Contamination of Honeybee (Apis mellifera L.) Royal Jelly by Pesticides and Sample Preparation Methods for Its Determination: A Critical Appraisal

Pesticides can easily enter the food chain, harming bee populations and ecosystems. Exposure of beehive products to various contaminants has been identified as one of the factors contributing to the decline in bee populations, and multiple food alerts have been reported. Despite this fact, royal jelly, a valuable bee product with nutritional and functional properties, has received less attention in this context. Pesticide residues of different chemical class can contaminate royal jelly when foraging bees collect pollen or nectar from pesticide-treated flowers, or in some cases, due to its frequent and inappropriate use in the treatment of mites in beehives. To monitor this issue and also make it more reliable, it is crucial to develop effective sample preparation methods for extracting pesticides from royal jelly for subsequent analysis. In this context, this review provides information about sample preparation methods (solid-phase extraction, solvent extraction, and QuEChERS-quick, easy, cheap, effective, rugged and safe) and analytical methods that have been validated or improved to extract and analyze pesticides, respectively, in royal jelly samples of different origins. Finally, future perspectives are discussed. With this background, we aim to provide data that can guide future research related to this topic.

Determination of acaricides in honeys from different botanical origins by gas chromatography-mass spectrometry

An analytical method has been proposed and validated to determine seven acaricides (atrazine, chlorpyrifos, chlorfenvinphos, α-endosulfan, bromopropylate, coumaphos, and τ-fluvalinate) in honeys from different botanical origins (multifloral, heather and rosemary) by means of gas chromatography-mass spectrometry. An efficient and simple sample treatment was proposed that involved a solvent extraction with an ethyl acetate and cyclohexane (50:50, v/v) mixture. Chromatographic analysis (<25 min) was performed in a DB-5MS column under programmed temperature conditions. The method was validated in terms of selectivity, limits of detection (0.2-2.0 µg kg^-1) and quantification (0.5-7.6 µg kg^-1), linearity (limit of quantification-700 (heather) or 800 (multifloral and rosemary) µg kg^-1), matrix effect (<20 % in most cases), trueness (recoveries between 81 % and 108 %), and precision (relative standard deviation < 15 %). Finally, of the seven acaricides investigated in several honey samples only τ-fluvalinate residues (<limit of quantification - 23 µg kg^-1) were found.

Halogenated Volatile Organic Compounds in Water Samples and Inorganic Elements Levels in Ores for Characterizing a High Anthropogenic Polluted Area in the Northern Latium Region (Italy)

This paper shows a characterization of the organic and inorganic fraction of river waters (Tiber and Marta) and ores/soil samples collected in the Northern Latium region of Italy for evaluating the anthropogenic/natural source contribution to the environmental pollution of this area. For organic compounds, organochloride volatile compounds in Tiber and Marta rivers were analyzed by two different clean-up methods (i.e., liquid–liquid extraction and static headspace) followed by gas chromatography–electron capture detector (GC-ECD) analysis. The results show very high concentrations of bromoform (up to 1.82 and 3.2 µg L⁻¹ in Tiber and Marta rivers, respectively), due to the presence of greenhouse crops, and of chloroform and tetrachloroethene, due to the presence of handicrafts installations. For the qualitative and quantitative assessment of the inorganic fraction, it is highlighted the use of a nuclear analytical method, instrumental neutron activation analysis, which allows having more information as possible from the sample without performing any chemical-physical pretreatment. The results have evidenced high levels of mercury (mean value 88.6 µg g⁻¹), antimony (77.7 µg g⁻¹), strontium (12,039 µg g⁻¹) and zinc (103 µg g⁻¹), whereas rare earth elements show levels similar to the literature data. Particular consideration is drawn for arsenic (414 µg g⁻¹): the levels found in this paper (ranging between 1 and 5100 µg g⁻¹) explain the high content of such element (as arsenates) in the aquifer, a big issue in this area.

Analytical Scheme for Simultaneous Determination of Phthalates and Bisphenol A in Honey Samples Based on Dispersive Liquid-Liquid Microextraction Followed by GC-IT/MS. Effect of the Thermal Stress on PAE/BP-A Levels

