SIMULTANEOUS DETERMINATION OF METAL TRACES USING SPE PRECONCENTRATION ON AMBERLITE XAD-7 BY ICP-MS IN ENVIRONMENTAL WATER AND SAMPLE ECOTOXICOLOGY ASSESSMENT

摘要

This study has been focused on the determination of nine trace elements ~9Be, ~(51)V, ~(59)Co, ~(60)Ni,~(89)Y, ~(111)Cd, ~(208)Pb, ~(232)Th and ~(238)U by inductively coupled plasma mass spec trometry (ICP-MS) in natural waters and water samples after mining and processing of uranium. An ICP-MS spectrometer Agilent 7500ce, with a plasma generator of 27.12 MHz, power output of 1500 W and concentric nebulizer MicroMist with a cooled Scott chamber was used. The nonspectral interferences were eliminated by using a solution of internal standards 6Li for ~9Be, ~(45)Sc (~(51)V), ~(72)Ge (~(59)Co, ~(60)Ni, ~(89)Y), ~(103)Rh (~(111)Cd), ~(209)Bi (~(208)pb) ~(232)Th, ~(238)U).The spectral interferences were eliminated by using the Helium collision cell during meas urement. Monitored interfering elements were K~+, Na~+, NH_4~+, Ca~(2+), Mg~(2+), Al~(3+), Fe~(3+) and Cl~-, HCO_3~-, SO_4~(2-) PO_4~(3-). For the preconcentration polymeric sorbent Amberlite XAD-7 was used. Elements were retained as their chelates with different organic reagents: 4-(2-pyridylazo) resorcinol (PAR), 3,4-Dihydroxy-9,10-dioxo-2-anthracenesulfonic acid sodium salt (ALS), 8-Hydroxyquinoline-5-sulphonic acid (8HQS) and Ammonium pyrrolidinedithiocarbamate (APDC). The sorption process was studied under various con ditions with respect to pH. Sorbents were also conditioned with different surfactants: Benzyldimethyltetradecylammo nium chloride (Zephyramine), 1-etoxycarbonyl-pentadecyl-trimethyl-ammonium bromide (Septonex~?), Brij 35 or Sodium Dodecylsulphate (SDS). Various elution mixtures were also tested, the best re sults were obtained for the mixture of acetone and ethanol (1:1) in the presence of 1 mol·~(-1) HC1. The excess of acid and organic solvents were evaporated in Teflon~? dishes prior to the determination by ICP-MS. The Thamnocephalus platyurus as THAMNOTOXKIT F?, Daphnia magna as a DAPHTOXKIT F? and Artemia salina as Artoxkit M? are organisms, which were used for ecotoxicology assessment of water samples after min ing of uranium.