Deposition of dioxins in Flanders (Belgium) and a proposition for guide values

Since 1993 the VMM (Flemish Environment Agency) organises twice a year a me asurement campaign of the dioxin deposition in cooperation with the VITO (F lemish Institute for Technological Research). During this period the deposi tion of polychlorinated dibenzo-p-dioxins (PCDD) and polychlorinated dibenz ofurans (PCDF) has significantly decreased. Emission reduction programs and closing-down of major sources are the main reasons for this improvement. T here are still high depositions in the vicinity of ferrous and non-ferrous industries but reduction plans are in progress. A proposition for a guide v alue for deposition of PCDD/F has been made. Annual average depositions sho uld not exceed the range of 3.4-10pgTEQ m(-2) day(-1). (C) 2001 Elsevier Sc ience Ltd. All rights reserved.