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  • Author: Andrzej Posyniak x
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Open access

Anna Gajda, Andrzej Posyniak, Andrzej Bober, Tomasz Błądek and Jan Żmudzki

Summary

A liquid chromatography method with UV detection for determination of oxytetracycline (OTC) in honey has been developed. The samples were extracted with the solution of oxalic acid. The clean-up procedure was performed by solid phase extraction (SPE) using polymeric Strata X and carboxylic acid cartridges. Chromatographic separation was carried out on the Luna C8 analytical column with mobile phase consisting of acetonitrile-0.02 M oxalic acid. The method has been successfully validated according to the requirements of the European Decision 2002/657/EC and this method is used in routine control of oxytetracycline in honey samples. The limit of detection (LOD) and limit of quantification (LOQ) of the presented method were 10 and 12.5 μg/kg, respectively. The developed method has also been verified in quantitative determination of oxytetracycline residues in honey after experimental treatment with this product in bee colonies.

Open access

Tomasz Kiljanek, Alicja Niewiadowska and Andrzej Posyniak

Abstract

During the 2000s, the problem of pesticide poisoning of honeybees seemed to be almost solved. The number of cases has decreased in comparison to the 1970s. The problem of acute honeybee poisoning, however, has not disappeared, but instead has transformed into a problem of poisoning from ‘traditional’ pesticides like organophosphorus pesticides or pyrethroids, to poisoning from additional sources of ‘modern’ systemic neonicotinoids and fipronil. In this article, the biological activity of pesticides was reviewed. The poisoning symptoms, incident definitions, and monitoring systems, as well as the interpretation of the analytical results, were also reviewed. The range of pesticides, and the detected concentrations of pesticides in poisoned honeybee samples, were reviewed. And, for the first time, cases of poisoning related to neonicotinoids were reviewed. The latter especially is of practical importance and could be helpful to analysts and investigators of honeybee poisoning incidents. It is assumed that secondary poisoning induced by plant collected materials contaminated with systemic pesticides occurs. Food stored in a hive and contaminated with systemic pesticides consumed continuously by the same generation of winter bees, may result in sub-lethal intoxication. This leads to abnormal behaviour identified during acute intoxication. The final result is that the bees discontinue their social role in the honeybee colony super organism, and colony collapse disorder (CCD) takes place. The process described above refers primarily to robust and strong colonies that were able to collect plenty of food due to effective plant protection.