Search results for "Phenothrin"
showing 3 items of 3 documents
Determination of pyrethroid insecticide residues in vegetable oils by using combined solid-phases extraction and tandem mass spectrometry detection
2005
Abstract A methodology has been developed for the determination of pyrethroid insecticide residues in vegetable oils, based in a solid-phase extraction (SPE) with combined solid supports phases. Several solid phases such as florisil, alumina, C18 and graphitized carbon black were tested in order to minimize fat residues, being a combination of treated alumina and C18 which provided the best results. Oil samples were partitioned with acetonitrile–hexane (1:1) and then eluted through a combined column packed with deactivated basic-alumina and C18, employing the acetonitrile extract as elution solvent. Gas chromatography tandem mass spectrometry was used for determination. Tetramethrin, Bifent…
Microwave-assisted extraction of pyrethroid insecticides from semi permeable membrane devices (SPMDs) used to indoor air monitoring
2006
Abstract A rapid and environmentally friendly methodology was developed for the extraction of pyrethroid insecticides from semi permeable membrane devices (SPMDs), in which they were preconcentrated in gas phase. The method was based on gas chromatography mass–mass spectrometry determination after a microwave-assisted extraction, in front of the widely employed dialysis method. SPMDs were extracted twice with 30 mL hexane:acetone, irradiated with 250 W power output, until 90 °C in 10 min, this temperature being held for another 10 min. Clean-up of the extracts was performed by acetonitrile–hexane partitioning and solid-phase extraction (SPE) with a combined cartridge of 2 g basic-alumina, d…
Use of semipermeable membrane devices for monitoring pesticides in indoor air.
2009
Abstract In this work, 40 pesticides from different categories were analyzed in the air of 20 indoor places that have an intensive use of pesticides. Passive sampling was carried out by using semipermeable membrane devices (SPMDs) deployed for 7 days. SPMDs were analyzed using microwave-assisted extraction and GC/MS. PCB-195 was used as an internal standard. Recoveries ranged between 81 and 108 for many compounds, with RSD values <11. Typical LOD values for 7 days of sampling were from 0.1 to 3.1 ng/m. Propamocarb, propoxur, carbosulfan, pirimicarb, metribuzin, metalaxyl, pendimethalin, oxadiazon, phenothrin, and permethrin were detected in 11 sampling sites, with air concentrations …