AN IN-SITU FILTRATION EXTRACTION SYSTEM FOR THE RECOVERY OF TRACE ORGANICS IN SOLUTION AND ON PARTICLES TESTED IN DEEP-OCEAN WATER/

A system for in-situ filtration and extraction of organics in natural waters has been developed and tested down to 4000 m in the Atlantic Oc ean. Up to 2000 dm(3) water can be filtered and extracted at low suspe nded matter concentrations. The sampling equipment has new features fo r the analysis of trace organic compounds: contamination is extremely low, this can be checked and cured, if necessary, and water flow can b e selected and maintained at a constant rate. Various resins can be ap plied, with different optimum flow rates for the efficient extraction of the compounds of interest. The properties of the resin (here XAD-2) do not change with depth. The operation of the unit is controlled by menu-driven software. All relevant data are stored for later evaluatio n, Tests in the deep Atlantic resulted in total procedural blanks, inc luding sampling, as low as 0/003 pg dm(-3) for individual chlorobiphen yls (CBs), HCB and DDE and 0.5 pg dm(-3) for individual PAHs. Actual d issolved concentrations were in the range 0.005-0.1 pg dm(-3) for CBs, HCB and DDE and 0.5-140 pg dm(-3) for PAHs.