Bis(cyclohexyl)ammonium(2S)-2-{[(benzyloxy)carbonyl]amino}-3,3-dimethylbutanoate

Biodegradation in water: screening tests

Administrative data

Endpoint:

biodegradation in water: ready biodegradability

Type of information:

experimental study

Adequacy of study:

key study

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: GLP guideline study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2007

Report date:

2007

Materials and methods

Test guideline

Test guideline 1

Qualifier:

according to guideline

Guideline:

OECD Guideline 301 B (Ready Biodegradability: CO2 Evolution Test)

Test guideline 2

Qualifier:

according to guideline

Guideline:

EU Method C.4-C (Determination of the "Ready" Biodegradability - Carbon Dioxide Evolution Test)

GLP compliance:

yes (incl. QA statement)

Test material

Test material information

Constituent 1

Reference substance name:

-

EC Number:

478-250-9

EC Name:

-

Cas Number:

62965-37-1

Molecular formula:

C26H42N2O4

IUPAC Name:

(2S)-2-{[(benzyloxy)carbonyl]amino}-3,3-dimethylbutanoic acid; N-cyclohexylcyclohexanamine

Study design

Oxygen conditions:

aerobic

Inoculum or test system:

activated sludge, domestic (adaptation not specified)

Details on inoculum:

A sample of activated sludge was collected from the aeration tank at Worlingworth sewage treatment works, which treats predominantly domestic
waste. Aliquots (25 ml) of a homogenised sample were filtered through dried (approximately 105°C) and pre-weighed Whatman GF/C filter papers.
The filters were dried for at least one hour, allowed to cool and re-weighed. The solids level in the sludge was determined and then an appropriate
volume used to inoculate control and test vessels to give a final suspended solids concentration of 30 mg/l

Duration of test (contact time):

29 d

Parameter followed for biodegradation estimation

Parameter followed for biodegradation estimation:

CO2 evolution

Details on study design:

Mean cumulative CO2 production by the mixtures containing VRT-126017 dcha was equivalent to 10% of the TCO2 after approximately 7 days and 54% by the end of the test on Day 29.
The pH of each test and control mixture was 7.6 at the start of the test and ranged from 7.4 to 7.6 at the end.
The rate of air flow during the test ranged from 40 to 75 ml/minute.
The temperature of a three-litre volume of water held under the test conditions ranged from 21.7°C to 22.7°C during the test period

Reference substance

Reference substance:

benzoic acid, sodium salt

Results and discussion

% Degradation

% Degradation 1

Parameter:

% degradation (CO2 evolution)

Value:

0

Sampling time:

2 d

% Degradation 2

Parameter:

% degradation (CO2 evolution)

Value:

13

Sampling time:

8 d

% Degradation 3

Parameter:

% degradation (CO2 evolution)

Value:

47

Sampling time:

17 d

% Degradation 4

Parameter:

% degradation (CO2 evolution)

Value:

53

Sampling time:

28 d

% Degradation 5

Parameter:

% degradation (CO2 evolution)

Value:

54

Sampling time:

29 d

BOD5 / COD results

Results with reference substance:

23 % degradation after 2 d
45 % degradation after 4 d
61 % degradation after 6 d
68 % degradation after 8 d
71 % degradation after 9 d
73 % degradation after 10 d
75 % degradation after 13 d
78 % degradation after 17 d
81 % degradation after 22 d
84 % degradation after 28 d
85 % degradation after 29 d

Applicant's summary and conclusion

Conclusions:

The mean cumulative CO2 production by mixtures containing VRT-126017 dcha at 9.4 mgC/l was equivalent to 10% of the TCO2 after approximately 7 days and 54% by the end of the test on Day 29. The test item cannot considered to be readily biodegradable.