Determinação multielementar em amostras de açúcar empregando a espectrometria de fluorescência de raios-X por dispersão de energia após procedimento de diluição

Abstract

Sugar is widely consumed and can represent a route of exposure to potentially toxic metals, making it essential to monitor its contamination to ensure food safety and public health. This study evaluated samples of white, demerara, and refined sugars for the presence of Co, Cr, Cu, Ni, and Zn using energy-dispersive X-ray fluorescence spectrometry (EDXRF). The samples were diluted in nitric acid solution and applied directly to the instrument’s sample holders for measurement of analytical signals. Calibration was performed using analyte standards prepared in sucrose, ensuring matrix matching and external calibration. The calibration curves showed good linearity, with limits of detection of 0.30, 0.40, 0.40, 0.30, and 0.60 mg kg⁻¹ for Co, Cr, Cu, Ni, and Zn, respectively. The addition and recovery tests yielded results between 82% and 108%, and the relative standard deviation (RSD) was below 7% in both intraday and interday evaluations. Concentrations obtained by EDXRF were compared with those determined by inductively coupled plasma optical emission spectrometry (ICP OES) after microwave-assisted acid digestion, with no statistically significant differences observed between the methods. The average concentrations for Co, Cr, Cu, Ni, and Zn ranged from 0.89 to 1.63 mg kg⁻¹, 2.10 to 3.66 mg kg⁻¹, 1.02 to 1.93 mg kg⁻¹, 1.23 to 1.85 mg kg⁻¹, and 2.66 to 4.04 mg kg⁻¹, respectively. The risk assessment indicated that the detected levels do not pose toxicological, carcinogenic, or non-carcinogenic hazards, suggesting that sugar consumption does not pose long-term health risks associated with the evaluated elements.