Analysis of heavy metal aerosols on filters by laser-induced plasma spectroscopy

Particulate heavy metals can lead to severe toxic and carcinogenic effects in humans when inhaled in higher concentrations. For the development of a q uasi-continuous emission monitor based on automatic filter sampling on a fi lter band, laser-induced plasma spectroscopy (LIPS) was studied for analysi s of heavy metal aerosols on quartz fiber filters. The system consists of a 19-inch laser and detector module connected to a miniaturized sensor head through fiber optics, allowing maximum flexibility of the set-up. Parameter s for optimum time-resolved analysis, i.e. detection wavelength, timing and filter material, were established. The LIPS investigations were accompanie d by a rigorous reference analysis based on total reflection X-ray fluoresc ence (TXRF) analysis. The detection limits for heavy metals (Cd, Ni, As, Co , Mn, Sb, Cr, TI, Sn, V, Cu and Ph) on filters varied between 0.01 and appr oximately 0.91 mug cm(-2), corresponding to volume detection limits of 0.02 -2.73 mug m(-3). Analysis of filter samples from waste incineration demonst rated the potential of the LIPS approach. In combination with an echelle sp ectrometer, ambient samples from environmental monitoring could be characte rized in much better detail, due to the improved detection limits and the s uperior spectral resolution, and spectral range of the echelle. (C) 2001 El sevier Science B.V. All rights reserved.