Reaction mass of 3-phenoxybenzyl (1R,3R)-2,2-dimethyl-3-(2-methylprop-1-en-1-yl)cyclopropanecarboxylate and 3-phenoxybenzyl (1R,3S)-2,2-dimethyl-3-(2-methylprop-1-en-1-yl)cyclopropanecarboxylate (4:1)

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:

2002

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: GLP study according to guideline without deficiencies.

Qualifier:

according to guideline

Guideline:

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

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Oxygen conditions:

aerobic

Inoculum or test system:

sewage, predominantly domestic (adaptation not specified)

Details on inoculum:

Diluted activated sludge was used as inoculum.

Duration of test (contact time):

28 d

Initial conc.:

100 mg/L

Based on:

ThOD/L

Parameter followed for biodegradation estimation:

O2 consumption

Parameter:

% degradation (O2 consumption)

Value:

0 - <= 1

Sampling time:

6 d

Parameter:

% degradation (O2 consumption)

Value:

0 - <= 2

Sampling time:

9 d

Parameter:

% degradation (O2 consumption)

Value:

0 - <= 3

Sampling time:

15 d

Parameter:

% degradation (O2 consumption)

Value:

0 - <= 4

Sampling time:

17 d

Key result

Parameter:

% degradation (O2 consumption)

Value:

0 - <= 5

Sampling time:

26 d

Results with reference substance:

The percent biodegradation of the reference item sodium benzoate was calculated based on the theoretical oxygen demand of 1.67 mg O2/mg (ThOD). In the procedure controls, the reference item was degraded by an average of 85% by exposure Day 14, thus confirming suitability of activated sludge. At the end of the test (day 28), the reference item was degraded by an average of 93%.

Validity criteria fulfilled:

yes

Interpretation of results:

not readily biodegradable

Conclusions:

The Biochemical Oxygen Demand (BOD) of d-Phenothrin in the test media was within the range of the inoculum controls.
According to the test guidelines, the test item had no inhibitory effect on activated sludge microorganism because the biodegradation rate in the toxicity control was >25% within 14 days.
The validity criteria can be considered as partially fulfilled (see validity criteria summarized in Table A7_1_1_2_1-5). Therefore, the manometric respirometry test on ready biodegradability of d-Phenothrin is valid. The biochemical oxygen demand (BOD) of the test item d-Phenothrin in the test media was in the normal range found for the inoculum controls. Consequently, d-Phenothrin was found to be not biodegradable under the test conditions within 28 days.

Executive summary:

d-Phenothrin was found to be not biodegradable under the test conditions within 28 days.

Description of key information

d-Phenothrin was found to be not biodegradable under the test conditions within 28 days.

Key value for chemical safety assessment

Biodegradation in water:

under test conditions no biodegradation observed

Type of water:

freshwater