Hydrocarbons, C18-C24, iso-alkanes <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:

The study was conducted between 16 June 2014 and 17 July 2014.

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

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

Deviations:

no

Qualifier:

according to guideline

Guideline:

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

Deviations:

no

Qualifier:

according to guideline

Guideline:

EPA OPPTS 835.3110 (Ready Biodegradability)

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Oxygen conditions:

aerobic

Inoculum or test system:

activated sludge, domestic (adaptation not specified)

Details on inoculum:

Test System
A mixed population of sewage treatment micro-organisms was obtained on 16 June 2014 from the final effluent stage of the Severn Trent Water Plc sewage treatment plant at Loughborough, Leicestershire, UK, which treats predominantly domestic sewage.


Preparation of Inoculum
The sample of effluent was filtered through coarse filter paper (first approximate 200 mL discarded) and maintained on aeration in a temperature controlled room at 21 ± 1 ºC prior to use.

Duration of test (contact time):

28 d

Initial conc.:

100 mg/L

Based on:

test mat.

Details on study design:

Experimental Preparation
Test Item
At the request of the Sponsor and following the recommendations of the International Standards Organisation (ISO, 1995) the test item was dispensed onto a GF/A filter paper (21 mm) supported on aluminium foil prior to addition to the test vessels. Using this method enables relatively small amounts of test item to be added accurately to the test vessels.

A nominal amount of test item (50 mg) was weighed onto filter paper supported on aluminium foil and added to mineral medium (495 mL) prior to the addition of inoculum (5 mL) to give the test concentration of 100 mg/L. Due to the volatile nature of the test item each vessel was placed immediately on the respirometer after the addition of the inoculum.

A test concentration of 100 mg/L was selected for use in the study following the recommendations of the Test Guideline.

A filter paper supported on aluminium foil was added to each inoculum control vessel in order to maintain consistency between the test and inoculum control vessels.


Reference Item
A reference item, aniline (C6H5NH2), was used to prepare the procedure control vessels. An initial stock solution of 1000 mg/L was prepared by dissolving the reference item directly in mineral medium. An aliquot (50 mL) of this stock solution was diluted with mineral medium (445 mL) and the inoculum (5 mL), to give the test concentration of 100 mg/L. The volumetric flask containing the stock solution was inverted several times to ensure homogeneity.

A filter paper supported on aluminium foil was added to each vessel in order to maintain consistency between the test and procedure control vessels.


Toxicity Control
A toxicity control, containing the test item and aniline, was prepared in order to assess any toxic effect of the test item on the sewage treatment micro-organisms used in the test.

A nominal amount of test item (50 mg) was weighed onto filter paper supported by aluminium foil and added to mineral medium (445 mL) and an aliquot (50 mL) of the 1000 mg/L aniline stock solution prior to the addition of inoculum (5 mL) to give the test concentration of 100 mg test item/L and 100 mg aniline/L. Due to the volatile nature of the test item each vessel was immediately placed on the respirometer after the addition of the inoculum.


Abiotic Test
A nominal amount of sodium azide (5.00 g) was dissolved in mineral medium and the volume adjusted to 250 mL to give a 20 g/L stock solution.

A nominal amount of test item (50 mg) was weighed onto filter paper supported by aluminium foil and added to mineral medium (495 mL) with an aliquot (5.0 mL) of the 20 g/L sodium azide stock solution to give the test concentration of 100 mg test item/L and 200 mg sodium azide/L. Due to the volatile nature of the test item each vessel was immediately placed on the respirometer after the addition of the inoculum.


Preparation of Test System
The following test preparations were prepared and inoculated in 500 mL bottles:
a) Five replicate bottles containing inoculated mineral medium to act as the inoculum control.
b) Two replicate bottles containing inoculated mineral medium and the reference item, aniline, at a concentration of 100 mg/L.
c) Five replicate bottles containing inoculated mineral medium and the test item at a concentration of 100 mg/L.
d) Two replicate bottles containing inoculated mineral medium the reference item, aniline, at a concentration of 100 mg/L and the test item at a concentration of 100 mg/L to act as toxicity control vessels.
e) Four replicates bottles containing the test item at a concentration of 100 mg/L and sodium azide at a concentration of 200 mg/L to act as abiotic test vessels.

