2,4,6,8-tetramethyl-1,3,5,7-tetraoxacyclooctane

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:

August 2007 - January 2008

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)

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Specific details on test material used for the study:

- Name: META Metaldehyde techn.
- Molecular weight: 176.2 g/mol
- Expiration date: 10-Jul-2009
- Analysis date: 11-Jul-2006
- Appearance: white powder
- Storage conditions:4 to 8°C

Oxygen conditions:

aerobic

Inoculum or test system:

sewage, predominantly domestic, non-adapted

Details on inoculum:

Prior to use samples of activated sludge from the municipal sewage plant at Taunusstein-Bieidenstadt dealing with predominantly domestic sewages was washed
twice with mineral nutrient solution of the "Manometric-Respirometry-Test" to eliminate organic components and carbonates from the sludge. After resolution with mineral nutrient medium the sludge was homogenised in a "Waring Blender" at low speed for 2 minutes and then filtered through a cotton filter previously carefully rinsed with deionised water. The filtrate was used as inoculum (10 ml/L corresponding to 1% of the final volume of the test solution) on the same day of preparation. The dry matter content of that inoculum was 21.7 mg/L (corresponding to 0.2 mg/L in the final test solution).

Duration of test (contact time):

28 d

Initial conc.:

100 mg/L

Based on:

test mat.

Parameter followed for biodegradation estimation:

DOC removal

Details on study design:

standard test design following OECD 301F

Reference substance:

benzoic acid, sodium salt

Preliminary study:

no pretest performed

Test performance:

The study was conducted with the test item, reference substance and toxicity control

Key result

Parameter:

% degradation (O2 consumption)

Value:

2.8

Sampling time:

28 d

Details on results:

Based on the results of a toxicity control (containing both the test item and a reference item) the test item can be considered as not inhibitory towards microorganisms at the concentration tested. Regarding the results obtained within this study the test item may be considered "not readily biodegradable". The reference item sodium benzoate was degraded 91% within 28d. The threshold of >= 60% was met within 4.5d (71.5%) of incubation.

Validity criteria fulfilled:

yes

Interpretation of results:

not readily biodegradable

Conclusions:

After 28d, a mean degradation value of 2.8% of the test item was measured. Regarding the results obtained within this study the test item may be considered "not readily biodegradable".

Executive summary:

The test item was tested for biodegradability using the Manometric Respirometry test method according to OECD Guideline 301 F. The degradation process was followed by the oxygen uptake in the test solutions. After 28d a mean degradation

value of 2.8% of the test item was measured. Based on the results of a toxicity control (containing both the test item and a reference item) the test item can be considered as not inhibitory towards microorganisms at the concentration tested.

Regarding the results obtained within this study the test item may be considered "not readily biodegradable". The reference item sodium benzoate was degraded 91% within 28d. The threshold of >= 60% was met within 4.5d (71.5%) of incubation.

pH-values measured within all test solutions at times t0d and t28d were all in the required range of 6-8.5.

Description of key information

The test item was tested for biodegradability using the Manometric Respirometry test method according to OECD Guideline 301 F. After 28d a mean degradation value of 2.8% of the test item was measured. Regarding the results obtained within this study the test item may be considered "not readily biodegradable". The reference item sodium benzoate was degraded 91% within 28d.

Key value for chemical safety assessment

Biodegradation in water:

under test conditions no biodegradation observed

Type of water:

freshwater

Additional information

Source: GLP-report