Issues also available electronically. (see inside front cover) ASPND7 28(4) 113–156 (2007) ISSN 0195-5373 A tomic S pectroscopy July/August 2007 Volume 28, No. 4 In This Issue: Total Urine Arsenic Measurements Using Inductively Coupled Plasma Mass Spectrometry With a Dynamic Reaction Cell Jeffery M. Jarrett, Robert L. Jones, Kathleen L. Caldwell, and Carl P. Verdon ...... 113 Methodologies for the Determination of Low Concentrations of Lanthanides in Biological Samples by ICP-MS A.K. Malik, D. Pozebon, V.L. Dressler, M. Zoriy, and J.S. Becker ............................ 123 Influence of Organic and Inorganic Acids Commonly Used in Soil Extraction and Digestion Procedures in the Determination of Elements by Inductively Coupled Plasma Optical Emission Spectrometry Ana Paula Packer and Maria Emília Mattiazzo ......................................................... 129 Aqueous and Acidified Slurry Sampling Approaches in the As, Sb, and Sn Determination of Urban Dust Samples by HG-ETAAS Jorge Moreda-Piñeiro, Carmen Moscoso-Pérez, María Piñeiro-Iglesias, Purificación López-Mahía .......................................................................................... 137 Antimony Determination in Mussel Samples by Atomic Absorption Spectrometry Using Palladium-Magnesium Nitrate as Chemical Modifier B. Curros-Gontad, M.C. Barciela-Alonso, M.D. Buján-Villar, E.M. Peña-Vázquez, and P. Bermejo-Barrera ............................................................................................. 144 Preconcentration of Nickel in Multi-walled Carbon Nanotubes Pretreated With Potassium Permanganate for Use as Solid-phase Extraction Adsorbent and Determination by Flame Atomic Absorption Spectrometry Qingxiang Zhou, Huahua Bai, and Junping Xiao .................................................... 150