Factors in the Determination of Selected Trace Elements in Near-Shore U. S. Waters of Lakes Superior and Huron

摘要

Determinations of total As, Cr, Cu, Fe, Mn, and Pb in acidified unfiltered water samples from 48 stations representing the near-shore U.S. waters of Lake Superior, Lake Huron, and selected incoming streams gave overall mean concentrations and standard deviations (microgram/L) of 1.0 + or - 0.7, 0.9 + or - 1.8, 2.0 + or - 1.8, 236 + or - 819, 14 + or - 34, and 0.7 + or - 0.8, respectively, using flameless atomic absorption analytical methods. Total concentrations of Ni and Hg were usually less than the instrumental detection limits (microgram/L) of 0.8 and 0.02, respectively. Small losses of Hg, As, and Cr from solutions are possible in addition to a molecular spectral interference in the determination of As using the graphite furnace method. River waters usually were only slightly higher in total element concentrations than lake waters, except for Fe and Mn. Nearshore waters of both lakes were very similar in elemental composition.