2-Octen-1-ylsuccinic anhydride, mixture of cis and trans

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:

supporting study

Study period:

July 8, 1994 to August 5, 1994

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

equivalent or similar to guideline

Guideline:

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

GLP compliance:

yes

Oxygen conditions:

aerobic

Inoculum or test system:

other: activated sludge and soil

Details on inoculum:

Inoculum: Equal Portions of
1) Supernatant of activated sludge collected from aeration channels of Rockaway Valley Regional Sewage Authority on 7/8/94 at 7:15 am
2) Soil extract from laboratory soil samples

Duration of test (contact time):

28 d

Initial conc.:

25 mg/L

Based on:

test mat.

Parameter followed for biodegradation estimation:

CO2 evolution

Details on study design:

Test Substance: n-octenyl succinic anhydride: approximately 25 ppm as C
The sample was prepared as follows: 8.4 ml of sample was added to 1 liter of distilled water. As this dilution was not instantly soluble, the mixture was placed on a gyratory shaker at 150 rpm for one hour and then placed in a separatory funnel. The top aqueous phase was found to have a TOC of 1,115 ppm. 22.4 ml of this stock solution was added to each liter of basal media to give a final TOC of approximately 25 ppm.

Reference substance:

aniline

Remarks:

Reference Substance: Aniline, prepared as 1000 ppm stock as C.

Parameter:

% degradation (CO2 evolution)

Value:

79.9

Sampling time:

28 d

Parameter:

% degradation (DOC removal)

Remarks:

Soluble or Dissolved Organic Carbon

Value:

73.2

Sampling time:

28 d

Parameter:

% degradation (CO2 evolution)

Value:

53.8

Sampling time:

10 d

Remarks on result:

other: does not meet pass criteria of 70% degradation within 10 days

Parameter:

% degradation (DOC removal)

Value:

40.6

Sampling time:

10 d

Remarks on result:

other: does not meet pass criteria of 70% degradation within 10 days

When tested as described herein, the following degradation rates were obtained after 28 days:                 

 

Sample	From CO2 Evolution	From SOC Reduction
n-octenyl succinic anhydride	79.9%	73.2%
Aniline (reference)	>100%	81.6%

The data were acceptable for basing a degradability determination on the SOC parameter. The data collected from this study meets “pass” criteria as defined by OECD and EPA guidelines because it did degrade more than 70% by SOC reduction during the test. However, these guidelines also “recommend” that biodegradation occur within ten days of the rate reaching ten percent. The data do not meet this criteria. It is the opinion of some that this requirement is an arbitrary restriction on microbial kinetics. 

In combination, the SOC and CO2 parameters serve as a duplicate check on biodegradability, especially when physical/chemical properties such as solubility, volatility, and adsorption of any constituent of the sample may pose a problem in testing accuracy. The CO2 rates for both n-octenyl succinic anhydride and the anline control are higher that the DOC achieved diodegration rates. This is unusual, but could be explained by the high background carbon in the blank controls. Endogenous respirations of the inocula in this test would have been higher in the test flasks than the blank flasks due to the addition of additional nutrients (in the form of the test/control samples). In other words, the separate calculated rates for the sample and the control appear to internally agree and support the observed values.

Validity criteria fulfilled:

yes

Remarks:

reference substance aniline and blank control had good results

Interpretation of results:

readily biodegradable, but failing 10-day window

Conclusions:

The data were acceptable for basing a degradability determination on the SOC parameter. The data collected from this study meets “pass” criteria for degradability as defined by OECD and EPA guidelines because it did degrade more than 70% by SOC reduction during the test. However, these guidelines also “recommend” that biodegradation occur within ten days of the rate reaching ten percent. The data do not meet this criteria. Therefore, this study concludes that n-octenyl succinic anhydride is readily biodegradable but not within the required 10 days.

Reference 2

Endpoint:

biodegradation in water: ready biodegradability

Type of information:

experimental study

Adequacy of study:

key study

Study period:

30 April 2002 to 27 May 2002

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

OECD Guideline 301 D (Ready Biodegradability: Closed Bottle Test)

Deviations:

no

GLP compliance:

yes

Oxygen conditions:

aerobic

Inoculum or test system:

other: aerated sewage sludge

Details on inoculum:

Aerated sewage sludge was obtained from Brazos River Authority Waste Water Division. It was aerated until use and then filtered through glass wool, the first portion was discarded.

Duration of test (contact time):

28 d

Initial conc.:

>= 2 - <= 10 mg/L

Based on:

test mat.

Parameter followed for biodegradation estimation:

O2 consumption

Remarks:

The degradation was measured by oxygen analyses. The oxygen in each duplicate set of solutions was measured using an Orion Model 820 Dissolved Oxygen Meter and recorded at each interval.

Reference substance:

other: Potassium Hydrogen Phthalate

Parameter:

% degradation (O2 consumption)

Value:

71.66

Sampling time:

19 d

Remarks on result:

other: average % biodegradation based on 2 replicates

Parameter:

% degradation (O2 consumption)

Value:

66.03

Sampling time:

16 d

Remarks on result:

other: average % biodegradation based on 2 replicates

Parameter:

% degradation (O2 consumption)

Value:

59.87

Sampling time:

14 d

Remarks on result:

other: average % biodegradation based on 2 replicates

Parameter:

% degradation (O2 consumption)

Value:

55.78

Sampling time:

12 d

Remarks on result:

other: average % biodegradation based on 2 replicates

Parameter:

% degradation (O2 consumption)

Value:

53.97

Sampling time:

9 d

Remarks on result:

other: average % biodegradation based on 2 replicates

Results with reference substance:

For a ready biodegradability test to be considered valid, a value of ≥ 60% must be obtained for the reference material within 15 days. A value of 64.72%
biodegradation was obtained on Day 9 for the reference material, potassium hydrogen phthalate.

Validity criteria fulfilled:

yes

Remarks:

A value of 64.72% biodegradation was obtained on Day 9 for the reference material, potassium hydrogen phthalate (valid if ≥ 60% within 15 days).

Interpretation of results:

readily biodegradable

Conclusions:

For test substance, OSA, a maximum of 71.66% biodegradation was obtained on Day 19 of the study. Therefore, in this study, OSA met the standard for ready biodegradability (value of ≥ 60% biodegradable within 28 days).

Executive summary:

In the study entitled “Ready Biodegradability: Closed Bottle Test by OECD 301D and OPPTS 835.311(o)” (Mullins – STILLMEADOW, 2002) the test substance, OSA, had a maximum biodegradation of 71.66% on day 19 of the 28 day study. Therefore, in this study, OSA met the standard for ready biodegradability (i.e., value of ≥ 60% biodegradable within 28 days).

Description of key information

The substance was shown to be readily biodegradable in a closed bottle test conducted in accordance with OECD Guideline 301D.  Biodegradation of 71.66% was reported on day 19 of the 28 day study. 

Key value for chemical safety assessment

Biodegradation in water:

readily biodegradable

Additional information

In the study entitled “Ready Biodegradability: Closed Bottle Test by OECD 301D and OPPTS 835.311(o)” (Mullins – STILLMEADOW, 2002). a maximum biodegradation of 71.66% on day 19 of the 28 day study was reported for the substance, thereby meeting the criterion for ready biodegradability (i.e., ≥ 60% biodegradation within 28 days). In a supporting study, the substance was shown to exhibit maximum biodegradation of 79.9%,, but failed the 10-day window, in a CO₂ evolution test conducted in accordance with OECD 301B.