Gas chromatography coupled to ICP-MS/MS for quantification of organophosphate pesticides in honey bee products after miniaturized QuEChERS extraction

Poster-Vendor
Poster Presentation

Prepared by J. Nelson1, J. Landero2, D. Munoz3, J. Stevens1
1 - Agilent, 5301 Stevens Creek Blvd, Santa Clara, CA, 95051, United States
2 - University of Cincinnati, , Cincinnati, OH, 45221, United States
3 - Autonomous University of Yucatan, , Merida, Yucatan, Mexico


Contact Information: jenny_nelson@agilent.com; 510-517-6475


ABSTRACT

The use of an elemental detector as powerful as inductively coupled plasma mass spectrometry (ICP-MS) has impacted several areas of research by increasing detection power and decreasing interferences. The powerful ionization source allows compound independent quantification of most metals and metalloids at sub-ppb levels. However, some biologically and environmentally relevant elements like S, P and Se suffer from intense isobaric interferences from atmospheric and plasma related sources, compromising ICP-MS measurements at low concentrations. In recent years a technological breakthrough on elemental analysis was introduced with a triple quadrupole configuration ICP-MS (ICP-QQQ), which dramatically increases the capabilities of this analytical technique to quantify difficult elements by removing the interferences using very controlled chemical reactions in the collision/reaction cell. We use this state of the art new instrumentation to measure organophosphate pesticides in honey bee products with very good results. For this, a gas chromatograph (GC) was directly coupled to an Agilent 8800 triple quadrupole ICP-MS in MS/MS mode, to monitor the hetero atom phosphorous as internal elemental tag in organophosphate pesticides. A miniaturized QuEChERS extraction and clean up procedure was optimized for bee wax, propolis, comb and pollen for GC-ICP-MS/MS analysis, and the results show recoveries of 75-105% for eighteen commonly used pesticides. The specific detection of phosphorous improved the quality of the obtained chromatograms for some of the most challenging samples, with limits of detection of 10 to 50 ng g-1. Real samples from different geographic origins were analyzed, and coumaphos was detected in three of them. This new approach can reduce the amount of toxic waste generated, by avoiding the stock of large amount of standards and its health hazard risks associated.