الفهرس 
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Abstract
A new method was developed for the determination of trace metals in various environmental liquid and solid samples. The method was found to be applicable to surface waters, industrial waste, fish and dry milk. The new method is applied by preparing a ligand (N-{[phenylaminothioxomethyl] hydrazinocarbonylmethyl} trimethyl ammonium chloride) (PTHAC) from the reaction between Girard’s T and phenyl isothiocyanate and then use it for preparation of Cu2+, Hg2+, Cd2+ and Pb2+ complexes. The pH’s of all solutions were adjusted to 5-6. The trace metal contents of the samples are coordinated with the ligand and passed through the mini column filled with Amberlite IRC-50 resin with flow rate 2 ml.min−1. The metal complexes retained in the column were then eluted with suitable eluent. Analytical recoveries for the investigated metal ions were assessed for various concentration levels from 8 ppb to 10 ppm for each metal. The initial sample volumes were 50 or 250 ml and the final eluted volume was 10 ml. The studied metals were analyzed by flame atomic absorption spectrometry with analytical separation factor 5 or 25. The experimental results indicated that good recoveries were reached for all studied metals from 8 ppb to 3 ppm. Further, the isolated metal complexes derived from the interaction of ligand and Cu2+, Hg2+, Cd2+ and Pb2+ are characterized. The potential coordination sites are investigated using IR and 1H-NMR spectra. The structures of the isolated complexes proposed on the basics of spectral and magnetic studies. In conclusion, the metal contents at µgL−1 levels for copper, mercury, cadmium and lead were determined easily and with high accuracy. The obtained results provide new information of heavy metals as copper, mercury, cadmium and lead in drinking water, fish and dry milk from Mansoura city, Egypt. Based on sample analysis of the investigated metal ions, the concentration found does not exceed the permissible limits as “WHO” (World health organization).