Summary: | A method involving acid digestion, dithizone extraction and atomic absorption spectrometry was developed to determine cadmium, zinc, copper, nickel, cobalt, silver and bismuth in sediments. The determination of lead and indium was also investigated but accurate methods were not developed. A demountable hollow cathode lamp was successfully employed for work on bismuth and indium. Modifications of the method made possible the determination of cadmium, zinc, lead, copper, nickel, cobalt and silver in biological tissues and in natural waters. Precision values were obtained on sediment samples from Southampton Water and the North Atlantic Ocean, Solent sea water samples and a sample of reference kale, and are listed along with detection limits in the following table. Matrix Cd Zn Pb Cu Ni Co Ag iij Cv DI Cv DI v DI V DI V DI Cv DI Cv DI Cv DI Typo I °6 1,n/g pg/o pn/g pg/0 n/s v PO/n po/n 6 ps/nMorinent 10 0,03 7 2,0 4 0,20 2 0 35 3 0,05 26 0,05 7 0,01 SedimeSo. Water 3 0,05 6 0,6 23 0,1 6 0,06 5 0,3 12 0,05 29 0,0513, Geological 7 0,03 3 0,6 13 0,03 4 0,05 11 0,03 15 0,01 0,01 TissueCv : Coefficient of variation DI : Detection limit The method was used on United States Geological Survey rock reference samples and on reference kale and good agreement with listed values found.A technique involving successive leaching with magnesium chloride, Chester-Hughes reagent and basic sodium pyrophosphate followed by hydrofluoric acid digestion was developed to determine the distribution of trace metals between the major sediment components. Iron, manganese, organic carbon, hydrocarbons, free water content and particle size were determined as well as the above trace metals in some samples used in studies on sediments from Southampton Water, the Bristol Channel, the River Liffey and a part of the North Atlantic Ocean. Correlations were often found between cadmium, zinc, copper, nickel, cobalt and silver, especially in polluted situations. Sediments were polluted in the vicinity of the Fawley Oil Refinery, copper being the most ...
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