Emissões atmosféricas de mercúrio – Estudo de caso: Descoberto/MG.

Abstract

Mercury (Hg) is a naturally occurring metal in the environment in various forms, mainly in three main categories: metallic mercury or elemental mercury, inorganic mercury and organic mercury. It can be found in all types of rocks, being obtained almost exclusively of cinnabar ore. It has been used in several sectors of industry, mining, among others, with anthropogenic sources that contribute most to concentrations in the environment. Any activity involving the handling and transportation of this substance automatically makes it available to one of the environmental compartments (soil, water and / or air). Mercury and its compounds can cause various damage to human health, and its harmful effects affect systems such as nervous, reproductive, digestive, renal, cardiac, immune and respiratory. On December 20, 2002, outcropping of elemental mercury was observed in the rural area of the municipality of Descoberto, Minas Gerais. After studies in the region, it was observed the need to better understand which factors influenced the volatilization of mercury in the area in question. Therefore, this study aimed to understand the behavior of atmospheric emissions of mercury in the municipality of Descoberto, Minas Gerais. Three campaigns were developed to collect Hg0 samples in 34 points. The average levels found in the air in campaigns 1, 2 and 3 were 37.91 ng m-3 (σ = 90.6), 8.77 ng m-3 (σ = 7) and 9.64 ng m-3 σ = 5), with medians at 3.7 ng m-3, 6 ng m-3 and 8.25 ng m-3, respectively. According to the results obtained, it is concluded that the atmospheric emissions of mercury continue to occur in the Municipality of Descoberto, in Minas Gerais. However, to understand the dynamics of Hg0 in the municipality, it is necessary to evaluate the Hg emission processes together with the meteorological variables and other environmental analyzes, and these data were collected under the same conditions.