Generell metod för analys av pesticider med HS-SPME i kombination med GC-MS : Möjligheten att identifiera pesticider i känd lösning och i förgiftningsfall

Sammanfattning: This study focuses on a general method that has been developed for the identification of both polar- and nonpolar pesticidespolar pesticides in a known solution from EPA 8151 Herbicide acid mix by Merck including the ordered non-polar pesticide Prosulfocarb. The EPA-solution contains 16 analytes that has been completely identified when derivatized and spiked in acetone. The solution has also been spiked in blood samples, resulting in five calibration solutions in the range of 0,01 – 2,5 µg/g, followed by quantification. Identification of dinoseb and bentazone, spiked in blood, failed whereas the remaining 145 analytes were identified. The method uses headspace (HS) solid phase microextraction (SPME) in combination with gas chromatography (GC) with mass spectrometry (MS) in both scan and selected ion monitoring mode. A standard extraction- and derivatization procedure has been performed for the analysis of alcohols, phenols, and carboxylic acids with help from a protocol regarding the analysis of ethylene glycol in blood. Samples were introduced on the column with splitless injection where 1 µl were injected with an injector temperature of 250oC. Effective separations were achieved by using GS-GasPro PLOT-column (30 m x i.d. 320 µm x df 0 µm) in combination with a temperature programme that started at an initial temperature of 80oC (1 min) that increased by 10oC/min up to 280oC (1 min). The limit of detection (LOD) for the pesticides, spiked blood, were 0,01 – 2,5 µg/g where the lowest limit of 0,01 µg/g meant difficult identification whereas a greater identification was made at 0,05 µg/g. No identification was succeeded for the most polar substances in the forms of amines and amides in combination with carboxylic acid. Identification was however made for the less polar pesticides in the forms of alcohols, phenols, and carboxylic acids. The method must be further developed to identify the highly polar pesticides in different chemical classes. The current method can be used in occurring intoxications and in autopsy cases.