Sandimirov S. Screening studies of POP levels in bottom sediments from selected lakes in the Paz watercourse / In State of the environment in the Norwegian, Finnish and Russian border area. The Finnish Environment. Finland, Jyvaskyla: Kopijyva Oy. 2007, №6.

Screening studies of PO P levels in bottom sediments from selected lakes in the Paz watercourse 94 126 Figure 10. Polychlorinated dibenzo-p-dioxins (PCDD) and polychlorinated dibenzofurans (PCDF) (pg/g dry weight) in surface (0-1 cm) bottom sediments. Numbers above bars are sum o f PCDDs and PCDFs (EPCDD/F). Applying o f toxic equivalency factors (TEFs) (NATO/CCMS, 1988) allowed calculation of 2378-TCDD toxic equivalents (TEQPCDD/F) for sediment from the studied lake. The highest TEQpccd/f values were found in Lake Kuetsjarvi (Table 8). PCDFs were the major contributors to the TEQPCDD/F. Only limited information exists on dioxin levels in freshwater sediments from the study area. In the end o f 1990s, studies on PCDD/PCDF levels in lacustrine bottom sediments were carried out on Varanger and Kola Penisulas (Schlabach and Skotvold, 1996; Skotvold and Schlabach, 1997; Skotvold and Savinov, 2003). High PCDD/PCDF levels were found in both areas. There is not recent available information for comparison. Figure 11 shows geographical distribution o f the TEQTCDD/Fcalculated for bottom sediments from the Arctic lakes in 1996 (Skotvold et al., 1997) and for reported data. Rapport APN- 514.3665.01 24