evaluation of two different extraction techniques on determination of 〖pb〗^(+2) contents of wastes of dye manufacturing industries

extraction of trace amounts of toxic heavy metals from complicated environmental matrixes is a  challenging task. the aim of this investigation is the comparison of the extraction efficiencies and other related experimental variables ( chemicals, effect of ph, potential interfering ions) on the determination of inorganic lead ( ) which is present in waste water of dye industries. compared techniques are liquid liquid extractions followed by uv/visible spectrophotometric determination (lle-uv/vis) and solid phase extraction followed by flame atomic absorption determination (spe-faas). the detection limits are 23 ng.  and  0.36 ng.   respectively. the effects of sample flow-rate and preconcentration factor are also investigated. the experimental results indicate that preconcentration factor of 300 could be achieved. the techniques are applied for determination of  contents of wastes water of east tehran regions.