Registration Dossier

Environmental fate & pathways

Biodegradation in water and sediment: simulation tests

Administrative data

Endpoint:
biodegradation in water and sediment: simulation tests
Type of information:
experimental study
Adequacy of study:
key study
Reliability:
2 (reliable with restrictions)
Rationale for reliability incl. deficiencies:
other: Basic data given, comparable to guidelines/standards.

Data source

Reference
Reference Type:
publication
Title:
Toxicity and Anaerobic Biodegradability of Pyridine and Its Derivatives Under Sulfidogenic Conditions.
Author:
Lui SM, Wu CH and Huang HJ
Year:
1989
Bibliographic source:
Chemosphere 10: 2345-2357

Materials and methods

Test guideline
Qualifier:
no guideline followed
Principles of method if other than guideline:
Assessment of degradation based on substrate depletion in sediment slurries.
GLP compliance:
not specified

Test material

Constituent 1
Chemical structure
Reference substance name:
Nicotinonitrile
EC Number:
202-863-0
EC Name:
Nicotinonitrile
Cas Number:
100-54-9
Molecular formula:
C6H4N2
IUPAC Name:
pyridine-3-carbonitrile
Constituent 2
Reference substance name:
3-Cyanolpyridine
IUPAC Name:
3-Cyanolpyridine
Details on test material:
Purchased from Tokyo Kasei (Tokyo, Japan). No further details

Study design

Oxygen conditions:
anaerobic
Remarks:
sulfate-reducing conditions
Inoculum or test system:
other: estuarine sediment and overlying site water
Details on source and properties of sediment:
The sediment (<1mm, sieved) and overlying water (pH 7.48, salinity 13%, sulfate concentration 13.5 mM) water were collected from the estuary of Tansui River (Guandu, Taipei).
Details on inoculum:
The sediment (<1mm, sieved) and overlying water (pH 7.48, salinity 13%, sulfate concentration 13.5 mM) water were collected from the estuary of Tansui River (Guandu, Taipei).
Duration of test (contact time):
200 d

Results and discussion

Half-life of parent compound / 50% disappearance time (DT50)
Compartment:
sediment
DT50:
1 d
Type:
(pseudo-)first order (= half-life)
Remarks on result:
other: Half-life is less than 1 day
Other kinetic parameters:
pseudo-first order rate constant

Any other information on results incl. tables

3 -Cyanopyridine was transformed into an intermediate product in 19 days, with a lag time of 4 days.

Applicant's summary and conclusion

Validity criteria
Validity criteria fulfilled:
not applicable
Remarks:
not a guideline study
Conclusions:
3-Cyanopyridine showed evidence of anaerobic degradation in sediment slurries, with a half-life of less than 1 day, and dull degradation within 19 days.