Análise de metais no material particulado atmosférico fino (mp2,5) na área urbana da cidade de Manaus

Abstract

Particulate matter is one of the main pollutants emitted to the atmosphere. This pollutant can be emitted by natural sources (biogenic emissions, resuspension of the soil, volcanic eruptions, etc.) and by anthropogenic sources (industries, fires, thermoelectrics, vehicular traffic, among other sources). Exposure to these particles and the substances present in their composition can cause adverse consequences for human health. Among these substances are metals, which have been studied by several researches related to the monitoring of air quality. Within this context, this work aimed to determine the concentrations of metals present in fine atmospheric particulate matter (PM2.5) in urban area city of Manaus-AM in 2018, as well as its seasonality and possible sources of pollution. The collection of MP2.5 was performed using a large volume sampler, with a flow rate of 1.13 m3/min, for 10 hours a day. For the determination of metals, the inductive coupled plasma optical emission spectrophotometry (ICP-OES) technique was used. The metals determined in MP2.5 were: Al, Ba, Ca, Cr, Cu, Fe, K, Mg, Mn, Na, Ni and Zn. Among the metals analyzed, Fe was the one with the highest concentrations, with an annual average of 1.26 μg m-3, followed by Ca, Cr and Al, which presented average annual concentrations of 0.35; 0.15 and 0.14 μg m-3, respectively. The concentrations of most metals evaluated showed a seasonal trend and showed higher values in dry period and lower values in rainy period. Regarding possible sources, vehicular traffic was identified as one of the main sources of pollution of the concentrations of these metals, and may also have contributions from the Industrial District of the city of Manaus.