Reaction products of “Fatty Acids, C16-18 and C18-unsatd., Me esters; sulfuric acid and sodium hydroxide

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:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

OECD Guideline 301 B (Ready Biodegradability: CO2 Evolution Test)

GLP compliance:

yes

Specific details on test material used for the study:

Batch: 2018060002
pH: 7.60
moisture content: 30.29%

Oxygen conditions:

aerobic

Inoculum or test system:

sewage, predominantly domestic, non-adapted

Remarks:

from the aeration stage of the Severn Trent Water Plc sewage treatment plant at Loughborough, Leicestershire, UK,

Details on inoculum:

The activated sewage sludge sample was washed twice by settlement and re-suspension in mineral medium to remove any excessive amounts of Dissolved Organic Carbon (DOC) that may have been present. The washed sample was then maintained on continuous aeration in the laboratory at a temperature of approximately 21 ºC and used on the day of collection. Determination of the suspended solids level of the activated sewage sludge was carried out by filtering a sample (100 mL) of the washed activated sewage sludge by suction through a pre-weighed Whatman GF/A filter paper* using a Buchner funnel. Filtration was then continued for a further 3 minutes after rinsing the filter three successive times with 10 mL of deionized reverse osmosis water. The filter paper was then dried in an oven at approximately 105 ºC for at least 1-Hour and allowed to cool before weighing. This process was repeated until a constant weight was attained. The suspended solids concentration was equal to 3.4 g/L prior to use.

Duration of test (contact time):

28 d

Initial conc.:

10 mg/L

Based on:

other: carbon

Parameter followed for biodegradation estimation:

CO2 evolution

Reference substance:

benzoic acid, sodium salt

Parameter:

% degradation (CO2 evolution)

Value:

50

Sampling time:

28 d

Validity criteria fulfilled:

yes

Interpretation of results:

not readily biodegradable

Conclusions:

The test item attained 50% biodegradation after 28 days and therefore cannot be considered to be readily biodegradable under the strict terms and conditions of OECD Guideline No. 301B.

Executive summary:

The test item attained 50% biodegradation after 28 days and therefore cannot be considered to be readily biodegradable under the strict terms and conditions of OECD Guideline No. 301B.

Description of key information

The test item RICOIL EN attained 50% biodegradation after 28 days and therefore cannot be considered to be readily biodegradable under the strict terms and conditions of OECD Guideline No. 301B.

Key value for chemical safety assessment

Biodegradation in water:

not biodegradable

Type of water:

freshwater