

60.2

Sampling time:

18 d

Parameter:

% degradation (O2 consumption)

Value:

67.6

Sampling time:

28 d

Remarks on result:

other: Percent biodegradation was still increasing.

Details on results:

The test substance exhibited rapid biodegradation, and assessed as readily biodegradable. The half-life was approximately 12 days. By Day 31, the average percent biodegradation of the test substance was 68.7%. The test substance reached 10% biodegradation on approximately Day 3 and 60% biodegradation on approximately Day 18.

Biodegradation was based on oxygen consumption and the theoretical oxygen demand of the test substance was calculated using results of an elemental analysis of the test substance.

Results with reference substance:

The reference substance biodegraded to an extent of 88.7% after 28 days. By Day 3, >60% biodegradation of the positive control was observed, which meets the guideline requirement.

Validity criteria fulfilled:

yes

Interpretation of results:

readily biodegradable, but failing 10-day window

Conclusions:

The test substance, a multi-component substance, biodegraded to an extent of 68% after 28 days and 69% after 31 days. The data support characterizing the test substance as rapidly biodegradable, readily biodegradable, not expected to persist in the environment under aerobic conditions. Although it did not meet the 10-day window requirement, it is characterized as readily biodegradable because the criterium is not applied to multi-component substances when assessing their ready biodegradability.

Executive summary:

The test substance, a multi-component substance, biodegraded to an extent of 68% after 28 days and 69% after 31 days. The data support characterizing the test substance as rapidly biodegradable, readily biodegradable, not expected to persist in the environment under aerobic conditions. Although it did not meet the 10-day window requirement, it is characterized as readily biodegradable because the criterium is not applied to multi-component substances when assessing their ready biodegradability.

Reference 8

Endpoint:

biodegradation in water: ready biodegradability

Type of information:

experimental study

Adequacy of study:

key study

Study period:

July to August 1994

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: The study was conducted according to a standard guideline without deviations from the protocol and conducted under GLP guidelines.

Justification for type of information:

A discussion and report on the read across strategy is given as an attachment in IUCLID Section 13.

Reason / purpose for cross-reference:

read-across: supporting information

Qualifier:

according to guideline

Guideline:

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

Deviations:

no

GLP compliance:

yes

Oxygen conditions:

aerobic

Inoculum or test system:

activated sludge, domestic, non-adapted

Duration of test (contact time):

38 d

Initial conc.:

49.4 mg/L

Based on:

other: test mat., replicate 1

Initial conc.:

32 mg/L

Based on:

other: test mat., replicate 2

Parameter followed for biodegradation estimation:

O2 consumption

Details on study design:

Duplicate test systems were used to evaluate the biodegradability of the test substance at a concentration of 49.4 mg/L. One test system was used to evaluate the positive control substance at a concentration of 40.6 mg/L. Duplicate blank test systems, which did not contain the test or positive control substance, were run concurrently.

Reference substance:

benzoic acid, sodium salt

Preliminary study:

A preliminary study was not conducted.

Parameter:

% degradation (O2 consumption)

Value:

ca. 10

Sampling time:

2 d

Parameter:

% degradation (O2 consumption)

Value:

ca. 50

Sampling time:

8 d

Parameter:

% degradation (O2 consumption)

Value:

ca. 63

Sampling time:

12 d

Parameter:

% degradation (O2 consumption)

Value:

ca. 79

Sampling time:

28 d

Parameter:

% degradation (O2 consumption)

Value:

79

Sampling time:

38 d

Details on results:

The test substance exhibited rapid biodegradation, and was assessed as readily biodegradable. The half-life was approximately 8 days. By Day 38, the average percent biodegradation of the test substance was 79%. The test substance reached 10% biodegradation on Day 2, and approximately 60% biodegradation on Day 12.

Biodegradation was based on oxygen consumption and the theoretical oxygen demand of the test substance was calculated using results of an elemental analysis of the test substance.

