• Anda Abola Institute of Atomic Physics and Spectroscopy, University of Latvia
  • Maris Strazds Institute of Biology, University of Latvia
  • Zanda Gavare Depasrtment of Physics, Latvia University of Life Sciences and Technology
  • Rita Veilande Institute of Atomic Physics and Spectroscopy, University of Latvia



black stork, eggshells, mercury


Female birds whose bodies contain environmental contaminants produce eggs with shells that are likewise contaminated, making bird eggshells appropriate indicators for monitoring environmental toxins. Common contaminants include organic mercury compounds, especially methylmercury, which are known to bioaccumulate and biomagnify in the food chain. Black storks (Ciconia nigra) predominantly consume fish and are thus at risk for high mercury intake. In this study, we used eggshells of black storks as a proxy to reconstruct the concentration levels and distribution of mercury, a well-known toxic element, in various parts of Latvia. Preliminary analyses have shown that deposition levels of mercury vary in different parts of the eggshell. Specifically, the shell and shell membrane differ in their level of mercury contamination by an average factor of nine; therefore, we measured the mercury content in these components separately whenever possible. We analysed 34 eggshell samples from nesting sites in Latvia using an atomic absorption spectrometer with Zeeman correction Lumex RA-915M and its attachment for pyrolytic combustion. We found that mercury concentrations varied from 5 to 22 ng/g in eggshells and from 42 to 293 ng/g in shell membranes. We discuss possible contamination sources and reasons behind this disparity.



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Author Biographies

  • Anda Abola, Institute of Atomic Physics and Spectroscopy, University of Latvia
    PhD candidate Anda Ābola (maiden name Švāgere), Master thesis were dedicated to mercury detection in air, water and food; in SCOPUS: 5 publications - 11 citations (h-index: 2).
  • Maris Strazds, Institute of Biology, University of Latvia
    Dr. Biol. Māris Strazds in 2011 defended PhD thesis about Black Stork conservation ecology in Latvia (first person to defend PhD thesis on Black Storks in Europe); in SCOPUS: 4 publications – 11 citations (h-index: 3); main field of expertise is Black Stork observations, particularly nest inspections and sample collection.
  • Zanda Gavare, Depasrtment of Physics, Latvia University of Life Sciences and Technology
    Dr. Phys. Zanda Gavare (IAPS LU) has more than 15 years’ experience in the diagnostics of light sources and pollution control; in SCOPUS: 18 publications - 102 citations (h-index: 5).
  • Rita Veilande, Institute of Atomic Physics and Spectroscopy, University of Latvia
    Dr. Phys. Rita Veilande (IAPS LU) is currently a senior researcher at IAPS, with expertise in calculations and modeling (Wolfram Mathematica, MatLab) processes in Rydberg atoms, plasma, biophotonics and soliton type nonlinear equations. She has extensive experience in managing European fund’s projects, like the ESF project "Spectrometric techniques for the detection of heavy metal contaminants", which focused on mercury detection in the environment. (In SCOPUS: 11 publications; 52 citations (h-index: 4)).


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How to Cite

A. Abola, M. Strazds, Z. Gavare, and R. Veilande, “ASSESSING MERCURY POLLUTION USING BLACK STORK EGGSHELLS”, ETR, vol. 1, pp. 12–16, Jun. 2021, doi: 10.17770/etr2021vol1.6528.