Cyclopentane, methoxy-

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:

17 October 2001 - 05 December 2001

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: The study was conducted according to Japanese and OECD test guidelines, and in compliance with GLP, so the data is considered reliable without restriction.

Qualifier:

according to guideline

Guideline:

OECD Guideline 301 C (Ready Biodegradability: Modified MITI Test (I))

Deviations:

no

Qualifier:

according to guideline

Guideline:

other: "Method for Testing the Biodegradability of Chemical Substances by Microorganisms" in "Testing Methods for New Chemical Substances" (July 13, 1974, No. 5, Planning and Coordination Bureau, Environment Agency; No.615 MHW, and No.392, MITI, Japan).

Deviations:

no

GLP compliance:

yes

Specific details on test material used for the study:

- Analytical purity: 99.6%
- Lot/batch No.: 01529

Oxygen conditions:

aerobic

Inoculum or test system:

activated sludge (adaptation not specified)

Details on inoculum:

Sludge was sampled from 10 locations (a mixture of sewage treatment plants, rivers, lakes and bays) in Japan in September 2001. For city sewage, return sludges from sewage plants were collected; for rivers, lakes and sea locations (bays), surface water and surface soil which was in contact with the atmosphere were collected.

Preparation ofactivated sludge:
Activated sludge was prepared as follows to maintain its uniformity.
The filtrate (5 L) of the supernatant of the activated sludge (The activated sludge cultivated the mixed filtrate (10 L) of the supernatant of sludge collected at the ten locations) cultivated about for 3 months was mixed with the mixed filtrate (5 L) of the supernatant of a sludge collected newly at each location. The mixed filtrate (10 L) was aerated (Prefiltered open air was used.) after the pH value of the mixture was adjusted to 7.0±1.0.

Duration of test (contact time):

28 d

Initial conc.:

100 mg/L

Based on:

test mat.

Parameter followed for biodegradation estimation:

O2 consumption

Parameter followed for biodegradation estimation:

test mat. analysis

Remarks:

Residual test material concentration determined by GC at the end of the contact period.

Details on study design:

TEST CONDITIONS
- Test temperature: 25±1°C
- pH: 7.0
- pH adjusted: yes
- Suspended solids concentration: 30 mg/L
- Continuous darkness: no
- Other:

TEST SYSTEM
- Number of culture flasks/concentration: 3
- Details of trap for CO2 and volatile organics if used: Soda lime

SAMPLING
- Sampling frequency: Automatically recorded using a data sampler

CONTROL AND BLANK SYSTEM
- Inoculum blank: Yes

Reference substance:

aniline

Parameter:

% degradation (O2 consumption)

Value:

ca. 2

Sampling time:

28 d

Details on results:

Points of degradation plot (test substance): 1 % degradation after 7 d 2 % degradation after 14 d 2 % degradation after 21 d 2 % degradation after 28 d

Results with reference substance:

Points of degradation plot (reference substance):
77 % degradation after 7 d
106 % degradation after 14 d
112 % degradation after 21 d
113 % degradation after 28 d

Validity criteria fulfilled:

yes

Interpretation of results:

under test conditions no biodegradation observed

Description of key information

OECD Guideline 301C, Modified MITI test: not readily biodegradable.

Key value for chemical safety assessment

Biodegradation in water:

under test conditions no biodegradation observed

Type of water:

freshwater

Additional information

A ready biodegradability screening test was conducted (Kurume Laboratory, 2001) to assess the potential for the substance to be degradaed by microorganisms over a 28 -day period. The study was performed according to OECD test guideline 301C (the modified MITI test) and Japanese test guidelines, and in compliance with GLP.

The average percentage biodegradation measured by biochemical oxygen demand (BOD) over the 28 -day exposure period was 2%, and so the substance was concluded not to be readily biodegradable under the test conditions.