2-thiazolidinylidenecyanamide

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: Study according to EC guideline.

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

1997

Report date:

1997

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

EU Method C.4-B (Determination of the "Ready" Biodegradability - Modified OECD Screening Test)

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Test material

Test material information

Constituent 1

Reference substance name:

-

EC Number:

427-720-1

EC Name:

-

Cas Number:

26364-65-8

Molecular formula:

C4H5N3S

IUPAC Name:

[(1,3-thiazolidin-2-ylidene)amino]formonitrile

Details on test material:

name: Cyanamide, (4,5-dihydroxy-2-thiazolyl)-
molecular formula: C4 H5 N3 S
molecular weight: 127.2
physical state: solid
analytical purity: 98 %

Study design

Oxygen conditions:

aerobic

Inoculum or test system:

sewage, domestic, non-adapted

Details on inoculum:

- Source of inoculum/activated sludge (e.g. location, sampling depth, contamination history, procedure): effluent of laboratory scale unit receiving
sewage from the south Wupper area water authority
- Method of cultivation: none
- Pretreatment: Separation of coarse particles by filtration
- Concentration of sludge: 0.5 ml/1

Duration of test (contact time):

29 d

Initial test substance concentration

Initial conc.:

19 mg/L

Based on:

DOC

Parameter followed for biodegradation estimation

Parameter followed for biodegradation estimation:

DOC removal

Details on study design:

TEST CONDITIONS
- Composition of medium: mineral medium
- Test temperature: 22°C +/- 2°C

TEST SYSTEM
- Number of culture flasks/concentration: 2

SAMPLING
- Sampling frequency: on day 0, 7, 14, 21, 28 and 29

CONTROL AND BLANK SYSTEM
- Toxicity control: yes

Reference substance

Reference substance:

aniline

Results and discussion

% Degradation

% Degradation 1

Parameter:

% degradation (DOC removal)

Value:

3

Sampling time:

7 d

% Degradation 2

Parameter:

% degradation (DOC removal)

Value:

0

Sampling time:

14 d

% Degradation 3

Parameter:

% degradation (DOC removal)

Value:

1

Sampling time:

21 d

% Degradation 4

Parameter:

% degradation (DOC removal)

Value:

4

Sampling time:

28 d

% Degradation 5

Parameter:

% degradation (DOC removal)

Value:

2

Sampling time:

29 d

BOD5 / COD results

Results with reference substance:

The reference substance degraded to 96% within 29 days.

Any other information on results incl. tables

test substance	% degradation after n days
Flask nr.	0h	7d	14 d	21 d	28 d	29 d
8	0	0	0	1	2	1
9	0	5	0	1	5	3
Mean	0	3	0	1	4	2

reference substance	% degradation after n days
Flask nr.	0h	7d	14 d	21 d	28 d	29 d
3	0	100	89	95	97	96
4	0	98	95	94	95	96
Mean	0	99	92	95	96	96

toxicity control	% degradation after n days
Flask nr.	0h	7d	14 d	21 d	28 d	29 d
10	0	46	43	48	49	46

Applicant's summary and conclusion

Validity criteria fulfilled:

yes

Interpretation of results:

under test conditions no biodegradation observed

Conclusions:

The substance is considered to be not readily biodegradable according to EC Guideline C.4-B and classified accordingly.