The use of honey as environmental biomonitor of pesticides contamination in northern Lebanon

The intensive use of pesticides in agriculture generates a contamination of the environment that must be assessed. Bee products such as honey, widely consumed, are not spared by this considerable contamination that can lead to health risks. Bees and their products (honey, nectar, pollen, etc) are considered as real indicators of environmental health. Indeed, these insects, characterized by a specified body and a high mobility, are considered particularly suitable to keep, with high sensitivity, pesticides with which they come in contact. So the analysis of these insects or of their products as honey has been demonstrated as a good bio indicator of environmental quality. In this study, 18 samples of honey collected from North Lebanon, were assayed for their contamination by 84 pesticides. Multi residue extraction was based on QuEChERS, followed by chromatographic analysis by LC–MS/MS and GC–MS/MS. For gas chromatographic analysis, samples were concentrated by SPME before being injected to the GC column. At first, the method was developed and validated using organic honey, and then the collected samples were analyzed. The limits of detection and quantification as well as the repeatability and the reproducibility of the method have been defined: between 0.1 and 25.2 ng g−1 and between 0.6 to 83.1 ng g−1 for the limits detection and quantification respectively. Furthermore, the repeatability was between 0.2 and 15% and the reproducibility between 0.2 and 18%. Concerning the analyzed samples, residues of many pesticides have been found in each sample. Samples collected from the plain of Akkar and the Byblos area, widely known for their agricultural productions, were the most contaminated by pesticides. In fact, pesticide levels found in honey collected from Akkar and Byblos were 1753.92 and 695.13 ng g−1 respectively. Contrariwise, samples collected from the Cedars of Lebanon had the lowest pesticides concentration with a total concentration of 19.5 ng g−1. In conclusion, this study shows that honey can indicate the specific pollution of a given environment and can be considered as an appropriated sentinel for environmental biomonitoring. © 2017, Springer International Publishing AG.