This paper presents studies performed for the monitoring of imidacloprid, clothianidin and thiamethoxam residues applied as seed treatment in rapeseed (Brassica napus ssp. oleifera), maize (Zea mays) and sunflower crops (Helianthus annuus). The experiments were located in representative areas of the mentioned crops. Residue levels were determined in plant samples at different phenological development stages, including flowers, as well as in bees and hive products (pollen, honeycomb, honey) by liquid chromatography/tandem mass spectroscopy (LC-MS/MS). The analyses were performed in ISO 17025-accredited laboratories, referring to the limit of quantification (LOQ), characteristic of the method used to determine the residues. In 2019, the percentage of samples that contained residues of the three substances, applied to the seed, was 16.39%, representing 20 samples out of the total of 122 analyzed samples. In 2020, 10 samples contained neonicotinoid residues above the LOQ, including 5 soil samples and 5 plant samples, representing 6.17% of the total samples. In 2021, from 149 samples with neonicotinoid applied as seed treatment, residues were identified in 12 soil samples and 11 plant samples, representing 15.43% of the total number of samples. In 2022, only 12 soil samples and 1 pasture sample contained residues above the LOQ. The results show that the highest percentage of samples with residues above the LOQ was recorded by the soil samples, while the flower and bee samples had the lowest percentages of samples with residues above the LOQ; no residues of the three neonicotinoid substances were identified in the honey samples.

Over the past years, increasing attention has been drawn to the adverse effects of agricultural pesticide use on pollinators, with honeybees being especially vulnerable. The aim of this study was to evaluate the levels of residues detectable and/or quantifiable of neonicotinoid pesticides and other pesticides in biological materials (bees, bee brood, etc.) and beehive products (honey, pollen, etc.) applied as seed dressings in rapeseed and sunflower plants in two growing seasons (2020–2021) in fields located in three agro-climatic regions in Romania. The study involved the comparative sampling of hive products (honey, pollen, adult bees, and brood) from experimental and control apiaries, followed by pesticide residue analysis in an accredited laboratory (Primoris) using validated chromatographic techniques (LC-MS/MS and GC-MS). Toxicological analyses of 96 samples, including bees, bee brood, honey, and pollen, confirmed the presence of residues in 46 samples, including 10 bee samples, 10 bee brood samples, 18 honey samples, and 8 pollen bread samples. The mean pesticide residue concentrations detected in hive products were 0.032 mg/kg in honey, 0.061 mg/kg in pollen, 0.167 mg/kg in bees, and 0.371 mg/kg in bee brood. The results highlight the exposure of honeybee colonies to multiple sources of pesticide residue contamination, under conditions where legal recommendations for the controlled application of agricultural treatments are not followed. The study provides relevant evidence for strengthening the risk assessment framework and underscores the need for adopting stricter monitoring and regulatory measures to ensure the protection of honeybee colony health.

So far, external parasites of Apis mellifera (A. externus, A. dorsalis, A. vagans) bees have been identified in many countries in Europe, but the level of infestation was not considered dangerous. In Romania cases of infestation with the three mentioned species were not identified in Apis mellifera, but their presence has been reported in some neighbor countries. The purpose of this paper is to report a possible infestation with A. externus and A. dorsalis or A. vagans in Romania. The study was conducted on a total of 35 apiaries within 4 counties in Southern Romania, on samples of bees, drones and portions of honeycomb with/without brood. A single case of infestation was incidentally identified by microscopic investigation on samples of drone brood combs. Morphological aspects of the parasite investigated microscopically suspects the presence of an external mite with characteristics of Acarapis species. The results of our investigations show that infestation with Acarapis (A. externus and A. dorsalis or A.vagans) does not constitute a threat to the Apis mellifera Carpathica, but draws attention to their presence in the apiary in thesouth of the country.

Twenty-one clinically healthy honeybee colonies were monitored in a private apiary located in Vâlcea County, Romania, within an area influenced by electromagnetic fields (EMF) according to the National Authority for Management and Regulation in Communications (ANCOM) allocations. The site was situated below the activation threshold of the 5G n78 band (3.3–3.8 GHz), where mean field intensities of 12.74 mW/m² and peak values of 17.96 mW/m² were recorded. For each colony, five thermographic measurements were conducted (at the hive entrance, left lateral wall, rear wall, right lateral wall, and interior), totaling 105 recordings. During the inactive beekeeping season of 2025, strong colonies initiated winter clustering at approximately 7 °C, medium-strength colonies at 8 °C, and swarms at 10 °C, values consistent with the literature (7–10 °C). Thermographic analyses showed that only strong colonies consistently maintained the optimal internal range (32–36 °C), although peripheral zones exhibited peaks up to 52 °C. Medium-strength colonies displayed higher variability, with maxima of 52–55 °C, while swarms remained unstable, fluctuating around the minimum optimal temperature (≈25 °C) and frequently dropping to lower values (21–24 °C), confirming significant differences in thermoregulatory capacity among colony categories. Acoustic monitoring of the colonies revealed a nonlinear profile of sound level: ~36 dB at 50 m, maximum levels of 43–45 dB at 400–540 m due to reflections and interferences of EMF, and ~40 dB at 640–1000 m, with high variability influenced by terrain and nearby constructions.