Quinazolin-4(1H)-one

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:

From 2000-03-30 to 2000-04-27

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

OECD Guideline 301 B (Ready Biodegradability: CO2 Evolution Test)

Version / remarks:

1993

Deviations:

no

GLP compliance:

yes

Specific details on test material used for the study:

Batch No.: Partie 1
Purity: 68.3%

Oxygen conditions:

aerobic

Inoculum or test system:

activated sludge, domestic, non-adapted

Details on inoculum:

- Source of inoculum/activated sludge: laboratory wastewater plant treating municipal sewage
- Laboratory culture:
- Method of cultivation:
- Storage conditions:
- Storage length:
- Preparation of inoculum for exposure:
- Pretreatment:
- Concentration of sludge:
- Initial cell/biomass concentration: dry substance 30 mg/L
- Water filtered: yes/no
- Type and size of filter used, if any:

Duration of test (contact time):

28 d

Initial conc.:

47.6 mg/L

Based on:

test mat.

Parameter followed for biodegradation estimation:

DOC removal

Details on study design:

Mixtures of the test substance, a defined inorganic medium and a non pre-adapted inoculum are incubated and aerated at room temperature up to 28 days . The biologically produced carbon dioxide is trapped and measured.

Reference substance:

aniline

Preliminary study:

- TOC [mg/g]: 422
- DOC [mg/g]: 429
- TC [mg/g]: 430, referring to the original test substance
- TC [mg/g]: 657, referring to the dry residue

Key result

Parameter:

% degradation (CO2 evolution)

Value:

74

Sampling time:

28 d

Details on results:

- Duration of adaptation phase (days): 13
- Duration of degradation phase (days): 15
- Degradation of the test subst . at the end of the ten-day window (% CO2/ThCO2): 70-80
- Degradation degree of the test subst . at the end of the test (% CO2/ThCO2): 70-80
- Elimination of the test substance after 28 days (%DOC): 90-100
- Degradation degree of the reference substance after 14 days (% CO2/ThCO2): 70-80
- Degradation degree in the inhibition control after 14 days (% CO2/ThCO2): 60-70

Validity criteria fulfilled:

yes

Interpretation of results:

readily biodegradable

Conclusions:

The test substance is readily biodegradable.

Executive summary:

The Biodegradability of test item was determined in the C02-Evolution Test according to OECD Guideline 301 B.

The test concentration was 47.6 mg/L equivalent to 20 mg/L TOC.Activated sludge from laboratory wastewater plant treating municipal sewage was used as inoculum. Concentration of dry substance was 30 mg/L.

The Biodegradation degree (CO2 to ThCO2) after 28 days was 70-80 % and DOC-elimination of the test substance after 28 days was 90-100 %.

Therefore, the test substance is readily biodegradable.

Description of key information

One CO2-Evolution Test (OECD Guideline 301 B) was available, the Biodegradation degree (CO2 to ThCO2) after 28 days was 70-80 % and DOC-elimination of the test substance after 28 days was 90-100 %. The test substance is readily biodegradable.

Key value for chemical safety assessment

Biodegradation in water:

readily biodegradable

Type of water:

freshwater