Persistence assessment of cyclohexyl- and norbornyl-derived ketones and their degradation products in different OECD screening tests

•Persistence of synthetic cyclohexyl- and norbornyl-derived ketones was assessed.•Test results for cyclohexyl-derived ketones approached ultimate biodegradation.•Norbornyl-derived ketones yielded primarily 2-bicyclo[2.2.1]heptane carboxylic acid.•Re-synthesized degradation products were biodegradable with fresh inocula.•Results underline OECD screening test limitations and need for reduced stringency. The persistence of synthetic cyclohexyl- and norbornyl-derived ketones was assessed by using OECD 301F and 301D biodegradation tests. While cyclohexyl-derived ketones either reached or came close to the pass level (60%) after 60d, the corresponding norbornyl derivatives yielded significantly less biodegradation (