@article{fdi:010086380,
  title = {{P}ersistence of {N}-oxides transformation products of tertiary amine drugs at lab and field studies},
  author = {{M}anasfi, {R}. and {T}adic, {D}. and {G}omez, {O}. and {P}erez, {S}. and {C}hiron, {S}erge},
  editor = {},
  language = {{ENG}},
  abstract = {{T}his work aimed at studying the formation and persistence of {N}-oxides transformation products ({TP}s) of tertiary amine drugs by combining laboratory and field studies relevant for surface water. {A} monitoring study using passive samplers was first achieved for assessing attenuation of selected pharmaceuticals and their related {N} -oxides and {N}-, {O}-dealkylated {TP}s (i.e., venlafaxine, tramadol, amisulpride and sulpiride) along a 1.7 km river stretch between two sampling sites. {T}his study revealed the stability of tramadol-{N}-oxide, amisulpride-{N}-oxide and the fast dissipation of {O}-desmethylvenlafaxine-{N}-oxide, as well as the significance of {N}-oxidized {TP}s in comparison to {N}-dealkylated {TP}s and parent compounds in river. {L}ab-scale experiments were then implemented for a better understanding of their mechanisms of formation and degradation under aerobic water/sediment testing and under simulated solar photochemistry. {N}-oxidation reactions were always a minor transformation pathway under both degradation conditions with respect to {N}-and {O}-dealkylation reactions. {T}he amount of generated {N}-oxides were similar for venlafaxine, tramadol and sulpiride and peaked in the 8.4-12.8% and <4% of their initial concentration (100 mu g/{L}), during photodegradation and biodegradation experiments, respectively. {O}ther transformation pathways such as hydroxylation and alpha-{C}-hydroxylation followed by oxidation to amide or dehydration were also identified. {I}nvestigated {N}-oxides {TP}s (except {O}-desmethylvenlafaxine-{N}-oxide) were found stable under solar photolysis and aerobic biodegradation with a very slight reverse reaction to parent compound observed for tramadol-{N}-oxide and amisulpride-{N}-oxide. {L}ab-scale degradation experiments were not able to anticipate the high occurrence levels of {N}-oxide compounds in the environment. {T}his was most likely due to faster degradation kinetics and/or higher sorption to sediment of parent compounds and dealkylated {TP}s over {N}-oxide {TP}s, resulting in higher relative accumulation of the latter.},
  keywords = {{N}-oxides ; {T}ertiary amine ; {P}hototransformation ; {B}iotransformation ; {F}ield study ; {FRANCE} ; {MONTPELLIER}},
  booktitle = {},
  journal = {{C}hemosphere},
  volume = {309},
  numero = {1},
  pages = {136661 [8 p.]},
  ISSN = {0045-6535},
  year = {2022},
  DOI = {10.1016/j.chemosphere.2022.136661},
  URL = {https://www.documentation.ird.fr/hor/fdi:010086380},
}