2-[(1-amino-9,10-dihydro-4-hydroxy-9,10-dioxo-2-anthryl)oxy]ethyl phenyl carbonate

Biodegradation in water: screening tests

Link to relevant study record(s)

Reference

Endpoint:

biodegradation in water: screening test, other

Remarks:

Inherent biodegradation test

Type of information:

experimental study

Adequacy of study:

key study

Study period:

26 January 2000 to 23 February 2000.

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

OECD Guideline 302 C (Inherent Biodegradability: Modified MITI Test (II))

Deviations:

yes

Remarks:

The test substance was run in duplicate instead of in triplicate.

GLP compliance:

no

Oxygen conditions:

aerobic

Inoculum or test system:

other: Mixture of polyvalent bacteria (Activated sludge obtained from a communal waste-water treatment plant).

Details on inoculum:

Test organism:
Strain / Inoculation: Mixture of polyvalent bacteria (activated sludge) collected on January 25, 2000, from the aeration tank of a domestic sewage treatment plant, PRO RHENO Basel communal. The pH value of the activated sludge was 6.6.

Sludge pre-treatment: The activated sludge was washed 4 times with tap water and one time with test medium. Subsequently the sludge was aerated until use. A sample of the activated sludge was taken to determine the dry weight of the suspended solids.

Bacteria concentration: 100 mg/l suspended solids. The bacteria concentration was obtained by adding 10.4 ml of the pre-treated sludge (9.6 g/l SS) per 1000 ml test medium.

Duration of test (contact time):

28 d

Initial conc.:

30 mg/L

Parameter followed for biodegradation estimation:

O2 consumption

Details on study design:

Experimental conditions:
-Temperature: 25 °C
-Test duration: 28 days
-Lighting: darkness

Stock solution and test concentrations:
-Stock solution 2.5 g/500 ml reference substance in distilled water
-Test concentrations 100 mg/l of the reference substance (20 ml stock solution in 1000 ml test medium).

-30 mg/l of the test substance
-Because the test substance was not completely soluble in the test medium it was given directly into the test system without preparation of a stock
solution.

Directly weighing:
-7.4 mg test substance/ 250 ml test medium in flask 7
-7.4 mg test substance/ 250 ml test medium in flask 8
-7.6 mg test substance/ 250 ml test medium in flask 9

Test medium:
The mineral salts for each of the following stock solutions were dissolved in 1 litre of distilled water.

Stock solution A:
-8.5 g of potassium acid phosphate, 21.75 g of di-potassium hydrogen phosphate, 22.18 g of di-sodium hydrogenphosphate dihydrate and 1.7 g of ammonium chloride. The pH value of this solution was 7.2.

Stock solution B:
36.4 g of calcium chloride dihydrate

Stock solution C
22.5 g of magnesium sulfate heptahydrate

Stock solution D
0.25 g of ferric chloride hexahydrate

3 ml of each of the following stock solutions were added per 1 litre distilled water to form the test medium.

Reference substance:

other: Sodium benzoate

Key result

Parameter:

% degradation (O2 consumption)

Value:

21

Sampling time:

28 d

Key result

Parameter:

BOD5

Value:

0 mg O2/g test mat.

Results with reference substance:

Biodegradation of the reference substance after 7 days 74 %.
-after 14 days 88 %
-after 28 days 100 %

-Degradation in the abiotic control after 28 days 0 %

Validity criteria fulfilled:

yes

Interpretation of results:

inherently biodegradable

Conclusions:

In conclusion, on the basis of this present study, FAT 93504/A was found to be biodegradable at 21 % (primary biodegradation) after an incubation time of 28 days.

Executive summary:

The aims of this study are to determine the inherent biodegradability and the BOD5 of FAT 93504/According to the OECD Guideline 302 C (Inherent Biodegradability: Modified MITI Test (II)). A reference substance was used during this experiment in same condition as the test substance. The duration of the test was 28 days. The experiment was done at 25 °C under static conditions. The test volume was 250 ml and it was continuously stirred in the darkness. Test concentration of the test substance was 30 mg/l and the concentration of the reference substance was 100 mg/l. The biodegradation of the test substance after 28 days is 21 % (primary biodegradation) and the BOD5 after 5 days is 0 mg O2/g. The biodegradation of sodium benzoate (reference substance) after 14 days is 88 %.

Description of key information

The test substance can be considered to be inherently biodegradable. The biodegradation of the test substance after 28 days is 21 %.

Key value for chemical safety assessment

Biodegradation in water:

inherently biodegradable

Additional information

A study was performed to determine the inherent biodegradability and the BOD5 of FAT 93504/A according to the OECD Guideline 302 C (Inherent Biodegradability: Modified MITI Test (II)). The biodegradation of the test substance after 28 days is 21 % and the BOD5 after 5 days is 0 mg O2/g.