4-(butoxymethyl)-2-methoxyphenol

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:

September - November 2009

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)

Qualifier:

according to guideline

Guideline:

EU Method C.4-D (Determination of the "Ready" Biodegradability - Manometric Respirometry Test)

GLP compliance:

yes (incl. QA statement)

Oxygen conditions:

aerobic

Inoculum or test system:

activated sludge, non-adapted

Details on inoculum:

Activated sludge from biological sewage refinery „Pszczyna” in Pszczyna was collected in quantities of about 5 dm3 in plastic vessels. Activated sludge was immediately transported to laboratory in a period of time shorter than 60 minutes. After transport the activated sludge was sieved using a sieve with diameter of meshes equal 1 millimeter. Decantation lasted at least 60 minutes followed by draining of the supernatant. The remaining sediment was added into 10 L vessels where it was washed intensively with tap water. The sediment was intensively agitated with a glass rod and the sludge was allowed to settle for 60 minutes. The supernatant was drawed off and rinsed. The supernatant was rinsed four times until foam from the surface of water disappeared. After the last rinse the sediment was decanted in a period of time not shorter than 1h, the supernatant was drained and remaining sediment was carefully poured from the vessel to a tall beaker with a volume of 5 L so that 3/4 of sediment volume was transferred. Mineral medium was added to vessels containing the sediment, so a final volume of 4.5 L was obtained. The sediment was intensively agitationed, and the sludge was allowed to settle for 30 minutes, the supernatant was poured out. This operations were repeated three times. When the mineral medium was added for the third time the content of vessel was agitationed and intensively aerated to caused circulation of sludge suspended solids in volume of vessel. The compressed air came from aquarius aeration pump and was inflated through a cotton wool strainer and glass frit.

Duration of test (contact time):

28 d

Initial conc.:

40 mg/L

Based on:

test mat.

Parameter followed for biodegradation estimation:

O2 consumption

Details on study design:

TEST CONDITIONS
- Composition of medium: according to OECD Guideline 301
- Solubilising agent used: no
- Test temperature: 22°C
- pH: 6.82 - 7.37
- pH adjusted: no
- Aeration of dilution water: no
- Suspended solids concentration: 15 mg/dm³

TEST SYSTEM
- Culturing apparatus: glass vessels of 5.0L and 10.0L volume
- Number of culture flasks/concentration: 2
- Measuring equipment: Sensomat-Measurement-System from AQUALYTIC, Germany
- Conditions: dark

SAMPLING
- Sampling frequency: after 1, 3, 5, 7, 14, 21, 23, 25, 27 and 28 days

CONTROL AND BLANK SYSTEM
- Inoculum blank: containing only inoculum (2 flasks)
- Procedure control: containing reference compound and inoculum (1 flask)
- Toxicity control: containing test substance, reference compound and inoculum (1 flask)

Reference substance:

acetic acid, sodium salt

Key result

Parameter:

% degradation (O2 consumption)

Value:

60.75

St. dev.:

0.7

Sampling time:

28 d

Details on results:

The biodegradation of the test item started after 14 days (1.64%) and increased from there on (day 21: 8.11%; day 25: 33.94%). After 28 days of the experiment biodegradation of test material was 60.75%

Results with reference substance:

The biodegradation of the reference substance was 69.94% after 7 days and 79.42% after 28 days of the experiment.

Validity criteria fulfilled:

yes

Interpretation of results:

readily biodegradable

Conclusions:

Within the test period of 28 days, a degradation of 60.75% was determined for the test item.

Executive summary:

The biodegradation of the test item was determined in a manometric respirometry test according to OECD 301F. The test substance is suspended in test medium, inoculated with activated sludge of a biological sewage refinery and incubated for 28 days under aerobic conditions in the dark at 22°C. During this period, the biodegradation of the test substance is determined on the basis of O2 consumption. Within the test period of 28 days, a degradation of 60.75% was determined.

Description of key information

The test item is readily biodegradable: OECD 301F, 60.75 % degradation after 28 days

Key value for chemical safety assessment

Biodegradation in water:

readily biodegradable

Additional information

The biodegradation of the test item was determined in a manometric respirometry test according to OECD 301F. The test substance was suspended in test medium, inoculated with activated sludge of a biological sewage refinery and incubated for 28 days under aerobic conditions in the dark at 22°C. During this period, the biodegradation of the test substance was determined on the basis of O2 consumption. Within the test period of 28 days, a degradation of 60.75% was determined.