Ultrasonic extraction and field-portable anodic stripping voltammetric measurement of lead in dust wipe samples

Dust wipe samples were subjected to ultrasonic extraction (UE) in diluted n itric acid, and then analyzed for lead content using field-portable anodic stripping voltammetry (ASV), Recoveries of lead were determined from wipe m aterials which were spiked with certified reference materials (CRMs) contai ning known quantities of lead. Four different wipe materials and four diffe rent CRMs were tested, with and without filtration of aliquots of sample ex tract through 0.45 mum hydrophilic polytetrafluoroethylene filters. The CRM s consisted of paint, soil, particulate, and dust matrices. Wipe materials were chosen from those which have been found to meet the performance aspect s of an ASTM standard specification. UE/ASV experiments were carried out in accordance with newly published ASTM procedures for on-site extraction and electroanalysis, Recoveries were found to vary for different wipe material s and CRMs. For several CRMs, quantitative (80-120%) recoveries for UE/ASV were observed for one wipe material whether filtration was used or not, whi le other wipe materials required filtration for quantitative recovery. In t he case of one wipe material which contained detergents, quantitative recov eries could not be achieved whether filtration was used or not. The total a nalysis time for a sample set of 6-12 samples was 60-90 min, including extr action time and sample manipulation. The results of this work have provided information on the choice of wipe materials that can be used for quantitat ive lead measurements by UE/ASV in materials that are representative of sou rces of lead in surface dust. Published by Elsevier Science B.V.