Registration Dossier

Environmental fate & pathways

Additional information on environmental fate and behaviour

Administrative data

Endpoint:
additional information on environmental fate and behaviour
Type of information:
experimental study
Adequacy of study:
supporting study
Reliability:
2 (reliable with restrictions)
Rationale for reliability incl. deficiencies:
other: Published in peer reviewed literature, minor restrictions in design and/or reporting but otherwise adequate for assessment

Data source

Reference
Reference Type:
publication
Title:
Effects of sorption on the biodegradation of 2-methylpyridine in aqueous suspensions of reference clay minerals
Author:
O'Loughlin et al
Year:
2000
Bibliographic source:
Environmental Toxicology and Chemistry, Vol. 19, No. 9, pp. 2168–2174, 2000

Materials and methods

Test guideline
Qualifier:
no guideline followed
Principles of method if other than guideline:
"The effects of sorption on the bioavailability of the test substance were investigated by determining the biodegradation of the test substance by an Arthrobacter sp. in aqueous suspensions of reference clay minerals and a synthetic cation exchange resin. Adsorption the test substance on kaolinite, illite, hectorite, montmorillonite, and Dowex was determined by the batch equilibrium method." (O'Loughlin et al., 2000)
GLP compliance:
not specified
Type of study / information:
Effects of sorption on the biodegradation of 2-methylpyridine in aqueous suspensions of reference clay minerals

Test material

Constituent 1
Chemical structure
Reference substance name:
2-methylpyridine
EC Number:
203-643-7
EC Name:
2-methylpyridine
Cas Number:
109-06-8
Molecular formula:
C6H7N
IUPAC Name:
2-methylpyridine
Details on test material:
- Name of test material (as cited in study report): 2-methylpyridine

Results and discussion

Any other information on results incl. tables

O'Loughlin et al., 2000 conclude that:

"In general, adsorption of 2-MP was positively correlated with the cation exchange capacity of the sorbent, suggesting that sorption of 2-MP on clay minerals occurs through a cation exchange reaction via the 2-methylpyridinium ion. The biodegradation of 2-MP was most rapid in the kaolinite suspensions, followed by no clay > illite >> Dowex > hectorite/montmorillonite. With the exception of kaolinite, adsorption of 2-MP on clay minerals and Dowex reduced the rate of biodegradation. The degree of attenuation was positively correlated with the fraction of 2-MP sorbed, suggesting that sorbed 2-MP was not directly available for degradation. Desorption was not rate limiting in suspensions containing hectorite, montmorillonite, or Dowex; however, desorption may have become limiting in the kaolinite and illite suspensions. The results of this study clearly indicate that adsorption can directly affect the degradation of 2-MP in complex mineral systems."

Applicant's summary and conclusion