Where appropriate all vessels were inoculated with the prepared inoculum at a rate of 1% v/v.

In order to confirm that the aniline stock solution was prepared correctly, a diluted, 100 mg/L stock solution (in reverse osmosis water) was also sampled for DOC analysis.

Two of the five inoculum control, abiotic test vessels and test item vessels were sacrificed for immediate chemical analysis. All remaining inoculum control, abiotic test vessels and test item, procedure control and toxicity control vessels were placed in a CES Multi-Channel Aerobic Respirometer.

The system consists of a sample flask sealed by a sensor head/CO2 trap immersed in a temperature controlled water bath. The samples were stirred for the duration of the test with a magnetically coupled stirrer.

As biodegradation progresses, the micro-organisms convert oxygen to carbon dioxide which is absorbed into the ethanolamine solution (50% v/v) causing a net reduction in gas pressure within the sample flask. The pressure reduction triggers the electrolytic process, generating oxygen and restoring the pressure in the sample flask. The magnitude of the electrolyzing current and the duration of the current is proportional to the amount of oxygen supplied to the micro-organisms. The data generated from the respirometer’s own battery backed memory was collected on the hard disk drive of a non-dedicated computer.

The test was conducted in diffuse light at a temperature of approximately 23 ºC.

An additional replicate vessel was prepared for each treatment and incubated in order that in the event of a leak in the test system a replicate vessel could be discarded without jeopardizing the integrity of the test. On Day 28 an assessment of the biological oxygen demand data was made and the most consistent vessels chosen for calculating and reporting purposes. The remaining vessels were discarded and are not reported.

Data Evaluation
Calculation of Theoretical Oxygen Demand
The Theoretical Oxygen Demand (ThOD) for a compound CcHhClclNnPpSsOoNana was calculated by:

ThOD (NO3)(mgO2 / mg) = (16(2c + ½(h-lc) + 4/2n + 5/2p + 3s + ½na – o) / molecular weight


Percentage Biodegradation
The percentage biodegradation in terms of oxygen consumption was calculated as follows:

% degradation = (BOD B / ThOD) x 100

Where:
BOD = Biological Oxygen Demand of the test item or reference item (mgO2/L)
B = Oxygen consumption in basal mineral medium to which inoculum is added (control) (mgO2/L)
ThOD = Theoretical oxygen demand to completely oxidize the reference and/or test item (mgO2/L)

Reference substance:

aniline

Parameter:

% degradation (O2 consumption)

Value:

74

Sampling time:

28 d

Details on results:

Biodegradation
The test item attained 74% biodegradation after 28 days and can therefore be considered to be readily biodegradable. The test item failed to meet the 10-Day window validation criterion, whereby 60% biodegradation must be attained within 10 days of the biodegradation exceeding 10%. However, in accordance with the Revised Introduction to the OECD Guidelines for Testing of Chemicals, Section 3, Paragraph 43 (Page 8), if testing on a complex mixture is performed, and it is anticipated that a sequential biodegradation of the individual structures takes place, then the 10-Day window should not be applied to interpret the results of the test.

The toxicity control attained 62% biodegradation after 14 days and 77% biodegradation after 28 days thereby confirming that the test item was not toxic to the sewage treatment micro-organisms used in the test.

Chemical analysis of the 100 mg/L test preparation at 0 hours showed a mean measured concentration of 50% of nominal was obtained. A decline in the mean measured test concentration was observed on Day 28 to 30% of nominal (70% loss over the test duration assuming 100% recovery on Day 0).

Based on previous experience obtained, it was considered that the use of preliminary absorption onto filter paper may have contributed to the low measured concentration observed on Day 0. Preliminary recovery analyses performed at a concentration of 100 mg/L indicated that 102% recovery occurred when the test item was directly dispensed into the test vessel. However, when the test item was adsorbed onto filter paper only 54% recovery occurred.

As such the low results obtained from the Day 0 analysis of the test vessels were a result of incomplete recovery of the test item after adsorption onto filter paper rather than incorrect preparation. It was therefore considered that the incubated test vessels contained the required concentration of test item.

