Reaction mass of L-isoleucine and octadecan-1-ol and ethanesulphonic acid and docosan-1-ol

Biodegradation in water: screening tests

Administrative data

Endpoint:

biodegradation in water: ready biodegradability

Type of information:

experimental study

Adequacy of study:

key study

Study period:

November-December 2009

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2009

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

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

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Test material

Test material information

Constituent 1

Reference substance name:

Reaction mass of L-isoleucine and octadecan-1-ol and ethanesulphonic acid and docosan-1-ol

EC Number:

931-105-8

Cas Number:

1156505-34-8

Molecular formula:

C26-30H56-64O5NS

IUPAC Name:

Reaction mass of L-isoleucine and octadecan-1-ol and ethanesulphonic acid and docosan-1-ol

Specific details on test material used for the study:

Synonym: Brassicyl Isoleucine Esylate (and) Brassica Alcohol
Lot No.: D 565-098
CAS No.: Not listed
Purity: 100%
Recertification Date: May 2011

Study design

Oxygen conditions:

aerobic

Inoculum or test system:

activated sludge, domestic, non-adapted

Details on inoculum:

The activated sludge used for this study was obtained from the Wareham Wastewater Treatment Plant, Wareham, Massachusetts, which receives primarily domestic waste. Approximately 8 liters of activated sludge was collected on 2 September 2009, and transported to Springborn Smithers. Upon arrival at Springborn Smithers, the sludge was passed through a 2-mm sieve, recombined, and centrifuged at 1000 rpm for 10 minutes. The supe natant was discarded, the sludge was washed with 500 mL mineral medium and the contents were centrifuged at least once again and the supernatant was discarded. The moisture content of the activated sludge was determined, using an automated moisture analyzer (Sartorius MA-150), to be 93.73% and the percent solids determined to be 6.27%. A 15 mg solids/mL inoculum solution was prepared (3.0 g dry weight sludge brought to 200 mL with mineral media) and aerated until used. The test substance flasks, the blank flasks, the procedural control flask and the toxicity control flask all received 6.0 mL of the inoculum to produce an inoculum concentration of 30 mg/L. In addition, a 50-g aliquot of fresh soil and a 50-g aliquot of Weweantic River sediment were collected near Springborn Smithers Laboratories. The soil and sediment were suspended in 1.0 L of Weweantic River water. The suspension was filtered through glass wool prior to use. A 3.0-mL aliquot of the soil/sediment filtrate was added to each test vessel containing 2991 mL of mineral medium and 6.0 mL of activated sludge

Duration of test (contact time):

28 d

Initial test substance concentration

Initial conc.:

10 mg/L

Based on:

TOC

Parameter followed for biodegradation estimation

Parameter followed for biodegradation estimation:

CO2 evolution

Reference substance

Reference substance:

benzoic acid, sodium salt

Results and discussion

% Degradation

Parameter:

% degradation (CO2 evolution)

Value:

78.08

Sampling time:

28 d

Details on results:

The mean cumulative net percent CO2 evolved (percent biodegradation) from the aqueous test medium fortified with Emulsense at 10 mg C/L was 78.08% on day 28. The toxicity control on day 14 was 50.93%, which indicates that Emulsense was not toxic to the inoculum in the test medium.

BOD5 / COD results

Results with reference substance:

The cumulative net percent CO2 evolved from the sodium benzoate procedural control was 63.30% of theoretical by day 7, thus exceeding the “pass” criteria of the test (reaching 60% or greater CO2 evolution within a 10-day window of reaching 10% biodegradation). This rapid biodegradation of sodium benzoate confirmed the presence of an active microbial population and system integrity.

Applicant's summary and conclusion

Validity criteria fulfilled:

yes

Interpretation of results:

readily biodegradable

Conclusions:

Although the 301B test guideline is intended for testing pure chemicals, it is sometimes relevant to examine the ready biodegradability of mixtures of structurally similar chemicals like oils and surface-active substances (surfactants). Since Emulsense is such a mixture, it is likely that sequential biodegradation of the individual structures is taking place. Therefore, the 10-day window should not be applied to interpret the results of this test. Based on the CO2 analysis during this study, Emulsense is classified as “readily biodegradable” according to the OECD 301B guideline.