The effects of pesticide mixtures and electric and magnetic fields on honeybees were evaluated in three experimental sites located in northern Italy: a control site far from anthropogenic-stress sources, a semi-natural site close to a high-voltage electric line and an agricultural site with intensive pesticide use. From each experimental site, young workers and foraging bees were taken monthly from May to October and analyzed for four enzymatic biomarkers: acetylcholinesterase (AChE), catalase (CAT), glutathione S-transferase (GST) and alkaline phosphatase (ALP). The results revealed time- and site-specific effects in respect to control site, confirming the role of biomarkers as diagnostic and early-warning tools for multi-stress sources on honeybees. In the electromagnetic-stress site, the effect of an over-activation of all analyzed biomarkers was observed at the end of the season. According to other literature findings, this event was related to a behavioral over-activation in a period in which bees should prepare themselves for overwintering. This finding poses potential problems for winter survival. In the pesticide-stress site, different pesticide-induced responses were identified. We demonstrated in the field that pesticide mixtures currently used in agriculture could greatly affect the biochemical parameters of bees (with both enzymatic under- and over-activations). Bees are subject to many stress factors. Here, the effects of electromagnetic fields and those of pesticides were evaluated by means of a battery of enzymatic biomarkers. In the electromagnetic-stress site, an effect of an over-activation of all analyzed biomarkers was observed at the end of the season, posing potential problems to winter survival. In the pesticide-stress site, pesticide mixtures, currently used in agriculture, were able to greatly affect biochemical parameters of bees (with both enzymatic under- and over-activations).

中文翻译：

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杀虫剂和电磁场对蜜蜂的影响：使用生物标志物的实地研究

在意大利北部的三个实验地点评估了农药混合物和电场和磁场对蜜蜂的影响：远离人为压力源的控制地点、靠近高压电线的半自然地点和农业地点大量使用农药。从每个实验地点，从 5 月到 10 月每月对年轻工人和觅食蜜蜂进行分析，分析四种酶生物标志物：乙酰胆碱酯酶 (AChE)、过氧化氢酶 (CAT)、谷胱甘肽 S-转移酶 (GST) 和碱性磷酸酶 (ALP)。结果揭示了控制部位的时间和部位特异性影响，证实了生物标志物作为蜜蜂多压力源的诊断和早期预警工具的作用。在电磁应力现场，在赛季结束时观察到所有分析的生物标志物过度激活的影响。根据其他文献发现，这一事件与蜜蜂应该为越冬做准备的时期的行为过度激活有关。这一发现给冬季生存带来了潜在的问题。在农药应激部位，确定了不同的农药诱导反应。我们在现场证明，目前农业中使用的农药混合物会极大地影响蜜​​蜂的生化参数（酶促激活不足和激活过度）。蜜蜂受到许多压力因素的影响。在这里，电磁场和农药的影响是通过一系列酶促生物标志物来评估的。在电磁应力现场，在季节结束时观察到所有分析的生物标志物过度激活的影响，对冬季生存构成潜在问题。在农药应激站点，目前用于农业的农药混合物能够极大地影响蜜​​蜂的生化参数（酶促激活不足和激活过度）。