The losses based on oxygen consumption were slightly higher than those observed by chemical analysis. This was considered to be due to an increase in the numbers of viable micro-organisms in the test item vessels as a result of the readily biodegradable nature of the test item. This effect occurs due to the micro-organisms utilizing the test item as a carbon source for cellular growth resulting in a greater number of viable micro-organisms in these vessels. The increased number of micro-organisms in these vessels gave rise to increased respiration rates and hence biodegradation based on oxygen consumption was higher than that based on chemical analysis.

Chemical analysis of the abiotic test vessels on Day 0 showed a mean measured concentration of 58% of nominal was obtained. It was considered, as for the test item vessels, that the low measured concentrations were attributable to incomplete recovery of the test item from the filter paper. Analysis on Day 28 showed a mean measured concentration of 86% of nominal was obtained. Assuming the test vessels contained the required concentration of 100 mg/L on Day 0, then a 14% loss of test item occurred, by means of chemical analysis on Day 28. It was considered that these losses may have occurred during sampling and analysis given the volatile nature of the test item

Results with reference substance:

Aniline (procedure control) attained 80% biodegradation after 14 days and 84% biodegradation after 28 days thereby confirming the suitability of the inoculum and test conditions.

Validation Criteria

The mean BOD of the inoculated mineral medium (control) was 44.61 mg O₂/L after 28 days and therefore satisfied the validation criterion given in the OECD Test Guidelines.

 

The difference between extremes of replicate BOD values at the end of the test and at the end of the 10-Day window was less than 20% and therefore satisfied the validation criterion given in the OECD Test Guidelines.

Validity criteria fulfilled:

yes

Interpretation of results:

readily biodegradable

Conclusions:

Hydrocarbons, C18-C24, isoalkanes, <2% aromatics has been tested in an OECD 301F (manometric respirometry) test conducted in compliance with GLP. The test substance attained 74% biodegradation in 28 days and was therefore considered to be readily biodegradable.

Executive summary:

Introduction

The study was performed to assess the ready biodegradability of the test item in an aerobic aqueous media. The method followed was designed to be compatible with the OECD Guidelines for Testing of Chemicals (1992) No. 301F, “Ready Biodegradability; Manometric Respirometry Test” referenced as method C.4-D of Commission Regulation (EC) No. 440/2008 and US EPA Fate, Transport, and Transformation Test Guidelines OCSPP 835.3110 (Paragraph (q)).

 

Methods…….

The test item at a concentration of 100 mg/L was exposed to sewage treatment micro-organisms with mineral medium in sealed culture vessels in diffuse light at temperatures of between 23 and 24 ºC for 28 days. 

The biodegradation of the test item was assessed by the measurement of daily oxygen consumption values and compound specific analyses on Days 0 to 28. Control solutions with inoculum and the reference item, aniline, together with a toxicity control were used for validation purposes.

 

Results…….

The test item attained 74% biodegradation after 28 days and can therefore be considered to be readily biodegradable. 

 

Chemical analysis of the 100 mg/L test preparation at 0 hours showed a mean measured concentration of 50% of nominal was obtained. A decline in the mean measured test concentration was observed on Day 28 to 30% of nominal (70% loss over the test duration assuming 100% recovery on Day 0). 

 

Based on previous experience obtained, it was consideredthat the use of preliminary absorption onto filter paper may have contributed to the low measured concentration observed on Day 0. Preliminary recovery analyses performed at a concentration of 100 mg/L indicated that 102% recovery occurred when the test item was directly dispensed into the test vessel. However, when the test item was adsorbed onto filter paper only 54% recovery occurred. 

 

As such the low results obtained from the Day 0 analysis of the test vessels were a result of incomplete recovery of the test item after adsorption onto filter paper rather than incorrect preparation. It was therefore considered that the incubated test vessels contained the required concentration of test item.

 

The losses based on oxygen consumption were slightly higher than those observed by chemical analysis. This was considered to bedue to an increase in the numbers of viable micro-organisms in the test item vessels as a result of the readily biodegradable nature of the test item. This effect occurs due to the micro-organisms utilizing the test item as a carbon source for cellular growth resulting in a greater number of viable micro-organisms in these vessels. The increased number of micro-organisms in these vessels gave rise to increased respiration rates and hence biodegradation based on oxygen consumption was higher than that based on chemical analysis.

