[No public or meaningful name is available]

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:

2019-04-17 to 2019-05-16

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)

Version / remarks:

1992

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Oxygen conditions:

aerobic

Inoculum or test system:

activated sludge, domestic, non-adapted

Duration of test (contact time):

28 d

Initial conc.:

52.03 mg/L

Based on:

ThOD

Initial conc.:

28.91 mg/L

Based on:

test mat.

Parameter followed for biodegradation estimation:

O2 consumption

Details on study design:

Test item vessels containing test item with a concentration of 28.91 mg test item /L (2 replicates);
Process control vessels containing reference item with a concentration of 31.25 mg reference item /L (2 replicates);
Toxicity control vessels containing test item with a concentration of 28.96 mg test item /L and reference item with a concentration of 31.63(1 replicate);
Blank control vessels containing only inoculated mineral medium without test item (2 replicates).

Reference substance:

benzoic acid, sodium salt

Preliminary study:

No

Key result

Parameter:

% degradation (O2 consumption)

Value:

74

Sampling time:

28 d

Results with reference substance:

Biodegradation of the reference substance reached 60% after 4 days, 84.8% after 28 days.

Validity criteria fulfilled:

yes

Interpretation of results:

readily biodegradable

Conclusions:

The test item was readily biodegradable.

Executive summary:

The ready biodegradability of the test item was performed according to OECD guideline 301F (manometric respirometry test) and GLP. The test was conducted with unacclimatised sewage microorganism by measuring oxgen consumption over a 28-day test period. The test concentration was set at 28.91 mg test item/L (equivalent to 52.03 mg/L as Theoretical Oxygen Demand). Sodium benzoate was used as positive reference substance. The test item was not inhibitory to microorganism under the conditions of this test. The percentage biodegradation of the test item over 28 days was 74.0% and the 10-day window was met (5-15 day).The test item was determined to be readily biodegradable under test conditions.

Description of key information

A study of the ready biodegradability of the test item was performed according to OECD guideline 301F (manometric respirometry test) and GLP. The test was conducted with unacclimatised sewage microorganism by measuring oxgen consumption over a 28-day test period. The test concentration was set at 28.91 mg test item/L (equivalent to 52.03 mg/L as Theoretical Oxygen Demand). Sodium benzoate was used as positive reference substance. The test item was not inhibitory to microorganism under the conditions of this test. The percentage biodegradation of the test item over 28 days was 74.0% and the 10-day window was met (5-15 day).The test item was determined to be readily biodegradable under test conditions.

 

Key value for chemical safety assessment

Biodegradation in water:

readily biodegradable

Type of water:

freshwater