Acetamide, N-(4-fluorophenyl)-2-hydroxy-N-(1-methylethyl)-

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:

EU Method C.4-E (Determination of the "Ready" Biodegradability - Closed Bottle Test)

GLP compliance:

yes (incl. QA statement)

Oxygen conditions:

aerobic

Inoculum or test system:

activated sludge, domestic (adaptation not specified)

Details on inoculum:

- Type: aquatic mixed population of microorganisms (activated sludge)
- Origin: secondary effluent of a domestic sewage treatment plant (Wupper area water authority)
- sampling date: 18.02.1994
- Pre-Treatment: None

Duration of test (contact time):

28 d

Initial conc.:

4.2 mg/L

Based on:

test mat.

Details on study design:

A measured volume of mineral medium containing a known concentration of the test substance and inoculum was incubated under aerobic conditions in the dark for 28 d at 20 - 21 °C. The endogenous activity of the inoculum was checked by running parallel blanks with inoculum but without test item. A reference compound (Aniline) was run in parallel to check the operation of the procedures. A toxicity control was run in duplicate.
Degradation was followed by the determination of oxygen uptake and measurements were taken at frequent intervals to allow the identification of the beginning and end of biodegradation.

Reference substance:

aniline

Remarks:

purity: 99.5 %

Parameter:

% degradation (O2 consumption)

Value:

2

Sampling time:

7 d

Parameter:

% degradation (O2 consumption)

Value:

3

Sampling time:

14 d

Parameter:

% degradation (O2 consumption)

Value:

1

Sampling time:

21 d

Parameter:

% degradation (O2 consumption)

Value:

4

Sampling time:

28 d

Details on results:

The calculation of degradation was done under the presumption of no nitrogen oxidation.

Results with reference substance:

After 14 d more than 80 % of the reference substance aniline were degraded.

Validity criteria fulfilled:

yes

Interpretation of results:

under test conditions no biodegradation observed

Conclusions:

A biodegradation of 4% was determined for the test substance after 28 d.

Executive summary:

A study was conducted in accordance with the Council Regulation (EC) Method C.4-E “Closed Bottle Test“.The test item was dissolved in a mineral medium, which was inoculated with a mixed population of aquatic microorganisms and incubated under aerobic conditions in the dark at 20 - 21 °C for 28 days.The endogenous activity of the inoculum was checked by running parallel blanks with inoculum but without test item. A reference compound (Aniline) was run in parallel to check the operation of the procedures. A toxicity control was run in duplicate.

Degradation was followed by the determination of oxygen uptake and measurements were taken at frequent intervals to allow the identification of the beginning and end of biodegradation. A biodegradation of 4% was determined for the test substance after 28 d.

Description of key information

A study was conducted in accordance with the Council Regulation (EC) Method C.4-E “Closed Bottle Test“.The test item was dissolved in a mineral medium, which was inoculated with a mixed population of aquatic microorganisms and incubated under aerobic conditions in the dark at 20 - 21 °C for 28 days.The endogenous activity of the inoculum was checked by running parallel blanks with inoculum but without test item. A reference compound (Aniline) was run in parallel to check the operation of the procedures. A toxicity control was run in duplicate.

Degradation was followed by the determination of oxygen uptake and measurements were taken at frequent intervals to allow the identification of the beginning and end of biodegradation. A biodegradation of 4% was determined for the test substance after 28 d.

Key value for chemical safety assessment

Biodegradation in water:

under test conditions no biodegradation observed

Type of water:

freshwater