TS-FF-AAS and multivariate calibration: A proposition for sewage sludge slurry sample analyses

This work describes a methodology for Cd and Pb determination in sewage sludge slurry samples using thermospray flame furnace atomic absorption spectrometry (TS-FF-AAS). The TS-FF-AAS system was equipped with a Ni tube atomizer placed on an oxidizing air/acetylene flame. Two multivariate calibration models based on partial least squares (PLS) were proposed using total peak profiles (recorded during 57 s). Metals concentration in the sewage sludge samples were from 1.87 to 6.26 mg kg−1 for Cd and from 101 to 327 mg kg−1 for Pb. The limits of detection and quantification were, respectively, 0.2 and 0.7 μg kg−1 for Cd and 8 and 26 μg kg−1 for Pb. These values were three times lower than the limits found when these metals were calibrated using linear calibration with aqueous standard solutions.