1,8-bis(phenylthio)anthraquinone

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

Study period:

1999

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:

not specified

GLP compliance:

no

Specific details on test material used for the study:

SOURCE OF TEST MATERIAL
- Source and lot/batch No.of test material: Div. Lab. Vers.
- Expiration date of the lot/batch: 11/2003

STABILITY AND STORAGE CONDITIONS OF TEST MATERIAL
- Storage condition of test material: room temperature
- Solubility and stability of the test substance in the solvent/vehicle: <2 g/l [in water]

Oxygen conditions:

aerobic

Inoculum or test system:

activated sludge (adaptation not specified)

Details on inoculum:

Sludge: 100 mg/L suspended solids
Waste water plant: ARA-PRO RHENO Basel communal

Duration of test (contact time):

28 d

Initial conc.:

30 mg/L

Based on:

test mat.

Parameter followed for biodegradation estimation:

O2 consumption

Details on study design:

ThOD: 2.42 mg O2/mg
Concentration: 30 mg/L test substance in test medium

Reference substance:

other: yes (but name was not cited in the study report)

Parameter:

% degradation (test mat. analysis)

Value:

0

Sampling time:

28 d

Remarks on result:

other: Std deviation not specified

Parameter:

BOD5

Value:

0 mg O2/g test mat.

Results with reference substance:

Biodegradation of the reference substance after 14 d = 84 %

Validity criteria fulfilled:

yes

Interpretation of results:

not inherently biodegradable

Conclusions:

The test substance was not considered to be inherently biodegradable.

Executive summary:

A study was performed to assess the inherent biodegradability of the test substance FAT 93450/A (of ca. 96 % purity) in an aerobic aqueous medium according to OECD Guideline 302 C.

The mean value of the biodegradation of test substance after 28 d was 0 %. Hence, FAT 93450/A can be considered to be not inherently biodegradable.

The biochemical oxygen demand (BOD5) after 5 d was 0 mg O2/g. Comparing this with the COD of FAT 93450/A of 2018 mg O2/g, the BOD5/COD ratio is 0. Hence, FAT 93450/A can also be considered to be not readily biodegradable.

Description of key information

FAT 93450/A is neither readily nor inherently biodegradable.

Key value for chemical safety assessment

Biodegradation in water:

under test conditions no biodegradation observed

Type of water:

freshwater

Additional information

An inherent biodegradation study with FAT 93450/A (of ca. 96 % purity) was performed in an aerobic aqueous medium according to OECD Guideline 302C. The mean value of the biodegradation of test substance after 28 d was 0 %, while the reference substance after 14 d was biodegraded as 84 %. The biochemical oxygen demand (BOD5) after 5 d was 0 mg O2/g. The COD of FAT 93450/A was found to be 2018 mg O2/g in a study conducted according to DIN 38409 -H 41. Since the BOD5 after 5 days was zero, the BOD5/COD quotient is mathematically not defined. Under the study conditions, the test substance was not considered to be neither readily nor inherently biodegradable.