The aerobic biotransformation of [test material] was studied in pond or river water/sediment system (water pH --, dissolved organic carbon -- %; sediment texture --, pH --, organic carbon -- %) from [country name] for – d in dark at -- ΊC.  [test material] was applied at the rate of – mg a.i./L.  The sediment/water ratio used was --.  The experiment was conducted in accordance with the – (the Guidelines followed), and in compliance with the – GLP standards (specify the GLP standards followed, e.g., OECD-GLP).  The test system consisted of – (e.g. Erlenmeyer flasks) attached/not attached with traps for the collection of CO2 and organic volatile compounds.  Samples were analyzed at 0, x1,  x2, -- and Xn days of incubation.  The water samples were extracted with – (solvent and/or method used; indicate, if not extracted), and the sediment samples were extracted with – (solvent and/or method used).  [Test material] residues were analysed by [TLC/HPLC – (detector)/GC-(detector)].   Identification of the transformation products was done by – (e.g.:  GC-MS, co-chromatography etc.).

 

The mean total recovery of radiolabelled material was – and -- % mean (mean ± std) of the applied in water and sediment, respectively.  The concentration of [parent] in water decreased from -- % at day 0, to -- % of the applied at study termination.  The concentration of [parent] in the sediment increased from -- % at day 0 to --% of the applied, at the end of the study period.  On – day/at test termination, -- % of the applied radioactivity was partitioned from water to sediment.

 

The major transformation products detected in water were – (Code and chemical nomenclature), with maximum concentrations of – and -- % of the applied amount, observed on the –th and –th day of incubation, respectively.  The corresponding concentrations in water at the end of the study period were – and -- % of the applied amount, respectively.  The major transformation products detected in sediment were (Code and chemical nomenclature), with maximum concentrations of – and –-% of the applied amount, observed on the –th and –th day of incubation, respectively.  The corresponding concentrations in sediment at the end of the study period were – and -- % of the applied amount, respectively.  (Specify if no major transformation products were detected).  The minor transformation products in water were – and – formed at a maximum of – to -- % of the applied amount.  The minor transformation products in sediment were – and – formed at a maximum of – to -- % of the applied amount.  The unidentified 14C during the study was -- % (range) of the applied amount.

 

Extractable [14C]residues in sediment decreased from -- % at day 0, to -- % of the applied amount at the end of incubation period.  Non-extractable [14C] residues in sediment increased from -- % at day 0, to -- % of the applied amount, at study termination.  At the end of the study, -- % and --% of the recovered radioactivity was present as CO2 and organic volatile compounds, respectively.  [If sterile treatments are used, compare the transformation in sterile and non-sterile treatments].

 

The half-life (lives)/50% decline times (DT50) of [test material] in aerobic water, sediment and in the entire system was/were --, --, and – days, respectively.

 

Describe the pathway of aerobic biotransformation of [test material] in water-sediment system.

 

[Briefly describe the results of the supplementary experiments, if any].