title: Top-priority fragment QSAR approach in predicting pesticide aquatic toxicity.
abstract: In the framework of pesticide risk assessment, a fragment-based QSAR approach is presented to correlate LC50-96 h acute toxicity to the rainbow trout (Oncorhynchus mykiss). While there are other fragment-based modeling routes, our approach exploits the possibility of prioritizing fragments' contributions to toxicity. On the assumption that one fragment might be mainly responsible for the molecular toxicity, we developed a three-stage modeling strategy to select the most important moieties and to establish their priorities at a molecular level. This strategy was tested on a heterogeneous dataset containing 282 pesticides, collected under the EU-funded project Demetra. Quantitative toxicity prediction yielded good results for the training set (R2TR = 0.85) and the test set (R2TS = 0.75). The advantages and limitations of the current priority strategy are examined.
authors.affiliation: IRFMN, Mario Negri Institute for Pharmacological Research, via Eritrea 62, 20157 Milano, Italy. casalegno@marionegri.it
authors.forename: Mose'
authors.initials: M
authors.lastname: Casalegno
authors.forename: Guido
authors.initials: G
authors.lastname: Sello
authors.forename: Emilio
authors.initials: E
authors.lastname: Benfenati
mesh_terms: D000818:Animals; D003198:Computer Simulation; D007928:Lethal Dose 50; D008956:Models, Chemical; D015394:Molecular Structure; D017686:Oncorhynchus mykiss; D010575:Pesticides / Q000633:toxicity*; D021281:Quantitative Structure-Activity Relationship; D018570:Risk Assessment; D014873:Water Pollutants / Q000633:toxicity*
chemical_list: D010575:Pesticides; D014873:Water Pollutants