Kast Christina, Kilchenmann Verena, Reinhard Hans, Droz Benoit, Lucchetti Matteo Angelo, Dübecke Arne, Beckh Gudrun, Zoller Otmar
a Agroscope , Swiss Bee Research Centre , Bern , Switzerland.
b Federal Food Safety and Veterinary Office (FSVO) , Risk Assessment Division , Bern , Switzerland.
Food Addit Contam Part A Chem Anal Control Expo Risk Assess. 2018 Feb;35(2):316-327. doi: 10.1080/19440049.2017.1378443. Epub 2017 Sep 28.
Various studies have shown that bee-collected pollen sold as nutritional supplements may contain toxic pyrrolizidine alkaloids (PAs) and, thus, pose a potential health risk for consumers. The level of contamination may vary according to its geographical and botanical origin. Here, the PA content of pollen produced in Switzerland was studied and 32 commercially available bee-collected pollen supplements produced between 2010 and 2014 were analysed. In addition, at what time period bees collect PA-containing pollen was investigated. Hence, this study looked into the occurrence of PAs in pollen samples collected daily during two-to-three consecutive seasons. Furthermore, the PA spectrum in pollen was compared to the spectrum found in flower heads of PA-plants to unambiguously identify plants responsible for PA contamination of pollen. The PA concentration of commercial and daily collected pollen was determined by target analysis using an HPLC-MS/MS system, allowing the detection of 18 different PAs and PA N-oxides found in the genera Echium, Eupatorium and Senecio, while the comparison of the PA spectrum in pollen and flower heads was performed by LC-HR-MS, allowing the detection of all PA types in a sample, including saturated, non-carcinogenic PAs. Of the commercially available pollen, 31% contained PAs with a mean concentration of 319 ng/g, mainly Echium- and Eupatorium-type PAs, while the PA concentrations were below the limit of quantitation (LOQ) in 69% of the pollen samples. Bees collected pollen containing Echium-type PAs mainly in June and July, while they gathered pollen containing Eupatorium-type PAs from mid-July to August. Senecio-type PAs appeared from June to September. Comparison of the PA array in pollen and plants identified E. vulgare and E. cannabinum as the main plants responsible for PA contamination of Swiss bee-collected pollen, and to a lesser extent also identified plants belonging to the genus Senecio.
多项研究表明，作为营养补充剂出售的蜂采花粉可能含有有毒的吡咯里西啶生物碱（PAs），因此对消费者构成潜在的健康风险。污染水平可能因其地理和植物来源而异。在此，对瑞士生产的花粉中的PA含量进行了研究，并分析了2010年至2014年间生产的32种市售蜂采花粉补充剂。此外，还调查了蜜蜂在什么时间段采集含PA的花粉。因此，本研究调查了在连续两到三个季节中每天采集的花粉样本中PA的出现情况。此外，还将花粉中的PA谱与PA植物花头中的谱进行了比较，以明确鉴定导致花粉PA污染的植物。通过使用HPLC-MS/MS系统进行目标分析来测定商业采集和每日采集花粉中的PA浓度，该系统能够检测到在蓝蓟属、泽兰属和千里光属中发现的18种不同的PA和PA N-氧化物，而通过LC-HR-MS对花粉和花头中的PA谱进行比较，能够检测样本中的所有PA类型，包括饱和的、非致癌的PA。在市售花粉中，31%含有PA，平均浓度为319 ng/g，主要是蓝蓟属和泽兰属类型的PA，而69%的花粉样本中PA浓度低于定量限（LOQ）。蜜蜂主要在6月和7月采集含蓝蓟属类型PA的花粉，而它们在7月中旬至8月采集含泽兰属类型PA的花粉。千里光属类型的PA在6月至9月出现。花粉和植物中PA阵列的比较确定了普通蓝蓟和大麻叶泽兰是瑞士蜂采花粉PA污染的主要植物，在较小程度上也确定了千里光属的植物。