 

Chemical analysis of the abiotic test vessels on Day 0 showed a mean measured concentration of 58% of nominal was obtained. It was considered, as for the test item vessels, that the low measured concentrations were attributable to incomplete recovery of the test item from the filter paper. Analysis on Day 28 showed a mean measured concentration of 86% of nominal was obtained. Assuming the test vessels contained the required concentration of 100 mg/L on Day 0, then a 14% loss of test item occurred, by means of chemical analysis on Day 28. It was considered that these losses may have occurred during sampling and analysis given the volatile nature of the test item.

Reference 2

Endpoint:

biodegradation in water: ready biodegradability

Type of information:

experimental study

Adequacy of study:

supporting study

Study period:

The study was conducted from 23 September to 21 October 2015

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

OECD Guideline 306 (Biodegradability in Seawater)

GLP compliance:

yes (incl. QA statement)

Specific details on test material used for the study:

See test material information

Oxygen conditions:

aerobic

Inoculum or test system:

natural water: marine

Details on inoculum:

- Source of inoculum/activated sludge (e.g. location, sampling depth, contamination history, procedure):
Dilution water
Natural seawater was collected from the CEFAS laboratories at Lowestoft and may be regarded as "clean". The seawater was transferred into the CEFAS laboratories through a pipe which extends below the sand some distance into the bay. The sand acts as the first stage of filtration.
Date of collection: 21 August 2015
Temperature at the collection 15ºC
Storage conditions prior to test: required temperature 15±2°C; actual temperature 13.7-17.0ºC
Salinity at start of test: 30 parts per thousand
Temperature at start of test: 19.4°C

- Pre-treatment: Settled during the ageing stage and decanted prior to the start of the test. The seawater was filtered in the Chemex laboratory using Whatman 54 filters. It was then transferred to CT3 laboratory prior to the start of the test to equilibrate to the test temperature.

- Preparation of inoculum for exposure: Mineral media was prepared by the addition of mineral nutrient stock solutions to the aged seawater, aerating it strongly for 50 minutes and letting it stand for 23 hours and 32 minutes.

- Water filtered: yes

- Type and size of filter used, if any: Whatman 54 filters

Duration of test (contact time):

28 d

Initial conc.:

2.08 mg/L

Based on:

test mat.

Parameter followed for biodegradation estimation:

other: The degradation is defined as the ratio of the biochemical oxygen demand (BOD) within 28 days to either the theoretical oxygen demand (ThOD) or the chemical oxygen demand (COD).

Details on study design:

Principle of the test method
The test vessels are closed filled bottles containing the test substance dissolved in the dilution water. The bottles are incubated in the dark in the range 15 – 20°C (controlled to ±1°C) and the degradation is followed by analysis of the dissolved oxygen over a 28 day period.

The 28 day marine BOD was determined by a procedure following the OECD Guidelines for Testing of Chemicals reference 306.

The test material was stated to be insoluble in water, therefore a surfactant was used to emulsify the sample. To prepare the emulsion, 0.5208g of Shell GTL Solvent GS 310 (Hydrocarbons C18-C24, isoalkanes, <2% aromatics) was intimately mixed with a 0.2507g of non-ionic surfactant (IGEPAL CA 630). The emulsion was gradually diluted by the addition of deionised water and then made up to volume (500ml). A stable emulsion was produced.
Replicate standard BOD bottles were filled with the test concentration, prepared by addition of a sample stock solution to mineral media (2.0ml/l). A series of test bottles was prepared with mineral media only for the determination of "blank" losses. To check the integrity of the test procedure, a readily degradable reference chemical, sodium acetate, was tested at 5.01mg/l. A series of bottles containing mineral media plus IGEPAL CA 630, at the same final concentration as used in the test sample bottles (1mg/l), was run as a control and this was used as the blank value for the test material.

Initial dissolved oxygen (DO) concentrations were measured using a dissolved oxygen meter. The dissolved oxygen meter was set to the salinity of the mineral media and calibrated. The DO probe was inserted into the BOD bottles and the DO value was recorded when the reading was stable.

The bottles were then incubated in the dark at the temperature range between 18.7-19.1°C for the duration of the test period. Further measurements of dissolved oxygen concentration were made on bottles removed after 7, 14, 21, 24 and 28 days.

Control data (blank, reference and control) is classed as common data and may be used for other studies run at the same time. The data was recorded on the separate ‘common data’ lab-book.

