ATMOSPHERIC DEPOSITION AND SOURCE APPORTIONMENT OF MERCURY AND LEAD OVER THE LAST 150 YEARS IN HIGHLAND PEATLANDS OF SOUTHEASTERN BRAZIL

Emmanoel Vieira Silva-Filho, Lúcio Fábio Lourençato, Andressa Cristhy Buch, Rut Amelia Díaz Ramos, Inácio Abreu Pestana , Vinicius Tavares Kütter, Eduardo Duarte Marques, Marcelo Correa Bernardes, Guillaume Bertrand, Luiz Drude Lacerda

Trace elements like mercury (Hg) and lead (Pb) are major global pollutants subject to long-range atmospheric transport, posing a threat for human and environmental health at a global scale. Both have a great affinity with organic matter and show limited mobility in soils under stable environmental conditions. Therefore, peatlands efficiently trap and act as reliable archives of changes in anthropogenic Hg and Pb fluxes over time. This study assessed the Pb and Hg accumulation in high mountain peatlands from two Conservation Units of the Rio de Janeiro State, SE-Brazil: Itatiaia National Park - INP and Serra dos Órgãos National Park – SONP to reconstruct the history of atmospheric trace metals pollution over the last 150 years. Results indicated that in both Parks, Hg and Pb concentrations were higher from 1950s, reflecting the beginning of the industrial development in Brazil. Whereas in INP, there was a decreasing accumulation of Hg and Pb, probably due to the influence of hydrological changes since 1950s, especially. On the other hand, in SONP, both metals’ accumulation rates were higher on current times (2013 to 1973) coincident with the increase in these elements’ emissions to the atmosphere in South America. The Hg enrichment factors (EF) were 215 and 130 for INP and SONP respectively, whereas the Pb EF values were 47.4 in INP and 24.7 in SONP. Such evidence indicates a current need for more effective environmental policies and guidelines to control emissions to the atmosphere of these two environmentally significant pollutants.