Results with reference substance:

The reference substance biodegraded to an extent of approximately 90% after 28 days. By Day 4, >60% biodegradation of the positive control was observed, which meets the guideline requirement.

Validity criteria fulfilled:

yes

Remarks:

The test guideline validity criteria require that the oxygen uptake in the inoculum blank should not exceed 60 mg/L in 28 days, which it did not, therefore, the results are considered valid.

Interpretation of results:

readily biodegradable

Conclusions:

The test substance biodegraded to an extent of approximately 79% after 28 days. The data support characterizing the test material as rapidly biodegradable (readily biodegradable).

Executive summary:

The test substance biodegraded to an extent of approximately 79% after 28 days. The data support characterizing the test material as rapidly biodegradable (readily biodegradable).

Reference 9

Endpoint:

biodegradation in water: ready biodegradability

Type of information:

experimental study

Adequacy of study:

key study

Study period:

March to April 1993

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: The study was conducted according to a standard guideline, but it was not conducted under GLP guidelines and oxygen consumption was not reported.

Justification for type of information:

A discussion and report on the read across strategy is given as an attachment in IUCLID Section 13.

Reason / purpose for cross-reference:

read-across: supporting information

Qualifier:

according to guideline

Guideline:

EPA OTS 796.3100 (Aerobic Aquatic Biodegradation)

Deviations:

yes

Remarks:

The test was conducted without a negative control, but this does not invalidate the results.

GLP compliance:

no

Oxygen conditions:

aerobic

Inoculum or test system:

activated sludge, non-adapted

Duration of test (contact time):

31 d

Initial conc.:

>= 23.11 - <= 23.24 mg/L

Based on:

test mat.

Parameter followed for biodegradation estimation:

CO2 evolution

Reference substance:

benzoic acid, sodium salt

Parameter:

% degradation (CO2 evolution)

Value:

2.88

Sampling time:

3 d

Parameter:

% degradation (CO2 evolution)

Value:

7.37

Sampling time:

8 d

Parameter:

% degradation (CO2 evolution)

Value:

13.88

Sampling time:

16 d

Parameter:

% degradation (CO2 evolution)

Value:

16.95

Sampling time:

24 d

Parameter:

% degradation (CO2 evolution)

Value:

20.62

Sampling time:

31 d

Details on results:

The positive control, sodium benzoate, biodegraded to 60.15% on day 16, 63.62% on day 24, and 65.70% on day 31.

Validity criteria fulfilled:

yes

Remarks:

The test was conducted without a negative control, but this does not invalidate the results.

Interpretation of results:

not inherently biodegradable

Conclusions:

The test substance biodegraded to an extent of 16.95% after 24 days and 20.62% after 31 days. The test substance is not inherently biodegradable.

Executive summary:

The test substance biodegraded to an extent of 16.95% after 24 days and 20.62% after 31 days. The test substance is not inherently biodegradable.

Reference 10

Endpoint:

biodegradation in water: ready biodegradability

Type of information:

experimental study

Adequacy of study:

key study

Study period:

February to March 1996

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: The study was conducted according to a standard guideline without deviations from the protocol, but it was not conducted under GLP guidelines and oxygen consumption was not reported.

Justification for type of information:

A discussion and report on the read across strategy is given as an attachment in IUCLID Section 13.

Reason / purpose for cross-reference:

read-across: supporting information

Qualifier:

according to guideline

Guideline:

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

Deviations:

no

GLP compliance:

no

Oxygen conditions:

aerobic

Inoculum or test system:

activated sludge, domestic, non-adapted

Details on inoculum:

An un-acclimated activated sludge inoculum was used in this study. The inoculum was obtained from a domestic wastewater treatment plant, in New Jersey, USA.

Duration of test (contact time):

28 d

Initial conc.:

ca. 39 - <= 40 mg/L

Based on:

test mat.