Reference substance:

acetic acid, sodium salt

Parameter:

other: % degradation

Remarks:

ratio of the biochemical oxygen demand (BOD) within 28 days to either the theoretical oxygen demand (ThOD) or the chemical oxygen demand (COD).

Value:

52

Sampling time:

28 d

Details on results:

Shell GTL Solvent GS 310 (Hydrocarbons C18-C24, isoalkanes, <2% aromatics) failed to meet the requirements for a pass in this test (³60% degradation relative to the ThOD value - a maximum of 53% was recorded). However, because of the stringency of the test, this does not necessarily mean that the test substance is not biodegradable in the marine environment, but indicates that more work would be necessary to establish biodegradability.
Shell GTL Solvent GS 310 (Hydrocarbons C18-C24, isoalkanes, <2% aromatics) was stated to be insoluble in water, a surfactant (IGEPAL CA 630) was used to emulsify the sample. The effects of surfactant degradation were taken into account when calculating the degradation of the test material.
The guideline requires that the reference material degrades by at least 60% of its ThOD, and that the blank dissolved oxygen loss should not exceed 30% of the initial oxygen concentration.
Both of these criteria were satisfied for this test; a maximum value of 67% degradation of the sodium acetate was achieved on day 21 and the maximum blank DO loss was 11.9% on day 28.
The ThOD value used in this study was provided by the Sponsor.

Results with reference substance:

Sodium acetate was tested at 5.01mg/l: % Biodegradation was 60% in 28 days.

Table 1: Biochemical Oxygen demand. The DO measurements and calculated BOD values for the test substance and reference material

	Incubation period (days)
	0	7		14		21			24			28
Incubation Temperature (°C)	18.9	18.9		19		19			18.9			18.9
Average blank - DO (mg/l)	7.70	7.11		7.09		7.08			-			6.78
Average control - DO (mg/l)	7.74	7.18		6.73		6.68			6.46			6.42
Replicate number	1	1	2	1	2	1	2	3	1	2	3	1	2	3
Test substance - DO (mg/l)	7.72	4.71	4.93	3.54	3.36	2.82	2.95	2.91	2.77	2.78	2.77	2.63	2.79	2.60
Test Substance - BOD (mg O2/g)	-	1178	1072	1524	1611	1846	1784	1803	1764	1760	1764	1813	1736	1827
Reference material – DO (mg/l)	7.73	5.11	5.03	4.64	4.53	4.49	4.53	4.50	-	-	-	4.75	4.36	4.33
Reference material BOD (mg O2/g)	-	405	421	495	517	523	515	521	-	-	-	411	489	495

Table 2: Degradation. The calculated percent degradation values for the test substance and reference material

	Incubation period (days)
	7		14		21			24			28
Replicate number	1	2	1	2	1	2	3	1	2	3	1	2	3
Test substance (%)	34	31	45	47	54	52	53	52	51	52	53	51	53
Average degradation (%)	33		46		53			52			52
Reference material (%)	52	54	63	66	67	66	67	-	-	-	53	63	63
Average degradation (%)	53		65		67			-			60

ThOD of sodium acetate 780mg O2/g.

Validity criteria fulfilled:

yes

Interpretation of results:

not readily biodegradable

Conclusions:

Hydrocarbons, C18-C24, isoalkanes, <2% aromatics has been tested in an OECD 306 (biodegradability in seawater) test conducted in compliance with GLP. The test substance attained 52% biodegradation in 28 days and was therefore considered to be not readily biodegradable.

Executive summary:

Introduction

The study was performed to assess the ready biodegradability of the test item in seawater. The method followed was designed to be compatible with the OECD Guidelines for Testing of Chemicals (1992) No. 306, Biodegradability in Seawater (closed bottle test).

 

Methods…….

The test material was stated to be insoluble in water, therefore a surfactant was used to emulsify the sample. To prepare the emulsion, 0.5208g of Shell GTL Solvent GS 310 (Hydrocarbons

C18-C24, isoalkanes, <2% aromatics) was intimately mixed with a 0.2507g of non-ionic surfactant (IGEPAL CA 630). The emulsion was gradually diluted by the addition of deionised

water and then made up to volume (500ml). A stable emulsion was produced.

