Determination of Azole Fungicides in Atmospheric Samples Collected in the Canadian Prairies by LC/MS/MS

Abstract

Abstract An LC/MS/MS method has been developed for the determination of azole fungicides in the atmosphere at low pg/m3 concentrations. Detection limits in the range of 0.16 to 1.2 pg/m3 for a weekly air sample were obtained for the 31 fungicides analyzed. This work represents the first detection of propiconazole, prothioconazole-desthio, and trace levels of hexaconazole in gas phase atmospheric samples collected in a Canadian agricultural region. Samples were collected during April–October 2010 at Bratt's Lake, Saskatchewan, in the Canadian prairies where there was known historical use of selected azole fungicides. Atmospheric concentrations were above detection limits only during June–August 2010, with maximum concentrations occurring in July at 77.9 and 37.5 pg/m3 for propiconazole and prothioconazole-desthio, respectively. Gas phase atmospheric concentrations of propiconazole and prothioconazole-desthio increased following a spring and early summer with higher than normal daily precipitation. These azole fungicides showed the largest gas phase concentrations during periods of lower temperature and during sampling events with at least 1 day with no precipitation. The higher atmospheric gas phase concentrations of each azole fungicide were observed on different days, indicating different formulations may be in use in the prairie agricultural region.