Parameter followed for biodegradation estimation:

O2 consumption

Details on study design:

Triplicate test systems were used to evaluate the biodegradability of the test substance at concentrations of 39 to 40 mg/L. Duplicate test systems were used to evaluate the positive control substance at an approximate concentration of 51 mg/L. Blank test systems, which did not contain the test or positive control substance, were run concurrently.

Reference substance:

benzoic acid, sodium salt

Preliminary study:

A preliminary study was not conducted.

Parameter:

% degradation (O2 consumption)

Value:

7.1

St. dev.:

6.3

Sampling time:

6 d

Parameter:

% degradation (O2 consumption)

Value:

12.4

St. dev.:

8.2

Sampling time:

7 d

Parameter:

% degradation (O2 consumption)

Value:

47.8

St. dev.:

11

Sampling time:

24 d

Parameter:

% degradation (O2 consumption)

Value:

52.2

St. dev.:

9

Sampling time:

27 d

Parameter:

% degradation (O2 consumption)

Value:

53.4

St. dev.:

8.5

Sampling time:

28 d

Remarks on result:

other: Percent biodegradation was still increasing.

Details on results:

The test substance exhibited moderately rapid biodegradation, and assessed as inherently biodegradable. The half-life was approximately 27 days. By Day 28, the average percent biodegradation of the test substance was 53.4%. The test substance reached approximately 10% biodegradation on Day 7.

Biodegradation was based on oxygen consumption and the theoretical oxygen demand of the test substance was calculated using results of an elemental analysis of the test substance.

Results with reference substance:

The reference substance biodegraded to an extent of 94.2% (s.d. = 2.5) after 28 days. By Day 4, >60% biodegradation of the positive control was observed, which meets the guideline requirement.

Validity criteria fulfilled:

yes

Remarks:

The test guideline validity criteria require that the oxygen uptake in the inoculum blank should not exceed 60 mg/L in 28 days, which it did not, therefore, the results are considered valid. These data were contained in the laboratory notebook.

Interpretation of results:

inherently biodegradable

Conclusions:

The test substance biodegraded to an extent of 53% after 28 days. The data support characterizing the test material as exhibiting moderate rate of biodegradation (inherently biodegradable).

Executive summary:

The test substance biodegraded to an extent of 53% after 28 days. The data support characterizing the test material as exhibiting moderate rate of biodegradation (inherently biodegradable).

Reference 11

Endpoint:

biodegradation in water: ready biodegradability

Type of information:

experimental study

Adequacy of study:

key study

Study period:

July to August 1994

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: The study was conducted according to a standard guideline without deviations from the protocol and conducted under GLP guidelines.

Justification for type of information:

A discussion and report on the read across strategy is given as an attachment in IUCLID Section 13.

Reason / purpose for cross-reference:

read-across: supporting information

Qualifier:

according to guideline

Guideline:

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

Deviations:

no

GLP compliance:

yes

Oxygen conditions:

aerobic

Inoculum or test system:

activated sludge, domestic, non-adapted

Duration of test (contact time):

38 d

Initial conc.:

45 mg/L

Based on:

other: test mat., replicate 1

Initial conc.:

30.6 mg/L

Based on:

other: test mat., replicate 2

Parameter followed for biodegradation estimation:

O2 consumption

Details on study design:

Duplicate test systems were used to evaluate the biodegradability of the test substance at a concentration of 45 mg/L. One test system was used to evaluate the positive control substance at a concentration of approximately 40.6 mg/L. Duplicate blank test systems, which did not contain the test or positive control substance, were run concurrently.

Reference substance:

benzoic acid, sodium salt

Preliminary study:

A preliminary study was not conducted.

Parameter:

% degradation (O2 consumption)

Value:

27.8

Sampling time:

3 d

Parameter:

% degradation (O2 consumption)

Value:

ca. 50

Sampling time:

7 d

Parameter:

% degradation (O2 consumption)

Value:

60.7

Sampling time:

10 d

Parameter:

% degradation (O2 consumption)

Value:

ca. 80

Sampling time:

28 d

Remarks on result:

other: Percent biodegradation was still increasing.

