Monitoring of Airborne Mercury: Comparison of Different Techniques in the Monte Amiata District, Southern Tuscany, Italy

• Published in: International journal of environmental research and public health Vol. 17; no. 7; p. 2353
• Main Authors: Rimondi, Valentina, Benesperi, Renato, Beutel, Marc W, Chiarantini, Laura, Costagliola, Pilario, Lattanzi, Pierfranco, Medas, Daniela, Morelli, Guia
• Format: Journal Article
• Language: English
• Published: Switzerland MDPI AG 31.03.2020; MDPI
• Subjects: Bark; Communication; Environmental monitoring; Lichens; Mercury; Metabolism; Metallurgy; Mining; Mosses; Pine trees; Samplers; Italy; biomonitoring; particulate Hg; tree barks; passive air samplers; lichens; airborne pollutants; mining area
• ISSN: 1660-4601; 1661-7827; 1660-4601
• DOI: 10.3390/ijerph17072353

In the present study, mercury (Hg) concentrations were investigated in lichens ( (L.) Hale, (L.) Ach., and (L.) Th.Fr.) collected in the surrounding of the dismissed Abbadia San Salvatore Hg mine (Monte Amiata district, Italy). Results were integrated with Hg concentrations in tree barks and literature data of gaseous Hg levels determined by passive air samplers (PASs) in the same area. The ultimate goal was to compare results obtained by the three monitoring techniques to evaluate potential mismatches. Lichens displayed 180-3600 ng/g Hg, and Hg concentrations decreased exponentially with distance from the mine. Mercury concentration was lower than in barks at the same site. There was a moderate correlation between Hg in lichen and Hg in bark, suggesting similar mechanisms of Hg uptake and residence times. However, correlation with published gaseous Hg concentrations (PASs) was moderate at best (Kendall Tau = 0.4-0.5, > 0.05). The differences occurred because a) PASs collected gaseous Hg, whereas lichens and barks also picked up particulate Hg, and b) lichens and bark had a dynamic exchange with the atmosphere. Lichen, bark, and PAS outline different and complementary aspects of airborne Hg content and efficient monitoring programs in contaminated areas would benefit from the integration of data from different techniques.