1,10-Decanediamine, 4-methylbenzenesulfonate (1:2)

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)

Qualifier:

according to guideline

Guideline:

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

Deviations:

no

Qualifier:

according to guideline

Guideline:

EU Method C.4-C (Determination of the "Ready" Biodegradability - Carbon Dioxide Evolution Test)

Deviations:

no

Qualifier:

according to guideline

Guideline:

EPA OPPTS 835.3110 (Ready Biodegradability)

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Inoculum or test system:

activated sludge, domestic (adaptation not specified)

Details on inoculum:

- Type of inoculum: Mixed population of aquatic micro-organsisms
- Source: from the aeration stage of the Severn Trent Water Plc sewage treatment plant at Loughborough, Leicestershire, UK.
- Date of obtainment: 13 May 2019
- Preparation of inoculum for exposure: 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 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.
- Concentration of inoculum (dry weight): equal to 2.3 g/L prior to use.

Duration of test (contact time):

28 d

Reference substance:

benzoic acid, sodium salt

Key result

Parameter:

% degradation (CO2 evolution)

Value:

94

Sampling time:

28 d

Validity criteria fulfilled:

yes

Interpretation of results:

readily biodegradable

Conclusions:

1,10-Decanediamine, 4-methylbenzenesulfonate (1:2) attained 94% biodegradation after 28 days and satisfied the 10-day window validation criterion, whereby 60% biodegradation must be attained within 10 days of the biodegradation exceeding 10%. 1,10-Decanediamine, 4-methylbenzenesulfonate (1:2) item can therefore be considered to be readily biodegradable under the strict terms and conditions of OECD Guideline No. 301B.

Executive summary:

Indroduction: A study was performed to assess the ready biodegradability of the test item in an aerobic aqueous medium. The method followed was designed to be compatible with the OECD Guidelines for Testing of Chemicals (1992) No. 301B, "Ready Biodegradability; CO2 Evolution Test" referenced as Method C.4-C of Commission Regulation (EC) No. 440/2008 and US EPA Fate, Transport and Transformation Test Guidelines OCSPP 835.3110 (Paragraph (m)).

Method: The test item, at a concentration of 10 mg carbon/L, was exposed to activated sewage sludge micro-organisms with mineral medium in sealed culture vessels in the dark at temperatures of between 21 and 24 °C for 28 days.

The biodegradation of the test item was assessed by the determination of carbon dioxide produced. Control solutions with inoculum and the reference item, sodium benzoate, together with a toxicity control were used for validation purposes.

Result: The test item attained 94% biodegradation after 28 days and satisfied the 10-day window validation criterion, whereby 60% biodegradation must be attained within 10 days of the biodegradation exceeding 10%. The test item can therefore be considered to be readily biodegradable under the strict terms and conditions of OECD Guideline No. 301B.

Sodium benzoate attained 87% biodegradation after 14 days with greater than 60% degradation being attained in a 10-day window. These results confirmed the suitability of the inoculum and test conditions and satisfied the validation criterion given in the OECD Test Guidelines.

Description of key information

1,10-Decanediamine, 4-methylbenzenesulfonate (1:2) attained 94% biodegradation after 28 days and satisfied the 10-day window validation criterion, whereby 60% biodegradation must be attained within 10 days of the biodegradation exceeding 10%. 1,10-Decanediamine, 4-methylbenzenesulfonate (1:2) item can therefore 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:

readily biodegradable

Type of water:

other: aerobic aqueous medium