Parameter:

% degradation (O2 consumption)

Value:

79.8

Sampling time:

38 d

Details on results:

The test substance exhibited rapid biodegradation, and was assessed as readily biodegradable. The half-life was approximately 7 days. By Day 38, the average percent biodegradation of the test substance was 79.8%. The test substance reached 10% biodegradation before Day 2, and approximately 60% biodegradation on Day 10.

Biodegradation was based on oxygen consumption and the theoretical oxygen demand of the test substance was calculated using results of an elemental analysis of the test substance.

Results with reference substance:

The reference substance biodegraded to an extent of 90% after 28 days. By Day 3, >60% biodegradation of the positive control was observed, which meets the guideline requirement.

Validity criteria fulfilled:

yes

Remarks:

The test guideline validity criteria require that the oxygen uptake in the inoculum blank should not exceed 60 mg/L in 28 days, which it did not, therefore, the results are considered valid.

Interpretation of results:

readily biodegradable

Conclusions:

The test substance biodegraded to an extent of approximately 80% after 28 days and 38 days. The data support characterizing the test material as rapidly biodegradable (readily biodegradable).

Executive summary:

The test substance biodegraded to an extent of approximately 80% after 28 days and 38 days. The data support characterizing the test material as rapidly biodegradable (readily biodegradable).

Reference 12

Endpoint:

biodegradation in water: ready biodegradability

Type of information:

experimental study

Adequacy of study:

key study

Study period:

August to September 1995

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: The study was conducted according to a standard guideline without deviations from the protocol, but it was not conducted under GLP guidelines and oxygen consumption was not reported.

Justification for type of information:

A discussion and report on the read across strategy is given as an attachment in IUCLID Section 13.

Reason / purpose for cross-reference:

read-across: supporting information

Qualifier:

according to guideline

Guideline:

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

Deviations:

no

GLP compliance:

no

Oxygen conditions:

aerobic

Inoculum or test system:

activated sludge, domestic, non-adapted

Details on inoculum:

An un-acclimated activated sludge inoculum was used in this study. The inoculum was obtained from a domestic wastewater treatment plant, in New Jersey, USA.

Duration of test (contact time):

28 d

Initial conc.:

ca. 45 mg/L

Based on:

test mat.

Parameter followed for biodegradation estimation:

O2 consumption

Details on study design:

Triplicate test systems were used to evaluate the biodegradability of the test substance at an approximate concentration of 45 mg/L. Duplicate test systems were used to evaluate the positive control substance at an approximate concentrations of 50 mg/L. Blank test systems, which did not contain the test or positive control substance, were run concurrently.

Reference substance:

benzoic acid, sodium salt

Preliminary study:

A preliminary study was not conducted.

Parameter:

% degradation (O2 consumption)

Value:

32.3

Sampling time:

3 d

Parameter:

% degradation (O2 consumption)

Value:

50.9

Sampling time:

5 d

Parameter:

% degradation (O2 consumption)

Value:

64.4

Sampling time:

10 d

Parameter:

% degradation (O2 consumption)

Value:

83.1

Sampling time:

28 d

Remarks on result:

other: Percent biodegradation was still increasing.

Parameter:

% degradation (O2 consumption)

Value:

85.5

Sampling time:

32 d

Details on results:

The test substance exhibited rapid biodegradation, and was assessed as readily biodegradable. The half-life was approximately 5 days. By Day 32, the average percent biodegradation of the test substance was 85.5%. The test substance reached 10% biodegradation before Day 3, the first data point, and approximately 60% biodegradation on Day 10.

Biodegradation was based on oxygen consumption and the theoretical oxygen demand of the test substance was calculated using results of an elemental analysis of the test substance.

Results with reference substance:

The reference substance biodegraded to an extent of 88.8% (s.d. = 0.1) after 28 days. By Day 3, >60% biodegradation of the positive control was observed, which meets the guideline requirement.

