Evaluating Spatiotemporal Resolution of Trace Element Concentrations and Pb Isotopic Compositions of Honeybees and Hive Products as Biomonitors for Urban Metal Distribution

Abstract

Assessing metal distributions in cities is an important aspect of urban environmental quality management. Western honeybees (Apis mellifera) and their products are biomonitors that can elucidate small-scale metal distribution within a city. We compare range and variations in trace element (TE) concentrations and lead (Pb) isotopic compositions of honey, bee tissue, bee pollen, and propolis collected throughout Metro Vancouver (BC, Canada). Honey, bee, and bee pollen results have similar TE and isotopic trends; samples collected in urban and industrialized areas exhibit elevated concentrations of anthropogenically influenced TE (e.g., Pb, Zn, V, and Ti) and a less radiogenic Pb isotopic composition (i.e., lower 206 Pb/ 207 Pb and elevated 208 Pb/ 206 Pb) relative to their suburban and rural counterparts. For example, 206 Pb/ 207 Pb, 208 Pb/ 206 Pb in honey range from 1.126, 2.131 and 1.184, 2.063; extremes measured in honey from urban and suburban/rural areas, respectively. Except for propolis, measured and interpolated (kriged) results in all materials reflect the immediate zoning or land use setting near the hive, providing kilometer-scale geospatial resolution, suitable for monitoring urban systems. Statistical analysis reveals that no systematic variations or intra-or inter-annual trends exist in TE concentrations or Pb isotopic compositions, including among sampling and field methods (i.e., old vs. new hive equipment and honey from the brood nest box vs. honey super). The results of this systematic study using honeybees and hive products in Metro Vancouver provide a robust, current baseline for future comparison of local land use and environmental policy change.

Honey Maps the Pb Fallout from the 2019 Fire at Notre-Dame Cathedral, Paris: A Geochemical Perspective

“…These concentration trends are in agreement with previous studies that examined metal distribution patterns in Paris and the surrounding region using topsoil and aerosols [29][30][31] and in other urban areas (Vancouver, Canada and Sydney, Australia) using honey. 11,12,14 The (geometric) mean Pb concentration measured in central Parisian (Fig. 1, 'Zone 1') honey in 2019 (0.014 μg/g) is higher than the 2018 Parisian honey blend (0.009 μg/g) and higher than that of honey from the Rhône-Alpes (0.004 μg/g) (Fig.…”

“…following the sampling methods of Smith et al 11 and Smith and Weis 14 ). Sampling in July following the fire is reasonable considering several factors: the tendency of Pb to linger (especially bound in topsoil) once deposited in the environment 20,21 , the kinetics of honey production (i.e., worker bee life cycles, inter-seasonal reproducibility of metals 14 ), and a required contribution of ~100,000 foraging flights to produce 1 kg of honey, ensuring a natural threshold of homogeneity in the honey. 22 S2).…”

“…12 Lead isotopic compositions of honey provide additional information by permitting assessments of potential sources of Pb in the environment surrounding the hive. 11,12,14 All Pb sources and sinks are composed of various relative abundances of four stable isotopes:…”

Essential (Mg, Fe, Zn and Cu) and Non-Essential (Cd and Pb) Elements in Predatory Insects (Vespa crabro and Vespa velutina): A Molecular Perspective

“…The higher concentrations of Mg, Fe and Zn determined in V. crabro associated with higher Pb and Cd concentrations may be due to a different environmental exposure. In fact, A. mellifera and other Hymenoptera are considered interesting biomonitor organisms that have been used to assess element distribution in different environments worldwide [ 7 , 10 , 18 ].…”

“…Essential and non-essential element concentrations in honeybees and wasps have been widely used as indicators of environmental pollution [ 7 ]. However, essential elements, in particular Mg, Fe, Zn and Cu, carry out different biochemical functions related to cell metabolism and regulation, and their concentrations are controlled by sophisticated homeostatic mechanisms which include uptake, transport, intracellular distribution and excretion [ 8 ].…”