For the requirements of a metabolism study on a carbon-14 labelled plant protection product (PPP) test item, consideration should be made on the label position (OECD Guidelines for the Testing of Chemicals), specifications and stability. Using [<sup>14</sup>C]diflufenican as an example, the factors taken into account when producing the test item for one of more studies over a period of time can be demonstrated. The molecule has three different rings each of which require a <sup>14</sup>C-label. Each label is manufactured by a separate route and the effect of the label position, specific activity and storage conditions on stability will be discussed.  Furthermore, the different studies using radiolabelled compounds, such as metabolism studies in livestock and plants and environmental fate&lt;span style="font-size:10.8333px"&gt; have a&lt;/span&gt;dditional requirements for the carbon-14 labelled compound. The purpose of those studies is to investigate the degradation pathway of a test item like diflufenican. Therefore, metabolites and degradation products observed in the course of a study have to be analysed and identified. Especially, for analysis and identification by high resolution mass spectrometry experiments, the labelling position and degree is important. Consequently, the discussion will also include aspects and requirements from the point of view of the application of radiolabelled compounds.

Environmental metabolism studies with carbon-14 labelled plant protection products

256th National Meeting (2018)

The official archive and repository for all ACS Meetings & Expositions abstracts and select posters or presentations.