Replicate standard BOD bottles were filled with the test concentration of 2.08 mg/l, prepared by addition of a sample stock solution to mineral mediaand incubated in the dark in the range 15 – 20°C (controlled to ±1°C).

The degradation is followed by analysis of the dissolved oxygen over a 28 day period.

Control solutions with mineral media only and the reference item, sodium acetate, were used for validation purposes.

 

Results…….

The test item attained 52% biodegradation after 28 days and can therefore be considered to be not readily biodegradable. 

However, because of the stringency of the test, this does not necessarily mean that the test substance is not biodegradable in the marine environment, but indicates that more work would be necessary to establish biodegradability.

 

Description of key information

The registration substance attained 74% biodegradation in 28 days in an OECD 301F (manometric respirometry) test conducted in compliance with GLP (Vryenhoef, 2014). It is therefore considered to be readily biodegradable.

Key value for chemical safety assessment

Biodegradation in water:

readily biodegradable

Additional information

The biodegradability of Hydrocarbons, C18-C24, isoalkanes, <2% aromatics has been tested in a study with the registered substance itself. The substance attained 74% biodegradation in 28 days in an OECD 301F (manometric respirometry) test conducted in compliance with GLP (Vryenhoef, 2014a). It is therefore considered to be readily biodegradable.

A second study with the registration substance Hydrocarbons, C18-C24, isoalkanes, <2% aromatics has tested the biodegradability of the substance in seawater in an OECD 306 (biodegradability in seawater) test, conducted in compliance with GLP (Drake, 2015).

The test substance attained 52% biodegradation in 28 days and was therefore considered to be not readily biodegradable under the conditions of the OECD 306 test.

In general terms, degradation can be seen to relate to the carbon range present in test material. This is consistent with water solubility limiting the rate of uptake by microorganisms.  

  

 In studies of any multi-constituent test substance, there will be uptake of the more bioavailable constituents first. If homologous series are present, it is possible that microorganisms will adapt to the general structural types present, but it is inevitable that rates will overall appear to be slower than for single substances.  

  

 Therefore, where studies show high rates of degradation, this can be considered to be indicative of the potential for high degradation in the environment, and such studies should be given higher weight in any overall assessment.  

Although degradation was achieved at different levels in the two available biodegradation in water screening tests OECD 301F and OECD 306), the freshwater biodegradability study conducted (OECD 301F) on GS310 indicates that this substance is considered to be readily biodegradable (ignoring the inapplicable 10-day window criterion) (Commission Regulation (EU) No 286/2011 pg 24; ECHA 2017 pg 210). Degradation behaviour of structurally-similar substances in other screening studies in seawater are consistent with the conclusion that GS310 is readily biodegradable.

Data for the read-across substances GTL Gasoil (C8-26) and GTL Baseoil Distillates (C18-C50) are included to support the read-across of biodegradation in soil data for these two source substances to the target substance Hydrocarbons C18-C24, isoalkanes, <2% aromatics.

GTL Gasoil

The biodegradation in water screening tests with GTL Gasoil (C8-C26) showed varying levels of degradation, however, three biodegradability studies conducted on samples of GTL Gasoil indicate that this substance is considered to be readily biodegradable (ignoring the inapplicable 10-day window criterion) (Commission Regulation (EU) No 286/2011 pg 24; ECHA  2017 pg 210). The overall conclusion is that GTL Gasoil is readily biodegradable.  

GTL Baseoil

The results of ready biodegradation studies with GTL Base Oil 3 (C18-C50) vary, typically attaining between 40 and 70% degradation in 28 days. Based on weight of evidence the GTL Base Oil 3 is considered to be readily biodegradable, a view endorsed by the UK Centre for Environment, Fisheries and Aquaculture Science (Cefas) when they reviewed the data supplied for GTL Base Oil 3 under the OSPAR HOCNF (Oslo and Paris Commission Harmonised Offshore Chemical Notification Format) for their Offshore Chemical Notification Scheme (OCNS).

The data for GS310 has not been reviewed by OSPAR HOCNF, but a similar conclusion would be expected for GS310.

Conclusion for GS310

It is concluded that GS310 is readily biodegradable, based on the result of the OECD 301F (manometric respirometry) test, taking into account the arguments above.