(A) Airborne PM (red) on the honey bees is mostly concentrated along the costal margin of the fore wings, the medial plane of the head, and the inner surface of the hind legs.

<p>(B) The Leading Edge Vortex (LEV) formed at the leading edge of the fore wings during the insect flight.</p

Aggregates of different mineral grains on the honey bee wings.

<p>BSE images. (A) Multi-grain aggregate of diverse mineral phases, including fine and ultra-fine grains of baryte (asterisks; EDX spectrum), and bigger particles of a phyllosilicate (arrows), whose EDX spectrum is shown in (B). Bar = 30 μm. (C) A multi-grain aggregate mainly composed of baryte. Bar = 10 μm. (D) A detail showing fragments of Na-rich plagioclase (arrowheads) and its EDX spectrum (note the contamination of baryte and possibly dolomite). Bar = 10 μm.</p

(A) Study area; (B) view of the Red Muds, and (C) the mine dumps of Cungiaus.

<p>(A) Study area; (B) view of the Red Muds, and (C) the mine dumps of Cungiaus.</p

BSE images of PM (bright spots) on the hind legs. (A) Metatarsus.

<p>Bar = 1 mm. (B) Distal tarsal segments. Bar = 150 μm. (C) Detail of the structures involved in the grooming behavior and pollen collection. The pecten spines (arrow) and the pyramidal spines of the auricle (arrowhead) convey and pack the pollen into the pollen basket located on the outer surface of the leg. The pollen comb (pc), composed by transverse rows of stiff spines, brush off pollen from the lateral surface of the body and collect wax scales from the abdomen. Bar = 300 μm.</p

(A) A galena fragment and (B) a detail showing a Fe-rich anthropogenic particle placed on a honey bee wing.

<p>(A) SE and BSE images of a galena triangular fragment (asterisks), placed next to a rounded iron particle (arrowheads). Bars = 30 μm. (B) SE image of the rounded particle mainly constituted of iron; on its surface (partially embedded into organic matrix) are detectable nanometric grains of baryte and plagioclases (arrowheads). The Pb and S peaks are related to the galena particle (asterisk) described above. Bar = 2 μm.</p

Honey bee head displaying PM (bright spots) almost exclusively along the medial plane, nearly between the median ocellus (mo) and the antennae, including the scapus (sc).

<p>BSE image. Bar = 1 mm.</p

Summary of mineral and anthropogenic compounds detected in this study.

<p>^a simplified after <a href="http://www.mindat.org" target="_blank">www.mindat.org</a>, and references therein</p><p>^b possibly as Fe oxide coatings found on most analyzed grains</p><p>^c coated by Fe oxides</p><p>^d detected as part of multigrain aggregates</p><p>^e not calculated</p><p>* postmining-derived particle</p><p>** soil-derived particle</p><p>*** industry-derived particle</p><p>^§ sea spray</p><p>Summary of mineral and anthropogenic compounds detected in this study.</p

SE and BSE images of dissected portions of the alimentary canal displaying spherocrystals (brighter particles).

<p>(A, B) An opened ventriculum, showing high concentration of spherocrystals inside the epithelium. Bars = 500 μm. (C, D) A detail of the epithelium. Bars = 30 μm. (E, F) Sperocrystals in a Malpighian tubule. Bars = 10 μm. lu = lumen of the ventriculum; Mt = Malpighian tubules.</p

Fine and ultra-fine particles of baryte evenly spread across the honey bee wing.

<p>BSE image. Bar = 10 μm.</p

Irregular-shaped anthropogenic particles on the honey bee body.

<p>(A) Particle mainly containing Fe found on a honey bee head. Bar = 50 μm. (B) SE and BSE images showing a particle containing Zn and Fe, partially hidden by hairs of a hind leg. Bars = 10 μm.</p