• field sample preconcentration;
  • flow-injection;
  • lead;
  • seawater


A simple field-flow preconcentration system has been developed for lead determination in seawater. Seawater samples are collected in situ by passing them with a pump through minicolumns packed with poly(aminophosphonic acid) chelating resin to retain and preconcentrate lead, and remove the saline matrix. Minicolumns loaded with lead are then returned to the laboratory where they are inserted into a flow-injection system and eluted with a small volume of hydrochloric acid into the nebulizer-burner system of a flame atomic absorption spectrometer. The detection limit for lead in seawater was 2.8 ng l−1. This procedure was applied to the determination of lead in seawater samples from Galicia (Spain). © 2001 John Wiley & Sons, Inc. Field Analyt Chem Technol 5: 239–243, 2001