Overview
Durkalec and colleagues measured 18 trace elements, including lead, cadmium, arsenic and mercury, in pollen stored by honey bees, bumble bees and red mason bees at 128 sites in apple orchards and oilseed rape fields across eight European countries. The goal was to estimate dietary risk to the bees, which was low. Red mason bee pollen stores carried much more of most elements than honey bee or bumble bee stores, probably because of mud in their nests.
Key numbers
- Honey bee stored pollen medians: aluminum 14.6, arsenic 0.009, lead 0.047 and vanadium 0.034 µg g-1 wet weight (Section 3.1, p. 6).
- Red mason bee stored pollen medians: arsenic 0.398 and lead 0.656 µg g-1 wet weight (Section 3.1).
- Copper in honey bee stored pollen: median 8.08 (apple orchards) vs 7.02 µg g-1 ww (oilseed rape) (Section 3.1).
Methods (brief)
About 200 mg of homogenized stored pollen was digested by microwave in nitric acid and hydrogen peroxide and read by ICP-MS; mercury was measured by direct combustion with gold amalgamation. Methods are ISO/IEC 17025 accredited, with reference materials and proficiency testing. Results below LOQ were handled by Kaplan-Meier substitution.
Evidence Fitness
A large, well-controlled pan-European dataset, but the main text prints only a few medians; most element statistics, including cadmium and mercury, are in figures and supplementary tables that were not available. For bee-pollen this is a proxy: it measures pollen stored inside hives and nests (beebread) for bee exposure, not retail bee pollen, so that page is not linked. The bumble bee and mason bee stores are not human foods.