Validity criteria fulfilled:

yes

Remarks:

The test guideline validity criteria require that the oxygen uptake in the inoculum blank should not exceed 60 mg/L in 28 days, which it did not, therefore, the results are considered valid. These data were contained in the laboratory notebook.

Interpretation of results:

readily biodegradable

Conclusions:

The test substance biodegraded to an extent of 83% after 28 days and 86% after 32 days. The data support characterizing the test material as rapidly biodegradable (readily biodegradable).

Executive summary:

The test substance biodegraded to an extent of 83% after 28 days and 85% after 32 days. The data support characterizing the test substance as rapidly biodegradable (readily biodegradable).

Description of key information

Hydrocarbons, C9-C11, n-alkanes, isoalkanes, cyclics, <2% aromatics, biodegraded 80% after 28 days under the conditions of the study and is readily biodegradable.

Hydrocarbons, C9-C11, cyclics, <2% aromatics biodegraded to an extent of 53% after 28 days. The data support characterizing Hydrocarbons, C9-C11, cyclics, <2% aromatics as exhibiting moderate rate of biodegradation (inherently biodegradable).

A persistence (P) screening assessment has been realized for decane using EPI suite BIOWIN 2, 3 and 6 (v4.10) models, in accordance with Reach Guidance R.11. The Biowin 2 probability being 0.9908 > 0.5, and the Biowin 3 ultimate biodegradation time frame being "days-weeks" < months (value 3.4814 > 2.2), the criteria indicating that the substance does not biodegrade fast are not fulfilled. The Biowin 6 probability being 0.8691 > 0.5 and the Biowin 3 ultimate biodegradation time frame being "days-weeks" < months, the criteria indicating that the substance does not biodegrade fast are not fulfilled. So, the biodegradation prediction by BIOWIN does not lead to the conclusion that Decane would be persistent.

A persistence (P) screening assessment has been realized for undecane using EPI suite BIOWIN 2, 3 and 6 (v4.10) models, in accordance with Reach Guidance R.11. The Biowin 2 probability being 0.9888 > 0.5, and the Biowin 3 ultimate biodegradation time frame being "days-weeks" < months (value 3.4504 > 2.2), the criteria indicating that the substance does not biodegrade fast are not fulfilled. The Biowin 6 probability being 0.8718 > 0.5 and the Biowin 3 ultimate biodegradation time frame being "days-weeks" < months, the criteria indicating that the substance does not biodegrade fast are not fulfilled. So, the biodegradation prediction by BIOWIN does not lead to the conclusion that Undecane would be persistent.

Hydrocarbons, C10-C12, isoalkanes, <2% aromatics biodegraded to an extent of 31% after 28 days and 41% after 41 days during a non-acclimated phase of the test. Hydrocarbons, C10-C12, isoalkanes, <2% aromatics biodegraded to an extent of 42% after 28 days and 48% after 41 days during an acclimated phase of the test.

Hydrocarbons, C10-C12, isoalkanes, cyclics, <2% aromatics biodegraded to an extent of 7.34% after 24 days and 8.74% after 31 days. Hydrocarbons, C10-C12, isoalkanes, cyclics, <2% aromatics is not inherently biodegradable.

Hydrocarbons, C10-C13, isoalkanes, cyclics, <2% aromatics, biodegraded 89.8% after 28 days under the conditions of the study and is readily biodegradable.

Hydrocarbons, C10-C14, isoalkanes, cyclics, <2% aromatics biodegraded to an extent of 16.07% after 24 days and 18.39% after 31 days. Hydrocarbons, C10-C14, isoalkanes, cyclics, <2% aromatics is not inherently biodegradable.

Hydrocarbons, C11-C12, n-alkanes, <2% aromatics biodegraded to an extent of approximately 77% after 28 days. The data support characterizing Hydrocarbons, C11-C12, n-alkanes, <2% aromatics as rapidly biodegradable (readily biodegradable).

