Determination of Eight Herbicides in Fishery Water by Gas Chromatography-Mass Spectrometry

Abstract:

To measure herbicides residues in fishery water, gas chromatography-mass spectrometry was developed to determine trifluralin, pendimethalin, alachlor, acetochlor, butachlor, simazine, atrazine, and prometryn. The samples were adjusted to salinity 20−30 with NaCl, extracted by dichloromethane, and cleaned up with Florisil solid phase extraction (SPE) column. The analytes were detected by gas chromatography-mass spectrometry under the selected reaction monitoring mode and quantified by external standard method. The peak area was linear to the concentration of eight herbicides residues (0.010−1.000 µg/L), and the correlation coefficients (R2) were all more than 0.990. According to S/N≥3, the detection limit of rifluralin, simazine, atrazine, acetochlor, alachlor, prometryn, pendimethalin, and butachlo were 0.022, 0.031, 0.028, 0.038, 0.041, 0.035, 0.025, and 0.020 μg/L, respectivly. The limit of quantification was 0.05 μg/L for all eight herbicides based on the actual samples spiked recoveries between 70% and 120%, S/N≥10, and the relative standard deviation≤15%. The average recovery of the eight herbicides fortified in different negative samples at 0.05, 0.5, and 2.0 µg/L were in the range of 74.7%−97.7%, and the relative standard deviations were less than 12.00%. These results indicated that the method has the advantage of simplicity, sensitivity and repeatability, which could provide technical support for the detection of these eight herbicides residues in fishery water.