4-trans-propenylveratrole

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 1999-11-23 to 1999-12-22

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Remarks:

This study was performed according to OECD Guideline 301F with GLP compliance. All validity criteria were fulfilled and no deviations were observed.

Qualifier:

according to guideline

Guideline:

OECD Guideline 301 F (Ready Biodegradability: Manometric Respirometry Test)

Deviations:

no

Principles of method if other than guideline:

Not applicable

GLP compliance:

yes

Remarks:

Statement of compliance with GLP in date of 2000-01-10

Specific details on test material used for the study:

No additional information

Oxygen conditions:

aerobic

Inoculum or test system:

activated sludge, domestic (adaptation not specified)

Details on inoculum:

Fresh activated sludge from a biological waste water treatment plant treating predominantly domestic sewage (City of Geneva, Aire) was used.
The sludge is collected in the morning, washed three times in the mineral medium (by centrifuging at 1000 g for 10 minutes, discarding the supernatant and resuspending in mineral medium) and kept aerobic until being used on the same day,
Concentration of sludge: 4.355 g/L (dry weight of suspended solids); to obtain a concentration of 30 mg/L (dry weight) in a 1000 mL flask, 6.89 mL of sludge is needed (inoculum).

Duration of test (contact time):

28 d

Initial conc.:

100 mg/L

Based on:

test mat.

Parameter followed for biodegradation estimation:

O2 consumption

Details on study design:

TEST CONDITIONS
- Composition of medium: compliant with recommendations of TG on mineral medium; the pH is measured and if necessary adjusted to 7.4 ± 0.2 with phosphoric acid or potassium hydroxide.
- Solubilising agent (type and concentration if used): None
- Test temperature: 22 °C
- CEC (meq/100 g): No data
- Aeration of dilution water: No data
- Suspended solids concentration: 30 mg/L
- Continuous darkness: No data
- Water: The water used during this study is deionised water containing less than 10 mg/L dissolved organic carbon.

TEST SYSTEM
- Culturing apparatus: Test flasks of the BI-1000
- Number of culture flasks/concentration: 2
- Measuring equipment: The respirometer used during this study is a BI-1000, made by BIOSCIENCE Inc. Bethlehem, PA, USA.
- Test performed in closed vessels: Yes
- Test performed in open system: No

CONTROL AND BLANK SYSTEM
- Inoculum blank: Yes
- Procedure control: Yes with the reference substance
- Toxicity control: Yes

Reference substance:

benzoic acid, sodium salt

Remarks:

100 mg/L

Preliminary study:

None

Test performance:

The oxygen consumption of each flask is automatically recorded by the BI-1000 during the whole test duration. Correct temperature and stirring are regularly checked visually. At the end of the test period (normally 28 days), the pH of each flask is measured again.

Key result

Parameter:

% degradation (O2 consumption)

Value:

100

Sampling time:

28 d

Remarks on result:

other: >60% within the 10d window

Details on results:

Test material underwent 100 % biodegradation after 28 days under the test conditions. Biodegradation started on day 2 and reached 94 % at the end of the 10 day window (days 2 to 12).
Test material at 100 mg/L was not inhibitory to the micro-organisms.

Results with reference substance:

Degradation of sodium benzoate exceeded 40 % after 7 days and 65 % after 14 days: the activity of the inoculum is thus verified and the test is considered as valid.

Table 5.2.1/2: Test substance - Biological Oxygen Demand (BOD, mg O2/L, adjusted to nominal concentrations)

		Days:	2	7	12	15	21	28
BOD sludge	1^stflask	B1	11.0	26.0	37.0	44.0	46.0	51.0
	2^ndflask	B2	10.0	23.0	34.0	39.0	41.0	46.0
	mean	B	10.5	24.5	35.5	41.5	43.5	48.5
BOD test substance	1^stflask	C1	116.5	251.0	264.0	278.0	289.9	292.9
	2^ndflask	C2	123.3	248.7	262.7	275.7	288.7	290.7
	1^stflask corr.	C1-B	106.0	226.5	228.5	236.5	246.4	244.4
	2^ndflask corr.	C2-B	112.8	224.2	227.2	234.2	245.2	242.2
% biodegradation	1^stflask	D1	44	94	94	98	102	101
	2^ndflask	D2	47	93	94	97	101	100
	mean	D	45	93	94	97	102	101

 

Calculations:

B = (B1 + B2) / 2

DI = 100 * (C1 - B) / ThOD * [S]

D2 = 100 * (C2 - B) / ThOD * [S]

D = (DI + D2)/2

[S] : Initial test substance concentration (mg/L)  Theoretical Oxygen Demand (ThOD) : 2.42 mg O2 / mg

Validity criteria fulfilled:

yes

Interpretation of results:

readily biodegradable

Conclusions:

The test material underwent 100 % biodegradation after 28 days under the test conditions. The 10-day window criterion was also fulfilled. Thus, the test item should be regarded as readily biodegradable according to this test. In addition, no toxic effects of the test material were observed to microorganisms at the test concentration.

Executive summary:

The ready biodegradability of the test material has been determined by the Manometric Respirometry Test according to the OECD Guideline No. 301F with GLP compliance.

A nominal concentration of test material (100 mg/L) was introduced into the system.

 

Test material at 100 mg/L was not inhibitory to the micro-organisms. The test material underwent 100 % biodegradation after 28 days under the test conditions. Biodegradation started on day 2 and reached 94 % at the end of the 10 day window (days 2 to 12). Degradation of sodium benzoate exceeded 40 % after 7 days and 65 % after 14 days: the activity of the inoculum is thus verified and the test is considered as valid.

 

Under the conditions of this test, the test item should be regarded as readily biodegradable.

Description of key information

OECD Guideline 301F, GLP, key study, validity 1:

100% biodegradation after 28 days within the 10-day window.

Readily biodegradable.

Non-toxic to microorganisms up to 100 mg/L.

Key value for chemical safety assessment

Biodegradation in water:

readily biodegradable

Additional information

One valid key study is available (Givaudan, 2000), to assess the ready biodegradation of the registered substance.

This study was performed on the registered substance according to OECD Guideline 301F and was GLP compliant. The test substance at 100 mg/L was inoculated with activated sludge from a biological wastewater treatment plant treating predomantly domestic sewage. The degradation of the test substance was assessed by the determination of the oxygen consumption. The test substance undergoes 100% biodegradation within a 28-day exposure period. Biodegradation started on day 2 and reached 94% at the end of the 10 day window (days 2 to 12). Therefore, the test substance is considered readily biodegradable. In the toxicity control, containing both the test substance and the reference substance (sodium benzoate), the test substance had no inhibitory effect on the activity of activated sludge microorganisms at the tested concentration of 100 mg/L. In the procedure controls, the degradation of the reference substance exceeds 40% after 7 days and 65% after 14 days, thus confirming suitability of the activated sludge.