Hydrocarbons, C11-C14, n-alkanes, isoalkanes, cyclics, <2% aromatics, a multi-component substance, biodegraded to an extent of 69% after 28 days. The data support characterizing Hydrocarbons, C11-C14, n-alkanes, isoalkanes, cyclics, <2% aromatics as rapidly biodegradable, readily biodegradable, not expected to persist in the environment under aerobic conditions. Although it did not meet the 10-day window requirement, it is characterized as readily biodegradable because the criterium is not applied to multi-component substances when assessing their ready biodegradability.

A persistence (P) screening assessment has been realized for dodecane using EPI suite BIOWIN 2, 3 and 6 (v4.10) models, in accordance with Reach Guidance R.11. The Biowin 2 probability being 0.9863 > 0.5, and the Biowin 3 ultimate biodegradation time frame being "days-weeks" < months (value 3.4194 > 2.2), the criteria indicating that the substance does not biodegrade fast are not fulfilled. The Biowin 6 probability being 0.8746 > 0.5 and the Biowin 3 ultimate biodegradation time frame being "days-weeks" < months, the criteria indicating that the substance does not biodegrade fast are not fulfilled. So, the biodegradation prediction by BIOWIN does not lead to the conclusion that Dodecane would be persistent.

Hydrocarbons, C12-C13, isoalkanes, cyclics, <2% aromatics biodegraded to an extent of 12.69% after 24 days and 13.69% after 31 days. Hydrocarbons, C12-C13, isoalkanes, cyclics, <2% aromatics is not inherently biodegradable.

Hydrocarbons, C12-C16, isoalkanes, cyclics, <2% aromatics biodegraded to an extent of 22% after 28 days and 50% after 70 days. Hydrocarbons, C12-C16, isoalkanes, cyclics, <2% aromatics is not readily biodegradable, but can be considered inherently biodegradable.

Hydrocarbons, C12-C16, n-alkanes, isoalkanes, cyclics, <2% aromatics, a multi-component substance, biodegraded to an extent of 68% after 28 days and 69% after 31 days. The data support characterizing Hydrocarbons, C12-C16, n-alkanes, isoalkanes, cyclics, <2% aromatics as rapidly biodegradable, readily biodegradable, not expected to persist in the environment under aerobic conditions. Although it did not meet the 10-day window requirement, it is characterized as readily biodegradable because the criterium is not applied to multi-component substances when assessing their ready biodegradability.

Tridecane biodegraded to an extent of 83% after 28 days and 86% after 32 days. The data support characterizing tridecane as rapidly biodegradable (readily biodegradable).

Hydrocarbons, C13-C14, n-alkanes, <2% aromatics biodegraded to an extent of approximately 79% after 28 days. The data support characterizing Hydrocarbons, C13-C14, n-alkanes, <2% aromatics as rapidly biodegradable (readily biodegradable).

Hydrocarbons, C13-C15, isoalkanes, cyclics, <2% aromatics biodegraded to an extent of 16.95% after 24 days and 20.62% after 31 days. Hydrocarbons, C13-C15, isoalkanes, cyclics, <2% aromatics is not inherently biodegradable.

Tetradecane biodegraded to an extent of approximately 80% after 28 days and 38 days. The data support characterizing tetradecane as rapidly biodegradable (readily biodegradable).

A persistence (P) screening assessment has been realized for tetradecane using EPI suite BIOWIN 2, 3 and 6 (v4.10) models, in accordance with Reach Guidance R.11. The Biowin 2 probability being 0.9797 > 0.5, and the Biowin 3 ultimate biodegradation time frame being "days-weeks" < months (value 3.3574 > 2.2), the criteria indicating that the substance does not biodegrade fast are not fulfilled. The Biowin 6 probability being 0.8799 > 0.5 and the Biowin 3 ultimate biodegradation time frame being "days-weeks" < months, the criteria indicating that the substance does not biodegrade fast are not fulfilled. So, the biodegradation prediction by BIOWIN does not lead to the conclusion that Tetradecane would be persistent.