title: Evaluation of solid sorbents for the determination of fenhexamid, metalaxyl-M, pyrimethanil, malathion and myclobutanil residues in air samples: application to monitoring malathion and fenhexamid dissipation in greenhouse air using C-18 or Supelpak-2 for sampling.
abstract: A methodology is described for greenhouse air analysis by sampling fenhexamid, pyrimethanil, malathion, metalaxyl-M and myclobutanil in solid sorbents. Pesticides were determined by gas chromatography with NP Detector. The trapping efficiency of XAD-2, XAD-4, Supelpak-2, Florisil and C-18 at different sampling conditions (rate, time and air humidity) and pesticides concentration levels has been evaluated. No breakthrough was observed in the range of concentration studied (0.10-75 microg of each pesticide). In almost all the cases good stability results were obtained. Personal pumps have been used with selected sorbents (Supelpak-2 and C-18) in order to sample malathion and fenhexamid in air of experimental greenhouse after their application in a tomato crop. The dissipation process of the analytes in various time periods after application has been studied. Malathion concentrations varied between 20.1 microg m(-3) just after application and 1.06 microg m(-3) 3 days later. Fenhexamid concentrations, determined by high performance liquid chromatography with UV detection, fall rapidly; after 12 h post-application being below 0.50 microg m(-3).
authors.affiliation: Laboratory of Analytical Chemistry and Pesticides, Department of Agriculture, Crop Production and Rural Environment, University of Thessaly, Fytokou Str, Nea Ionia-Volos 38446, Greece. ntsirop@uth.gr
authors.forename: Nikolaos G
authors.initials: NG
authors.lastname: Tsiropoulos
authors.forename: Evangelos B
authors.initials: EB
authors.lastname: Bakeas
authors.forename: Vasilios
authors.initials: V
authors.lastname: Raptis
authors.forename: Stavroula S
authors.initials: SS
authors.lastname: Batistatou