Carbendazim

Biodegradation in water: screening tests

Administrative data

Endpoint:

biodegradation in water: ready biodegradability

Type of information:

experimental study

Adequacy of study:

key study

Study period:

1984

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

data from handbook or collection of data

Data source

Reference

Reference Type:

publication

Title:

Unnamed

Year:

2009

Report date:

2009

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

OECD Guideline 302 B (Inherent biodegradability: Zahn-Wellens/EMPA Test)

GLP compliance:

no

Test material

Test material information

Constituent 1

Reference substance name:

Carbendazim

EC Number:

234-232-0

EC Name:

Carbendazim

Cas Number:

10605-21-7

Molecular formula:

C9H9N3O2

IUPAC Name:

carbendazim

Study design

Inoculum or test system:

activated sludge (adaptation not specified)

Duration of test (contact time):

28 d

Initial test substance concentration

Initial conc.:

27 mg/L

Based on:

DOC

Details on study design:

The substance was carried out for 28 days at 20°C. The biodegradation process of 27 mg/l carbendazim was monitored by determination of dissolved organic carbon (DOC) and the chemical oxygen (COD) during test period.

Results and discussion

% Degradation

Parameter:

% degradation (O2 consumption)

Value:

< 10

Sampling time:

21 d

Details on results:

After 21 days the amount of oxygen uptake by microbial polulation was less than 10%. Adsorption processes did play a role because 95% of substance was eliminable after 3 h from the water phase. This effect is due to adsorption to the sludge and is not due to real biodegradation, which would last longer than adsorption.
Carbendazim is not considered to have had an inhibitory effect o sewage bacteria under the conditions of this test. The active substance carbendazim can catagorized as not inherent biodegradable in the static test after 28 days.

Applicant's summary and conclusion

Validity criteria fulfilled:

not applicable

Remarks:

A validation of procedure was not possible vecause there were no information about degradation of a reference compound and source and concentration of inoculum.

Interpretation of results:

not inherently biodegradable

Conclusions:

A validation of test procedure is not possible, but results are plausible. Carbendazim is not considered to have had an inhibitory effect o sewage bacteria under the conditions of this test. The active substance carbendazim can catagorized as not inherent biodegradable in the static test after 28 days.