Diphenyl(2,4,6-trimethylbenzoyl)phosphine oxide

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

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)

GLP compliance:

yes

Oxygen conditions:

aerobic

Inoculum or test system:

activated sludge, domestic, non-adapted

Details on inoculum:

- Source of inoculum/activated sludge (e.g. location, sampling depth, contamination history, procedure): Municipal activated sludge from laboratory wastewater treatment plants fed with municipal sewage.
- Concentration of sludge: 30 mg/l

Duration of test (contact time):

28 d

Initial conc.:

100 mg/L

Based on:

test mat.

Parameter followed for biodegradation estimation:

O2 consumption

Details on study design:

TEST CONDITIONS
- Composition of medium: 240 ml inorganic medium, 10 mL inoculum, 100 mg/L test substance
- Test temperature: room temperature
- pH: 7.3 - 7.7
- pH adjusted: no



TEST SYSTEM
- Culturing apparatus: Sapromat
- Number of culture flasks/concentration: 7


SAMPLING
- Sampling frequency: daily


CONTROL AND BLANK SYSTEM
- Inoculum blank: yes
- Abiotic sterile control: yes
- Toxicity control: yes

Reference substance:

aniline

Parameter:

% degradation (O2 consumption)

Value:

0 - 10

Sampling time:

28 d

Details on results:

Kinetic of control substance (in %):
= 70 - 80 after 14 day(s)

Interpretation of results:

other: The test substance is poorly biodegradable and not readily biodegradable according to OECD criteria.

Key value for chemical safety assessment

Biodegradation in water:

under test conditions no biodegradation observed

Type of water:

freshwater

Additional information

The substance was found to be not readily biodegradable in a standard OECD 301F respirometric test. At a test concentration of 100 mg/L the biodegradation degree (BOD of ThOD) was 0 – 10%.