Direct determination of Pi, In and Pb in sea water samples has been carried out by ETAAS with Zeeman background correction using molybdenum containing chemical modifiers and tartaric acid as a reducing agent. Maximum pyrolysis temperatures and the effect of mass ratios of the mixed modifier components on analytes have been investigated. Mo + Pd + TA or Mo + Pt + TA mixture was found to be powerful for the determination of 50 mu g 1(-1) of Bi, In and Pb spiked into synthetic and real sea waters. The accuracy and precision of the determination were thereby enhanced. The recoveries of analytes spiked were 94-103% with Mo + Pd + TA or Mo + Pt + TA and they are only 49-61% without modifier. (C) 1999 Elsevier Science B.V. All rights reserved.