Esterification product of castor oil and tetrahydromethyl-1,3-isobenzofuranedione

Biodegradation in water: screening tests

Administrative data

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:

other: guideline study and GLP

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2008

Report date:

2008

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

1

Reference substance name:

Esterification product of castor oil and tetrahydromethyl-1,3-isobenzofuranedione

EC Number:

700-064-6

Cas Number:

2105830-60-0

Molecular formula:

Not applicable as this is a UVCB substance

IUPAC Name:

Esterification product of castor oil and tetrahydromethyl-1,3-isobenzofuranedione

Study design

Oxygen conditions:

aerobic

Inoculum or test system:

activated sludge, domestic, non-adapted

Duration of test (contact time):

29 d

Initial test substance concentration

Initial conc.:

17 mg/L

Based on:

test mat.

Parameter followed for biodegradation estimation

Parameter followed for biodegradation estimation:

CO2 evolution

Reference substance

Reference substance:

acetic acid, sodium salt

Results and discussion

% Degradation

Parameter:

% degradation (CO2 evolution)

Value:

2 - 14

Sampling time:

29 d

Details on results:

Determination of ‘ready’ biodegradability: carbon dioxide (CO2) evolution test (modified Sturm test) with the Substance.
The study procedure was based on EEC directive 92/69, C.4-C, December 1992, OECD guideline No. 301 B July 17, 1992 and
ISO Standard 9439 (1999). The Substance was a very viscous amber liquid. The Substance was tested in duplicate at
approximately 34 mg per 2 litres, corresponding to 12 mg TOC/l. The organic carbon content was based on the composition
and structure. Preparation was as much as possible performed under yellow light and/or dimmed light conditions. The
Theoretical CO2 production (ThCO2) of the Substance was estimated to be 2.60 mg CO2/mg.
In a pre-test the Substance was not sufficiently soluble to allow preparation of an aqueous solution at a concentration
of 1 g/l. Therefore, the Substance was weighed on glass slides and quantitatively added to the test bottles (2 litres)
containing medium with microbial organisms and mineral components. The test solutions were continuously stirred during
the test, to ensure optimal contact between the test substance and the test organisms. The relative degradation values calculated
from the measurements performed during the test period revealed 14 and 2% degradation of the Substance, for the duplicate
bottles tested. Thus, the criterion for ready biodegradability (at least 60% biodegradation within a 10-day window) was not met.
In the toxicity control, the Substance was found not to inhibit microbial activity. Since all criteria for acceptability of the test
were met, this study was considered to be valid. In conclusion, the Substance is designated as not readily biodegradable.

Any other information on results incl. tables

Reference substance

Identification number RS186

Name Sodium acetate

Description White powder (determined at NOTOX)

Molecular formula CH3COONa (taken from label)

Molecular weight 82.03 (taken from label)

Batch number K34333668

Article number 1.06268.0250

Purity 99.0%

Expiry Date 28 February 2010

Certified Yes

Storage conditions At room temperature in the dark

Supplier Merck, Darmstadt, Germany

Reference substance concentration and preparation of test solutions

A solution of sodium acetate was prepared by dissolving 402.0 mg in Milli-RO water and making

this up to a total volume of 100 ml. Volumes of 20 ml from this stock solution were added to 2

litres of the test medium of the positive control bottle and the toxicity control bottle, resulting in a

final concentration of 40 mg sodium acetate per litre (12 mg TOC/l).

Applicant's summary and conclusion

Validity criteria fulfilled:

yes

Interpretation of results:

under test conditions no biodegradation observed

Conclusions:

The Substance was not readily biodegradable under the conditions of the modified Sturm
test presently performed.

Executive summary:

SUMMARY

Determination of ‘ready’ biodegradability: carbon dioxide (CO2) evolution test (modified Sturm

test) with the Substance.

The study procedure was based on EEC directive 92/69, C.4-C, December 1992, OECD

guideline No. 301 B July 17, 1992 and ISO Standard 9439 (1999).

The Substance was a very viscous amber liquid. The Substance was tested in duplicate

at approximately 34 mg per 2 litres, corresponding to 12 mg TOC/l. The organic carbon content

was based on the composition and structure. Preparation was as much as possible performed

under yellow light and/or dimmed light conditions. The Theoretical CO2 production (ThCO2) of

the Substance was estimated to be 2.60 mg CO2/mg.

In a pre-test the Substance was not sufficiently soluble to allow preparation of an aqueous

solution at a concentration of 1 g/l. Therefore, the Substance was weighed on glass slides

and quantitatively added to the test bottles (2 litres) containing medium with microbial organisms

and mineral components. The test solutions were continuously stirred during the test, to ensure

optimal contact between the test substance and the test organisms.

The relative degradation values calculated from the measurements performed during the test

period revealed 14 and 2% degradation of the Substance, for the duplicate bottles tested.

Thus, the criterion for ready biodegradability (at least 60% biodegradation within a 10-day

window) was not met.

In the toxicity control, the Substance was found not to inhibit microbial activity.

Since all criteria for acceptability of the test were met, this study was considered to be valid.

In conclusion, the Substance is designated as not readily biodegradable.