Analyses of heavy metals in sewage and sludge from treatment plants in the cities of Campinas and Jaguariúna, using synchrotron radiation total reflection X-rayfluorescence

► Analysis of sewage and sludge composition using SR-TXRF. ► Determination of the potentially toxic elements like Cr, Ni, Cu, Zn and Pb. ► Concentrations determined were compared with Brazilian quality standards. ► It was discovered possible illegal discharges of sewage. ► Comparison between raw wastewater and treated during wet and dry periods.