In this paper, an analytical protocol was developed for the simultaneous determination of phthalates (di-methyl phthalate DMP, di-ethyl phthalate DEP, di-isobutyl phthalate DiBP, di-n-butyl phthalate DBP, bis-(2-ethylhexyl) phthalate DEHP, di-n-octyl phthalate DNOP) and bisphenol A (BPA). The extraction technique used was the ultrasound vortex assisted dispersive liquid–liquid microextraction (UVA-DLLME). The method involves analyte extraction using 75 µL of benzene and subsequent analysis by gas chromatography combined with ion trap mass spectrometry (GC-IT/MS). The method is sensitive, reliable, and reproducible with a limit of detection (LOD) below 13 ng g⁻¹ and limit of quantification (LOQ) below 22 ng g⁻¹ and the intra- and inter-day errors below 7.2 and 9.3, respectively. The method developed and validated was applied to six honey samples (i.e., four single-use commercial ones and two home-made ones. Some phthalates were found in the samples at concentrations below the specific migration limits (SMLs). Furthermore, the commercial samples were subjected to two different thermal stresses (24 h and 48 h at 40 °C) for evidence of the release of plastic from the containers. An increase in the phthalate concentrations was observed, especially during the first phase of the shock, but the levels were still within the limits of the regulations.

Analytical Method Development and Chemometric Approach for Evidencing Presence of Plasticizer Residues in Nectar Honey Samples

Over the years, anthropogenic sources have increasingly affected food quality. One of the most sensitive and nutritional matrices affected by chemical contamination is honey, due to the use of acaricides. Recently, the attention has moved to the presence of phthalates (PAEs) and bisphenol A (BP-A), molecules present in plastic materials used both in the production phase and in the conservation of honey. In this study, an analytical method for the simultaneous determination of PAEs (dimethyl phthalate DMP, diethyl phthalate DEP, diisobutyl phthalate DiBP, dibutyl phthalate DBP, bis(2-ethylhexyl) phthalate DEHP, and di-n-octyl-phthalate DnOP) and BP-A was developed. The extraction technique is the ultrasound-vortex-assisted dispersive liquid-liquid microextraction (UVA-DLLME), using 150 µL of toluene as an extraction solvent, followed by the gas chromatography coupled with ion trap mass spectrometry analysis (GC-IT/MS). The developed method is sensitive, reliable, and reproducible: it shows high correlation coefficients (R > 0.999); limits of detection (LODs) less than 11 ng·g-1; limits of quantification (LOQs) less than 16 ng·g-1; repeatability below 3.6%, except BP-A (11.6%); and accuracy below 4.8%, except BP-A (17.6%). The method was applied to 47 nectar honey samples for evidencing similarities among them. The chemometric approach based on Hierarchical Cluster Analysis and Principal Component Analysis evidenced some similitudes about sample origin as well as marked differences between PAE and BP-A sources.

Determination of six organophosphorus pesticides in water samples by three-dimensional graphene aerogel-based solid-phase extraction combined with gas chromatography/mass spectrometry

In the present study, a three-dimensional graphene aerogel (3D-GA), synthesised by chemical reduction of an aqueous solution of graphene oxides (GOs) with ethylenediaminethermal by a simple water bath method followed by freeze-drying treatment, was used for the solid-phase extraction (SPE) of six organophosphorus pesticides (OPPs) (i.e. trichlorfon, dimethoate, ethoprophos, parathion, fenitrothion and fenthion) from water samples. The target analytes were extracted using packed SPE cartridges and then eluted with tetrahydrofuran. The eluate was collected and dried with high-purity nitrogen gas at room temperature. After redissolving in acetone, the residue was analysed using gas chromatography/mass spectrometry (GC/MS). The proposed method demonstrated a good linearity between 0.5 and 500 μg L⁻¹ with the correlation coefficient of 0.9990–0.9998. The limits of detection (LODs) (S/N = 3) and the limits of quantification (LOQs) (S/N = 10) for the six OPPs pesticides were in the range of 0.12–0.58 μg L⁻¹ and 0.41–1.96 μg L⁻¹, respectively. The accuracy of the present method was evaluated by measuring the recovery of the spiked samples, which ranged from 93.8% to 104.2% with relative standard deviations (RSDs) of 1.1–5.6%. The established method was successfully applied to the determination of the target analytes in environmental water samples including tap water, river water, drinking water and lake water, demonstrating its great potential for the determination of OPPs in water.

3D graphene aerogel fabricated via chemical reduction followed by freeze-drying treatment was used as SPE sorbent to extract OPPs from water sample.

Use of costic acid, a natural extract from Dittrichia viscosa, for the control of Varroa destructor, a parasite of the European honey bee

Costic acid has been isolated from the plant Dittrichia viscosa and its efficacy against Varroa destructor, a parasite of Apis mellifera, the European honey bee, has been studied. Costic acid exhibited potent in vivo acaricidal activity against the parasite. Initial experiments showed that the compound is not toxic for human umbilical vein endothelial cells (HUVEC) at concentrations of up to 230 micromolar (μM), indicating that costic acid could be used as a safe, low-cost and efficient agent for controlling varroosis in honey bee colonies.