Bis-biphenyl-4-yl-(9,9‘-spirobifluoren-4-yl)-amine

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:

2015-08-08 til 2019-01-15

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

OECD Guideline 301 F (Ready Biodegradability: Manometric Respirometry Test)

Principles of method if other than guideline:

NA

GLP compliance:

yes

Oxygen conditions:

aerobic

Inoculum or test system:

activated sludge, domestic, adapted

Details on inoculum:

Sludge collection: a fresh sample of activated sludge was collected on Oct 11, 2018 from the aeration tank ofthe Long Hua Wastewater Treatment Plant in Shanghai
which treats predominantly domestic sewage. The activated sludge was kept by aeration until used (non-aeration during transport from the wastewater treatment plant
to the laboratory was kept to a minimum). Sludge treatment: When back to the laboratory, the sludge was washed with mineral medium.
After centrifugation, the supernatant was decanted. This procedure was repeated three times (4000rpm, 4°C, centrifuge 20 minutes). Then, 0.416g of the concentrated sludge was weighed, dried at 105°C for 1 h and then measured by moisture meter for 1 h to determine the dry weight. The dry weight of concentrated sludge was 6.73%.

Sludge suspension: According to the dry weight, 43.58 g of concentrated sludge was calculated and suspended in 1 L mineral medium to yeild a concentration of 3g suspended solids/L. The final concentration of the activated sludge in the test medium was 30 mg/L.

Duration of test (contact time):

28 d

Initial conc.:

18 mg/L

Based on:

test mat.

Remarks:

final concentration was clearly above water solubility

Parameter followed for biodegradation estimation:

O2 consumption

Reference substance:

benzoic acid, sodium salt

Parameter:

% degradation (O2 consumption)

Value:

0

Sampling time:

28 d

Details on results:

Under the test conditions no biodegradation of test item could be observed.
The percentage degradation did not exceed 60 % within the 10-day window and after 28 days of incubation.
The test item is considered not readily biodegradable.
The reference Item sodium sodium benzoate was sufficiently degraded to 72 % and 75 % after 14 and 28 days, respectively. The percentage degradation (> 60 % after 14 days) of the reference item confirms the suitability of the used activated sludge inoculum.

Results with reference substance:

The reference Item sodium sodium benzoate was sufficiently degraded to 72 % and 75 % after 14 and 28 days, respectively. The percentage degradation of the reference item confirms the suitability of the used activated sludge inoculum.

Validity criteria fulfilled:

yes

Interpretation of results:

under test conditions no biodegradation observed

Conclusions:

Under the test conditions no biodegradation of test item could be observed. The percentage degradation did not exceed 60 % within the 10-day window and after 28 days of incubation. The test item is considered not readily biodegradable.

Executive summary:

In this OECD 301F Assay the results show no biodegradation of test item.

The percentage degradation did not exceed 60 % within the 10-day window and after 28 days of incubation.

The test item is considered not readily biodegradable.

The reference Item sodium sodium benzoate was sufficiently degraded to 72 % and 75 % after 14 and 28 days, respectively. The percentage degradation of the reference item confirms the suitability of the used activated sludge inoculum.

The toxicity control showed 53 and 55 % degradation after 14 and 28 days respectively. According to the test guidelines the test item can thus be assumed to be not inhibitory on the activated sludge micro organisms because degradation was > 25% within 14 days.

Description of key information

OECD 301F: not readily biodegradable

Key value for chemical safety assessment

Biodegradation in water:

under test conditions no biodegradation observed

Type of water:

freshwater