LAUSR

Abstract An inductively coupled plasma optical emission spectroscopy (ICP OES) method was developed for the determination of several metals (As, Ba, Ca, Cr, Cu, Fe, K, Mg, Mn, Ni, Sr, Ti, V, and Zn) in particulate matter (PM10) after acid extraction using a digester block. A complete 2 [4] factorial design was employed to explore the best conditions for ICP OES radiofrequency (RF) power, plasma argon flow (P), auxiliary argon flow (A), and carrier argon flow (N). Subsequently, figures of merit consisting of linearity, limits of detection and quantification (LOD and LOQ), and precision (recovery percentages) were evaluated by using the certified reference material (CRM) NBS-SRM-1633a Coal Fly Ash. Findings indicate that the optimum conditions for metal determinations in PM10 by ICP OES are RF = 1200 W; P = 10 L min-1; A = 0.60 L min-1, and N = 0.5 L min-1. Under these optimized conditions, recovery values for the metals detected in the CRM ranged from 81 % for Ni to 133 % for Fe, with LODs and LOQs between 0.02 ng m-3 and 0.06 ng m-3 for V and 37.1 ng m-3 and 122 ng m-3 for K, respectively, and relative standard deviation (RSD) values lower than 5%, indicating that the proposed optimization provides good accuracy and precision. This methodology was then applied to PM10 samples collected at Campos dos Goytacazes (Rio de Janeiro) during the sugarcane harvest of 2016/2017, in order to assess sugarcane burning impacts on local air quality.